Browse
Subjects
Records with Subject: Environment
Showing records 201 to 225 of 3420. [First] Page: 5 6 7 8 9 10 11 12 13 Last
A Transient Productivity Prediction Model for Horizontal Wells Coupled with Oil and Gas Two-Phase Seepage and Wellbore Flow
Wenqi Ke, Wei Luo, Shiyu Miao, Wen Chen, Yaodong Hou
August 3, 2023 (v1)
Subject: Environment
Keywords: capacity prediction, horizontal wells, saturation pressure, transient model, two-phase seepage
Capacity prediction is the basis for the optimization of oil and gas well production work systems and parameter optimization design. Horizontal wells are becoming increasingly popular for oil and gas extraction. However, the seepage law of reservoirs produced with horizontal wells is more complicated than that of reservoirs produced with vertical wells, especially when the bottom hole flowing pressure or formation pressure is less than the saturation pressure of crude oil in the reservoir. Oil and gas two-phase seepage can occur in a part or all areas of the wellbore and reservoir. Because the oil and gas two-phase seepage characteristics of reservoir oil well production will be reduced—possibly greatly reduced—the formation seepage law is complex. Thus, it is very important to better predict the horizontal well capacity. To address this, a method and process of establishing a transient calculation model of two-phase flow in horizontal wells are introduced in detail from three aspects:... [more]
Diving into Fish Valorisation: Review Opportunities and Analyzing Azorean Fish Data
Nádia Valério, Margarida Soares, Cândida Vilarinho, Manuela Correia, Joana Carvalho
August 3, 2023 (v1)
Subject: Environment
Keywords: blue economy, circular economy, fish by-product valorisation, fish waste, sustainable marine sources, the Azores
In response to the exponential growth in world population, there has been a striking surge in the volume of discarded fish worldwide. This surge is particularly evident in the fish processing industry, where a substantial amount of waste is generated, posing significant environmental concerns. Consequently, the repurposing and utilisation of these waste materials have emerged as pivotal processes for the preservation of marine resources. By employing innovative strategies, valuable products can be extracted from these fish by-products, offering not only economic advantages but also contributing to mitigating environmental impacts. This comprehensive literature review focuses on exploring diverse avenues for using fish waste and extracting high-value materials such as bioactive peptides, collagen, and enzymes, elucidating their potential applications across various industries. The literature review also demonstrates the possibility of extracting various bio-compounds from highly diverse... [more]
A Novel Pattern Recognition based Kick Detection Method for Offshore Drilling Gas Kick and Overflow Diagnosis
Yang Xu, Jin Yang, Zhiqiang Hu, Dongsheng Xu, Lei Li, Chao Fu
August 3, 2023 (v1)
Subject: Environment
Keywords: gas invasion, kick, offshore drilling, overflow, pattern recognition, threshold method
In offshore drilling, accidents such as gas invasion, overflow, and kicks are unavoidable, and they can escalate into blowouts and other catastrophic events, resulting in casualties and significant economic losses. Therefore, ensuring drilling safety requires precise monitoring of gas invasion and overflow. Currently, most overflow monitoring methods used at drilling sites are based on threshold criteria. However, the monitoring parameters obtained during actual drilling operations often contain noise signals, which makes it challenging for threshold-based methods to achieve a balance between improving accuracy and minimizing false positives. This paper proposes a novel method called Pattern-Recognition-based Kick Detection (PRKD) for diagnosing overflow in offshore drilling. The PRKD method utilizes the overflow evolution process by integrating multiphase flow calculations, data filtering theory, pattern recognition theory, the Bayesian framework, and other theoretical models. By anal... [more]
Folic Acid and Its Role in Oral Health: A Narrative Review
Cristina-Crenguța Albu, Maria-Angelica Bencze, Anca-Oana Dragomirescu, Ioana Suciu, Mihaela Tănase, Ştefan-Dimitrie Albu, Emily-Alice Russu, Ecaterina Ionescu
August 3, 2023 (v1)
Subject: Environment
Keywords: cytokines, folic acid, MTHFR C677T mutation, oral health, orofacial clefts, periodontal disease
Vitamins, exogenous organic compounds that play a vital role in metabolic reactions, and fundamental powerful antioxidants with a crucial role in the genetic transcription process, are considered essential nutritional factors. Folic acid (FA), also known as folate, or Vitamin B9, plays an indispensable role in various intracellular reactions, being the main pawn, with a strong impact on medical and dental science. The aim of this paper mainly focuses on presenting the latest and most advanced aspects related to the following topics: (1) the resonance that FA, and more specifically FA deficiency, has at the level of the oral cavity; (2) the elements involved in the molecular landscape, which reflect the interaction and the possible mechanisms of action, through which FA influences oral health; and (3) the particular processes by which FA deficiency causes certain clinical conditions. Moreover, we aim to draw the attention and trigger the curiosity of health professionals on the need to... [more]
Study on the Preparation of ZnFeO4 by Roasting Zinc-Containing Gossan Ore
Jinlin Yang, Zongyu Li, Xingnan Huo, Hangyu Li, Shizhen Liao, Shaojian Ma, Hengjun Li
August 3, 2023 (v1)
Subject: Environment
Keywords: gossan ore, preparation, roasting, ZnFeO4
Gossan ore is typically abandoned after mining, which not only increases mining production costs but also wastes mineral resources, and its long-term accumulation can easily lead to environmental pollution hazards. Therefore, this paper takes zinc-containing gossan ore as the research object and, based on the high content of zinc and iron minerals in gossan ore, this study conducts a roasting experiment to prepare ZnFeO4. X-ray diffraction is used to characterize and analyze the ZnFeO4 sample prepared by roasting zinc-containing gossan ore. The experimental results indicate that controlling the particle size of the roasted ore sample to −0.074 mm can effectively remove impurities and facilitate the reaction. The influence of roasting temperature and time on the formation of ZnFeO4 is remarkable. The conditions for roasting zinc-containing gossan ore to maximize the ZnFeO4 content are as follows: −0.074 mm particle size ore sample, reaction zinc/iron molar ratio of 1:2, mechanical activ... [more]
The Sustainability Study and Exploration in the Building Commercial Complex System Based on Life Cycle Assessment (LCA)−Emergy−Carbon Emission Analysis
Jun Cao, Yangfei Zhu, Junxue Zhang, Hechi Wang, Haohao Zhu
August 3, 2023 (v1)
Subject: Environment
Keywords: building system, LCA-carbon emission, LCA-emergy, Renewable and Sustainable Energy
This paper focuses on the sustainable exploration of building systems, which combines ecological concepts and low-carbon designs for a comprehensive sustainability assessment investigation. The study employed the Life Cycle Assessment (LCA)-Emergy and Life Cycle Assessment (LCA)-Carbon emission methods to discuss a range of topics, including the main contributing factors, sustainability index verification, sensitivity analysis, and potential improvement measures. From an ecological sustainability perspective, the results indicate that the building operation stage plays a critical role, accounting for approximately 45% of the entire emergy in the building commercial complex. The sustainable index (ESI) is 0.354, which is below the standard of 1. Moreover, the building operation stage also significantly contributes to carbon emissions, particularly in the 50th anniversary of operation. Based on these findings, the study recommends two potential strategies to improve the ecological state... [more]
Behavior of Carbothermal Dephosphorization of Phosphorus-Containing Converter Slag and Its Resource Utilization
Shuai Tong, Chenxiao Li, Liqun Ai, Shuhuan Wang, Shuai Zhang
August 2, 2023 (v1)
Subject: Environment
Keywords: carbothermal reduction, CO2 emission, converter slag, dephosphorization, ferrophosphorus
Phosphorus-containing converter slag is a common waste in the iron and steel industry, and has the characteristics of high generation and low secondary-utilization values; however, the high-phosphorus content in converter slag limits its ability to be recycled during the steelmaking process. In this study, the dephosphorization behavior of converter slag by carbothermal reduction was studied through experiments and thermodynamic calculations. The results showed that the gas product of the converter slag produced by carbothermal reduction was mainly P2, and that part of P2 entered the iron phase to generate iron phosphate compounds. With the increase in Fe content, the amount of P2 also increased, which may provide a suitable new direction for the production of ferrophosphorus. Based on the carbothermal reduction theory, a new “circulating steelmaking process of converter steel slag gasification” was proposed and applied to Chengde Iron and Steel Group Co., Ltd. (Chengde, China). The in... [more]
The Decomposition of Dilute 1-Butene in Tubular Multilayer Dielectric Barrier Discharge Reactor: Performance, By-Products and Reaction Mechanism
Chao Li, Xiao Zhu, Shiqiang Wang, Yafeng Guo, Yu Du, Yinxia Guan, Shiya Tang
August 2, 2023 (v1)
Subject: Environment
Keywords: 1-butene, decomposition, dielectric barrier discharge reactor, O2 concentration, oxidation mechanism
Butene is a typical component of exhaust gas in the petrochemical industry, the emission of which into the atmosphere would lead to air pollution. In this study, a tubular multilayer dielectric barrier discharge (TM-DBD) reactor was developed to decompose 1-butene at ambient pressure. The experimental results show that a decomposition efficiency of more than 99% and COx selectivity of at least 43% could be obtained at a specific energy density of 100 J/L with an inlet concentration of 1-butene ranging from 100 to 400 ppm. Increasing the volume ratio of O2/N2 from 0 to 20% and the specific energy density from 33 to 132 J/L were beneficial for 1-butene destruction and mineralization. Based on organic byproduct analysis, it was inferred that the nitrogenous organic compounds were the main products in N2 atmosphere, while alcohol, aldehyde, ketone, acid and oxirane were detected in the presence of O2. In addition, the contents of formaldehyde, acetaldehyde, ethyl alcohol, acetic acid and p... [more]
Adsorptive Removal of Dye (Methylene Blue) Organic Pollutant from Water by Pine Tree Leaf Biomass Adsorbent
Tushar Kanti Sen
August 2, 2023 (v1)
Subject: Environment
Keywords: equilibrium isotherm model, methylene blue dye adsorption, pine tree leaf biomass adsorbent, thermodynamics
In this laboratory batch adsorption study, the raw pine tree leaf biomass solid waste adsorbent material was used for the removal of methylene blue (MB) dye from water at different physicochemical process conditions. The characteristics of adsorbents were determined for particle size, surface area, the existence of functional group identification, and the morphology of the adsorbent surface. The adsorption was performed at different process conditions, which include solution pH, dye concentrations, adsorbent doses, and temperature, respectively. In this study, it was found that MB dye adsorption increased with increases in solution pH and adsorbate MB dye concentration but decreased with adsorbent doses and temperature at fixed process conditions. The Langmuir isotherm model was best fitted with the experimental equilibrium data, with a higher linear regression coefficient (R2) value of 99.9% among the two widely used Langmuir and Freundlich adsorption isotherm model equations. The max... [more]
Effects of Nitrate Recycle on the Sludge Densification in Plug-Flow Bioreactors Fed with Real Domestic Wastewater
Jie-Fu Wang, Zhao-Hui An, Xue-Yao Zhang, Bob Angelotti, Matt Brooks, Zhi-Wu Wang
August 2, 2023 (v1)
Subject: Environment
Keywords: granular sludge, MLE, NRCY, PFR startup
The impact of adding a modified Ludzack−Ettinger (MLE) configuration with Nitrate Recycle (NRCY) on continuous-flow aerobic granulation has yet to be explored. The potential negative effects of MLE on sludge densification include that: (1) bioflocs brought by NRCY could compete with granules in feast zones; and (2) carbon addition to anoxic zones could increase the system organic loading rates and lead to higher feast-to-famine ratios. Two pilot-scale plug flow reactor (PFR) systems fed with real domestic wastewater were set up onsite to test these hypotheses. The results showed that MLE configuration with NRCY could hinder the sludge granulation, but the hindrance could be alleviated by the NRCY location change which to some extent also compensates for the negative effect of higher feast-to-famine ratios due to carbon addition in MLE. This NRCY location change can be advantageous to drive sludge densification without a radical washout of the sludge inventory, and had no effects on the... [more]
Distribution Characteristics of Heavy Metals in Different Particle Size Fractions of Chinese Paddy Soil Aggregates
Cang Gong, Yang Shao, Min Luo, Diandou Xu, Lingling Ma
August 2, 2023 (v1)
Subject: Environment
Keywords: heavy metals, leachability, paddy soil, particle size fraction, soil aggregates
In recent years, the migration and transformation of heavy metals (HMs) in soil has become a hot issue. Soil particle size has an important effect on the environmental behavior of HMs in soil. The distribution of HMs in soil is strongly affected by the size of a soil aggregate. In this study, paddy samples in both cultivated and uncultivated soils were collected from Anhui Province, China. The soils were sieved into six particle size fractions (diameters of >4000, 4000−2000, 2000−1000, 1000−250, 250−53, and 4000 μm particles. Moreover, the concentrations of Cd, Cr, Pb, and As were elevated in cultivated paddy soils compared to uncultivated soils. The accumulation of HMs in all paddy soils increased with decreasing particle size. Although the smallest particle size fractions accounted for only 5.65−17.28%, they provided the highest distribution factor (DF) of Cr (1.35), As (1.25), Cd (1.28), and Pb (1.38). The highest contributions of HMs came from the coarser fractions (>2000 μm); howe... [more]
Comparative Analysis of Paddy Harvesting Systems toward Low-Carbon Mechanization in the Future: A Case Study in Sri Lanka
P. D. Kahandage, S. D. S. Piyathissa, Reza Ariesca, Namgay, Riaru Ishizaki, E. J. Kosgollegedara, G. V. T. V. Weerasooriya, Tofael Ahamed, Ryozo Noguchi
July 13, 2023 (v1)
Subject: Environment
Keywords: combine harvesting, effective field capacity, greenhouse gas emissions, manual harvesting, reaper harvesting
In this study, three paddy harvesting systems, manual harvesting of paddy (MHP), reaper harvesting of paddy (RHP), and combine harvesting of paddy (CHP), were evaluated considering field capacities, field efficiencies, time and fuel consumption, mechanization indices, greenhouse gas emissions, straw availability, and direct and indirect costs. Field experiments were conducted in the North Central Province of Sri Lanka. The effective field capacity, field efficiency and fuel consumption of the combine harvester were 0.34 hah−1, 60.8%, and 34.1 Lha−1, respectively, and those of the paddy reaper were 0.185 hah−1, 58.2%, and 3.8 Lha−1, respectively. The total time consumed by MHP, RHP, and CHP were 76.05 hha−1, 39.76 hha−1, and 2.94 hha−1, respectively. The highest energy utilization was recorded by the CHP, at 1851.09 MJha−1, while MHP recorded the lowest at 643.20 MJha−1. The direct cost of the MHP was 1.50 and 1.52 times higher than those of the CHP and RHP, respectively. MHP recorded t... [more]
Existing Stature and Possible Outlook of Renewable Power in Comprehensive Electricity Market
Shreya Shree Das, Jayendra Kumar, Subhojit Dawn, Ferdinando Salata
July 13, 2023 (v1)
Subject: Environment
Keywords: environment, global power scenario, grid-interactive power, India power scenario, renewable energy sources, tariff
The massive growth in power demand and the sharp decay in the availability of conventional energy sources forces society to move toward renewable power consumption. The rise in renewable energy utilization is one of the greatest strategies involved in making the environment clean, green, and emission-free. The investment cost is slightly high for this kind of resource, but their running costsare very minimal, which encourages power producers to invest in renewable power plants. Power producers always focus on their economic profit and possible feasibilities before the investment in a new power plant setup. Wind, small hydro, and solar photovoltaics have been considered the foremost efficient and feasible renewable sources. In 2021, the worldwide renewable power capacity had grown to 17%, despite supply chain disturbances and surges in prices. The renewable power market set a target of achieving a 95% increment in global power capacity by 2026. Hence, humankind should consider wind, hyd... [more]
Effects of Bio-Coal Briquette for Residential Combustion on Brown Carbon Emission Reduction
Juan Qi, Jianjun Wu
July 13, 2023 (v1)
Subject: Environment
Keywords: bio-coal briquette, BrC, combustion, residential solid fuel
Biomass burning is an important source of brown carbon (BrC) which poses high-risk threats to human health and the environment. In this study, bio-coal briquette (coal mixed with biomass), a promising solid fuel for residential combustion, is proven to be a clean fuel which can effectively reduce BrC emission. First of all, an orthogonal experiment with three factors and three levels on the physical property of bio-briquette was carried out to identify the optimal preparation conditions including the ratio of biomass to anthracite, particle size and molding pressure. Then a combustion experiment of the bio-coal briquetted was implemented in a simulated residential combustion system. BrC emission factors (EFs) were calculated based on the detected black carbon (BC) concentration by an aethalometer, and other optical characteristics for organic components of extract samplers, such as mass absorption efficiency (MAE) and absorption angstrom index (AAE), were also explored. Lastly, composi... [more]
Reclamation Potential of Onsite Wastewater Post-Treatment with Microalgae: Chemical Elements Perspective
Dobril Valchev, Irina Ribarova, Blagoy Uzunov, Maya Stoyneva-Gärtner, Valentina Lyubomirova
July 13, 2023 (v1)
Subject: Environment
Keywords: algae, circular technology, decentralized sewerage systems, fertilizer, irrigation, nature-based solutions, onsite wastewater treatment, resource recovery
Algae-based wastewater treatment is a promising technology with various applications for excess biomass such as biofertilizer production or valuable elements extraction. The benefits of the technology have been discussed for larger wastewater treatment plants (WWTPs), but the use of microalgae in decentralized wastewater treatment has been barely reported. The current study screens the possible resource recovery potential of onsite technology, which adds algae-based post-treatment to the conventional biological treatment of domestic wastewater. The effluent from the onsite sequencing batch reactor (SBR) of a household was further processed in laboratory conditions using an SBR technology with two local monocultures of algae—Klebsormidium nitens (Kützing) Lokhorst and Tetradesmus obliquus (Turpin) M. J. Wynne. The decant and the generated algal biomass were analyzed in terms of their element content. The post-treated effluent has a slightly better quality for irrigation purposes than th... [more]
Phycoremediation of Synthetic Dyes Laden Textile Wastewater and Recovery of Bio-Based Pigments from Residual Biomass: An Approach towards Sustainable Wastewater Management
Vivek Kumar Nair, Koushalya Selvaraju, Saurabh Samuchiwal, Farah Naaz, Anushree Malik, Pooja Ghosh
July 7, 2023 (v1)
Subject: Environment
Keywords: algal-bacterial consortia, bio-based pigments, dye degradation, phycoremediation, textile wastewater
The textile industry is a growing sector worldwide and has immense opportunity in terms of providing employment and boosting a nation’s economy. However, there exist severe environmental risks associated with textile effluents that impact the surrounding ecosystem. This review offers an approach for sustainable water management using phycoremediation to treat dye-laden wastewater and recover bio-based pigments from the residual biomass. Microalgae such as Chlorella, Scenedesmus, Phormidium, and macroalgae like Sargassum, Enteromorpha, and Codium has been extensively used in several phycoremediation-based studies, and their residual biomass could be a potent source for extraction of bio-based pigments. This review also recommends studies involving the algal-bacterial consortia approach for treating dye-laden wastewater as an alternative to conventional, biobased methods. The outcome of this study will provide policymakers and researchers with new insight to manage water and wastewater r... [more]
Geochemical Characteristics and Development Model of the Coal-Measure Source Rock in the Kuqa Depression of Tarim Basin
Xiujian Ding, Tianze Gao, Xianzhang Yang, Zhenping Xu, Changchao Chen, Keyu Liu, Xueqi Zhang
July 7, 2023 (v1)
Subject: Environment
Keywords: coal-measure source rock, depositional environment, input of terrestrial organic matter, Jurassic system, Kuqa Depression, sedimentary rate
The development model of the coal-measure source rock may be different from that of the lacustrine source rock. The depositional environment of the coal-measure source rock is dominated by weak oxidation and weak reduction, and the majority of the organic material originates from terrestrial higher plants. Taking the Jurassic coal-measure source rock in the Kuqa Depression as the research object, the geochemical characteristics of the source rock are comprehensively analyzed, the primary controlling elements of source rock development are made clear, and the development model of the coal-measure source rock is established. This study contributes to the field of source rock prediction and oil and gas exploration. The lithology of the coal-measure source rock in the Kuqa Depression is mainly mudstone, carbonaceous mudstone, and coal, which are medium- to good-quality source rocks, and the organic matter type is mainly II2 and III. Terrestrial organic matter is a key factor in controlling... [more]
Chemical and Biological Characterisation of Orange (Citrus sinensis) Peel Extracts Obtained by Subcritical Water
Tanja Brezo-Borjan, Jaroslava Švarc-Gajić, Simone Morais, Cristina Delerue-Matos, Francisca Rodrigues, Ivana Lončarević, Biljana Pajin
July 7, 2023 (v1)
Subject: Environment
Keywords: biological and chemical characterisation, subcritical water extraction, sweet orange peel
Orange peels, generally considered as waste, were treated with subcritical water (SWE)—a green technology and environmentally friendly extraction process—at different temperatures (120−200 °C) and extraction times (5−60 min). The extracts which were obtained were chemically and biologically characterised to evaluate this potential source of bioactive compounds. The extracts total phenolics content (TPC) and total flavonoids contents (TFC), as well as total antioxidant capacity (TAC), DPPH radical scavenging activity, and total carbohydrate content, were determined by UV spectrophotometry. The pectin content was quantified by a gravimetric method. The dietary fibre content was investigated, and a phytochemical screening assay was performed. The extract obtained at 120 °C for 5 min displayed the highest TPC (45.45 mg GAE/g DW), TFC (9.29 mg RE/g DW), and TAC (130.47 mg AAE/g DW), indicating that relatively low temperatures and extremely short extraction times can be used in SWE to obtain... [more]
Increasing Surface Functionalities of FeCl3-Modified Reed Waste Biochar for Enhanced Nitrate Adsorption Property
Peijing Kuang, Yubo Cui, Zhongwei Zhang, Kedong Ma, Wanjun Zhang, Ke Zhao, Xiaomeng Zhang
July 7, 2023 (v1)
Subject: Environment
Keywords: iron modification, mechanism, nitrate adsorption property, reed waste biochar, surface functionalities
Ferric chloride (FeCl3) modified reed straw-based biochar was synthesized to remove nitrate from aqueous solutions and achieve waste recycling. The adsorption of nitrate onto Fe-RBC-600 adsorbents could be described by the pseudo-second-order kinetic model and fitted to Langmuir adsorption, and the maximum adsorption capacity predicted using the Langmuir model was 272.024 mg g−1. The adsorbent characterization indicated that a high temperature of 600 °C and an oxygen-poor environment could develop a hydrophobic surface and O-containing functional groups on the biochar, which provided more binding sites for Fe3+/Fe2+ attachment and increased the surface functionality of Fe-RBC-600 with iron oxide formation. The increasing surface functionality successfully enhanced the nitrate adsorption property. The mechanism of nitrate adsorption was mainly attributed to the physical adsorption onto the positive surface and sequential chemical reduction by Fe2+, and the electrostatic adsorption by pr... [more]
Monitoring and Analysis of the Driving Forces of Changes in the Ecological Environment of a Mining Area of Western China from 1986 to 2022
Lu Bai, Yingming Yang, Kai Zhang, Shuyu Liu, Gang Liu
July 7, 2023 (v1)
Subject: Environment
Keywords: coal mining area, ecological environment change, remote sensing ecological index
The remote sensing ecological index (RSEI) has been widely used in the rapid monitoring and evaluation of the regional ecological environment; however, the research on the main factors that cause changes in RSEI and the impact of human activities in the mining area on RSEI is not often explored. To this end, this paper selected the Landsat (TM/OLI) series of remote sensing images from 1986 to 2022; extracted the four important indicators of the normalized difference vegetation index (NDVI), the wetness component of the tasseled cap transformation (WET), normalized difference built-up and soil index (NDBSI), and land surface temperature (LST); calculated the remote sensing ecological index (RSEI) based on the principal component analysis method; monitored and evaluated the ecological environment changes in the Shendong Mining Area for a period of 36 years; and analyzed the driving forces that cause these ecological environment changes. The results show the following: (1) The ecological... [more]
Preliminary Study on the Feasibility of Radiation Technique for Mural Protection
Zesheng Wang, Min Luo, Yang Shao, Lingling Ma, Minghong Wu
July 7, 2023 (v1)
Subject: Environment
Keywords: CIE L*a*b* color space, cultural heritage preservation, decontamination, electron beam, mural blocks, Raman spectra, scotch tape test
Murals are a significant cultural heritage of humanity, and one of the conservation studies is to control the growth of microorganisms. General biocide agents can be used to preserve murals while also providing new organic carbon sources and increasing environmental pollution. In recent years, radiation technology has shown promising prospects for use in heritage protection. Five microorganisms often found in murals were irradiated with an electron beam in this study, and six mineral pigments were tested for color change, Raman spectra and pigment layer cohesion after irradiation. The result showed that irradiation at 20 kGy can basically eliminate Pseudomonas citronellolis, Bacillus sporothermodurans, Streptomyces vinaceus, and Streptomyces griseolus from the culture medium, but only inhibited the growth of Penicillium flavigenum. Lead white pigment showed a color difference of 5.56 (∆E*97) after irradiation, but lead tetroxide, azurite, malachite, ferrous oxide, and cinnabar showed n... [more]
Coffee Pulp: A Sustainable and Affordable Source for Developing Functional Foods
Angélica Pérez Calvo, Nelson Paz Ruiz, Zuly Delgado Espinoza
July 7, 2023 (v1)
Subject: Environment
Keywords: circular economy, coffee, environmental impact, experimental design, Renewable and Sustainable Energy, value added
Coffee cultivation in the Department of Cauca, Colombia, is vital for much of the department’s economy. Coffee processing generates waste, such as pulp, which accounts to about 40% of the fresh fruit. Currently, in most cases in Cauca, coffee byproducts are discarded, and, in other cases, the coffee pulp is used for fertilizers, generating environmental problems due to its decomposition. This research aims to design a process for supplying a functional food in the form of an energy bar based on coffee pulp and other components of the region, such as quinoa and panela, helping to mitigate the environmental impact of coffee production. Our research included four phases. First, we determined the study area; in the second phase, we studied an energy bar’s nutritional and physical characteristics. Then, the requirements and specifications of the bar were defined, and the authors documented the process diagram, variables within the process, and the quality plan. Finally, the authors conducte... [more]
Life Cycle Assessment of Fuel Ethanol Production from Food Waste in Consideration of By-Product Utilization
Jun Zhou, Hongzhi Ma, Pin Lv, Wei Su, Qunhui Wang, Ming Gao, Heyang Qin
July 4, 2023 (v1)
Subject: Environment
Keywords: by-product, environmental implications, Ethanol, food waste, life cycle assessment
In this paper, a life cycle assessment was used to evaluate fuel ethanol production from food waste with a capacity of 20 tons/day. The energy and pollution emissions during the whole process were recorded and compared by the method of electricity conversion to standard coal. Different indicators, such as GWP (global warming potential), ODP (ozone depletion potential), AP (acid potential), EP (possibility of eutrophication), POCP (photochemical oxidation potential), and DUST (dust), were used to perform an environmental impact analysis with and without by-product utilization. The result shows that the indicator sequence under the weighted factor sequence was AP > DUST > GWP > ODP > EP > POCP. The consideration of by-products decreased the values of GWP, AP, and DUST significantly; EP declined slightly; ODP and POCP increased; and the overall energy output was negative. The consideration of by-product utilization was determined to be environmentally friendly.
Economic−Financial Assessment of Seawater Desalination Plants in Northern Chile to Reduce Hydric Scarcity and a Proposal for the Environmental and Sustainable Use of Brine Waste by Cultivating the Microalga Dunaliella salina to Produce β-Carotene
Tomas Gabriel Bas, Rodrigo Fariña, Fernanda Gallardo, Macarena Vilches
July 4, 2023 (v1)
Subject: Environment
Keywords: brine, business model, desalination plant, Dunaliella salina, freshwater, hydric scarcity, north of Chile, waste, β-carotene
Climate change and global warming generate serious consequences and disturbances by drastically modifying historical temperature and precipitation patterns. Water scarcity is one of the most revealing phenomena of these instabilities. This transdisciplinary bibliometric and economic−financial research focuses on analyzing two aspects: first, the feasibility of implementing seawater desalination plants as a solution to water scarcity in northern Chile. Investment and amortization costs of the desalination plants were determined (NPV-IRR-IRP). NPV showed a positive value indicating a recovery of the initial investment and a surplus over profitability. The IRR was higher than the discount rate calculated for NPV, which showed that the investment project was accepted. The IRP indicated that the initial investment of the plant would be recovered in 3.7 years. Second, an innovative and environmentally sustainable solution to the brine (NaCl) waste generated by desalination plants is proposed... [more]
Recycling of Chrome-Containing Waste from a Mining and Processing Plant to Produce Industrial Products
Yerbulat Tastanov, Nuriya Serzhanova, Almagul Ultarakova, Nurzhan Sadykov, Zhadyra Yerzhanova, Aisha Tastanova
July 4, 2023 (v1)
Subject: Environment
Keywords: chromium oxide, concentrate, gravity concentration, nitrogen–magnesium fertilizer, slime tailings, thermal sulfatization
Prolonged development of ore deposits, ore beneficiation and metallurgical smelting of concentrates result in the accumulation of wastes, forming large-scale dumps and sludge ponds negatively affecting the environment and human health. The creation and introduction of industrial waste treatment technologies will make it possible to dispose of them with the production of valuable commercial products and improve the environmental situation. In a research article on chemical beneficiation with the subsequent gravitational beneficiation of chrome-containing slurry tailings of Donskoy Ore-Mining and Beneficiation Plant (DOMBP), which processes chrome ore of the Kempirsay deposit in the Republic of Kazakhstan, Aktobe region, having considerable stocks of such waste is presented. The chromium-containing slurry tailings were heat-treated at 1100 °C, sintered with ammonium sulfate, water and sulfuric acid in a defined ratio at 300 °C, and then the resulting sinter was leached with water at 90 °... [more]
Showing records 201 to 225 of 3420. [First] Page: 5 6 7 8 9 10 11 12 13 Last
[Show All Subjects]