ARTICLE | doi:10.20944/preprints202108.0092.v1
Subject: Biology, Anatomy & Morphology Keywords: petroleum; metagenomics; core microbiota, functional potential, oil fields
Online: 3 August 2021 (15:29:57 CEST)
Microorganisms inhabiting subsurface petroleum reservoirs are key players in biochemical transformations. The interactions of microbial communities in these environments are highly complex and still poorly understood. This work aimed to assess publicly available metagenomes from oil reservoirs and implement a robust pipeline of genome-resolved metagenomics to deci-pher metabolic and taxonomic profiles of petroleum reservoirs worldwide. Analysis of 301,2 Gb of metagenomic information derived from heavily flooded petroleum reservoirs in China and Alaska to non-flooded petroleum reservoirs in Brazil enabled us to reconstruct 148 MAGs of high and medium quality. At the phylum level, 74% of MAGs belonged to bacteria and 26% to ar-chaea. The profiles of these MAGs were related to the physicochemical parameters and recovery management applied. The analysis of the potential functional core in the reservoirs showed that the microbiota was specialized for each site, with 31.7% of the total KEGG orthologies annotated as functions (1,690 genes) common to all oil fields, while 18% of the functions were site-specific, i.e., present only in one of the oil fields. The oil reservoirs with lower level of intervention were the most similar to the potential functional core, while the oil fields with longer history of water in-jection had greater variation in functional profile. These results show how key microorganisms and their functions respond to the distinct physicochemical parameters and interventions of the oil field operations such as water injection and expand the knowledge of biogeochemical trans-formations in these ecosystems.
REVIEW | doi:10.20944/preprints202108.0124.v1
Subject: Biology, Anatomy & Morphology Keywords: rhizoremediation; plant growth promoting rhizobacteria; petroleum hydrocarbon-degrading bacteria; salix; contaminated soils; alkanes; polycyclic aromatic hydrocarbons
Online: 4 August 2021 (22:30:31 CEST)
Soil contamination with petroleum hydrocarbons (PHCs) has become a global concern in the word due to intensification of industrial activities. This creates a serious environmental issue, therefore there is a need to find solutions, including application of efficient remediation technologies, or to improve current techniques. Rhizoremediation is a sub-category of the phytoremediation which refers to Phytomanagement that uses plants and their associated microbiota. These green technologies have received a global attention as a cost-effective and possible efficient remediation technique that can be applied to cleanup PHCs-polluted soils. The mechanism of rhizoremediation process is that plant roots stimulate soil microbes to mineralize organic contaminants to H2O and CO2. However, this multipartite interaction is much complex because many biotic and abiotic factors can influence microbial processes in the soil, making the efficiency of rhizoremediation unpredictable. This review reports the progress made on rhizoremediation approaches that can overcome the limitations and improve the efficiency of PHCs-contaminated soils. The addressed approaches in this review include: 1) selecting plants with desired characteristics suitable for rhizoremediation, 2) the exploitation and manipulation of plant microbiome by using inoculant containing plant growth-promoting rhizobacteria (PGPR) or hydrocarbon-degrading microbes, or a combination of both types of organisms, and 3) enhancement of the understanding of how host-plant assembles a beneficial microbiome, and how it functions, under pollutant stress.
ARTICLE | doi:10.20944/preprints201609.0075.v1
Online: 22 September 2016 (10:27:48 CEST)
Diesel, gas oil, whole crudes, and bitumen samples were subjected to sulfoxidation, and then subjected to hydroxide attack in the presence of ethylene or propylene glycol. The resultant oils were analyzed by XRF for total sulfur and XANES spectroscopy for sulfur speciation at each stage. The combination of these analyses gave the total amount of sulfur as organic sulfide, sulfoxide, and sulfone at each stage of treatment so as to determine the effectiveness of the desulfonylation for sulfur compounds of different oxidation states.
ARTICLE | doi:10.20944/preprints202209.0446.v1
Subject: Social Sciences, Organizational Economics & Management Keywords: petroleum; oil market; oil; statistics
Online: 28 September 2022 (15:35:31 CEST)
The energy matrix worldwide has been going through difficulties in its discussions - such as irregular exploration, inefficient public policies, and arbitrariness concerning diplomatic and political definitions of those involved in this market. This work's general objective consists in analyzing associations and statistical inferences of the largest world oil producers, assimilating the contributions and singularities of this market from 1993 to 2020. Based on the Organization of the Petroleum Exporting Countries (OPEC), it was possible to identify the possible inferences and contributions of the ten largest oil producers in the world in more than two decades using statistical analysis through correlation, regression, and statistical analysis of variables. According to the research and the literature on the area, the oil market proposes support to its discussions, mainly in its productive approaches. It is possible to identify this market as a solid link to geopolitical actions, distributing the possibilities through economic bias and socio-cultural and historical factors on a global level.
ARTICLE | doi:10.20944/preprints201801.0009.v1
Subject: Biology, Animal Sciences & Zoology Keywords: polycyclic aromatic hydrocarbons; petroleum; Clarias gariepinus
Online: 2 January 2018 (09:56:53 CET)
One hundred and twenty (120) fingerlings of Clarias gariepinus (mean weight: 0.96 ± 0.1g) were randomly exposed to 4 experimental treatments of petroleum, based on LC50 values (6.4mg/L of crude oil, 8.7mg/L of petrol, 8.0mg/L of kerosene and 7.8mg/L of diesel oil) and replicated thrice, to determine polycyclic aromatic hydrocarbons (PAH) in exposed fish for 96 h. There was no significant difference (P > 0.05) in total (PAHs) between crude oil (97.1 ng/uL) and diesel (97.2 ng/uL) exposed fish and also between petrol (53.2 ng/uL) and kerosene (49.6 ng/uL) exposed fish, but there was a significant difference (P < 0.05) in PAH levels of the crude oil/diesel exposed -groups of fish compared to petrol/kerosene exposed -groups of fish (97.1/97.2 and 53.2/49.6 ng/uL). Naphthalene correlated positively to benzo a anthracene (r=0.672, (P < 0.05), benzo b fluoranthene (r=0.681, P < 0.05) and chrysene (r=0.615, P < 0.05) but did not correlate to fluorene. Benzo a anthracene correlated positively to benzo a pyrene (r=0.578, P < 0.05), phenathrene (r=0.685, P < 0.05) but did not correlate to acenaphthene. Fluorene correlated positively to benzo a pyrene (r=0.695, P < 0.05) but did not correlate to chrysene. Chrysene correlated positively to dibenzo a,h, pyrene (r=0.658, P < 0.05) to phenathrene and benzo b fluoranthene (r=0.659, P< 0.05). Indeno 123 cd- pyrene and fluranthene however did not correlate to other PAHs except naphthanene, acenaphthene and acenaphthylene. The level of PAH in fish may translate to the toxicity effect since crude oil and diesel with lower LC50 (6.4 and 7.8 mg/L) deposited greater PAH than kerosene and petrol with higher LC50 (8.7 and 8.0 mg/L) in fingerlings of C. gariepinus. High risk to cancer disorders may occur in exposed fish to petroleum with high incidence of fluorene , anthracene, pyrene and benz a anthracene which correlated positively to benzo a pyrene which provide some basis for predicting impact of oil spills on fingerling population.
REVIEW | doi:10.20944/preprints201811.0166.v1
Subject: Life Sciences, Biotechnology Keywords: Biodegradation, thermophiles, petroleum hydrocarbons, aliphatics, aromatics, metabolites
Online: 7 November 2018 (14:34:42 CET)
Contamination of the environment by petroleum products is a growing concern worldwide, and strategies to remove these contaminants have been evaluated. One of these strategies is biodegradation, which consists of the use of microorganisms. Biodegradation is significantly improved by increasing the temperature of the milieu, thus, the use of thermophiles, microbes that thrive in high-temperature environments, will render this process more efficient. For instance, various thermophilic enzymes have been used in industrial biotechnology because of their unique catalytic properties. Biodegradation has been extensively studied in the context of mesophilic microbes, and the mechanisms of biodegradation of aliphatic and aromatic petroleum hydrocarbons have been elucidated. However, in comparison, little work has been carried out on the biodegradation of petroleum hydrocarbons by thermophiles. In this paper, a detailed review of the degradation of petroleum hydrocarbons (both aliphatic and aromatic) by thermophiles has been carried out. This work has identified the characteristics of thermophiles, and unravelled specific catabolic pathways of petroleum products that are only found in thermophiles. Gaps that limit our understanding of the activity of these microbes have also been highlighted, and finally, different strategies that can be used to improve the efficiency of degradation of petroleum hydrocarbons by thermophiles have been proposed.
COMMUNICATION | doi:10.20944/preprints201806.0053.v1
Subject: Engineering, Other Keywords: petroleum sludge; cement clinker; free lime content; burnability
Online: 5 June 2018 (08:32:29 CEST)
The objective of this study is to investigate the performance of incorporating petroleum sludge waste as raw materials into the cement clinker production. The burnability and the structural analysis of the produced clinker were studied. The results showed that the addition of petroleum sludge into the clinker matrices improved the burnability of the clinker by lowering the free lime content. Moreover, 2.5% and 5% of this waste was effective and did not affect the quality of the cement clinker negatively. This study, which is the first to investigate the incorporation of petroleum sludge into cement production, provides also a complete elimination of this waste from the environment.
ARTICLE | doi:10.20944/preprints201708.0033.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: petroleum sludge; characterization; total organic carbon; metal concentration
Online: 8 August 2017 (13:24:39 CEST)
Thermal plasma technique is becoming prominent in the treatment of variety of waste ranging from municipal solid waste, incinerator residue, hospital waste, electronics waste and industrial sludge. Application of the new treatment technology to petroleum sludge requires information on the nature and characteristics of the sludge that will be use to optimize the treatment system. In this investigation, petroleum sludge obtained from Petronas Melaka was characterized for its physical and chemical features. Proximate and ultimate analysis as well as determination of elemental composition were carried out. The sludge was found to contain high moisture (78.91%), low ash (5.06%), low volatiles (5.52%) and high fixed carbon (10.51%). The sludge has a TOC of 54.48% and HHV of 23.599MJ/kg. Despite the high moisture content, the higher heating value (HHV) is high when compared to literature values. The high value of HHV may be associated with the high fixed carbon, low ash content and high value of TOC. The apparent density of the sludge is slightly lower. Fourteen heavy metals are detected in significant quantities. Proper waste management that will safely dispose the sludge is required. The waste disposal technique should take into cognizant the possibility of leaching of heavy metals into ground water on one hand and the gasification of lighter ones on the other.
ARTICLE | doi:10.20944/preprints201608.0099.v1
Subject: Materials Science, Polymers & Plastics Keywords: PET; Petroleum Coke; Mechanical Alloying; Thermal studies; XRD
Online: 9 August 2016 (14:22:43 CEST)
The thermal degradation behaviour of 10:90 and 90:10 blends of Polyethylene Terephthalate (PET) and petroleum coke has been investigated using mechanical alloying (milling) at 300 rpm and for periods up to 1-10 hours. Milled specimens were characterised using SEM and x-ray diffraction; their thermal degradation behaviour was investigated using thermo-gravimetric analyser (TGA) for temperatures up to 1200°C. Whereas PET specimens showed a tendency towards flattening out and increased surface area during collisions in ball mills, petroleum coke particles tended to break down into smaller particles. 10:90 and 90:10 blends of PET and coke showed significant microstructural evolution with increasing speeds and time including fracture, strain hardening and re-welding. X-ray diffraction results showed clear evidence for increasing amorphous component in petroleum coke without much influence on PET crystallinity. Thermo-gravimetric results showed a significant increase in the overall degradation and much higher weight losses associated with mechanical alloying. This study has shown that mechanical alloying could be used to modify the degradation behaviour of coke/plastic blends and corresponding yield during pyrolysis with implications for plastic waste management.
ARTICLE | doi:10.20944/preprints201806.0500.v1
Subject: Materials Science, Nanotechnology Keywords: nanocellulose; retention; petroleum; energy; oil; petrochemical; cellulose nanocrystals; nanoparticle
Online: 30 June 2018 (15:15:54 CEST)
The application of nanotechnology to the petroleum industry has sparked recent interest to increase oil recovery while reducing environmental impact. Nanocellulose is an emerging nanoparticle that is derived from trees and may provide an environmentally friendly alternative to current enhanced oil recovery (EOR) technologies. However, before nanocellulose can be applied as an EOR technique, further understanding of its transport behavior and retention in porous media is required. The research documented in this paper examines retention mechanisms that occur during nanocellulose transport. In a series of experiments, nanocellulose particles dispersed in brine were injected into sandpacks and Berea sandstone cores. The resulting retention and permeability reduction were measured. The experimental parameters that were varied include sand grain size, nanocellulose type, salinity, and flow rate. Under low salinity conditions, the dominant retention mechanism was adsorption and when salinity was increased, the dominant retention mechanism shifted towards log-jamming. Retention and permeability reduction increased as grain size decreased, which results from increased straining of nanocellulose aggregates. In addition, each type of nanocellulose was found to have significantly different transport properties. The experiments with Berea sandstone cores indicate that some pore volume was inaccessible to the nanocellulose. As a general trend, the larger the size of aggregates in bulk solution, the greater the observed retention and permeability reduction. Salinity was found to be the most important parameter affecting transport. Increased salinity caused additional aggregation, which led to increased straining and filter cake formation. Higher flow rates were found to reduce retention and permeability reduction. Increased velocity was accompanied by an increase in shear which is believed to promote breakdown of nanocellulose aggregates.
REVIEW | doi:10.20944/preprints202009.0670.v1
Subject: Earth Sciences, Atmospheric Science Keywords: petroleum refining carbon footprints; refining carbon footprints; refined product carbon footprints
Online: 27 September 2020 (08:32:10 CEST)
Energy-related greenhouse gas emissions dominate the carbon footprints of most product systems, and petroleum is one of the main types of energy sources. This is consumed as a variety of refined products – most notably diesel, petrol (gasoline) and jet fuel (kerosene). Refined product carbon footprints are of great importance to regulators, policymakers and environmental decision-makers. For instance, they are at the heart of legislation such as the European Union’s Renewable Energy Directive or the United States’ Renewable Fuels Standard. This study identified 14 datasets that report footprints for the same system, European petroleum refining. For the main refined products – diesel, petrol and jet fuel – footprints vary by at least a factor of three. For minor products, the variation is even greater. Five different organs of the European Commission have estimated refining footprints: for main products these are relatively harmonic; for minor products much less so. The footprint variation is due mainly to differing approaches to refinery modelling, especially regarding the rationale and methods applied to assign shares of the total burden from the petroleum refinery operation to the individual products. Given the economic/social importance of refined products, a better harmony of their footprints would be valuable to their users.
ARTICLE | doi:10.20944/preprints201810.0044.v1
Subject: Keywords: environmental impact assessment, remediation, petroleum-contaminated sites, environment, health, capacity building
Online: 3 October 2018 (12:01:44 CEST)
Human-generated, natural occurrences and other actions connected with the petroleum industry have contributed expansively to the contamination of numerous areas of human habitant, thus effecting overwhelming challenges and constraints to sustainable human health, development and the biosphere. The sites commonly associated include derelict pits, hydrocarbon onshore release sites, and places to where oil slicks exuding from offshore releases are blown onshore. In diverse cases, remediation is pertinent to restore the affected ambient. This is required despite the complexity and intricate pore structure and fluid trafficking trajectories of soil which are not easily amenable to remediation. Due to the complex assemblage of contaminated soil, it is necessary to conduct an encompassing site assessment by considering the potential impact of the environment and human health prior to proper selecting and implementing of a desirable remediation process. There are extant remediation methodologies which are effective and efficient for the clean up of contaminated shorelines and other petroleum-contaminated sites involving inter alia agricultural activities. There are salient variations in the techniques to expunge contaminants regarding spatiotemporal and pecuniary costs or considerations due to the gross environmental hazards entailed. This study provides for the opportunity to harness and sustain the capacity for the mitigation of untoward impacts, and induce the latitude for an enabling condition in sustainable human health, environment and development in the petroleum industry and other anthropogenic activities.
ARTICLE | doi:10.20944/preprints202212.0489.v1
Subject: Social Sciences, Law Keywords: Petroleum Resources; Contract Structure; Production Sharing Agreement; International Oil Company; National Oil Company
Online: 26 December 2022 (12:03:54 CET)
Most developing countries with petroleum resources are constrained in the ability to refine their oil and gas resources. This virtually results in the involvement of the International Oil Company (IOC) by the National Oil Company (NOC) of a particular nation to enter into an agreement to achieve the production of oil based on an agreed framework. However, in cur-rent development, there is little focus on the contractual agreement, particularly on the pro-duction sharing agreement by the IOC in the exploration of petroleum resources of developing countries. The primary objective of this paper is to critically explore the contract structure of production sharing agreement by the IOC in the exploration and development of petroleum resources in developing countries. Content analysis was used as the methodology of the study after examining several literatures. The findings indicate that the contract structure of the production sharing agreement (PSA) between NOC and IOC plays a significant role in the cost and risk of exploration and development of oil. In addition, it is noted that the joint committee of the NOC and IOC plays a paramount role in monitoring the operations of PSA between the NOC and IOC. Hence, from the gross oil production, the NOC gets its share as profit while IOC gets its share income tax. As an instrument of contract structure in the oil and gas sector, PSA needs further entrenchment between IOC and NOC to avoid likely issues that can emanate between the two parties in the face of current developments.
REVIEW | doi:10.20944/preprints202203.0011.v2
Subject: Chemistry, Chemical Engineering Keywords: colloids; interface; formulation; surfactant; cosmetics; petroleum; food; paint; pharmaceutics; emulsions; foams; dispersions; HLDN
Online: 2 March 2022 (07:30:26 CET)
Formulation is an ancient concept, although the word has been used only recently. The first formulations made our civilization advance by inventing bronze, steel, and gunpowder; then, it was used in medieval alchemy. When chemistry became a science and with the golden age of organic synthesis, the second formulation period began. This made it possible to create new chemical species and new combinations “à la carte.” However, the research and developments were still carried out by trial and error. Finally, the third period of formulation history began after World War II, when the properties of a system were associated with its ingredients and the way they were assembled or combined. Therefore, the formulation and the systems’ phenomenology were related to the generation of some synergy to obtain a commercial product. Winsor’s formulation studies in the 1950s were enlightening for academy and industries that were studying empirically surfactant-oil-water (SOW) systems. One of its key characteristics was how the interfacial interaction of the adsorbed surfactant with oil and water phases could be equal by varying the physicochemical formulation of the system. Then, Hansen’s solubility parameter in the 1960s helped to reach a further understanding of the affinity of some substances to make them suitable to oil and water phases. In the 1970s, researchers such as Shinoda and Kunieda, and different groups working in Enhanced Oil Recovery (EOR), among them Schechter and Wade’s group at the University of Texas, made formulation become a science by using semiquantitative correlations to attain specific characteristics in a system (e.g., low oil-water interfacial tension, formulation of a stable O/W or W/O emulsion, or high-performance solubilization in a bicontinuous microemulsion system at the so-called optimum formulation). Nowadays, over 40 years of studies with the hydrophilic-lipophilic deviation equation (HLD) have made it feasible for formulators to improve products in many different applications using surfactants to attain a target system using HLD in its original or its normalized form, i.e., HLDN. Thus, it can be said that there is still current progress being made towards an interdisciplinary applied science with numerical guidelines. In the present work, the state-of-the-art of formulation in multiphase systems containing two immiscible phases like oil and water, and therefore systems with heterogeneous or micro-heterogeneous interfaces, is discussed. Surfactants, from simple to complex or polymeric, are generally present in such systems to solve a wide variety of problems in many areas. Some significant cases are presented here as examples dealing with petroleum, foods, pharmaceutics, cosmetics, detergency, and other products occurring as dispersions, emulsions, or foams, that we find in our everyday lives.
ARTICLE | doi:10.20944/preprints202107.0344.v1
Subject: Biology, Anatomy & Morphology Keywords: Phytoremediation; Petroleum hydrocarbon-degrading bacteria; Salix; Eleocharis; Alkanes; Polycyclic aromatic hydrocarbons; Plant growth promoting rhizobacteria
Online: 15 July 2021 (09:27:25 CEST)
Phytoremediation, a method of phytomanagement using the plant holobiont to clean up polluted soils, is particularly effective for degrading organic pollutants, such as alkanes and polycyclic aromatic hydrocarbons (PAHS). However, the respective contributions of host plants and their associated microbiota within the holobiont to the efficiency of phytoremediation is poorly understood. Identification of plant-associated bacteria capable of efficiently utilizing these compounds as carbon source while stimulating plant-growth, is a keystone for phytomanagement engineering in order to improve the efficiency of pollutant removal. In this study, we sampled the rhizosphere and the surrounding bulk soil of Salix purpurea and Eleocharis obusta from the site of a former petrochemical plant in Varennes, QC, Canada. Our objectives were to: (i) isolate and identify indigenous bacteria inhabiting these biotopes; (ii) assess the ability of isolated bacteria to utilize alkanes (dodecane and hexadecane) and PAHs (naphthalene, phenanthrene and pyrene) as the sole carbon source, and (iii) determine the plant growth-promoting (PGP) potential of the isolates using five key traits. A total of 438 morphologically different bacterial isolates were obtained, purified, preserved and identified through PCR and 16S rRNA gene sequencing. Identified isolates represent 62 genera, including taxa such as Acinetobacter, Arthrobacter, Bacillus, Enterobacter, Nocardia, Pseudomonas, Rhodococcus, Streptomyces and Variovorax. Approximately, 32% of bacterial isolates, including Arthrobacter, Pseudomonas, Streptomyces, Enterobacter, Nocardia, Acinetobacter and Microbacterium, were able to utilize all five different hydrocarbons compounds. Additionally, 5% of tested isolates belonging to genera Pseudomonas, Acinetobacter, Serratia, Klebsiella, Microbacterium, Bacillus and Stenotrophomonas possessed all five of the tested PGP functional traits. This culture collection of diverse, petroleum-hydrocarbon degrading bacteria, with multiple PGP traits, represents a valuable resource for future use in environmental bio- and phyto-technology applications, including phytoremediation of petroleum hydrocarbons contaminated soils and phytomanagement of anthropized areas.
ARTICLE | doi:10.20944/preprints201812.0043.v1
Subject: Mathematics & Computer Science, Probability And Statistics Keywords: volatility; returns; stocks; total petroleum; akaike information criterion (AIC), GARCH; value-at-risk (VaR), backtesting
Online: 4 December 2018 (03:16:48 CET)
Total Nigeria Plc is a Marketing and Services subsidiary of Total; a multinational energy company operating in more than 130 countries and committed to providing sustainable products and services for its customers. For over 50 years, Total Nigeria Plc has remained the leader in the downstream sector of the Nigerian oil and gas industry. This study investigated the volatility of the stock price of Total Petroleum Nigeria plc using nine (9) GARCH models namely sGARCH, gjrGARCH, eGARCH, iGARCH, aPARCH, TGARCH, NGARCH, NAGARCH and AVGARCH. We also investigated the Value-at-Risk (VaR) and Backtesting of the Models. The aim actually of this study is to boost the confidence of the shareholders and investors of the Total Nigeria plc. To achieve this, daily stock price for Total petroleum Nigeria plc from secondary was collected from January 2nd 2001 to May 8th 2017. . The study used both normal and student t innovations, using Akaike Information Criterion (AIC) to select the best model, for normal innovations for log returns and cleansed log returns of Total plc, the eGARCH and sGARCH models performed best respectively, while NGARCH model performed best for student t innovation for both log returns and cleansed returns of Total plc. The persistence of the models are stable except in few cases where iGARCH, eGARCH where not stable. Also for student t innovation, the sGARCH and gjrGARCH fails to converge. The mean-reverting number of day for the returns of Total Nigeria plc differs from model to model. Evidence from the VaR Analysis revealed from the selected models revealed that the Risk of VaR losses is high at 99% confidence level, slightly high at 95% confidence level and better at 90% confidence level. Although The Duration-Based Tests of independence conducted revealed that the models are correctly specified since in all cases the null hypotheses were accepted. This means that the probability of an exception on any day did not depends on the outcome of the previous day. Finally, both the unconditional (Kupiec) and conditional (Christoffersen) coverage tests for the correct number of exceedances for both Total stock returns and cleansed returns. The tests revealed rejection of the models at 1% level of significance. This confirms that unconditional (Kupiec) and conditional (Christoffersen) coverage tests for the correct number of exceedances are reliable compared to the Duration-Based Tests of independence. Therefore we recommend that shareholders and investors in Total Nigeria plc are to remain and continue to investment in Total Nigeria plc because if there is any form of losses, the price of the stock has the potentials to improve in the future. Again, though the risk is high at 99% confidence level, this in line with the financial theory that states that an asset with high expected risk would pay higher return on the average.
ARTICLE | doi:10.20944/preprints201807.0202.v1
Subject: Engineering, Other Keywords: bioremediation; Ex-situ; Aspergillus niger; Pseudomonas aeruginosa; Total Petroleum Hydrocarbon; crude oil; biostimulant efficiency; Kinetics
Online: 11 July 2018 (13:13:04 CEST)
The study was done to investigate the kinetics of first order bioremediation. The effectiveness of remediating soils polluted with raw crude oil and treated crude oil using Aspergillus niger (fungi) and Pseudomonas aeruginosa (bacteria) were investigated. Eight systems of 500g soil sample were polluted with both raw and treated crude oil. Four systems were polluted with 40g treated crude oil while the other remaining four systems were polluted with 40g raw crude oil. Two systems with raw crude and treated crude were left as control (RCC and TCC). Raw crude samples were treated with Aspergillus niger only (RCA) and Pseudomonas aeruginosa (RCP) while treated crude samples were also treated with same (TCA) and (TCP) only. The last two systems were treated with both Pseudomonas aeruginosa and Aspergillus niger (RCAP and TCAP). The first order bioremediation kinetics and biostimulant efficiency for these systems were studied by monitoring Total Petroleum Hydrocarbon (TPH). At the end of the bioremediation period, the results obtained showed that treated crude oil polluted soil generally remediated faster and better than raw crude oil polluted soil. The highest level of bioremediation occurred in systems amended with both Pseudomonas aeruginosa and Aspergillus niger which had about 98% TPH decrease.
ARTICLE | doi:10.20944/preprints202205.0306.v1
Subject: Engineering, Energy & Fuel Technology Keywords: promising areas of research; bibliometric analysis; Journal of Petroleum Science and Engineering; Web of Science; clustering
Online: 23 May 2022 (11:56:28 CEST)
This article identifies promising research areas on the PETROLEUM SCIENCE topic via bibliometric analysis of the 2018-2021 publications in the highly cited Journal of Petroleum Science and Engineering, which is included in the Journal Citation Reports Section: ENERGY & FUELS — Q2 Quartile, ENGINEERING, PETROLEUM — Q1 Quartile. Bibliometric metadata from Web of Science were used for 866 articles in 2018, 1,142 — in 2019, 1,138 — in 2020, and 1,832 in 2021. The clustering of articles was performed using the texts of the Title, Abstract, Keywords, and Keywords Plus fields. The demo version of the Lingo3G algorithm was used. For the two major clusters, the most promising research topics were determined by comparing the titles of the 350 most cited and 350 least cited articles for each year. The hypothesis that low-cited papers often have the same subject matter as high-cited papers of previous years is discussed.
REVIEW | doi:10.20944/preprints202202.0361.v1
Subject: Engineering, Energy & Fuel Technology Keywords: Hydropower; Wind, Solar; Geothermal; Firewood; Nuclear; Petroleum; Peat; Non-solid biomass; Solid biomass; Energy systems; Human energy; Animal energy
Online: 28 February 2022 (12:25:14 CET)
We live in the world that is completely entangled on energy and thus, Humankind can no longer do without it, power. With electricity being the main form of energy today, this has increased the complexity of our life today. In Uganda, electricity generation is mainly through hydropower which put the country in the bottleneck of over dependence on one source of energy. Yet, there are many energy systems out there that country can diversify its electricity generation. Therefore, the need to understand, the level of development and utilization of various energy systems has been the underlying question for this present study. Comprehensive literature survey was conducted from the electronic databases including ScienceDirect, Wiley, Sage, Scopus, Taylor & Francis, and Google Scholar. The publications in form of reports, conference papers, working papers, discussion papers, journal articles, book sections and textbooks were considered in this study. In total, 11 energy systems including human and animal energy, solid biomass (firewood), hydropower, wind, geothermal, solar, nuclear, peat, coal, petroleum, and non-solid biomass (methanol, hydrogen, ethanol, biodiesel, and biogas) are described. The current and the future development and utilization of these energy systems has been described. The challenges with their development and utilization were elaborated and the solution the challenges were presented. The hydropower with River Nile being the main river for large hydropower plant construction is the dominance energy system in Uganda. Nuclear energy will be the salvation for the country’s electric energy supply in the near future. Therefore, Uganda needs to bet big on nuclear energy.
ARTICLE | doi:10.20944/preprints202002.0223.v1
Subject: Mathematics & Computer Science, Applied Mathematics Keywords: carbon emissions; energy consumption; technology efficiency; Gini index; generalised entropy index; fossil fuels; non-fossil fuels; petroleum; coal; natural gas
Online: 16 February 2020 (15:20:21 CET)
Primary energy consumption is one of the key drivers of global CO2 emissions that, in turn, heavily depend on the efficiency of involved technologies. Either the improvement in technology efficiency or the expansion of non-fossil fuel consumption require large investments. The planning and financing of such investments, by policy makers or global energy firms, require, in turn, reliable measures of associated global spreads and their evolution in time. In this paper, our main contribution is the introduction of index measures for accessing global spreads (that is, measures of inequality or inhomogeneity in the statistical distribution of a related quantity of interest) of technology efficiency and CO2 emission in primary energy consumption. These indexes are based on the Gini index, as used in economical sciences, and generalised entropy measures. Regarding primary energy sources, we consider petroleum, coal, natural gas and non-fossil fuels. Between our findings, we attest some stable relations in the evolution of global spreads of technology efficiency and CO2 emission, and a positive relation between changes in global spreads of technology efficiency and use of non-fossil fuel.
COMMENTARY | doi:10.20944/preprints201612.0150.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Environmental Assessment Report (EAR); environmental health; Environmental Management/Environmental Management Systems (EM/EMS) Model; Environmental Management Plan (EMP); Multinational oil companies (MOCs); Niger Delta; Ogoni; Ogoniland; Shell Petroleum Development Company (SPDC); United Nations Environmental Program (UNEP)
Online: 30 December 2016 (07:39:30 CET)
In August 4 2011, United Nations Environmental Program (UNEP) submitted an unprecedented, scientific, groundbreaking Environmental Assessment Report (EAR) of Ogoniland, to the Nigerian government. This was the outcome of a 14–month intensive evaluation of the extent of pollution. It was intended that UNEP’s recommendations would be implemented to restore the devastated environment, on the one hand, and on the other, counteract the numerous environmental health issues that have for decades, plagued Ogoniland. However, five years post EAR, and, despite the seriousness of the situation, no significant resolution has occurred, both on the part of the government, and on the part of Shell Petroleum Development Company (SPDC) or Shell. To date, millions of Niger Delta residents, particularly those living in the oil-bearing communities, continue to suffer severe consequences. Although, the assessment was conducted in Ogoniland, other communities in the Niger Delta are also affected. This article explores prevailing issues, using Ogoniland (a microcosm of the Niger Delta) as an example. A multidisciplinary approach for sustainable mitigation of environmental health risks in the Niger Delta is paramount, and Environmental Management tools offer valuable strategies. Adopting UNEP’s recommendations for addressing environmental health problems requires implementing the Environmental Management/Environmental Management System (EM/EMS) model.