Abstract: The transition to a circular bioeconomy in developing economies is frequently hindered by the operational failure of biogas facilities due to feedstock supply discontinuity. Whilst biochemical potential is traditionally the primary selection criterion, this study postulates that logistic reliability serves as the governing constraint for sustainable implementation. To validate this paradigm shift, a spatially explicit decision-making framework integrating Shannon Entropy and TOPSIS was developed and applied to a representative tropical agro-industrial region. By evaluating conflicting criteria covering logistic availability, technical efficiency, and biochemical stability, the model identified Annual Residue Production as the dominant weighting factor. Results established Cattle Manure as the universal baseload substrate essential for mitigating seasonality risks, outweighing higher-yielding but intermittent agricultural residues. Spatial analysis further revealed distinct bioenergy clusters dictating tailored technological strategies: a high-potential Rice-Livestock cluster suitable for centralised industrial plants overseeing recalcitrant biomass, and a Cassava-Livestock cluster favourable for decentralised, low-tech digestion. This data-driven approach demonstrates that successful substrate selection must transcend theoretical yield maximisation to prioritise supply chain reliability, providing a robust roadmap for de-risking bioenergy investments in tropical regions.

Abstract: Anthropogenic activities represent indirect drivers that generate harmful direct factors, hindering wastewater management (WWM) and causing environmental damage. We analyze this as a process composed of causal relationships where indirect drivers (intangible harmful factors) generate tangible harmful factors. We model this multifactorial process with semantic networks, where the nodes represent intangible or tangible harmful factors, and the interactions between them with causal relationships represented by directed-arcs. We propose an approach that supports decision-making for improving WWM through semantic pathways that describe processes from intangible to tangible harmful factors. A significant advantage of these semantic pathways is their flexibility to modify their structure by adding and removing nodes and arcs, thus allowing for the updating of environmental knowledge. This method facilitates decision-making by providing viable and sustainable solutions to improve WWM performance in coastal tourist municipalities characterized by constant population growth that generates uncontrolled urban sprawl. We applied this approach to the case of the municipality of Acapulco, located on the Mexican Pacific coast. Viable solutions include the restoration of wastewater treatment plants, changes in agricultural practices, mangrove reforestation, and the development of sound urban plans. This methodology can be applied to coastal tourist areas with similar characteristics.

Abstract: Nowadays, biowaste valorization is a key point in circular economy. Digestate and compost are produced from organic waste treatment and can be used as nutrient-rich fertilizers. In Europe, the use of biowaste-derived fertilizers is promoted by the European Fertilizer Regulation (EU) 2019/1009, which requires verification of their biological sta-bility through regulated indices; however, it is not clear whether the proposed indices and threshold values indicate the same level of stability and what correlations there are be-tween them. This study compared four biological stability indices, namely Oxygen Up-take Rate (OUR), Self-Heating (SH), Residual Biogas Potential (RBP), and Dynamic Respirometric Index (DRI), which were tested on 50 samples of compost and digestate. Overall, results revealed that most of the compost and digestate samples were quite far from European standards, according to OUR, SH and DRI indices. On the contrary, the RBP test seemed to be less stringent than the other indices, since a much larger number of samples was closer to or in compliance with the established threshold. Data analysis us-ing Pearson’s coefficients showed a strong linear correlation between the indices. Nev-ertheless, the linear regression predictive model based on experimental data demon-strated that the indices could not represent the same level of stability, providing poor consistency and variability in the predicted values and established threshold. In partic-ular, the DRI test appeared to be more severe than the other aerobic indices. The results obtained suggest revising the biological stability indices and threshold values, depending on the type of matrix.

Abstract: The integration of microalgal cultivation with wastewater streams offers a promising pathway to enhance resource efficiency within circular bioeconomy frameworks. In this study, clarified aquaponics sedimentation effluent was evaluated as a cultivation medium for producing carbohydrate-rich Chlorella sp. biomass targeted for bioethanol feedstock applications. The nutrient composition of the effluent was first characterised, followed by systematic optimisation of wastewater dilution and light intensity under controlled laboratory conditions. Undiluted aquaponics effluent supported robust algal growth without freshwater dilution, achieving a maximum biomass concentration of 2.05 ± 0.03 g L⁻¹ under an optimal light intensity of 185 μmol m⁻² s⁻¹, representing a 78% increase compared with the conventional Bold’s Basal Medium control. Carbohydrate accumulation was significantly enhanced in the wastewater-grown biomass, reaching 40.71 ± 2.14% of dry weight and resulting in a total carbohydrate yield of 0.835 g L⁻¹. Based on stoichiometric conversion, the corresponding theoretical bioethanol potential (0.427 g L⁻¹) was more than three times higher than that of the control. In parallel, the system demonstrated strong bioremediation performance, achieving nitrate and phosphate removal efficiencies of 96.6% and 97.3%, respectively, while maintaining a more stable pH profile than the synthetic medium. These results indicate that clarified aquaponics sedimentation effluent can simultaneously function as an effective growth medium and a wastewater polishing stream.

Abstract: Growth of food online delivery to serve the modern life pattern of customer in urban. Plastic waste increased and had problems with waste management. The aim of this study is to investigate the urban waste composition related to online food delivery in Bangkok metropolitan, food delivery consumption behavior, and plastic waste generated from food delivery. Data from online food delivery customers were collected by online questionnaires from 385 participants. Proportion of plastic waste increased in municipal solid waste. Increase of order food delivery in online platforms about 76.6% of the total participants. The single-use plastic (SUP) generation related to online food delivery in household waste. Participants did not choose the green choices to decline the SUP when ordering food in platforms. These findings suggest reducing SUP from online food delivery, close-loop management requiring cooperation of producer-platform-customer-government. Extended producer responsibility (EPR) should apply for producers to make environmentally friendly products, online food delivery platform increase more incentive for merchants and customers to reduce SUP. Polluter-pay-principle (PPP) might be applied for customers. Government must adopt policy to ban SUP and design system for plastic waste management.

Abstract: Microplastics (MPs) enter terrestrial ecosystems through various pathways, including the use of plastic mulching films, treated sewage sludge, chemical and organic fertilizers. Polypropylene (PP) and polyethylene (PE) are the dominant polymers found in both traditional and facility-based farmland soils. MPs negatively impact soil microbial communities and also harm soil invertebrates such as earthworms, nematodes, and springtails. In plants, MPs can induce oxidative stress, damage cells and inhibit growth. Polystyrene (PS) is often identified as the most hazardous polymer, frequently linked to reduced plant growth, which is the most commonly reported effect of soil MP contamination. This review provides novel insights beyond those reported in previous literature, revealing that greenhouse-based cultivation, vegetable crops, orchards, and vineyards are significant contributors to increased soil microplastic contamination. Furthermore, the findings underscore pronounced global heterogeneity in microplastic concentrations within paddy soils, with recorded levels varying widely from 16 to 10,300 items kg⁻¹. Oxidative stress and additive leaching are the dominant mechanisms driving soil microplastic toxicity across exposed organisms. Quantitative studies of fungal-mediated microplastic biodegradation report mean degradation efficiencies of ~7.5% after 50 days, with mass losses of ~23.8% after 30 days and 35–38% after 90 days.

Abstract: This study was conducted in order to show the transformative potential of extracting into the same solution and using the substances of the component composition of pomegranate peel and their seeds. First, the peel from hand-peeled pomegranates and seeds from juicing their grains in a laboratory press were crushed using a Reitz mill, then mixed taking into account the natural ratio between these parts in three different pomegranate samples [1-1.58/1, 2-1.03/1 and 3-3.77/1 (weight/weight)]. Maceration of these three mixtures was tested with a 1:2 hydromodule (g/ml) for 4.5 hours at 63 °C (mixtures 1 and 2) and for 2.5 hours at 50-55 °C with the addition of 0.15% of the enzyme Fructozym MA-LG by weight of the extraction mixture (mixture 3). Under these conditions, 44.48±0.97 % came out of mixture 1 into solution, 58.04±1.03 % from mixture 2, and 61.16±1.55% of dry substances from their total weight in the initial crude mixture from mixture 3. At the same time, more protein and fiber came out of mixtures 1 and 2 into solutions, but less fat than from mixture 3. Condensed extracts with a dry matter content of 57.0±0.5 g/100 ml were obtained from the primary extracts, including 3.24±0.03 - 4.93±0.04 g/100 ml of polyphenols and 2.80±0.02-4.00±0.04 g/100 ml of fatty oil. The insoluble residues were converted into two dietary powders with a high protein content (from 6.25±0.06 to 8.37±0.09 g/100 g dry weight) and fiber (from 58.98±0.58 to 62.6±0.65g/100 g dry weight).

Abstract: The transition to intelligent, low-carbon mining requires turning solid-waste liabilities into strategic resources. This study develops a Responsible Recovery framework for the disposal and utilisation of mine tailings, integrating global governance standards, advanced process technologies, and emerging AI tools. Using critical-material tailings as a test domain, the framework connects risk classification, disclosure, and flowsheet design to auditable performance metrics. Intelligent modules - from site-inventory parsing and flowsheet recommendation to automated validation of ESG datasets - show how artificial intelligence can improve technical accuracy while strengthening transparency. The approach supports circular recovery of cobalt, nickel, and rare-earth-bearing residues, reducing both waste and import dependence. By aligning digital innovation with established standards such as the Global Industry Standard on Tailings Management (GISTM) and that of the Mining Association of Canada (MAC), the paper shows how tailings management can evolve into a governed, data-driven pathway for recovering critical materials within the wider Intelligent Green Mining agenda.

Abstract: Piggery farming is the largest source of livestock manure in South Korea, generating about 40% of total livestock waste annually. Yet greenhouse gas (GHG) emission data from piggery wastewater treatment systems remain limited, with most studies focused on farm slurry storage rather than process-level emissions. This study quantified methane (CH₄) and nitrous oxide (N₂O) fluxes from a full-scale piggery wastewater treatment facility in, to develop process, season, specific and diurnal specific emission fluxes. Continuous monitoring with a laser-based gas analyzer and customized PVC air-pool chamber was conducted across raw, anaerobic, and aerobic wastewater treatment stages. Mean CH₄ fluxes ranged 1.1-15.6 mg s⁻¹ m⁻², peaking in summer, while N₂O fluxes ranged 0.01-17971 mg s⁻¹ m⁻², with maxima in fall. Aeration tank II and Anaerobic tank I were the dominant emission stages, with night and intra-day peaks. Statistical analysis identified treatment stage and temperature as the main controls on CH₄ variability (p = 0.006 to 0.014), whereas N₂O showed weaker climatic sensitivity. The results provide refined emission factors and emphasize that aeration optimization and denitrification control are key to reducing GHG emissions from livestock wastewater systems in warm, humid regions.

Abstract: This paper presents Greenopoli, an innovative framework for sustainability and waste management education that has engaged over 600 schools and 90,000 students since 2014. Greenopoli is founded on the idea that children and youth can grasp environmental issues as well as adults and act as agents of change within their families and communities. The Greenopoli approach combines scientific accuracy with playful, creative pedagogy to simplify complex topics and stimulate peer-to-peer learning. It includes storytelling, games, field visits, and “green raps” (original environmental songs co-created with students). The framework is adaptive, with content and activities tailored to education stages from kindergarten through university. Educators adopt the role of moderators or facilitators, encouraging students to discuss and discover concepts collaboratively. Greenopoli’s participatory method has been implemented across all age groups, yielding enthusiastic engagement and tangible outcomes in waste sorting and recycling behaviors. The program’s reach has extended beyond schools through collaborations with national recycling consortia, NGOs, municipalities, and media (TV programs, social media, TEDx talks). Numerous awards and recognitions (2017-2025) have highlighted its impact. A comparative analysis shows that Greenopoli’s use of peer-led learning, gamification, and creative communication aligns with global best practices while offering a unique blend of tools. Greenopoli is a novel best-practice model in environmental education, bridging theory and practice and contributing to the goals of Education for Sustainable Development and a circular economy. It demonstrates the effectiveness of engaging youth as change-makers through interactive and creative learning, and it can inspire similar initiatives globally.

Abstract: This study assessed six tomato (Solanum lycopersicum L.) cultivars within an integrated solar-powered closed hydroponic system in Al Dhaid, UAE (25°16′11.2″N, 55°55′52.2″E). The system combined an insect-proof net house, closed hydroponics, root-zone cooling, ultra-low-energy drip irrigation, and a cost-effective solar-powered reverse osmosis (RO) desalination unit to address salinity constraints. The cultivars, selected for their adaptability to controlled environments in the UAE, were evaluated for yield, water-use efficiency (WUE), and fertilizer-use efficiency (FUE). Among them, Torcida recorded the highest mean yield (0.619 kg m⁻² harvest⁻¹), WUE (27.1 kg m⁻³), FUE (26.5 kg fruit kg⁻¹ fertilizer), and marketable fruit ratio (66.3%), followed by Roenza, Eviva, and SV 4129 TH; Lamina was intermediate, while Saley, a bushy type, produced the lowest yield. The top cultivars achieved cumulative yields exceeding 7 kg m⁻²—surpassing regional open-field benchmarks (4–5 kg m⁻²; 3–6 kg m⁻³). Compared with conventional cooled hydroponic greenhouses (3.5 kg plant⁻¹; 8 kg m⁻³), the system demonstrated similar productivity using three times less water. The RO unit produced water at 1.05 US$ m⁻³—58–68% below regional tariffs—while minimizing reliance on grid electricity and mechanical cooling. Overall, the integrated solar-powered hydroponic–RO model proved technically reliable, resource-efficient, and economically viable, offering a scalable solution for sustainable veg-etable production in hyper-arid regions.

Abstract: The packaging sector is undergoing a significant transformation driven by increasing environmental challenges and new European regulatory frameworks. The Packaging and Packaging Waste Regulation (PPWR), following the European Green Deal and Circular Economy Action Plan, introduces five strategic priorities: waste prevention, recyclability, recycled content, compostable materials, and reusable systems. This framework aims to systematically review the current state of academic research in relation to these five intervention areas, assessing the extent to which scientific literature supports the regulation's circular economy objectives. The PPWR sets guidelines for key aspects such as packaging treatment, recycling targets, Extended Producer Responsibility (EPR) and material optimization. These aspects are strongly linked to market dynamics, driving innovation and new developments of packaging design. This study aims to provide a comprehensive overview of the industry’s evolution, with a focus on the crucial role of the circular economy in addressing the persistent issue of packaging waste. By conducting a systematic literature review using the PSALSAR method, the research explores the relationship between the regulation’s structural design and the European Commission’s Priority areas. The results reveal that Waste Prevention and Reusability are the most researched areas, particularly concerning environmental assessments and regulatory tools like EPR. Additionally, while Recyclability has been studied from technical and environmental perspectives, there is still a lack of research on how it connects with supply chain and material market trends. Strengthening these connections could significantly enhance recycling efficiency and improve the sustainability of packaging system. Furthermore, financial incentives and policy strategies could play a key role in facilitating the transition to a circular economy. Addressing these gaps will foster a more integrated understanding of sustainable packaging solutions.

Abstract: In sub-Saharan Africa, land degradation and climate change threaten food security by reducing soil productivity and water availability. Soil and water conservation (SWC) technologies can restore soil health, enhance moisture retention, and support crop growth under adverse conditions. This review identifies SWC technologies applied in climatically similar African regions with the aim of informing adoption in Senegal, particularly in Sédhiou and Tambacounda regions. Using K-means clustering on 19 WorldClim bioclimatic variables, 35 comparable countries were identified, of which 17 met inclusion criteria based on data availability and ≥60% climatic similarity. Around 85 technologies were reviewed, including water harvesting, soil-moisture conservation, and erosion control, assessed for their compatibility across rainfall patterns, and land gradients and uses. The review highlights 12 successful technologies across Africa with high potential for cross-border transfer and upscaling in Senegal’s agroecological context. While countries such as Burkina Faso, Kenya, and Malawi lead in technology adoption and diversity, Senegal lags behind due to institutional gaps, limited funding, and weak extension systems. The findings highlight the importance of site-specific water management for improving soil conservation, biodiversity protection, climate adaptation, and food security, and emphasize the need for policy integration, stakeholder empowerment, private-sector engagement, and cross-border learning to accelerate adoption.

Abstract: Efficient water recycling is imperative for the sustainable presence of humans during long-duration and deep-space missions, where resupply from Earth is not a viable option. This study proposes a kombucha-based photobioreactor (Kombucha-PBR) as a novel biological approach for the treatment of wastewater generated in space habitats. Kombucha, a symbiotic microbial consortium of bacteria and yeasts, produces bacterial cellulose and demonstrates high stability and resistance to contamination, making it suitable for closed-loop bioprocessing in microgravity conditions. The reactor was evaluated using synthetic wastewater formulated by NASA, which was representative of spacecraft effluents. Treatment performance was assessed through the removal of chemical oxygen demand (COD) and total nitrogen (TN). Following an initial adaptation phase, the system demonstrated stable performance, with a decrease in ammonia concentrations from 200 mg·L⁻¹ to 44 mg·L⁻¹ (>80% removal efficiency) and an average COD removal of 81% after 30 days. The fixed-bed configuration provided an extensive surface area for the growth of biofilm, thereby enabling simultaneous carbon and nitrogen removal whilst minimising energy requirements and operational complexity. The findings demonstrate that the Kombucha-PBR offers a compact, low-energy, and microgravity-compatible solution for regenerative water recovery. Its integration into spacecraft life support systems has the potential to significantly advance sustainable resource management and autonomy for future long-term space missions.

Abstract: The spatial configuration of Waste-to-Energy (WtE) infrastructure plays a decisive role in determining the environmental and economic performance of municipal solid waste (MSW) management systems. This study applies a Life Cycle Assessment (LCA) methodology to evaluate the environmental implications of centralized and decentralized siting strategies for Refuse-Derived Fuel (RDF) utilization in Greece. Two alternative scenarios were modeled: (i) a centralized approach based on six large WtE plants as proposed by the Greek Ministry of Environment and Energy (gr. YPEN), and (ii) a decentralized approach involving smaller, regionally distributed units located closer to Recycling and Recovery Facilities (RRFs). Using the SimaPro software and the CML/ReCiPe 2016 methodologies, environmental impacts were quantified across categories including global warming potential, acidification, eutrophication, and particulate matter formation. The results indicate that the decentralized scenario yields substantial environmental advantages, with reductions ranging from 33% to 45% across all impact categories and a 35% decrease in CO₂-equivalent (CO2e) emissions compared to the centralized scenario. Economic analysis confirms these findings, showing a 31% reduction in total transport and emissions-related costs due primarily to minimized long-distance and maritime transport. The study concludes that decentralized RDF-to-energy systems offer a more balanced and sustainable pathway, enhancing operational flexibility, lowering environmental burdens, and improving social acceptance. These results underscore the importance of integrating spatial and logistical parameters in national WtE planning to align with EU waste hierarchy principles and circular economy objectives.

Abstract: Samples of flotation tailings generated during the exploitation and processing of Zn–Pb–Cu–Ag ore from the Rudnik mine (Serbia) were investigated for their mineralogical, geo-chemical, and magnetic susceptibility properties. The flotation tailings consist of a com-plex mineral assemblage, including silicates, carbonates, sulfides, phosphates, sulfates, oxides, hydroxides, and native elements. Quartz and calcite dominate the coarse fraction (>500 µm), accompanied by epidote, andradite, and diopside. Sulfide minerals are con-centrated in finer fractions (400 µm), with pyrite and arsenopyrite being the most abun-dant, followed by pyrrhotite, sphalerite, galena, and chalcopyrite. These sulfides form in-tricate intergrowths or occur as dispersed grains within a silicate–carbonate matrix. Post-depositional oxidative alteration is moderately developed, with pyrite being replaced by hematite, galena by cerussite, and chalcopyrite by malachite. Geochemical analyses reveal that SiO₂ (avg. 38.98 wt%), Fe₂O₃ (avg. 23.68 wt%), and Al₂O₃ (avg. 8.95 wt%) domi-nate the composition. Economically significant metals include Zn (avg. 0.47 wt%), Pb (avg. 0.20 wt%), Cu (avg. 0.11 wt%), Ag (max. 19 µg/g), and Bi (max. 130 µg/g). Mass mag-netic susceptibility shows a significant correlation with S (r = 0.92), Co (r = 0.90), and Bi (r = 0.87); moderate correlation with Fe₂O₃, Al₂O₃, and As; and negative correlation with Mn, TiO₂, Zn, and Pb. The ferromagnetic phase (sensu lato) most likely originates from hematite formed during pyrite alteration, as well as from pyrrhotite and goethite.

Abstract: The global demand for compost, produced through the bioconversion of organic waste into nutrient-rich soil amendments, is increasing due to the adverse environmental, health, and economic impacts of synthetic fertilizers. Compost use offers a cost-effective and sustainable alternative, improving soil fertility and long-term productivity. However, the potential of tobacco waste as a composting substrate remains insufficiently investigated. This study aimed to evaluate the feasibility of utilizing tobacco waste as a composting feedstock and to develop an optimized composting method. Tobacco waste (scrap leaves and midrib stems) was composted with cow manure in earthen pots to promote decomposition and nutrient mineralization, and its performance was compared with compost produced from cow manure and vegetable waste (vegetable leaves). Vermicomposting, which involves the addition of earthworms to conventional compost treatments, was also implemented to enhance composting efficiency and nutrient release. The final composts, both conventional and vermicompost, were analyzed for organic carbon (OC), nitrogen (N), phosphorus (P), potassium (K), sulfur (S), and the maturity duration. Among the three conventional compost variants, the mixture of cow manure and vegetable waste exhibited a notable nutrient composition, with the highest organic carbon (15.3%) and phosphorus (0.42%) contents. All three vermicompost variants outperformed their conventional counterparts in terms of nutrient concentrations and achieved maturity in shorter durations. The vermicompost, comprising cow manure, vegetable leaves, and earthworms, recorded the highest levels of organic carbon (45.3%) and nitrogen (2.50%), reaching maturity within 40 days. The cow manure with tobacco stem mixed vermicompost was notable for its elevated potassium (1.35%) and sulfur (0.89%) contents. The results indicate that vermicomposting offers a faster and more nutrient-enriched composting approach, particularly with vegetable residues. Incorporating tobacco waste into this process has the potential to produce high-quality compost, presenting a sustainable strategy for waste valorization and enhancing soil fertility.

Abstract: Hydroxamic acid extractors (such as LIX984) show high extraction efficiency in extracting nickel from electron-free nickel waste solution, but there is a problem with a slow extraction rate. This study investigated the effect of adding specific amounts (2-5 vol.%) of three organophosphate extractants (P507, P204, and Cyanex272) to LIX984, and the results showed that adding 2-5 vol.% P507 or Cyanex272 can significantly increase extraction efficiency and kinetic properties. When 2-5 vol% organophosphorus extractant was added, the extraction rate increased 1.5-10 times， indicating a direct correlation between the content of organophosphorus extractant and the acceleration of the extraction process, with an increase in content corresponding to an increase in extraction rate. Compared to the case when additives were not used, nickel extraction efficiency reached more than 99% when 5 vol% P507 was added. while in the absence of additives was only 46%; at the same time, the rate of extraction was also significantly improved. With 2 vol% P204, the removal efficiency reached 99.8%. When applied to a waste solution for non-electroplating (pH 4-6), the first addition of 2-5 Vol.% P204 or P507 for selective removal of iron and zinc impurities and then pH up to 6-7 with a mixture of organophosphate extracts, and the spent electroless nickel plating baths are extracted with LIX984 extractant mixed with organic phosphoric acid extractant to obtain the nickel salt solution with higher purity by stripping. Therefore, in the spent electroless nickel plating baths with recovered nickel, the organic phosphoric acid extractants P507, P204, and Cyanex272 can be used as a good promoter of the hydroxamic acid extractant LIX984, and the new extractant obtained can achieve both a better nickel extraction effect and a higher nickel extraction rate.

Abstract:

The construction industry increasingly seeks sustainable solutions to reduce environmental impact and energy consumption. This study explores the innovative use of industrial sludge generated from the wastewater treatment of detergent manufacturing as a partial substitute for Portland cement in mortar production. The sludge, characterized by high SiO₂ (46.58%) and CaO (28.66%) content, was incorporated at substitution rates of 0% to 30%. Mortars were prepared and tested according to NF EN 196-1 standards for mechanical strength, and thermophysical properties were assessed using the Hot Disk TPS 1500 system. Results demonstrate that up to 20% sludge replacement maintains acceptable mechanical performance (compressive strength: 12.63 MPa at 28 days vs. 13.91 MPa for control; flexural strength: 3.93 MPa vs. 4.65 MPa) while significantly enhancing thermal insulation. Thermal conductivity decreased from 1.054 W/m·K (0% sludge) to 0.797 W/m·K (20% sludge), and thermal diffusivity dropped from 0.6096 mm²/s to 0.504 mm²/s. XRD analysis revealed the formation of new phases, such as gismondine, indicating beneficial pozzolanic activity. These findings highlight the dual benefit of valorizing detergent sludge and improving building energy efficiency, offering an eco-efficient alternative to traditional mortars aligned with circular economy and low-carbon construction goals.

Abstract: The application of efficient optical-electrical sorting technology for the automatic separation of copper mine waste rocks not only enables the recovery of valuable copper metals and promotes the resource utilization of non-ferrous mine waste, but also conserves large areas of land otherwise used for waste disposal and alleviates associated environmental issues. However, the process is challenged by the low copper content and fine dissemination of copper-bearing minerals, including copper metallic elements, and the subdued irradiation response of sulfur. To address these challenges, this study leverages dual-energy X-ray imaging and multi-modal learning, proposing a lightweight twin-tower convolutional neural network (CNN) designed to fuse high- and low-energy spectral information for the automated sorting of copper mine waste rocks. Additionally, the study integrates an emerging Kolmogorov-Arnold network as a classifier to enhance the sorting performance. To validate the efficacy of our approach, a dataset comprising 31,057 pairs of copper mine waste rock images with corresponding high and low-energy spectra was meticulously compiled. The experimental results demonstrate that the proposed lightweight method achieves competitive, if not superior, performance compared to contemporary mainstream deep learning networks, yet it requires merely 1.32 million parameters (only 6.2% of ResNet-34), thereby indicating extensive potential for practical deployment.