Solid waste management is challenging in many countries, especially developing economies. The impacts of the pandemic continue to be felt and have indicated secondary impacts on waste management. This work draws on data on household solid waste (HSW), healthcare waste (HCW), and recyclables collected in the Rio de Janeiro municipality, analyzed from January 2018 to December 2022. As expected, the collection of HCW in Rio de Janeiro municipality experienced a noticeable increase in 2020 and 2021, with an average of 46.9 tons and 54.3 tons collected, respectively. Notably, 2021 saw a significant 30% increase compared to 2019 (p-value<0.001). No significant difference was observed in recyclables collected from 2018 to 2021. The average recyclable amount was 3,638 and 3,747 tons per month in 2020 and 2021. In contrast, the monthly amount was equal to 4,819.5 tons in 2022, representing an increase higher than 32% compared to previous years (p-value<0.05). Our findings can be used to adapt and improve waste systems to cope with similar emergency scenarios in the future, serving as a template for municipalities with similar challenges.

Any Hospital’s primary goal is to restore human health and save lives through health services provided to patients, but at the same time, hazardous wastes are produced. Inconsistent management of unsafe wastes might cause adverse effects and other issues to workers, the environment and public health. Segregation is considered the critical stage for a successful Healthcare Waste Management. Mixing hazardous waste with non-hazardous waste will be avoided by correctly applying practices at the segregation stage. This study aimed to assess personnel’s knowledge about Infectious Medical Waste and segregation practices used at six wards in Nicosia General Hospital. An analytical cross-sectional study was conducted, and data were collected through a structured self-administered questionnaire. The Statistical Package of Social Science (SPPS) version 25 was used with a minimum statistical significance α=0.05. The study population was nurses, nurse assistants, ward assistants and cleaners working at the study wards. Out of 191 questionnaires, 82 were received, with a response rate of 42.93%. Most participants were female (72%) and nurses (85,4%). Participants had medium to good knowledge about Infectious Medical Waste management and good knowledge regarding segregation practices applied in their ward. Segregation was not carried out as it should have since most participants stated that Infectious Medical Wastes were mixed with non-hazardous waste. Correct answers given by the participants regarding color-coding of different Healthcare Waste categories was 67.5%, and only four answered correctly to all questions. Although participants knew segregation practices and the colour-coding process applied for Healthcare Waste, they didn’t use them satisfactorily. They applied methods regarding segregation without specific training, knowledge and guidance. Due to the issue's importance, training programs must be implemented and performed.

By the end of 2023, biowaste must be completely separated or recycled at source based on the EU legislation. Separate biowaste collection and valorisation towards biofuels could play an essential role in the biobased circular economy. In this context, the principal goal of this paper was to demonstrate in pilot scale the technological solution of bioethanol production via the utilisation of urban source-separated biowaste within the city context of Athens, Greece. More specifically, the main aim was the demonstration of a pilot system in continuous operation (over 10 operating cycles) with real feedstock – wet separately collected biowaste. From the 11 pilot trials performed with wet feedstock, the mean starch and cellulose degradation of the pilot trials amounted up to 80.69±16.27% and 79.41±10.37% respectively, while the bioethanol yield was 74.05±6.82%. The latter was comparable to that of more intensive pretreatment methods. Homogenization and shredding that was applied in this study, stand as promising and cost-effective pretreatment methods for bioethanol production from wet feedstock. Further research is needed to optimize conditions and evaluate scalability. Nevertheless, pilot scale testing is a crucial step in the development and deployment of this technology since it serves as a bridge between laboratory research and full-scale implementation, offering a practical and controlled environment to validate and optimize the technology while minimizing risks and uncertainties.

In road construction, before applying an asphalt or concrete surface, the ground must be compacted and stabilized. There are two basic methods of soil stabilization: in situ and in a stationary node (ex-situ). The method of performing stabilization in place (in-situ) is the most frequently used method due to its convenience and lower price. The most popular type of binder for stabilization is a hydraulic binder (most often cement and various ashes). Such stabilization is performed at a depth of 10-50 cm, achieving the desired load-bearing parameters. In order to improve them, various chemical additives for stabilization are often used, such as ion exchange compounds, additives based on sulfuric acid, additives based on vinyl polymers or even organic additives using lignosulfonates. However, the use of such additives is associated with much greater costs and environmental burden, resulting in seeking for cheaper and equally effective alternatives. The win-win situation would be for instance recycling the problematic waste-based materials that on one hand are landfilled or impossible to recycle and on the other hand cause problems for the waste producers. Therefore, an interesting issue is the production of stabilization additives from various types of waste materials. As a result of the extensive testing of various waste-based materials blends with soil, the mechanical (compressive strength after 7 and 28 days) and hydraulic (capillary rise, water absorption, frost resistance) soil properties were measured. The optimization process led to obtaining additives compositions ensuring the best strengthening and sealing properties. These were for sandy soil: Pure foil (wax emulsion), Pure foil (wax emulsion) + waste sulphuric acid, RDF from waste tires (wax emulsion), Pure foil (wax emulsion) + “by-pass” waste ash + NaOHx2 and for clayey soil: Pure foil (wax emulsion) + NaOH, Pure foil (wax emulsion) + waste sulphuric acid, Tequant, Pure foil (wax emulsion).

Environmental perception is a powerful tool for identifying community needs and potential within their surroundings. This study assessed tourists' environmental perception regarding solid waste and its impact on the Hurtado balneary, located in Valledupar, Colombia. From May to July 2023, the investigation delved into the environmental attitudes and behaviors of 769 balneary users by employing a combination of observation, photographic documentation, and a comprehensive 21-question online survey. The findings unveiled compelling insights: an overwhelming 98.8% of participants acknowledged the adverse effects of solid waste on the environment, with an impressive 98% demonstrating a willingness to participate in waste management efforts. Alarmingly, 42.13% exhibited limited awareness of waste management practices, reflecting a lack of public interest and commitment (41.61%). Statistically significant disparities emerged: 59% of waste items were not appropriately disposed of in designated receptacles. Reasons for this included a lack of a sense of belonging (50.2%) and inadequate environmental education (45.6%). 96% expressed the need for river conservation signage, while 59.8% had not engaged in environmental training. The implications of these results extend beyond the Hurtado balneary, potentially informing solid waste management strategies in other aquatic environments. Furthermore, this investigation aligns with three critical Sustainable Development Goals: SDG 12, emphasizing responsible consumption and production; SDG 13, addressing climate action; and SDG 15, advocating for life on land and below water. Keywords: Tourism; solid waste; surface water; environmental management.

An estimated 38 million individuals, out of a total population of around 126 million, reside in urban areas of Bangladesh. The surge in urbanization and water consumption has led to a significant rise in waterborne sanitation systems within the country. One cost-effective solution for wastewater treatment is the utilization of septic tanks, which operate as anaerobic reactors, with their efficiency being closely tied to temperature conditions. This research focuses on evaluating the organic removal capabilities of a septic tank located on the Khulna University of Engineering and Technology (KUET) campus. The results show that a septic tank's ability to remove organic matter depends on the temperature, with higher temperatures making the removal process more effective. Additionally, the Total Suspended Solids (TSS) levels were observed within a range of 110–280 mg/L, 200–1030 mg/L, 160–880 mg/L, and 190–220 mg/L for the 1st, 2nd, and 3rd chambers, respectively. The maximum recorded pH values were 7.14, 7.13, and 7.11, while the minimum pH values were 7.06, 7.05, and 7.04, corresponding to the same chambers. Furthermore, the organic removal efficiency concerning dissolved oxygen (DO), nitrate (NO3-N), and pH levels remained within acceptable limits. These results suggest that a simple treatment unit like a septic tank can effectively render previously unacceptable and unhygienic water suitable for safe disposal and potential reuse, ultimately improving the management of septic tank wastewater.

This study deals with the computational analysis of the kinetic processes of a microbial electrolysis cell assisted-anaerobic digestion (MEC-AD) treating raw-waste activated sludge (WAS), comparatively with a conventional AD, as well as the effect of the Organic Loading Rate (OLR) on the system’s performance. The aim was to derive a single kinetic and mathematical model for the study of the MEC-AD, using the ADM1 framework, which can be utilized to extract the effect of an applied potential on the kinetics of AD. The experimental data were obtained from the long-term, continuous operation of two identical reactors (an AD and a MEC-AD), which were operated at different OLRs (1.1, 1.7 and 2.9 gCOD/(L*d)). The results showed that the MEC-AD yielded improved biomass yields, substrate consumption kinetics and 1st order disintegration kinetics, with a predominant contribution to disintegration of complex particulates, comparatively with the AD. Moreover, it enabled operation at higher OLRs (achieving the highest divergence from the AD at the OLR of 4.14 gCOD/(L*d)), therefore accelerating sludge treatment, as well as an improved performance at an increased solids retention time (SRT). These findings can serve as a quantitative guide for the effects of the operating parameters on the raw-WAS-fed MEC-AD performance.

Additive Manufacturing (AM) has been proving suitable to support or even replace traditional manufacturing in several industries, offering many advantages such as delivery time and reduction in terms of material waste, energy consumption and greenhouse gas (GHG) emissions. This study aimed to carry out a comparative assessment of the life cycle, from gate to gate, in the production of a low alloy carbon steel flange part using ER-90 wire. The methods utilized were Wire and Arc Additive Manufacturing (WAAM) and conventional manufacturing (CM) by forging, and comparative factors were energy demands, GHG emissions and generated solid waste. The total energy consumption in WAAM was 10,239.40 MJ, total carbon footprint in CO2 equivalent (CO2e) was 714.1 kgCO2e kg-1, and generated solid waste was 68.6 kg, respectively, 90%, 95% and 76% lower than consumption calculated in conventional manufacturing.

Acerola (Malpighia spp.) is a tropical plant genus of shrubs and trees whose fruit is rich in nutrients and bioactive compounds. However, its production generates significant waste that could pose an environmental issue. This review aims to summarize recent research on the potential uses of acerola wastes, including the extraction of bioactive compounds such as polyphenols, carotenoids, and pectins, as well as the development of materials such as nanomaterials, chitosan, and biofuels. Additionally, the paper discusses the potential medical applications of acerola wastes, such as wound healing, antioxidant, and anticancer effects. Finally, the paper explores the challenges and opportunities of using acerola waste as a sustainable source of raw materials and energy. The findings suggest that acerola waste could be a valuable resource for developing high-value products and promoting sustainable production practices in the fruit industry.

As one of the important wastes, waste PET pollutes human living and natural environment seriously. PET is an important solid waste that needs to be recycled at present. The complete degradation of PET was realized at low temperature. The lipophilic hydrophobic membrane was formed on the surface of stainless steel mesh (SSM) by a simple dip coating method, and the oil-water separation material was successfully prepared. Due to the load of degradation products, the surface roughness of SSM increased from 19.09 μm increased to 62.33 μm. The surface changed from hydrophilic to hydrophobic, and the water contact angle increased to 123o. The oil-water separation flux of modified SSM is 9825 L/(m2·h) and the separation efficiency is 98.99%. The modified SSM has good reuse performance. This hydrophobic modification method can also be used to modify other porous substrates, such as activated carbon, filter paper, foam, and other materials. In this study, the porous substrate modified by the degradation product of waste PET was used to prepare oil-water separation materials, which not only solved the problem of white pollution, but also reduced the dependence on non renewable resources in the conventional preparation methods of oil-water separation materials. The research provided new raw materials and methods for the industrial production of oil-water separation materials, and had important application prospects.

The paper presents the relationship between the efficiency of the process of skin onion peeling and its effect in the form of waste. The research was carried out on a pilot test stand for onion peeling. The process variables were compressed air with a pressure of (p) and valve controlling opening time of flow (t). The experiment took into account the influence of the onion diameter (d0) and its hardness (H). The obtained results were subjected to statistical analysis. Standard deviations were of the percentage loss of onion mass in the form of the skin removed of onion peeling in the process in relation to obtained aver-age values. Tukey's multiple comparison test was performed in order to identify the importance of individual process variables on the final effect of onion peeling. This was the basis for the development of a predictive model in the form of a nonlinear regression Mp=f(p,t,d0,H), which is a mathematical description of the peeling onion skin process . Finally, the response surface area of relationship between analyzed variables was determined. The results of research showed the peeling efficiency of the onion and waste of skin mass depend on the compressed air pressure. Extending the onion blowing time does not improve the process efficiency, while the hardness and size of the onion are irrelevant to the process.

The performance of recycled aggregate concrete deteriorates due to the defects of adhesive mortar, pores and cracks on the surface of recycled aggregate. It is of great engineering significance to modify the reclaimed aggregate to improve its performance and adaptability. In this paper, the physical and chemical properties of waste concrete recycled aggregate are reviewed. Then, the existing modification methods and technologies of recycled aggregate, including physical, chemical and biological methods, are reviewed. Finally, the existing problems of the current modification technology are summarized, and the future research direction is proposed. It is expected to provide a new idea and method for the modification of waste concrete recycled aggregate.

In South Korea, demolition waste (DW) management has become increasingly significant owing to the rising number of old buildings. Effective DW management requires an efficient approach that accurately quantifies and predicts the generation of DW (DWG) of various types, which necessitates access to the required information or technology capable of achieving this. Hence, we developed an artificial intelligence-based model that predicts the generation of ten DW types, specifically from buildings in redevelopment areas. We used an artificial neural network algorithm with < 10 neurons in the hidden layer to derive individual input variables and optimal hyperparameters for each DW type. All DWG prediction models achieved an average validation and test prediction performance (R²) of 0.970 and 0.952, respectively, with their ratios of percent deviation ≥ 2.5, ver-ifying them as excellent models. Moreover, a Shapley additive explanations analysis revealed that DWG was most impacted by the floor area for all the DW types, with a positive correlation with DWG. Conversely, other factors showed either a positive or negative correlation with DWG de-pending on the DW type. The study findings will enable demolition companies and local gov-ernments in making informed decisions for efficient DW management and resource allocation by accurately predicting the generation of various types of DW.

Thermoelectric (TE) waste heat recovery has attracted significant attention over the past decades, owing to its direct heat-to-electricity conversion capability and reliable operation. However, methods of system-level TE design optimization for specific application systems have not been thoroughly investigated. This work theoretically studies the performance optimization and exergy analysis of TE systems for recovering waste heat from the exhaust ducts of a gas turbine power plant. A numerical tool has been developed to solve the coupled charge and heat current equations with temperature-dependent material properties and convective heat transfer at the interfaces. Our calculations show that at the optimum design with 50 % fill factor and 6-mm leg thickness made of state-of-the-art Bi2Te3 alloys, the proposed system can reach power output of 10.5 kW for the TE system attached on a 2 m-long, 0.5 x 0.5 m2-area exhaust duct with system efficiency of 5 % and material cost per power of 0.23 $/W. Moreover, our extensive exergy analysis reveals that only 1 % of the exergy content of the exhaust gas is exploited in this heat recovery process and the exergy efficiency of the TE system can reach 8 % with improvement potential of 85 %.

The management and classification of solid waste is one of the most important challenges around the world, in order to sustain economic growth and preserve the environment. The objective is to propose the use of Smart Ecological Points as a strategy to address the problem related to the solid waste management system at the source, which has become one of the biggest problems globally and Colombia is no exception. The article describes the current state of the problem in the country and in turn, presents the possibility of developing a prototype corresponding to a low-cost Smart Ecological Point supported by the use of an experimental capacitive sensor and Machine Learning algorithms, which will reduce the time necessary for the classification of recyclable and non recyclable waste, minimizing the health risks and increasing the percentage of waste that can be reused, by reducing the probability of being contaminated at the source, an aspect that is very common when done manually. According to the results obtained, it was evident that the proposed prototype made an adequate classification of waste, generating the possibility of being manufactured with existing technology in the environment, in order to promote adequate waste classification at the source.

Organic fertilizers are fertilizers made from organic materials which are partly or wholly derived from waste materials, the function of these fertilizers is to improve the physical, biological, and chemical properties of the soil, these fertilizers are processed through the composting process, these fertilizers are very much needed because they are difficult to obtain at a high price. expensive. This study aims to obtain data on the growth and yield of sweet corn, due to the use of agricultural waste as organic fertilizer. The research method was experimentally consisting of 5 treatments and 5 replications; ie P0 = Without organic fertilizer (control) P1 = Dosage of organic fertilizer 2.5 tons/ha, P2 = Dosage of organic fertilizer 5 tons/ha P3 = Dosage of organic fertilizer 7.5 tons/ha, P4 = Dosage of organic fertilizer 10 tons /ha using a Randomized Block Design (RBD) The results showed that organic fertilizer had a significant effect on plant height aged 30, 40 and 50 DAP, had a very significant effect on cob length at a dose of 10 t.ha-1 and, had no significant effect on cob weight, will still have a high weight of 350 g.cob-1 From this description it can be concluded that organic compost can be used as a substitute for chemical fertilizers which provides an increase in the growth and production of sweet corn plants at the use of 10 tons/ha.

This paper presents the results of investigations on the pyrolysis of tyres waste in a laboratory fixed bed batch reactor. The results regarding the influence of either the reaction temperature (425, 450, 475, and 500 °C) and the flow of the inert gas (0, 100, 300, and 500 mL/min) on products yield (referred to pyrolysis of waste tyres) are also considered and discussed. On the basis of the above mentioned findings, the most appropriate experimental conditions were selected to contribute to a higher yield of pyrolysis oil. The sample of pyrolysis oil obtained from the experiments carried out in the selected optimal conditions (reaction time 120 min, temperature 450 °C and the inert gas flow of 100 mL/min) was subjected to a calorimetric and infrared spectroscopy analysis. The results of IR spectroscopy analysis on this oil sample showed the following content in percentages (by mass): 32.59 % of aromatics, 51.06 % of paraffins and 16.35 % of naphthenes. The pyrolysis oil so obtained has a high calorific value (42 MJ/kg) and a low sulfur content (0.41 % by mass), which makes it an excellent raw material for energy production. The solid product, i.e. pyrolysis char or carbon black, has the potential to be used as an adsorbent or catalyst support after an activation process, which changes its irregular pore structure to a more voluminous one, making the overall structure more crystalline and symmetrical. Pyrolysis coal has a fairly high calorific value of 31 MJ/kg, when compared to typical solid fuels, so it can be used in energy production or as a feedstock for the gasification process.

Derelict asbestos mine sites in South Africa pose a considerable risk to human, environmental and socio-economic health. Comprehensive mineralogical and geochemical datasets for the existing hazardous geological materials still exposed in Southern African derelict asbestos mines remain largely non-existent, as very little published and up-to-date literature is available. In this study three representative types of asbestos mineral fibres from derelict asbestos mines in Southern Africa, namely chrysotile from Havelock mine, amosite from Penge mine and crocidolite from Prieska mine are characterized mineralogically and geochemically to critically evaluate real-life hazards in rural and asbestos-fibre contaminated regions. The samples were examined using polarising light microscopy, X-ray fluorescence (major and trace elemental analysis), X-ray diffraction (including Rietveld refinement), specific surface area analyses and bio-durability tests. Data are discussed in view of their potential toxicities on both human health and the environment in the context of developing countries. Finally, information on the mineralogical and geochemical status of asbestos mine waste and its importance as baseline data for rehabilitation considerations is also evaluated.

The agricultural ecological environment provides an important resource guarantee for social development. The extensive management mode of agriculture in China has not fundamentally changed; the contradiction between production and governance is still prominent, and the management of agricultural surface pollution has a long way to go. Based on the data of 547 rural households in Jiangxi province, this paper uses the Ordered Logit, 2SLS, and moderation effect model to analyze the mechanism between social norms (SNs) and rural households’ (RHs) disposal of pesticide packaging waste (PPW) and to test the moderation effect of environmental regulation (ER) in the influence path of SN to RHs’ disposal of PPW. The results show that (1) descriptive and directive norms can promote RHs not to litter PPW. However, the role of surrounding crowd supervision (directive norms) is more obvious than the behavior of the surrounding crowd (descriptive norms). The consistent conclusion was still obtained after the robustness test and endogeneity treatment. (2) The results of the moderation effect test showed that reputational incentives strengthened the promotional effect of directive norms on RHs' behavior of not littering PPW; punitive regulation hindered the promotional effect of descriptive norms on RHs' behavior of not littering PPW. Based on the findings of the study, the following policy recommendations are put forward: continue to strengthen the guidance and soft binding force of informal institutions such as SNs; accurately locate the target groups and formulate differentiated measures; pay attention to the complementary nature of formal and informal institutions, and reasonably formulate environmental regulations to fit in with SNs.

Since a large amount of sewage sludge (WSS) has been generated daily, it is necessary to explore effective methods for utilizing WSS. Although a photo-fermentation system sometimes alters the characteristics of microbial functions, there are no attempts to perform the photo-fermentation using WSS which is regularly treated under a dark-fermentation style. In this study, the effect of photo-fermentation (photo-irradiation) on anaerobic digestion using WSS was revealed. Photo-irradiation during the anaerobic digestion of WSS significantly reduced the amount of organic acids and hydrogen sulfide and methane production was also suppressed. However, it was shown that the activity of sulfate-reducing bacteria in WSS under the light treatment increased. Photo-irradiation also stimulated the growth of green-sulfur bacteria and induced anoxygenic photosynthesis, by which the fermented samples turned green linking with the consumption of hydrogen sulfide. Finally, a dark/light switching fermentation was able to reduce only hydrogen sulfide while methane production remained the same.

A layout of urban waste fired zero emission power plant is described in this paper. The principle of layout, which comes from similar coal-fired plants retrieved from the literature, integrates gasification with a power generation section, and implements two parallel conversion processes, one supplied by the heat of the gasifier consisting of a thermoacousticmagnetohydrodynamic (TAMHD) generator, while in the second one the syngas is treated in order to obtain almost pure hydrogen, which is fed to fuel cells. The CO2 deriving from the oxidation of Carbon base is stocked in liquid form. The novelty of the proposed layout lies in the fact that the entire conversion is performed without solid moving parts. The resulting plant avoids any type of emissions in the atmosphere, increases mechanical efficiency as compared to traditional plants, thanks to the absence of moving parts, nonetheless, resolving at its root the ever-increasing waste-related pollution problems.

Anthropogenic chemicals are fundamental to our standard of living in modern society. Unfortunately, some chemicals are persistent and can enter waste streams and ultimately the environment. Commonly used household products including pharmaceuticals and personal care products are an important source of contaminants. The aim of this study was to develop an “Up-the-pipe Solutions” framework to raise awareness about the presence and potential risks of chemicals found in household products to reduce their levels in waste streams or substitute them with less harmful alternatives. This approach based on The Natural Step framework and the concept of essentiality recognises the importance of engaging the community to raise awareness around the consequences of our daily activities and behavioural patterns that can lead to the release of persistent contaminants in main waste streams from the kitchen and bathroom and green wastes we generate.

The aim of this study is to examine an efficient and environmental friendly process for hydrolyzing starch, an industrial-derived by-product of the potato processing industry, and to use the produced hydrolysates as substrates for methane production. A full factorial experiment was designed and the optimal concentrations of FeSO4·7H2O, H2O2 and temperature were determined obtaining a yield of 99.5%, with a total carbohydrates content equal to 28.65 g, when the input parameters were at their high level: FeSO4·7H2O 1.00g/L, H2O2 0.51 g/L and temperature 70.0oC. The hydrolysis kinetics were also examined revealing that temperature was the most important factor among the three optimization parameters. Furthermore, biodegradability tests were carried out to measure the methane production potential from the produced hydrolysates. The specific methanogenic activity was reached 0.669 g CODCH4/gVSS-day proving the effectiveness of the hydrolysis process and highlighting the potential of this food manufacturing by-product for bioenergy production. A preliminary cost analysis showed that a small investment for utilizing the starch in an existing wastewater treatment facility of a potato processing industry becomes profitable before the end of the 3rd year obtaining a NPV 37.5% higher than the NPV of the current utilization scenario.

The phosphogypsum (PG) pile of solid waste is of immense proportions and poses a grave threat to the ecological environment, with its reserves steadily increasing year after year. The urgent need for large-scale consumption and high-quality utilization of PG in industrial production has become apparent. The present study provides a comprehensive analysis of the correlation be-tween the macroscopic mechanical properties and microstructure of PG, elucidating the crystal morphology characteristics in different phases and outlining the crystallization preparation pro-cess. By integrating the physical and chemical properties of diverse PG phases with the intricacies associated with its preparation process, it is imperative to explore avenues for its high-value utili-zation, investigate possibilities for industrial-scale production, and analyze and predict the appli-cation trends and developmental directions in comprehensive PG utilization. These endeavors hold immense significance in guiding the realization of resource utilization potential inherent in PG.

The macro-litter (plastic) sea bottom pollution of 14 city harbors and marinas in North Africa and in the western Baltic Sea was investigated using a new simple mobile underwater camera system. The study was complemented by a harbor manager survey and 3D-hydrodynamic transport simulations. The average pollution in German marinas was 0.1 particles/m² sea floor (0.04–1.75). The pollution in North African marinas on average was 7 times higher (0.7 particles/m²) and exceeded 3 particles/m² in city center harbors. The resulting &gt;100,000 litter particles per harbor indicate the existence of a problem. With 73%-74%, plastic particles are dominating. Existing legal and management frameworks explain the lack of plastic bottles and bags on sea floors in Germany and are one reason for the lower pollution levels. Items that indicate the role of untreated sewage water were not found. Harbor festivals seem not to be quantitatively relevant for open sea bottom pollution. Our method tends to underestimate the pollution level. Model simulations indicate that storms can cause litter reallocations and sediment cleanings. However, marina sea floor monitoring is recommendable, because it addresses pollution hot-spots, is cost-effective and takes place close to emission sources. Further, the effectiveness of land-based pollution reduction measures can easily be assessed.

Nowadays the preservation and restoration of historical building needs to be faced in accordance with a novel sensibility regarding environment to preserve the future generations. In this context, the scientific community is focusing on novel and sustainable materials and techniques allowing durability and mechanical performances and at the same time compatibility with the existing heritage. Alkali activated materials represent a great challenge to produce new materials starting from the existing ones with reducing consumption, emission of greenhouse gases and environmental impact. This study deals with the valorization of waste materials coming from demolition and construction activities in the manufacture of geocomposites suitable for restoration and conservation of historical heritage. In particular, waste from tuff sawing and brick grinding were used as raw materials, then the geopolymeric samples produced were characterized from physical-chemical and mechanical point of view in order to investigate their performance and evaluate their suitability as materials for historical buildings recovery. Brick waste based geocomposites resulted to be more compact than the tuff-based ones as showed by the higher density values and the lower values of open porosity and water absorption and as further confirmed by the trend of the mechanical performance. Moreover, experimental data showed that physical and mechanical properties of both bricks and tuff waste-based geocomposites, even with different waste content, are compatible with existing building materials and to all the traditional repairing products.

Leather waste was carbonized at 800 °C in inert atmosphere. The resulting biochar was coated in situ with polypyrrole nanotubes produced by the oxidation of pyrrole in the presence of methyl orange. The composites of carbonized leather with deposited polypyrrole nanotubes of various composition were compared with similar composites based on globular polypyrrole. Their molecular structure was characterized by infrared and Raman spectra. Both conducting components formed a bicontinuous structure. The resistivity determined by four-point van der Pauw method was monitored as a function of pressure applied up to 10 MPa. The typical conductivity of composites was of the order of tenths to units S cm−1 and it was always higher for polypyrrole nanotubes than for globular polypyrrole. The conductivity decreased by 1–2 orders of magnitude after treatment with ammonia but still maintained a level acceptable for applications operating under non-acidic conditions. The composites were tested for dye adsorption, viz. cationic methylene blue and anionic methyl orange, using UV-spectroscopy. The composites are designed for the future use as functional adsorbents controlled by the electrical potential.

The growing population with changing consumption patterns in developing countries is causing significant challenges with regards to solid waste management. Plastic wastes are particularly problematic, with single-use plastics leaking into the environment, including the marine environment, at an unprecedented rate. Approximately 80 percent of ocean plastics come from land-based sources or about 8 million tons are dumped into the ocean every year. Thailand was identified as one of the top 10 countries ranked by mass of mismanaged plastic wastes, with more than 60,000 tons per year entering the ocean through multiple outlets, including rivers. In the environment, plastic wastes can be degraded into small sizes (less than 5 mm), called microplastics (MPs), which could contaminate the ecosystems and the food chain, including foodstuffs and water supply. Tap water samples collected from a water supply treatment plant and Academic Institutions 1 and 2 in central Thailand were found to contain MPs about 304 ±90, 270 ±109 and 386 ±102 particles/L, respectively. In addition, MPs concentrations of 211 ±70 and 122 ±60 particles/L were also found in drinking water samples collected from commercial bottled water and membrane filtration water, respectively. The MPs sizes of 0-50 µm were most abundant in both the tap and drinking water samples whose shapes were mainly fragments and fiber. These data indicated potential health risks to the people who consume these water sources, and recommendations for health impacts minimization were proposed.

Effective solid waste management is crucial for protecting public health and the environment. Global concentration on finding sustainable methods of handling waste continue to top the list of most governmental-related project checklists. This paper provides a case study on the management of municipal solid waste in the cities of Karlsruhe, Germany and Navrongo, Ghana as developed and developing countries respectively. This study aimed at comparing and drawing lessons from how these two different cities manage their solid waste. The waste management system in Karlsruhe prioritizes waste separation, recycling, and a pay-as-you-throw system has led to an efficient and sustainable waste management system that minimizes waste and protects the environment. Karlshrue's adoption of a continual developmental plan structure focused on integrated WM concepts is credited with safeguarding the long-term viability of waste management in the city. In contrast, Navrongo's waste management system faces several challenges, including inadequate resources and infrastructure, traditional waste disposal practices, and the lack of well-planned waste management strategies. To improve effective solid waste management systems in Ghana, a collaborative approach involving the government, local organizations, and the community is necessary. This can include investing in infrastructure, implementing waste separation and recycling programs, and educating the public on the benefits of sustainable waste management practices. Learning from successful models like Karlsruhe can help accelerate the development of sustainable waste management practices in Ghana, and ultimately protect public health and the environment.

Cemeteries can be compared to landfills since their leachate, also known as necroleachate, can be transported and pollute groundwater, surface waters, and soils. In Brazil, the cemeteries management is the responsibility of states and municipalities, to ensure that they do not generate negative environmental impacts and risks to public health. This article aims to discuss Brazilian sanitary-environmental legislation relating to cemetery waste management. Among the Brazilian states, half have sanitary-environmental legislation for cemeteries, and between the municipalities, only 19 have specific legislation. The legislation is broad and has many gaps, leading to environmental vulnerability and risk of contamination for the people who live in the surrounding area.

In the past years, consumers have increased their interest to buy healthier food products, rejecting those products with more additives and giving preference to the fresh ones. Moreover, the current environmental situation has made society more aware of the importance of reducing the production of plastic and food waste. In this way and considering the Food Industry need of reducing the food spoilage along the food chain, edible coating has been considered as an eco-friendly food packaging that can replace traditional plastic packaging providing an improvement in the product’s shelf-life. Edible coating are thin layers applied straightaway on the food materials’ surface, that are made of biopolymers that usually incorporate other elements, such as nanoparticles or essential oils, to improve their physicochemical properties. These materials must provide a barrier that can prevent the pass of water vapor and other gasses, the microbial growth, the moisture loss, and the oxidation, so the shelf-life could be extended. The aim of this review was to compile the current data available to give a global vision of the formulation process and the different ways to improve the characteristics of the coats applied in both fruits and vegetables. In this way, the suitability of compounds in by-products produced during the Food Industry chain were also considered for the edible coating production.

The feasibility of using zeolites, synthesized from components found in municipal solid waste fly ash (MSW-FA), as sorbents for the recovery of nutrients (nitrate and phosphate) and heavy metals is critically assessed in this review. The inherent drawbacks of utilising a highly contaminated, variable, and relatively Al- and Si-dilute source such as MSW-FA to synthesize zeolites are discussed, and different methods to extract and decontaminate zeolite precursor materials from MSW-FA are considered. Ways to synthesize tailored zeolites and how their properties as well as the operational conditions impact the adsorption of cations such as ammonium and heavy metals are summarized. The use of surface-modified zeolites to adsorb nitrate and phosphate is also reviewed. And subsequently, approaches to utilise directly or recover for reuse the adsorbed compounds are considered, discussing potential challenges and mitigating measures related to leaching of unwanted compounds from the zeolites. Moreover, the possibility to regenerate the adsorption capacity of the zeolites for multiple adsorption cycles is considered. In the final chapter of the review a more general discussion of the main challenges and existing research gaps is provided, giving directions for recommended studies.

Solid waste has become a tenacious issue worldwide. It has been increasing exponentially due to urbanization and the increase in the population. Since the twentieth-century technological revolution, there have been significant changes in the composition of solid waste. It poses significant challenges for waste management systems worldwide. Waste management is the process of handling waste right from its creation to its final disposal, including transport, collection, treatment, and monitoring. The present solid waste management (SWM) system is affected by unfavorable institutional, economic, technical, legislative, and operational constraints. Poor waste management is affecting ecosystems and human health, damaging our finite natural resources, impeding human economic progress, and harming people's quality of life. Now, researchers are concerned about the environment's degradation, a decline in quality of life, and risks related to waste management grow as the volume of solid waste. So, they are focusing on sustainable waste management practices which will be crucial for creating a cleaner and healthier environment for future generations. This chapter focuses on the concept of solid waste, its types, management, and its effect on the health of humans and the environment.

The circular economy (CE) has emerged as a viable alternative for tackling the problems caused by rising consumption, including solid waste (SW). The present study conducted a meta-analysis of research published between 2012 and 2022 on CE and solid waste management (SWM). A bibliometric analysis was used from the Web of Science (WoS) and Scopus databases. By studying the articles, we briefly discussed the connections between them and how one contributes to the evolution of the other. Some findings point to greater collaboration between Italy and Bolivia, followed by China and Malaysia. However, they move away from the traditional axes as the United States and Canada. In addition, it was found that the adoption of reuse and selective collection, in fact, allow the reduction of the volume of discarded materials. In this way, it was possible to conclude that a greater connection between CE and GRS makes it possible to optimize the useful life of landfills through the treatment of organic waste and recycling, to encourage waste picker cooperatives and selective collection programs, and to reduce the financial costs of the system as a whole, making it more durable and sustainable.

It is expected that due to the new UE regulation focus on waste management, managing kitchen waste will become more important in the future, especially in households. It is, therefore, crucial to develop user-friendly and odor-free containers to store kitchen waste. The study aimed to test the effectiveness of compost biochar in reducing noxious odors and volatile organic compounds (VOCs) released during kitchen waste storage. Varying quantities of compost biochar (0%, 1%, 5%, and 10%) were added to food waste samples and incubated for seven days at 20℃. VOCs released were analyzed on days 1, 3, and 7 of the storage simulation process. The results indicated that adding 5-10% of composts’ biochar to kitchen waste significantly reduced emissions in 70% of detected VOCs compounds. Additionally, Compost's biochar can be used to eliminate potential odor components and specific dangerous VOCs such as ethylbenzene, o-xylene, acetic acid, and naphthalene. A new composts’ biochar with a unique composition was particularly effective in reducing VOCs and could be an excellent solution for eliminating odors in kitchen waste con-tainers.

The effect of organic matter (OM) on soil P-sorption is controversial and needs to be more investigated. The dissolved organic matter (DOM) may be regarded as an influential component on P sorption in natural soils. However, despite the great need for renewable sources of available P and OM in agricultural soils, little is known about interaction between P and DOM in natural soil systems. To uncover if and how soil saturation with DOM derived from different types of abundant agricultural wastes (cattle manure, horse manure, biogas digestate, compost) affects the phosphate sorption, we examined P sorption process in control and DOM-saturated sandy soils. The results indicated that organic matter introduced with agricultural wastes did not always reduce P sorption, but certainly had an effect on impairing P fixation and thus may result in potentially greater P mobility in the soil, including P availability. Up to now, we cannot recommend any of the tested organic amendments to directly overcome the P fixation in arable soils.

Concrete is a heterogeneous material, one of the most widely used materials on the Planet and a major consumer of natural resources. Carbon emissions are largely due to the extensive use of cement in its composition, which contributes to 7% of global CO2 emissions. Extraction and processing of aggregates is another sources of CO2 emissions. Many countries have succeeded in moving from a linear economy to a circular economy by partially or fully replacing non-renewable natural materials with alternatives from waste recycling. One such alternative consists in partially replacing cement by supplementary cementitious materials (SCMs) in concrete mixes. Thus, the work is based on the experimental investigation of the fresh and hardened properties of civil engineering concrete, hereafter referred to as road concrete, in which, crushed river aggregate have been replaced with recycled waste aggregates of uncemented concrete and partial replacement of cement with a SCM material in the form of glass powder that improves the durability characteristics of this sustainable concrete. The microstructure and compositional features of the selected optimum composite has been also investigated by polarized light optical microscopy (OM) Scanning electron microscope (SEM) and X-ray diffraction by the Powder method (PXRD) for the qualitative analysis of crystalline constitutive materials.

Investigating the potential impact of composting and recycling waste on income distribution are crucial to promote a fairer and more sustainable fresh tomato supply chain (FTSC). Therefore, this study aims to explore the potential of gaining extra income from recycling tomatoes waste generated along the FTSC and to calculate the contribution of extra income from recycling tomato waste to reduce income inequality along the FTSC. Data were collected from 136 greenhouse tomato producers, 60 wholesalers, 18 exporters, 120 domestic retailers, 22 overseas retailers, and 3 recycling facilities in Türkiye. Marketing cost, absolute marketing margin, relative marketing margin and net profit margin were used when economically analyzing the FTSCs. Research results showed that the net profit share of the producer decreased associated with the increasing number of intermediaries. Research results also showed that revenue gained from composting and recycling of product loss and waste increased the welfare of greenhouse producer more than other supply chain actors. When taking into account the revenue from composting and recycling of wastes, producers increased their net profit by 9.85% at first FTSC, while that of second and third FTSCs were 8.29% and 9.21%, respectively comparing to the prevailing conditions. The contribution of extra revenue from composting and recycling of wastes to retailers was more comparing wholesaler and exporter. Retailers and wholesalers gaining from recycling in domestic FTSCs was more comparing to overseas one. Close cooperation between producers, wholesalers, exporters, retailers, and recycling facilities is essential for the effective implementation of waste recycling initiatives. Organizing the training and education programs focused on waste management can increase the extra income of producers and active intermediaries in FTSC from composting and recycling tomato wastes. Offering financial incentives, grants, or subsidies can encourage producers and other actors within the supply chain to adopt waste recycling practices. Continuous research and innovation are crucial in identifying and developing new technologies, processes, and strategies to minimize food loss and waste. Dominating fair-trade practices to ensure that all FTSC actors may balance the income distribution among FTSC actors.

Coffee processing generates a huge amount of waste which contains many natural products. Here, we report the discovery of a panel novel cell-penetrating and metal-ion binding microproteins designated coffeetide cC1a-c and cL1-6 from the husk of two popular coffee plants, Coffea canephora and Coffea liberica, respectively. Combining sequence determination and database search, we showed that the prototypic coffeetide cC1a is a 37-residue, eight-cysteine microprotein with a hevein-like cysteine motif but without a chitin-binding domain. NMR determination of cC1a revealed a compact structure that confers it resistance to heat and proteolytic degradation. Disulfide mapping together with chemical synthesis revealed that cC1a has a ginsentide-like, and not a hevein-like, disulfide connectivity. In addition, transcriptomic analysis showed that the 98-residue micrcoproten-like coffeetide precursor contains a three-domain arrangement like ginsentide precursors. Molecular modeling together with experimental validation revealed a Mg2+ and Fe3+ binding pocket at the N-terminus formed by three glutamic acids. Importantly, cC1a is amphipathic with a continuous stretch of 19 apolar amino acids, and which enables its cell penetration to target intracellular proteins, despite being highly negatively charged. Our findings suggest that coffee by-products could provide a source of ginsentide-like bioactive peptides that have potential to target intracellular proteins.

Genetic adaptation of Hermetia illucens (BSF) to suboptimal single sourced wastes can open new perspectives for insect production. Here, four replicate BSF lines were maintained on a single sourced, low-quality wheat bran diet (WB) or on a high-quality chicken feed diet (CF) for 13 generations. We continuously evaluated evolutionary responses in several performance traits to rearing at the two diets. Subsequently, we tested responses to interchanged diets, i.e. of larvae that had been adapted to low-quality feed and to high quality feed and vice versa to evaluate costs associated with diet adaptation. BSF were found to experience rapid adaptation to the diet composition. While performances on WB diet were always inferior to CF diet, the adaptive re-sponses were stronger to the former diet. This stronger response was likely due to stronger se-lection pressure experienced by BSF fed on the low-quality single sourced diet. The interchanged diet experiment found no costs associated with diet adaptation but confirmed diet adaptation for the larval biomass and insect frass traits for the WB diet treatment. Our results revealed that BSF can rapidly adapt to diet through evolutionary responses, which has potential to be utilized to produce lines tailored to specific diets.

Development of high nutritious bakery products with optimum utilization of food waste is a major challenge for food industries. Food waste is major challenge in an each country. The optimum utilization of food waste for sustainable development goal of country is important ant for growth of the nation. The aim of the present work is to prepare value-added composite flour mixed bread from wastes of fruit and vegetables. The composite flour was prepared in four formulations of Peel and Pomace Wheat Flour (PPWF), as PPWF1, PPWF2, PPWF3 and PPWF4. Compositing flour was blended by a mix of vegetable and fruits pomace powders and whole wheat flour. Indian gooseberry pomace powder, apple pomace powder, bottle gourd peel powder, and potato peel powder were used with whole wheat flour to make pomace and whole wheat flour compositions as PPWF1, PPWF2, PPWF3 and PPWF4. Broadly this work was divided into three phases, first phase has conducted nutritional and functional analysis on peel and pomace powders individually, which shows the significance of using them for our research work. The second phase works in the creation of composite flours with different composition ratios as discussed above as PPWF. This phase shows the nutritional and functional analysis of four composite flours. Out of these four flours, PPWF3 contained a good amount of fiber 8.16%, crude protein 3.18%, total phenolic content 14.48%, moisture 9.5%, vitamin C 13.64mg/100g, and total phenolic compound 14.48(mg/GAE/g) which are maximum and acceptable range values as compared to other three composite flours and the wheat flour-control group flour. Then in the third phase, the PPWF3 is used as a partial replacement ratio of wheat flour in wheat flour due to its high phenolic content, Vitamin C, and the richness of fibers. This composite flour is used to make bread dough, two samples G1 and G2 are made; out of which G2 offers better nutritional, functional, and sensory evaluations in comparison with refined wheat four bread is taken as a control group. Thus, such utilization of food wastes in bread making can generate a value of wastes and can improve nutritional attributes of bread, which may improve an individual’s health.

Pyrochlore oxides (A2B2O7) are potential nuclear waste substrate material due to their superior radiation resistance properties. We performed molecular dynamics simulations to study the structural properties and displacement cascades in ytterbium titanate pyrochlore (Yb2Ti2O7). We computed threshold displacement energy ( Ed ) and lattice constant ( ao) of Yb2Ti2O7. The effect of displacement cascades in Yb2Ti2O7 of recoils of energies 1 keV, 2 keV, 5 keV, 10 keV in different crystallographic directions ([100], [110], [111]) were studied. The number of defects is found to be proportional to the energy of incident PKA. Additionally, the Ed of pyrochlore is computed and it exhibits anisotropy. Furthermore, radiation damage in high-entropy pyrochlore (HEPy) i.e., YbYTiZrO7, YbGdTiZrO7 , Yb0.5Y0.5Eu0.5Gd0.5TiZrO7 were investigated and compared with Yb2Ti2O7. It was found that HEPy have a larger Ed as compared with Yb2Ti2O7 which exhibits characteristic of lower radiation damage resistance than HEPy. Our simulation proposed that HEPy alloys are more radiation resistant than individual pyrochlore constituents . This work will provide atomic insights in developing substrate materials for nuclear waste applications.

This scoping review examines global strategies and enterprises for sustainable solid waste management, with a focus on alternative landfilling approaches. The study collected and analyzed a significant number of documents from different regions, revealing Asia as the major contributor (for the collected documents) (48.7%), followed by North America (24.3%) and Europe (15.8%). Recycling emerged as the most effective alternative waste treatment method, representing 52.3% of the documented approaches, with industrial recycling (22.6%) and residential/non-residential recycling (20.2%) as prominent categories. Food waste was a significant concern across regions, constituting 21.4% of the collected documents. Composting was widely adopted (15.4%) due to its simplicity and benefits for gardening and soil improvement. Other methods like biogas extraction, reusing, raising awareness, incinerating, redistributing, reducing, and fermentation accounted for 13.1% cumulatively. The study highlights the need for tailored waste management solutions based on regional challenges and successful practices. Promoting recycling infrastructure, composting, and waste reduction approaches are crucial to achieving sustainable waste management aligned with SDGs. Collaboration and knowledge-sharing between regions are essential to improve inefficient waste management mechanisms. Integrating the findings into policymaking and industry practices can lead to a more sustainable future with reduced environmental impact.

Bitumen is produced from non-renewable natural resources, continuously deplete and intrigues researchers to look for alternative binders. Annually, tons of waste engine oil (WEO) and crumb rubber (CR) are discarded unsustainably and pose a significant environmental threat. Adding these industrial waste products to asphalt provides a safe and cost-effective way for their disposal and improves the bitumen's performance in parallel. This study uses various combinations of waste engine oil and crumb rubber with 60/70 penetration grade bitumen to produce a partially synthetic bitumen. Adhesion being one of the critical characteristics of the bituminous binder has been assessed using the bitumen bond strength test along with physical and rheological properties. Results showed that waste engine oil with crumb rubber inclusion increases penetration and decreases the softening point, viscosity, complex modulus, and bonding strength. Additionally, polyphosphoric acid (PPA) in smaller dosages was also incorporated into the optimum percentage of CR + WEO to improve the properties of the binder. The results confirm that binder modification with waste engine oil and crumb rubber can be more effective with PPA. It is concluded that 35% of waste can replace the virgin binder giving a cost-effective and environmentally friendly solution.

COS production is carried out enzymatically using chitosanase, but this process is expensive. Production costs can be reduced by using crude enzyme chitosanase, and the resulting COS has depolymerization &lt; 20 and molecular weight &lt; 3900 Da. Sources of crude enzyme chitosanase come from the soil, sediment, and fishery waste. Chitosanase is produced from bacteria and molds isolated from the source or direct isolation process for extracellular enzymes, especially from fishery waste. Microorganisms in the soil produce chitosanase as a biocontrol and self-defense agent. Bacteria and molds have been isolated, including Bacillus cereus, Bacillus mycoides, Paenibacillus sp., and Penicillium janthinellum. Fishery waste, especially parts of the digestive tract, is a source of chitosanase because of its relation to its nature and food, such as small fish, frogs, and several types of crustaceans. In addition, fishery waste can be used as a carbon and nitrogen source (C/N) in microorganism culture media. The chitin content becomes a stimulant for the synthesis of chitosanase by microorganisms. Crude enzyme chitosanase has an active site that hydrolyzes chitosan by breaking glycosidic bonds and producing glucosamine units (GlcN) and N-acetyl glucosamine (GlcNAc). This mechanism can take place through two events, namely inverting and retaining. Crude enzyme chitosanase can break glycosidic bonds, especially with the same groups, for example, bonds between glucosamine or N-acetyl glucosamine. The COS produced is of the partially acetylated COS (paCOS) type, which still contains an acetyl group. The degree of deacetylation is a significant factor in the resulting COS product, COS with the fully deacetylated COS (fdCOS) type of chitosan with a high degree of deacetylation. Other factors to consider are the raw material of chitosan, the incubation time, the screening process, and the production of microorganism cultures.

The production of photovoltaic modules is increasing to reduce greenhouse gas emissions. However, this results in a significant amount of waste at the end of their lifespan. Therefore, recycling these solar panels is important for environmental and economic reasons. However, collecting and separating Crystalline silicon, Cadmium Telluride, and Copper indium gallium selenide panels can be challenging, especially in underdeveloped countries. The innovation of this work is to develop a process to recycle all solar panel waste. The dissolution of all metals is studied through the leaching process as the main step of the flowchart. In the first step of leaching, silver can be recovered 98% by 0.5 nitric acid. Then, the second and third step involves the use of glycine for base metals dissolution, followed by the leaching of valuable metals with hydrochloric acid. The effect of parameters such as initial pH, acid concentration, solid/liquid ratio, and Hydrogen peroxide concentration are studied. The results show that Cu, Pb, Sn, Zn, Cd, In, Ga, and Se can be recovered until about 100% under optimal conditions. The optimal conditions for the dissolution of Cu, Zn, and Cd were the glycine concentration of 0.5 M, Temperature of 25 ˚C, the solid/liquid ratio of 10 gr/l, and 1% of Hydrogen peroxide. The optimized glycine concentration for the leaching of lead and tin was 1.5M. Indium and gallium were recovered to 100% by the use of 5M Hydrochloric acid, S/L=10gr/l, and T=45 ˚C. Separation of selenium and tellurium occurred by 0.5 M HCl at a temperature of 60 ˚C. Additionally, for the first time, a general outlook for the recycling of various end-of-life solar panels is suggested.

The fishmeal production industry is essential for providing protein for animal feed in the aquaculture sector. However, the industry faces challenges related to energy consumption and environmental sustainability. This study evaluates the energy efficiency and environmental benefits of waste heat recovery (WHR) technologies in a fishmeal production plant in Vietnam. Data were collected from the plant between 2016 and 2022, and a specific energy consumption (SEC) indicator and a comprehensive methodology were utilized. Implementing an economizer as a WHR technology resulted in a 55.5% decrease in SEC compared to the state before installation. The enhanced energy efficiency also translated to reduced energy consumption per output unit. Moreover, the economizer contributed to annual energy savings of 4,537.57 GJ/year and cost savings of $26,474.49. Additionally, carbon dioxide (CO2) emissions associated with producing one ton of fishmeal decreased by 58.37%. These findings highlight the potential for WHR technologies to improve energy efficiency and reduce the environmental footprint of fishmeal production. The study's results provide valuable insights for practitioners and policymakers in promoting energy efficiency practices and reducing environmental impact in the industry.

This paper examines the relationship between GDP per capita and waste generated in European Union countries, highlighting the importance of this relationship for understanding the environmental consequences of economic growth and formulating waste management policies. The analysis findings demonstrate that, in most cases, higher GDP is associated with higher amounts of waste, although there are exceptions to this trend. A smaller number of countries are also found where no such relationship exists. These are primarily high-income countries in the lower part of the EKC or countries in transition. Cluster analysis reveals regional differences in the relationship between GDP and waste that the economic factors and the level of development in the regions concerned can explain. Bulgaria is among the European countries with the lowest economic growth associated with a large amount of waste. The analysis, therefore, focuses on Bulgaria. The impact of GDP per capita, Human Development Index and Population Density on municipal waste in Bulgaria is studied. The aim is to identify significant relationships and dependencies between these factors and the amount of waste. Based on the results of multiple regression analysis and the findings from municipal waste management data in Bulgaria, specific actions are proposed for municipal waste management in the country. Recommendations are made for developing sustainable waste management policies and sharing best practices between regions.

Amidst the strong demand for wood-based products, and the clamor of environmental consciousness, more functional and green solutions arise to meet both of these goals. Pursuant to this, the study looked into the potential of a bio-waste taken from Cocos nucifera tree known as phellem—the tree’s outermost skin made of dead tissues, to be a main component of a new construction material. This study builds on existing research showing phellem is impermeable, buoyant, elastic, has a slow burn rate, and repels water during precipitation, which supports the hypothesis that phellem may be a potential substitute material for dry wall boards. To test this, three (3) formulations were developed as experimental setups to test the physico-mechanical properties of coconut palm phellem (COPAP): Formulation A (40% COPAP and 60% cement); Formulation B ( 25% COPAP and 75% cement); and lastly, Formulation C that was (10% COPAP and 90% cement). The study tested (1) which among these formulations exhibited the best physico-mechanical properties, then it (2) compared the formulations with common dry wall products available in the market, and subsequently, (3) identified the possible architectural applications of COPAP board as a new building material. Of the three setups, Formulation C exhibited the best physico-mechanical properties in terms of compressive and flexural strength, fire resistivity, and water absorption. It fared better than the particle board in terms of compressive strength, better than wafer and particle board in fire resistivity, performed best in the water absorption test, and was almost equivalent in flexural strength to fiber cement board. With these findings, the study concluded that COPAP board can be used for projects that entail a high number of interior partitions, such as offices, BPO firms and commercial stalls in shopping malls, etc. The findings were conclusive only for interior applications, as the results clearly suggest that the COPAP boards are not load-bearing. Future investigations may explore and assess other properties of COPAP boards like thermal and sound insulation, resistance to rot and other properties that may prove its competitive advantage as a construction material.

Pomegranate (Punica granatum L.) is well known for its high content in bioactives including polyphenols, flavonoids and tannins, which have been shown to exhibit a wide range of biological activity such as antioxidant, antimicrobial and anticancer effects. It is worth noting that the majority of these molecules are found in the peels (PP), which are usually disposed of after processing, causing a significant amount of waste, amounting to more than 3.6 million t/y. This work investigates MW-assisted extraction (MAE) in water for the recovery of antioxidants from PP, including the optimization of temperature and extraction times. The total phenolics, anthocyanin, flavonoid and tannin contents of the recovered extracts have been determined, as have their antioxidant activities, which were found to be 356.35 mgGAE/gextr., 303.97 µgCy3G/gextr., 37.28 mgQE/gextr., 56.48 mgGAE/gextr. and 1.43 µmolTE/gextr., respectively (according to the adopted reference). All results have been compared with those obtained using a conventional protocol. In addition, the potential for water recycling by means of nanofiltration downstream in optimized MAE has been investigated, leading to overall water reuse of approx. 75%. Energy consumption (20.92W/mgGAE) and the common green metrics, RME, E-Factor and PMI (PME), have been considered in evaluating the proposed PP valorization strategy. Finally, the biological activity of the main products has been assessed. The antimicrobial properties of the PP extracts against three Gram-positive and three Gram-negative bacteria, and their antiproliferative activity towards human cancer cells have been tested. The S. aureus bacteria was the most susceptible to the PP extracts. All tested products displayed antiproliferative activity in HeLa cells when higher concentrations were tested, with D-PP/NF being the most effective. This result was also confirmed in a clonogenic analysis, which generally indicated the possible anti-cancer activity of pomegranate peel extracts obtained using this green approach.

High-strength wastewaters from a variety of sources, including the food industry, domestic septage and landfill leachate, are often hauled to municipal wastewater treatment plants (WWTPs) for co-treatment. Due to their high organic loadings, these wastewaters can cause process upsets in both the WWTP’s liquid and solids treatment trains and consume organic treatment capacity, leaving less capacity available to service customers in the catchment area. A novel pre-treatment method, the Waste Activated Sludge-High Rate (WASHR) process, is proposed to optimize the co-treatment of high-strength wastewaters. The WASHR process combines the contact stabilization and sequencing batch reactor processes. It utilizes waste activated sludge from the municipal WWTP as its biomass source, allowing rapid start-up. Bench scale treatment trials of winery wastewater confirm the WASHR process can reduce loadings on the downstream WWTP’s liquid treatment and solids treatment trains. A case study approach is used to confirm the economic viability and environmental sustainability of the WASHR process compared to direct co-treatment using life cycle cost analyses and greenhouse gas emissions estimates.

The decentralized treatment of wastes is studied for an urban scenario considering a high-density population of 2500 inhab./km2. Food and garden waste were assumed to be treated in a co-digestion configuration using several mid-size digesters. In contrast biogas and digestate valorization were carried out in a centralized manner. Electricity and thermal energy were produced from this configuration, accounting for 1.3% of residential electricity demand and 3.2% of thermal demand when using double-turbocharged engines. However, the location of the treatment plants is a factor that may raise social discomfort. Rejection of locating the plant in specific sites close to residential neighbors, nuisance due to possible odor and gaseous emissions, and house market distortions are just a few of a long list of problematic aspects that may threaten the decentralized alternative. These factors are of great relevance and must be given a practical solution if the circular economic model is to be implemented by considering the insertion of waste streams into the production system and generating local energy sources and raw materials.

The edible portion of Cannabis sativa L. are the seeds. The seeds are generally used for the production of hemp oil, appreciated for the high percentage of α-linolenic acid. The waste obtained after seeds oil extraction, reduced in fine powder, is the subject of this study. Since hemp seeds are considered to be a source of many valuable bioactive compounds, the addition of hemp seed flour to durum wheat for making fortified bread could have an effect on the health of consumers. The aim of this study was to use variable percentages of hemp seed flour for the production of bread, and to determine the fortification impact on chemicals, texture, organoleptic characteristics, crumb color, changes in crumb texture, total polyphenols, free radical scavenging activity and amino acids contents. The rheological and chemical qualities of bread samples, obtained by using a durum wheat cultivar Ciclope fortified with defatted hemp seeds flours, were evaluated. The solid residue left after the extraction of the oil from seeds (generally thrown away as waste or added to feed) was shredded and sieved at 0.530 mm (Hemp 1) or 0.236 mm (Hemp 2). Samples of fortified breads were obtained by substitution of variable percentages of durum wheat flour with the two hemp flours (5%, 7.5%, and 10%). Fortified bread’s total phenolic content was in a range of 0.73±0.017 and 1.73±0.029 mg GAE/g and an-ti-radical scavenging activity was included in the range from 1.17±0.099 and 3.18±0.071mmol TEAC/100g, according to the increasing fortification. Comparison between bread made with Ciclope semolina and hemp flour fortified breads, showed a large increase in amino acid content in fortified samples ones. In particular, bread fortified with 10% Hemp 2 flour highlights a greater content of glutamic acid, tyrosine, proline and essential amino acids such as leucine and isoleucine, compared to the other samples with same percentage of substitution. The amount of hemp seed flour influenced the color of the crumb by increasing the yellow index from 18.24 (100% Ciclope) to 21.33 (bread with Hemp 2 flour at 5%).

Due to the growing demand for Medicinal and Aromatic Plants (PAMs), environmental risks associated with overexploitation and inadequate waste management are increasing. Since MAPs residues have a notable potential to be valorised, the implementation of Circular Economy solutions can play a central role in transforming waste management problems into economic opportunities and in responding to the growing demand for MAPs. Circular economy is viewed as a solution for fostering a sustainable system planet and positively contributes to the economy and society. A systematic review was conducted aiming to identify potential applications for the valorisation of MAP, under a sustainable waste management and circular economy approach. A total number of 47 studies were analysed and it was verified that MAPs residues can be valorised for energy purposes, crop management and applications in chemical, food, pharmaceutical, cosmetic industries, among others. Despite the wide range of possible applications, to promote a progressive implementation of circular economy strategies by the industry, further investigation is needed regarding the development of more efficient techniques and technology to develop value-added products and the assessment of sustainable performance in empirical investigations, considering both economic and environmental indicators.

In the past few decades, the use of agricultural waste has been increasing due to the increasing demand for sustainable materials. This paper aims to review the significance of agricultural waste as a type of wealth and its potential as an alternative material in the composite field. It was found that many agricultural wastes had been utilized in various production of ecological products. The review discusses the physical, mechanical, and chemical properties of the natural fibers made from agricultural waste and the use of Pineapple Leaf Fiber Reinforced Composite to manufacture UAVs (Unmanned Aerial Vehicles). The extracted waste fibers’ physical, mechanical, and chemical properties show that these agricultural wastes can produce better advanced composite materials suitable for structural applications. The use of pineapple leaf fiber in Unmanned Aerial Vehicles manufacturing has the potential to revolutionize this industry and contribute to a more sustainable future.

Indonesia's government anticipates waste problems by managing them through a large number of waste reduction programs. From a governance perspective in Indonesia, it is known that actors from diverse governmental levels and across sectors are involved in waste management, and their involvement largely depends on their institutional goals and problems. Hence, they are expected to coherently collaborate together by developing and implementing sustainable instruments and resources for improving waste management problems. However, it is necessary to understand how supportive and restrictive the governance of waste reduction programs is to encourage successful trash reduction. This study is designed to evaluate and examine the application of Community-Based Solid Waste Management (CBSWM) in Makassar. In this research, The Governance Assessment Tool (GAT) was applied to analyze the governance context of the waste reduction programs in Makassar qualitatively. From the assessment, contexts can be described as either supportive or restrictive of the processes of implementing public policies on waste management. As a result of such an assessment, this study shed light on some opportunities to improve the governance of waste management implementation's impact on reducing waste in Makassar, South Sulawesi, Indonesia. The conclusion of this study depicts that the most important actors are affiliated with the local government and the community. Moreover, this study shows that the assessment of contextual governance is predominantly restrictive.

Encapsulation is a valuable strategy to protect and deliver anthocyanins (ACNs), phenolic com-pounds with outstanding antioxidant capacity but limited stability. In this study, coacervation was used to encapsulate an ACNs-rich red cabbage extract (RCE). Two agri-food by-products polymers, whey protein isolate (WPI) and apple high-methoxyl pectin (HMP), were blended at pH 4.0 in a specific ratio to induce the formation of nanoparticles (NPs). The process optimisation yielded a monodispersed population (PDI < 0.200) of negatively charged (-17 mV) NPs with an average diameter of 380 nm. RCE concentration influenced size, charge, and antioxidant capacity in a dose-dependent manner. NPs were also sensitive to pH increase from 4 to 7, showing a progressive breakdown. The encapsulation efficiency was 30%, with a retention of ACNs within the polymeric matrix being influenced by their chemical structure: diacylated and/or C3-triglucoside forms were more efficiently encapsulated than monoacylated C3-diglucosides. In conclusion, we report a promising, simple, and sustainable method to produce monodispersed NPs for ACNs encapsu-lation and delivery. Evidence of differential binding of ACNs to NPs, dependent on specific ac-ylation/glycosylation patterns, indicate that care must be taken in the choice of the appropriate NPs formulation for the encapsulation of phenolic compounds.

The demand for improving the nuclear waste management has since long been identified as one of the major hurdles for widespread use of nuclear energy. Nuclear waste management, through partitioning and transmutation (P&T) has been researched since the 1990ies with partitioning being a pre-requisite for the process. Recently, an innovative approach of reactors directly operating on spent nuclear fuel, iMAGINE, has been proposed which could deliver on the aims of P&T as a side effect to more efficient nuclear energy production in the future. The results shown here confirm that it is possible to achieve the aims of P&T without prior partitioning, but it is certainly less efficient since the high concentration of MAs, required for efficient burning, are impossible to obtain in a short operational time. The proposed nuclear waste management approach will be a long-term effort when it is accomplished without partitioning/separation technologies. However, none of the analyses contradicts this effort – the key points are a) when the technology for treating the waste is possible and reliable, the time horizon will not be a major concern b) the waste management is now intrinsically linked with energy production instead of requiring dedicated costly facilities, delivering a promising economic basis c) the waste management is now associated with long-term energy production and massively improved resource utilization. In summary, the objectives of P&T are achievable without prior partitioning – this is a ground-breaking result. However, the approach will require continued nuclear energy production for a very long time. In case of a nuclear phase-out decision, a much more efficient transmutation scenario would have to be envisaged as already discussed several years ago for Germany.

Solid spent nuclear fuel from nuclear power plants has 3.4% fission products (80-160amu), contributing to over 99.8% radioactivity. On the other hand, liquid high-level radioactive waste (HLRW) from spent fuel reprocessing has 98.9% bulk elements (0-60amu) with 0.1% radioactivity. A separation mechanism on the mass categories as groups presents unique opportunities in managing HLRW for the long term with a considerable cost reduction. This paper proposes a thermal plasma-based separation system incorporating atmospheric pressure plasma torches for HLRW mass separation into low-resolution mass groups. Several engineering issues, such as waste preparation, waste injection into the plasma and waste collecting after mass separation, need to be addressed. Using COMSOL Multiphysics simulation, the generic system can be studied using noble gas mass separation and further analyze the mass filter capabilities. This paper provides the history of plasma-based mass separation. Functional modelling of a thermal plasma mass separation system is proposed under atmospheric pressure. Finally, aspects of mass separation simulation using noble gas Argon and Helium inside the plasma mass separation system were studied in COMSOL Multiphysics.

Waste management is an unavoidable technological operation in the process of raw material extraction. The main characteristic of this technological operation is the handling of large quantities of waste material, which can amount to several hundred million cubic metres. Working with this amount of material usually requires high-capacity systems for excavation and loading, a large fleet of trucks for haulage, construction, and maintenance of a complex roads network, use of a significant area of land in order to achieve the required capacities, etc. At the same time, this operation must comply with all administrative and environmental standards. Therefore, optimising waste rock management (particularly haulage and dumping) has the potential to significantly improve the overall value of the project. This paper presents a hybrid model for the optimisation of waste dump design and site selection. The model is based on different mathematical methods (genetic algorithm, analytic hierarchy process and heuristic methods) adapted to different aspects of the problem. The main objective of the model is to provide a solution (in analytical and graphical form) for the draft waste dump design, on the basis of which the final waste dump design can be defined.

Millions of tons of wool waste are produced yearly by textile industries, which may become a serious environmental hazard in the near future. Given this concern, it is crucial to explore strategies to reduce the amount of wool waste generated worldwide and adopt more sustainable practices for dissolving and regenerating wool keratin (WK) from textile waste. Most traditional methods involve the use of expensive, toxic, harmful, and poorly biodegradable compounds. To overcome these limitations and facilitate the reuse of wool waste through a cascade valorization strategy, researchers have started testing the use of deep eutectic solvents (DES) as a more sus-tainable and eco-friendlier alternative for WK dissolution and regeneration. In this study, the potential of two different DES mixtures, Choline chloride (ChCl): Urea and L-Cysteine (L-Cys): Lactic acid (LA), was explored for dissolving wool waste. Subsequently, the obtained gels based on DES-WK were blended with polyvinyl alcohol (PVA) in different ratios to produce nanofibers using the electrospinning technique. The effect of pH and the properties of the electrospinning solutions, namely electrical conductivity and viscosity, on the morphology of the gel solutions were evaluated. Moreover, the morphological features of the produced gel-based electrospun PVA/DES-WK nanofibrous membranes were analyzed using scanning electron mi-croscopy (SEM). Additionally, the PVA/L-Cys: LA DES-WK, which proved to be the most effective DES mixture for fabricating WK gel-based nanofibers, were characterized through Fourier transform infrared spectroscopy (FTIR) and tensile tests. Furthermore, their antioxidant and an-timicrobial abilities were evaluated. The results obtained revealed that this approach to valorize textile waste offers a unique avenue for the development of sustainable functional materials with potential applications in various biomedical and industrial fields.

Waste management is a significant issue that Indonesia must face. The presence of waste will always exist as long as life continues. One of the main challenges in waste management is the proper separation of organic and inorganic waste. As a solution to address this issue, the Ministry of Environment has made efforts to develop Waste Banks. However, it also creates new problems related to manual data collection, lack of monitoring by the community in implementing waste management activities, and a lack of specific reports regarding waste management conducted by officers. We propose the creation of a website using the Agile Development SDLC method. This website involve several steps and incorporate functions for data digitalization and expedited data collection, such as the addition of QR Code functionality, Monthly Reporting Function, and enhanced data security. The method used in this research is Agile Development. The application has been developed with a user-friendly interface and the latest web development technologies to ensure smooth performance. Overall, the web-based application for organic and inorganic waste using Laravel is an important step to promoting sustainable waste management practices.

A tumbler screen type residual film–impurity mixture wind separator as a key equipment for secondary utilization of farmland residual film. During the working process, the proportion of impurities in the separated waste mulch film intermittently increases, resulting in poor working stability of the device, which may hamper long-term operation. In this study, the material inside the separation unit was continuously monitored, and the main factor affecting separator per-formance was determined to be the challenges in the effective depolymerization of some residual film–impurity mixtures. The principles of agglomeration and depolymerization of the residual film–impurity mixtures were analyzed using computational fluid dynamics (CFD) and discrete element method (DEM) flow-solid coupling simulation methods. The key factor affecting the disaggregation of the mixture was the collision force between the residual film–impurity mixture and the trommel screen. The collision force was maximum when the residual film–impurity mixture first collided with the trommel screen when it was fed into the separation device. As determined by force analyses, the key factors affecting the collision force of the process were the material feeding amount and the structure of the inlet. Furthermore, simulations were carried out for different inlet structure forms; the evaluation index was the maximum collision force of the residual film–impurity mixture agglomerate on the trommel screen. The best disaggregation effect was obtained with a square feed inlet and at a feeding rate of 202 kg/h. A prototype was built using these specifications for verification. The average value of the ratio of impurities in the re-sidual film was 6.966%, the coefficient of variation was 7.38%, and the dispersion of statistical results was small. The ratio of impurities in the residual film was kept constant during the con-tinuous operation of the wind separator. Thus, this study analyzed the agglomerate disaggregation process and provided theoretical insights for deter-mining the optimal structures of the inlets of various cleaning devices and the feeding volumes.

Reductive leaching in the Bayer cycle using of iron (2+) allows Al extraction to be significantly increased by magnetization of Al-goethite and Al-hematite. However, the use of expensive iron (2+) salts or iron powder as a source of iron (2+) leads to a significant increase in production costs. In this work, the feasibility of a new method, the reductive leaching of bauxite using an electrolysis process, was investigated. Reduction of iron minerals of boehmitic bauxite in both Bayer solution and purely alkaline solutions were carried out. Experiments were performed using a plate cathode and a bauxite suspension in alkaline solution, as well as using a bulk cathode with a stainless-steel mesh at the bottom of the cell as the current supply. During the electrolysis process, the potential of the cathode relative to the reference electrode was measured as a function of current at different concentrations of solid (100-300 g L–1) and suspension temperatures (95-120 °C). It is shown that the current efficiency using suspension and plate cathode with the predominant deposition of Fe doesn’t exceed 50% even with the addition of magnetite to increase the contact of solid phase with the current supply. With the use of a bulk cathode, the reduction of iron minerals leads predominantly to the formation of magnetite with the efficiency of using electric current more than 80%. As a result of preliminary desilication and electroreduction it is possible to extract more than 97% of Al from bauxite, and to increase the iron content in the bauxite residue to 57-58%.

The dolomite dust-emulsified asphalt composite with excellent mechanical properties was successfully prepared using alkali activation. The effects of different alkali concentrations and emulsified asphalt contents on the mechanical properties of the materials were studied. The mechanical properties and microstructure of the composites were analyzed using compressive strength tests, bending strength tests, and SEM characterization. The experimental results show that the specimens have excellent mechanical properties: the 7-day compressive strength can reach 76.67 MPa, and the bending strength is about twice that of silicate-based geopolymer-emulsified asphalt composite. With an increase in emulsified asphalt content, the compressive strength of the samples decreases, while the bending strength increases first and then decreases. When the emulsified asphalt content is 1%, the bending strength of the sample is up to 28.81 MPa, which is 25% higher than that of the sample without emulsified asphalt. This indicates that an appropriate emulsified asphalt content can play a toughening role in the system, providing a new idea for designing high-toughness alkali-activated materials.

The extensive utilization of rebar during the construction of the project generates immense rebar waste, leading to increased construction costs and significant greenhouse gas emissions. Various approaches have been explored focusing on the minimization of rebar-cutting waste, such as optimizing cutting patterns, lap splice position, and special-length rebar utilization. Nonetheless, reducing rebar usage by minimizing the number of splices remains uninvestigated. In response to these issues, a two-stage optimization algorithm was developed, prioritizing special-length rebar to achieve near-zero rebar-cutting waste of less than 1% and concurrently reduce rebar usage, thereby promoting sustainable construction practices. The two-stage algorithm presented in this study involves the optimization of the lap splice position for the continuous rebar with a reduction of splices number. Furthermore, it integrates a special-length minimization algorithm for the additional rebars. Applying the algorithm to beam structures in a small-sized factory building project led to a notable reduction of 29.624 tons of rebar, equivalent to 12.31% of the total purchased quantity. Greenhouse gas emissions were reduced by 102.68 tons, and associated costs decreased by USD 30,256. A rebar-cutting waste of 0.99% which is near zero was achieved. These findings highlight the significant potential of the proposed algorithm in reducing rebar waste and facilitating sustainable construction practices. In addition, the application of the proposed algorithm in reinforced concrete construction projects will amplify the associated advantages accordingly.

The volatile fatty acids (VFAs) productions, as well as particulate organics decomposition, soluble chemical oxygen demand (SCOD) yield, and the VFAs production pathways, of mesophilic and thermophilic anaerobic fermentation were investigated. Batch experiments showed that the decomposition rate of volatile suspended solids (VSS), particulate carbohydrate (P-C) and particulate protein (P-P) followed the first-order kinetic model at different temperature. However, the intermediates， accumulated in the process of protein or carbohydrate digestion had a more significant inhibitory effect on the production of VFAs during the mesophilic anaerobic acidification process. Thermophilic fermentation led to more accumulation of VFAs compared to mesophilic fermentation. Then 13C stable isotope labeling experiment demonstrated that, acetic (HAc), propionic (HPr) and butyric (HBu) could be produced from carbohydrate and protein digestion, but valeric (HVa) was only generated from the degradation of protein. Finally, the possible pathway of HVa synthesis was proposed.

The use of food waste disposers in gastronomical facilities influence the municipal wastewater composition. Ground food waste poses problems in the operation of the sewerage network and generates high electric energy consumption in wastewater treatment plants (WWTP). The study aimed to determine, for five towns with a PE of 4,000 to 220,000, the volumes of catering waste discharged to the WWTPs. The towns differed in the number of inhabitants, beds in hotel and catering places. The calculations were made based on data received from the operators of WWTP. The pollutant concentrations in 2019, were compared with data from the "pandemic" year - 2020. The loads of catering waste entering the sewerage system in 2019 ranged from 32.7 to 1062 tons. In town with the largest tourist base, the BOD value in 2020 accounted for 62.3% of 2019 value. In the largest town, the annual energy consumption for food waste treatment could be up to 2,539,770 kWh. If the waste was fermented, it could be obtained up to 1,376,650 m3 of methane. There is a strong need for implementing a collection system for food waste from catering facilities and its fermentation to produce methane, which can be used for energy purposes.

Waste-to-Hydrogen (Wahh) is a process of converting waste into hydrogen gas through various methods such as thermal conversion, biological conversion, and chemical conversion. This process not only helps in managing waste but also provides a clean source of energy as hydrogen is a renewable energy source that produces zero greenhouse gas emissions during combustion. Wahh has the potential to provide a sustainable solution for energy generation and waste management in the current scenario of globally increasing energy demands. This study aims to examine the properties and energy efficiencies of various renewable fuels including fuelwood, biogas, biomethane, and biohydrogen with a specific focus on differentiating the characteristics of biohydrogen. The paper explores the emerging concepts of waste-to-hydrogen microgrids, biohydrogen refineries, biohydrogen prosumer networks, and a biohydrogen circular economy, as well as Public-Private-People Partnerships (4Ps) and the hydrogen-centric renewable energy revolution, which are taking shape in industrialized countries. The study presents a comprehensive feasibility analysis of these concepts in the context of Nepal. The results of this research will provide valuable insights into the potential for adopting these innovative technologies in Nepal and will contribute to the development of a sustainable and efficient energy system.

In order to reduce the environmental damage caused by coal waste landfills, it is necessary to look for rational ways of their management. One of the methods of their development may be the creation of soil-like substrates. The aim of the study was to assess the properties of soil-like substrates from coal mining waste with a varied share of sewage sludge and waste mineral wool. The evaluation of the properties of the substrates was carried out in a pot experiment. The properties of the substrates and their yield potential were determined. Coal mining waste as a substrate, compared to anthropogenic soil, was characterized by: significantly higher sorption capacity, content of alkaline cations and pH, significantly higher content of organic carbon, nitrogen and assimilable forms of K and Mg, and lower content of assimilable P. The substrates enriched with sewage sludge showed: significant increase in the content of organic carbon, nitrogen and assimilable forms of P and Mg, optimization of sorption properties. Extending the composition of substrates with mineral wool resulted in further improvement of their properties. Yields of plants grown on coal mining waste were significantly lower than on anthropogenic soil. Substrates with sewage sludge and mineral wool had a significantly higher yield potential.

This study revealed the synthesis of cross-linked chitosan/Citrus reticulata peel waste (C/CRPW) composites that could be used as low-cost and green bio-adsorbents for the removal of Congo red (CR) dye from aqueous solutions. C/CRPW composites containing different amounts of Citrus reticulata peel waste (CRPW) and chitosan were prepared and cross-linked with glutaraldehyde. The composites were characterized by FESEM, FTIR, and BET. The C/CRPW composites as a new type of bio-adsorbents displayed superior adsorption capability toward anionic CR molecules and the adsorption capacities increased by incorporation of CRPW. Effects of different ambient conditions such as contact time, pH, adsorbent dosage, initial adsorbate concentration, and temperature were fully studied. The conditions which obtained 43.57 mg/g of the highest adsorption capacity were conducted at pH 4, initial concentration of 100 mg/L, adsorbent dosage of 2.0 g/L, and contact time of 24 hours at 328 K. The adsorption data was found to follow the pseudo-second-order kinetic model and the Freundlich isotherm model. According to the findings of this investigation, it was observed that the C/CRWP composites can be used as adsorbents due to their advantages of simple preparation process, environmentally friendly, renewable, efficient, and low-cost.

Currently, the design of the concrete mix is an important part of the environmental problem. In front of this question, engineers face a major challenge that is addressed in two ways. On one hand, how do they use its component materials to improve its mechanical properties, on the other hand how do they use less polluting materials? Hence, in an environmental and economical view, laboratory tests were carried out on samples of concrete reinforced with smooth steel fiber extracted from the waste tires, in order to assess its impact and to prove its mechanical feasibility for these purposes. Consequently, laboratory results have shown satisfactory improvement in the behavior of concrete under compression loads in the elastic stage and an increase in ductility and toughness of the matrix in the plastic stage. Besides, taking into account the discontinuity and the structural disturbances observed during the loading of samples in the post-elastic state, a method has been proposed to calculate "the effective toughness and toughness Index of fiber concrete; on the other hand, this method has helped to better optimize length and slenderness of fibers for better use of this recycled material

Cigarette butts (CBs) are the most diffuse waste in the world, often abandoned in the environment without proper disposal. They are dangerous because of the numerous harmful chemicals poten-tially released in the environment. There are, in literature, several technological options for CB recycling, but some critical concerns could affect their effectiveness due to the quality and quantity of CB litter collected in the proper way. The present paper focuses on policy framework social behavior, waste collection and transport and technological processes. The Extended Producer Responsibility scheme for CBs is proposed at European level as an action to tackle CB litter and encourage sustainable product development. The CB waste collection and transport is a key step for bringing CB to the recycling process. The main concern is the small quantity of CBs collected: 0.06 % of the municipal waste and 0.18 % of the unsorted waste in the administrative area of Pe-rugia. Another crucial issue is the need for behavioral interventions to increase education and awareness of smoker citizens, addressing the discrepancy between smokers’ behaviors and beliefs.

The anaerobic digestion (AD) of rumen residues and wheat straw in different proportions of inoculum (66.67, 50, 33.33 %V/V) to substrate and their co-digestion potential have been exhaustively studied in this research. It explores variation of feedstock characteristics such as biodegradability and methane potential during AD and anaerobic co-digestion (ACoD) of rumen residues (RR) with wheat straw (WS), under mesophilic conditions. Comparative performance was made with a organic load rate of 18 gVS/L (with 2:1, 1:1 and 1:2 g/g VS of inoculum to substrate). Among different kinetic models studied (modified Gompertz model, transfer model and logistic function), the AD and ACoD of substrates showed better fit to Gompertz model (R2: 0.977–0.997) indicating variation in lag phase and methane production rate depending on the substrate characteristics. During AD, the methane yield improved as the inoculum ratio increased, however, there was no significant difference in ACoD yield from RR to WS for the inoculum to substrate ratios studied, due to the synergistic effect as a result. of greater biodegradability and optimal conditions (such as the C/N ratio). A comparison of methane generation means indicated that maximum methane production can be achieved by mixing rumen residue (75 %) and wheat straw (25 %) with a C/N ratio of (38.15).

Valorization of food and fruit wastes has the potential for the production of sustainable energy and biochemicals. Approximately 70% of the weight of the original jackfruit (Artocarpus heterophyllus L.) fruit is lost during processing as waste in the form of peeled skin and core, both of which have not been utilized and, thus contribute to disposal as well as pollution issues. The major components, cellulose, and hemicellulose, can be biologically transformed easily into bioenergy sources like ethanol, methanol, and butanol; valuable phenolics and biotechnological products like pectin, citric acid, bromelain, ferulic acid, and vanillin; and many other products. These residues can also be utilized as essential sources for the biological transformation process leading to the production of numerous products with added value, such as phenolic antioxidants, phenolic flavor compounds, and organic acids. Thus, the value addition of jackfruit waste can support the sustainable solution towards food and nutritional security. In this way, zero waste can be achieved through novel biorefineries which are critically highlighted in this paper. Furthermore, novel technologies for the conversion of jackfruit wastes are summarized with recent findings.

Transitioning towards net zero emissions is critical in the chemical and process industries to combat climate change and ensure environmental sustainability. Key focus areas of this review include the reduction of carbon emissions, the efficient utilization of energy resources, and the adoption of sustainable practices. Cutting-edge technologies such as biomass utilization, biotechnology applications, and waste management strategies are crucial in achieving this transition. Industries, including cement production, encounter unique challenges in their quest for sustainability and must actively seek innovative solutions to mitigate their carbon footprint effectively. The role of hydrogen as a clean fuel and its potential to revolutionize the chemical and process sectors is also discussed. The European Green Deal and Sustainable Development Goals (SDGs) are significant for the chemical industry. They provide a clear roadmap and framework for promoting sustainability, driving innovation, and reducing the industry's environmental impact. By aligning with these initiatives, the chemical industry can enhance its competitiveness, contribute to societal well-being, and foster collaboration across sectors to achieve shared sustainability objectives.

In this study, the gravimetric characterization and analysis of the solubilized extract of the organic fraction of Urban Household Solid Waste (RSDU) from the municipality of Belém do Pará was carried out in order to obtain the composition of the collected materials and the characteristics of the liquid resulting from the solubilization of these materials . The waste used to carry out this research was collected door-to-door, in which the points and neighborhoods served were determined through the sectorization of these locations and representative statistical sampling. For the sectorization of neighborhoods, family income values ​​were considered as the main parameter. After collecting the solid waste, the material was sent to the facilities of the Federal University of Pará (FUPa), where the waste was classified into paper, cardboard, tetrapak, rigid plastic, soft plastic, metals, glass, organic matter, waste toilets, fabrics and others. The organic fraction of solid waste was separated and sent to the drying, crushing and packaging processes. Subsequently, the solubilized extract of the organic fraction of solid waste was obtained, following the methodology recommended by NBR standard nº 10.006/2004, of the Brazilian Association of Technical Standards and the values ​​obtained were compared with Ordinance GM/MS nº 888/2021 and CONAMA Resolution nº 357/2005, in addition to results obtained by other authors. After carrying out the gravimetric characterization, it was possible to obtain the average proportions of 5.09% paper, 3.20% cardboard, 0.94% tetrapak, 3.58% rigid plastic, 9.97% soft plastic, 2.00% metals, 55.57% organic matter, 1.86% glass, 14.26% sanitary waste, 3.23% fabrics and 3.00% other waste. High values ​​of organic residues were found in the gravimetric composition, which can be explained by the collection method used and the high humidity of the organic solid residues. In the analyzes of the solubilized extract, values ​​of Hp (3.69 to 4.92), Turbidity (791 to 1,733 uT), Apparent Color (8,500 to 12,500 uC), True Color (6,000 to 14,000 uC), Total Dissolved Solids (5,330 to 8,040 mg/L), Total Nitrogen (201.80 to 359.90 mg/L), Ammoniacal Nitrogen (161 to 289 mg/L), Nitrate (10 to 40 mg/L), Total Phosphorus (52.30 to 166.80 mg/L) and Chemical Oxygen Demand (28,701 mg/L to 38,608 mg/L), in addition to other measured parameters, in which such information makes it possible to check the similarities of the waste solubilization conditions to that of leachates from landfills, in addition to not being in compliance with environmental and health legislation, demonstrating risks to the local environment and public health.

Modified aluminum slag (MAS) was applied as an adsorbent for Congo red (CR) prepared by the hydrothermal treatment of Ca (OH) 2. At 25 ℃, with a MAS dosage of 0.3g, initial CR concentration of 100 mg/L and initial pH=5, and the adsorption time was 40 min, the CR removal efficiency was 98.41%. The adsorption trend of CR conformed to the second-order kinetics, and the adsorption isotherm follows the Freundlich isotherm model. Compared with RAS, MAS has a larger pore volume and specific surface area. The mechanism of action of MAS on CR was the interaction between membrane diffusion and internal diffusion, and the adsorption rate during the membrane diffusion was the fastest.

In this paper an overview of waste materials in underground coal mines is presented, whereas waste materials can be of anthropogenic or geogenic origin. Complex interactions with mine water and waste materials take place, especially during mine water level rebound. Bearing in mind that under the increasing societal pressure most, if not all underground coal mines are going to be closed rather sooner than later, it is important to understand these interactions and to predict the composition and dynamics of mine water lever rebound in underground coal mines to prevent adverse effects to the environment, especially receiving waters and drinking water resources. The second part of this article focusses on the experiences gained in the Ruhr area, a closed underground coal mining region in Western Germany, where mine water rebound has been ongoing for decades. In this regard, the modelling program DMT-Boxmodel has been developed and applied to predict the hydrodynamics and hydrogeochemical development of the water rebound. As an example, simulation results of water rebound as well as solute and PCB transport in central province of Ruhr mining area are compared to the monitoring data, and predictions over 3 decades are given. The experiences gained in the mine water management in Ruhr area can be applied in mining areas worldwide.

The exponential growth in the consumption of electronics, in combination with the reduction in their useful life, leads to a significant increase in the volume of electronic material discarded. Printed Circuit Boards (PCBs) are modules composed of ceramic, polymer and metallic materials of high economic value and with a great potential for damage to biotic and anthropic environments when inadequately discarded. The aims of this work was to study the main environmental impacts and the efficiency of mechanical operations in the electronic waste recycling process in optimizing the concentration of metallic copper. For this, the samples obtained were characterized according to their morphology and chemical composition, and subjected to physical and mechanical treatments: dismantling, grinding, separation by granulometry, density and magnetic property. The environment impacts were estimated by the Life Cycle Assessment of the pre-treatment processes, associated with copper extraction operations in WPCBs. According to the results obtained, it is possible to infer that the NM +1mm Concentrated product presents in its metallic composition around 78% of copper, which contributes to the efficiency of the hydrometallurgical extraction processes. It is noteworthy that the Concentrated class represents about 14% of copper (wt) taking into account the amount of 3.789 kg of PCB waste input material. The potential for reinsertion of the dust in the material recovery process is highlighted, given that the chemical composition of this particulate has a significant presence of metals. In general, it was found that due to the higher concentration (wt %) of the sample being allocated in the range of - 0.15mm + 0.05mm, the elements Fe (18.30%), Si (10.73%), Ca (9.21%) and Cu (8.89%) stand out regarding the participation of the elemental composition of this fraction and also regarding the general composition of the sample. Furthermore, the generation of dust during the fragmentation process, can be associated with occupational respiratory diseases when not managed. About the Life Cycle Assessment, in seven of the nine categories evaluated, crushing and screening activities accounted for more than 90% of the recorded impact values. In general, it is estimated that in the pre-treatment phase be generated 15.4 kg CO2 eq.

Nano-emulsions of essential oils (EO) and their chemical constituents are promising raw materials for the ecological control of Tribolium castaneum. Curcuma longa Linn is a plant known for the properties of its rhizome which is used in food, health and hygiene products. Its leaves are by-products with no commercial value, but with unexplored bioactive volatile constituents. This study aims to evaluate the repellency of nano-emulsions containing the EO from leaves of C. longa or its three main chemical constituents against T. castaneum. The representative mixture of EO extracted in four different months showed p-cymene (26.0%), 1,8-cineole (15.1%) and terpinolene (15.5%) as major compounds. Nano-emulsions of EO (HLB 16.7), terpinolene (HLB 15.0), 1,8-cineole (HLB15.0) and p-cymene (HLB 15.0) were repellent at concentrations of 11 μg/cm2 (EO, terpinolene and p-cymene) and 1.1 μg/cm2 (1,8-cineole). The EO nano-emulsion droplet size increased linearly over time, remaining below 300 nm for 35 days and below 600 nm for 80 days. The EO nano-emulsion proved to be a green alternative to synthetic pesticides, as it was safe against the bioindicator Chlorella vulgaris. Terpinolene, 1,8-cineol and p-cymene were able to inhibit the enzyme telomerase from T. castaneum in an in silico assay, which may explain the repellency of these samples. This study provides ideas for the utilization of EO from leaves of C. longa as raw material of new environmentally friendly plant-derived nanobiopesticides.

To date, only a few studies focused on carbon monoxide (CO) production during waste composting; all targeted on CO inside piles. Here, the CO net emissions from compost piles and the assessment of worker’s occupational risk of exposure to CO at large-scale composting plants are shown for the first time. CO net emissions were measured at two plants processing green waste, sewage sludge, or undersize fraction of municipal solid waste. Effects of the location of piles (hermetised hall vs. open yard) and turning (before vs. after) were studied. Higher CO net emission rates were observed from piles located in a closed hall. The average CO flux before turning was 23.25 and 0.60 mg‧m-2‧h-1 for hermetised and open piles, respectively, while after – 69.38 and 5.11 mg‧m-2‧h-1. The maximum CO net emissions occurred after the compost was turned (1.7x to 13.7x higher than before turning). The top sections of hermetised piles had greater CO emissions compared to sides. Additionally, 5% of measurement points of hermetised piles switched to ‘CO sinks’. The 1-h concentration in hermetised composting hall can reach max. ~50 mg CO∙m-3 before turning, and &gt;115 mg CO∙m-3 after, exceeding the WHO thresholds for a 1-h and 15-min exposures, respectively.

The pandemic of Covid-19 has contributed to the increase of the number of cases of anxiety, depression, and stress, especially in vulnerable workers. The objective of this study was to analyze factors associated with mental health of waste pickers and street sweepers in Brasília, Brazil, during the Covid-19 pandemic. It was a cross-sectional cohort study with a quantitative approach. SRQ-20 test was used to assess mental health. The study sample included 886 workers: 601 street sweepers and 285 waste pickers. Of the total, 71 workers (8.0%) had SRQ-20 ≥ 7, which is equivalent to adverse mental health. The characteristics associated with adverse mental health were women (PR: 3.36; 95%CI:1.86;6.08), worker between 18-39 years old (PR: 2.19; 95% CI 1.32;3.65), waste pickers (PR: 1.65; 95%CI:1.01;2.70), worker who reported two (PR: 3.24; 95%CI:1.72; 6.12), three or more (PR: 4.73; 95%CI:2.40;9.32) health problems. For the symptoms, 17.05% of the people interviewed said they felt sad and 18.25% nervous, tense, and worried. Female waste pickers, young adults, with many health problems were more susceptible to adverse mental health and it doesn't just affect them, but also their families. Public policies are needed to protect these professionals so that they can work safely and establish early interventions to maintain these workers' mental integrity.

Concrete production requires a significant amount of natural resources, with aggregates comprising between 55% and 80% of the total volume. However, over-exploitation of natural aggregates has led to the exploration of alternative materials for use in concrete production. In this study, crushed hazelnut shells were investigated as a partial replacement for fine aggregate, addressing the problem of natural resource depletion and offering a second use for this important agricultural waste product available in Chile. Hazelnut shells were incorporated in percentages of 2.5%, 5%, and 10% by weight of sand for water-cement ratios of 0.4 and 0.5. The compressive strengths at 7 and 28 days and bending tensile strengths at 28 days were determined, alongside physical properties such as workability, temperature, air content, fresh density, and hardened density of the concrete. Our findings show that replacing 2.5% of the fine aggregate with hazelnut shells led to higher compressive strength at 28 days, exceeding the strength of the standard specimens by 9.5%, whereas replacing 5% of the fine aggregate led to the highest bending tensile strength, exceeding the resistance of the standard specimens by 3.5%. Moreover, the 0.4 w/c ratio consistently led to better results for both compressive and bending tensile resistances, with fewer and lower reductions in mechanical resistances compared to the standard mixture. Our results suggest that concrete mixes with hazelnut shells as a replacement for fine aggregate at a percentage of up to 2.5% can be used in constructive systems with compression strengths lower than 17 MPa, and mixtures with up to 10% hazelnut shell replacement can be used in structures with tensile bending stress requirements lower than 6 MPa. Overall, the use of hazelnut shells as a partial replacement for fine aggregate in concrete production presents an environmentally-friendly and cost-effective solution for the construction industry.

Agriculture has been experiencing a difficult situation because of limiting factors in its production, Natural biostimulants (NBs) have emerged as a novel alternative. This study reviews NBs produced through Solid-State Fermentation (SSF) from organic waste, focusing on the processes and production methods. The aim is to highlight their potential for improving agricultural productivity and promoting sustainable agriculture. Through a literature review, the effects of NBS on crops were examined, as well as the challenges associated with their production and application. The importance of standardizing production processes, optimizing fermentation conditions, and assessing their effects on different crops is emphasized. Furthermore, future research areas are identified, such as enhancing production efficiency and evaluating the effectiveness of SSF-produced NBS in different agricultural systems. In conclusion, SSF-produced NBS offers a promising alternative for sustainable agriculture, but further research and development are needed to maximize its efficacy and enable large-scale implementation.

Concrete contributes 8% of all global carbon emissions making the need to find substitute critical for environmental sustainability. Research has indicated the potential for recycled plastics to be used as concrete substitutes. This study extends existing research by investigating the use of polycarbonate (PC) in plastic sand bricks as a mechanical equivalent to concrete. PC has high compressive strength, durability, impact strength, thermal resistivity, clarity, fatigue resistance, and UV resistance. This work provides a method and mold to produce a matrix of sand-plastic sample compositions with dimensions adhering to ASTM D695 standard for compressive properties of rigid-plastic. Compositions of 0% (control), 20%, 30%, 40%, and 50% sand by weight were tested. Samples were tested for compressive strength until yield and stress-strain behaviors plotted. The results for 100% PC demonstrated an average and maximum compressive strength of 71 MPa and 72 MPa, respectively. The 50% PC and 50% sand composition yielded an average and maximum compressive strength of 71 MPa and 73 MPa respectively with an increase in compressive stiffness, and transition to shear failure resembling cement. With a composite density of 1.86 g/cm3 against concrete’s average 2.4 g/cm3, and a compressive strength exceeding commercial concrete demands of 23.3 MPa to 30.2 MPa, this lightweight alternative meets the strength demands of concrete, reduces the need for new construction materials, and provides an additional recycling opportunity for nonbiodegradable waste plastic.

Coffee production generates significant amounts of by-products, posing challenges for waste management in the industry. Recent research has revealed that coffee by-products are rich in bioactive compounds suitable to produce functional food ingredients and nutraceuticals. In this review, we explore biorefinery strategies for extracting and utilizing bioactive compounds from coffee by-products, including the production of bio-based chemicals and materials, as well as the extraction of phenolic compounds, antioxidants, and dietary fiber for food applications. We propose a stepwise approach for the development of functional food ingredients and nutraceuticals from coffee by-products, covering the identification of needs, comprehensive characterization, in vitro and in vivo research, unraveling the mechanism of action, food and nutraceutical formulation, sensory analysis, shelf-life stability, scale-up, randomized control trials, and biostatistic and bioinformatic integration. Additionally, we discuss the market potential, regulatory issues, and technological innovation surrounding the commercialization of coffee by-product-based products. Emphasizing the importance of regulatory compliance and sustainability in the coffee industry, this review highlights the potential of coffee by-products to be transformed from waste into valuable functional food ingredients and nutraceuticals, offering a promising avenue for waste reduction and promoting sustainability in the coffee industry.

This article seeks to strengthen efforts in technological developments based on the classification of PET plastic that positively impacts sustainable development and contributes to suitable solutions in collection centers in Mexico. Three experiment designs and machine learning tools for data processing were developed. For the experimentation, three factors were considered: the bottle's size, the amount of liquids inside the bottle, and the label on the bottle. The first experiment was to identify the distance of the sensor from post-consumer PET bottles. The second experiment was to determine the detection ability of the sensor with different levels of liquids inside the bottles, and the third was to determine the detection ability on the bottle labels. A digital lux meter on a microcontroller was developed to monitor illuminance on post-consumer PET plastic when it contains liquid as it passes through a conveyor belt for processing at an average rate of three bottles per second. With the implemented methodology, liquids were satisfactorily detected inside the transparent PET bottles when they had beverages between 25% and 100% of their capacity. Finally, this paper highlights that it is possible to implement an affordable design to identify bottles with liquids for collection centers.

Background: Food waste has been a major social problem in recent years. Annually, 1.3 billion tons of food is wasted worldwide. It is recommended that food waste should be reduced at every stage of production. By-products from food processing have high nutritional value; therefore their use in the design of new products is advisable. Methods: By-products from tomato processing (tomato waste-TW) and pepper (defatted pepper seeds-DPS, pepper placenta-PP) were used at a level of 10-30% to produce extruded pasta. The farinographic characteristics, chemical composition, cooking quality, and color of the pasta were studied. Results: The results showed a significant up to 27% increase in the protein content in the TW30 samples, compared to the control. The TDF content increased over five times in DPS30 and TW30 (27.99% and 25.44%). The amino acid composition of the pasta improved with the fortification, but failed to achieve the complete protein by FAO. The DPS30, PP20, PP30, and all TW samples can be considered high-protein products according to the EU definition (min. 20% energy from protein). Conclusion: Vegetable waste can be a valuable additive for improvement of the nutritional value of food. Their addition is part of the zero-waste trend, which has a positive impact on the environment.

Liability to prevent consequences of an unhealthy situation due to accumulating toxic and hazardous emissions caused by open dumping of municipal solid waste with increasing urbanization has necessitated a renewed thinking on waste disposal. Grate fired incineration systems were adopted by urban managements in past and present but with criticisms due to formation of air borne emissions. Improved combustion methods like fluidized bed are now propagated because of current requirements like efficient energy recovery potential, stricter emission norms, adaptability with urban growth, adaptability to co-firing with other waste like biomass, edible oil wastes or industrial effluent and integration with conventional energy generation. Such a comprehensive and futuristic approach is more sustainable for the community. Multi-criteria decision-making tool is used to identify the best technology option among grate combustion and fluidized bed combustion for disposing and energy recovery from waste. Ten different collection and disposal options involving two combustion methods, namely, grate combustion and fluidized bed method are considered. Utilization of the energy is done for three end uses, namely, power generation, water distillation and district cooling. Two different regions in Saudi Arabia are considered for this study under two types of scenario, namely with recycling and without recycling. The different options are prioritized based on their overall ranking using five major performance factors.

The production, processing of agricultural products results in massive generation of waste, which has an environmental impact. In current study on the node of valorisation of the processed waste, orange and banana peel waste are utilized for the production of biscuits. The fortified biscuits were analysed for proximate and sensory analysis. The fibre content of the fortified biscuits increases several folds. From the sensory score the proportion of biscuits with 7.5% and 10% has undesirable quality parameters, whereas up to 5% concentration all the parameters are more desirable. Fortifying biscuits with orange and banana peel powder may be an excellent source of dietary fibre and an enhanced valorisation technique.

Brewers’ spent grain (BSG) is an important waste produced in beer companies with a high po-tential to be transformed into commercial by-products. The present paper reports a forecasting technology study with the aid of bibliographic review and patent analysis tools aiming to in-vestigate the maturity of certain technologies, considering the use of BSG on a closed-loop bio-refinery and circular bioeconomy concept integrated into a brewery. To evaluate the possibili-ties of production of high-added value products in Brazil, it was presented an overview of BSG’s scientific, technological, and marketing products and applications. The comparison between numbers of articles versus patents shows that the solutions proposed by research articles are not being transformed into maturated viable technologies. The results suggest that there is a gap between the scientific research in the institutions and their applications in industry, which lead to the destination of the BSG for more economically attractive investments when compared to research in Brazil. Ultimately, from the carried-out analysis, it was possible to propose a brew-ing process connected to the biorefinery system, showing the possibility to the newly arising brewery industries.

Biorefineries convert biomasses in bioproducts and they contribute to transition to the circular economy. In this way it will be avoiding the penalty associated with generating a lot of waste. The first step in the obtention chain of bioproducts consists of the high value added products extraction. The following steps are aimed at the utilisation of all by-products or waste generated. The kinetic anaerobic digestion of these residues are evaluated in this research to produce biogas/methane. Pepper waste have been employed in batch and semi-continuous anaerobic digestion assays trying the optimization of the yields adding, as catalysts, absorbent nanoparticles and/or using strategies of pretreatment.

In pursuit of carbon neutrality, the demand for metals that are necessary for the development of clean energy technologies is rapidly increasing. Metallurgical waste, such as slag, presents a promising secondary source of these key metals. This research aims to develop an eco-friendly hydrometallurgical process to recover Cu, Ni, and Co from discarded copper/nickel slag. The high-pressure acid leaching (HPAL) was used to selectively leach Ni, Cu, and Co from the fayalite slag, yielding high leaching efficiencies of 99.9%, 89.4%, and 99.9%, respectively, with low Fe and Si tenors to the pregnant leach solution (PLS). The solvent extraction (SX) technique utilizing LIX 984N was used to selectively extract and enrich copper from the dilute PLS to about 23 g/L Cu with a very low Fe concentration of 0.05 g/L. Potassium amyl xanthate (PAX) solution was used to form Ni and Co xanthate complexes from the raffinate solution. Nickel was selectively recovered using ammonia solution, while cobalt xanthate complex was thermally decomposed and recovered as cobalt oxide solids of about 25 wt.% Co. A comprehensive process flowsheet is presented, furthermore, to realize the real application of the developed slag cleaning process, a preliminary economic evaluation was performed.

According to circular economy principles, the recycling and reuse of waste tyre rubber is one of the most advanced and ecological waste disposal technologies. Each year about 19 million tons of tyres are produced, and this amount is increasing each year. One of the most innovative ways to recycle rubber waste is devulcanization. There are many methods of rubber devulcanization, but the most popular are grinding and chemical. In this article devulcanized rubber granules were used for the preparation of rubber samples. Two of them were obtained by the grinding method and one by chemical devulcanization. 15 different rubber samples were produced for the experimental measurements. Multilayer constructions with two solid layers of plasterboard on both sides (GKB and GKFI) and porous acoustic material of rubber sample inside were produced. Measurements were made in an impedance tube and compared with the results of TMM analysis. The same trends of resonant frequencies were determined. According to the results, the resonant frequencies depended on the thickness of the material, since transmission loss values depended on the mass of construction. According to the test results of transmission loss, constructions with 50mm thick rubber samples had on average 3dB better results than the structures with 25mm samples and 5dB better results than structures with 12 mm thick rubber samples. In addition, it was found that higher density plasterboards (GKFI) increased the overall transmission loss value of the structure by 5 dB. The same trends were determined by the TMM method. The test results showed that multi-layered constructions with devulcanized waste rubber had high transmission loss result and could be used for sound insulating structures.

Climate change is one of the main issues that humanity is currently facing due to carbon dioxide emissions caused by the use of fossil fuels. Organic Rankine cycles may play an important role in reducing these emissions since they can be operated by using industrial waste heat of renewable energies. The present study presents a comprehensive bibliographic review of organic Rankine cycles. The study not only actualizes previous reviews that mainly focused on basic cycles operating on subcritical or supercritical conditions but also includes the analysis of novel cycles such as two-stage and hybrid cycles and the used fluids. Recuperative and regenerative cycles are more efficient than reheated and basic single-stage cycles. The use of two-stage cycles makes it possible to achieve higher thermal efficiencies and net power outputs of up to 20% and 44%, respectively, compared with those obtained with single-stage cycles. Theoretical studies show that hybrid systems, including Brayton and organic Rankine cycles, are the most efficient; however, they require very high temperatures to operate. Most organic Rankine cycle plants produce net power outputs from 1 kW up to several tens of kW, mainly using microturbines and plate heat exchangers.

Silicon has a theoretical specific capacity of 4200 mAh g−1, which is considered to have significant potential for anode materials in lithium-ion batteries (LIBs). However, the volume change that occurs in silicon during charging and discharging affects the development of commercial applications. In this work, a yolk-shell structured Si@void@C anode material has been developed to address this problem. The silicon nanoparticle yolk material is obtained by recycling kerf-loss (KL) Si waste from the photovoltaic industry, the carbon shell is prepared via a hydrothermal process with glucose, and the sacrificial interlayer is Al2O3. The synthesized material is used to fabricate anodes that show a high reversible capacity of 836 mAh g−1 at the current density of 0.1 A g−1 after 100 cycles, with a Coulomb efficiency of 71.4%. This work demonstrates a relatively low-cost approach to turn KL Si waste into value-added materials for LIBs.

Despite the development of biorefinery processes, so far this area does not take into account the possibility of coupling the “conventional” composting process with the production of biochemicals. However, net carbon monoxide (CO) production has been observed during bio-waste composting. So far, O2 concentration and temperature have been identified as main variables influencing CO formation. This study aimed to investigate the CO net production during bio-waste composting under controlled laboratory conditions, depending on different aeration rates and temperatures. A series of composting processes were carried out in conditions ranging from ~psychrophilic to thermophilic (T=35, 45, 55, and 65°C) and an aeration rate of 2.7, 3.4, 4.8, and 7.8 L‧h-1. The highest concentrations of CO in each thermal variant was achieved with oxygen deficit (aeration rate 2.7 L‧h-1); additionally, CO levels increased with temperature, reaching ~300 ppm at 65°C. Production of CO in mesophilic and thermophilic conditions draws attention to the biological CO formation by microorganisms capable of producing the CODH enzyme. Further research on the CO production efficiency in these thermal ranges is necessary with the characterization of the microbial community and analysis of the ability of the identified bacteria to produce the CODH enzyme and convert CO from CO2.

The adoption of recycling and proper disposal techniques for electronic waste is crucial in advancing sustainable development. The traditional approaches of motivating people for collection of electronic waste are often insufficient due to inadequate methods reaching out, given incentives, calculating appropriate incentives associate to the task of gathering the electronic waste and a lack of transparency in the entire process. Insufficient collection of electronic waste could result in the release of numerous harmful substances into the environment. Prior research studies have been carried out to tackle the issue of electronic waste management in a broad sense. The findings of those studies indicated diverse strategies, each of which is relevant solely to a restricted range of electronic waste reprocessing circumstances. The current study has presented a proposed technique for incentivizing tasks and activities associated to collection of electronic waste through the adoption of vector space technique. Blockchain smart contact technology, has been used to implemented the strategy. The method used involves various well defined mapping of tasks, nature of activities, and their magnitude in order to derived an incentive. Some scenarios for the calculations of incentives are presented, and the findings reveals the based case is by utilizing weighting scale scheme where each tasks and activities are mapped to its associated inventive rather than providing fixed incentive values. Ethereum was used as digital token for each unit of incentive. This concept has contributed in encouraging personal accountability in the management of e-waste collection in order to cultivate sustainable behaviors for a long term solution.

Red mud (RM) is composed of a waste alkaline solution (pH = 13.3) obtained from the production of alumina. It contains high concentrations of soluble hematite (Fe2O3), goetite (FeOOH), gibisite [Al(OH)3], a boemite (AlOOH), anatase (Tetragonal - TiO2), rutile (Ditetragonal dipyramidal - TiO2), hydrogarnets [Ca3Al2(SiO4)3−x(OH)4x], and perovskite (CaTiO3). It was shown to be an excellent catalytic mixture for biodiesel production. To demonstrate the value of RM, an environmentally friendly process of transesterification in aqueous medium using waste cooking oil (WCO), MeOH and waste alkaline solution (WAS) obtained from aluminum production was proposed. Triglycerides of WCO reacted with MeOH at 60 oC to yield mixtures of fatty acid methyl esters (FAMEs) in the presence of 0.019% (w/w) WAS/WCO using the WAS (0.204 mol L-1, predetermined by potentiometric titration) from aluminum production by the Bayer process. The use of the new catalyst (WAS) resulted in a high yield of the products (greater than 99% yield).