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Records with Subject: Environment
Showing records 26 to 50 of 3342. [First] Page: 1 2 3 4 5 6 Last
Control-Volume-Based Exergy Method of Truncated Busemann Inlets in Off-Design Conditions
Meijun Zhu, Shuai Zhou, Yang Liu, Zhehong Li, Ziyun Chen
June 7, 2024 (v1)
Subject: Environment
Keywords: Busemann inlet, entropy production, exergy analysis, off-design condition, streamline tracing technique
A scramjet engine consisting of several components is a highly coupled system that urgently needs a universal performance metric. Exergy is considered as a potential universal currency to assess the performance of scramjet engines. In this paper, a control-volume-based exergy method for the Reynolds-averaged Navier−Stokes solution of truncated and corrected Busemann inlets was proposed. An exergy postprocessing code was developed to achieve this method. Qualitative and quantitative analyses of exergies in the Busemann inlets were performed. A complete understanding of the evolution process of anergy and the location where anergy occurs in the inlet at various operation conditions was also obtained. The results show that the exergy destroyed in the Busemann inlet can be decomposed into shock wave anergy, viscous anergy and thermal anergy. Shock wave anergy accounts for less than 4% of the total exergy destroyed while thermal anergy and viscous anergy, in a roughly equivalent magnitude,... [more]
Green Plasticizer for Poly(vinyl chloride) Re-Granulate Production: Case Study of Sustainability Concept Implementation
Marija M. Vuksanović, Milena Milošević, Ivan Dimitrijević, Gordana Milentijević, Ljiljana Babincev, Jelena Gržetić, Aleksandar Marinković, Milutin Milosavljević
June 7, 2024 (v1)
Subject: Environment
Keywords: green plasticizers, mechanical property, PET glycolysis, recycled PVC
The increase in waste polymer recycling has helped in promoting sustainability, and together with the use of renewable raw materials, it has become a widespread concept with positive effects on both the economy and ecology. Accordingly, the aim of this study was the synthesis of “green” plasticizers, marked as LA/PG/PET/EG/LA, formed from waste poly(ethylene terephthalate) (PET) and bio-based platform chemicals propylene glycol (PG) and levulinic acid (LA). The structure of the obtained plasticizers was complex, as confirmed by results from nuclear magnetic resonance (NMR) and Fourier-transform infrared spectroscopy (FTIR) analysis. The LA/PG/PET/EG/LA plasticizers and waste poly(vinyl chloride) (PVC) were used in an optimized technology for PVC re-granulate production. The hardness of the PVC-based material with “green” plasticizers, in comparison to commercial plasticizer dioctyl terephthalate (DOTP), increased by 11.3%, while migration decreased. An improved material homogeneity and... [more]
Experimental Study on Pressure Oscillations of Direct-Contact Condensation between Saturated Steam and Droplets at Sub-Atmospheric Pressure
Yuanlin Jing, Chenhao Wang, Qunwu Huang, Yiping Wang, Yangyang Yu
June 7, 2024 (v1)
Subject: Environment
Keywords: direct-contact condensation, droplets, pressure oscillation, saturated steam, the auto power spectrum
In this paper, under the background of low-temperature steam waste heat recovery technology, the pressure oscillation characteristics of direct-contact condensation between continuously falling droplets and saturated steam at sub-atmosphere pressure were studied. An experimental device of pressure oscillation based on an acceleration oscillation sensor was established to investigate the influence of vapor pressure and fluid velocity on the oscillation characteristics of direct-contact condensation. The results showed that as the absolute pressure increases, the peak value of oscillation decreases gradually and the time-domain periodic waveform becomes fluctuating. When the liquid flow rate is low, the condensation oscillation shows a single-peak waveform and the dominant frequency moves towards a higher frequency. When the liquid velocity increases gradually, the RMS (root mean square) of pressure oscillation remains unchanged at first and then decreases obviously. The dominant frequen... [more]
Exergy-Based Improvements of Sustainable Aviation Fuels: Comparing Biorefinery Pathways
Pablo Silva Ortiz, Silvio de Oliveira Jr, Adriano Pinto Mariano, Agnes Jocher, John Posada
June 7, 2024 (v1)
Subject: Environment
Keywords: biojet fuel production, biorefinery performance measurement, exergy and environmental assessment
The aeronautical sector faces challenges in meeting its net-zero ambition by 2050. To achieve this target, much effort has been devoted to exploring sustainable aviation fuels (SAF). Accordingly, we evaluated the technical performance of potential SAF production in an integrated first- and second-generation sugarcane biorefinery focusing on Brazil. The CO2 equivalent and the renewability exergy indexes were used to assess environmental performance and impact throughout the supply chain. In addition, exergy efficiency (ηB) and average unitary exergy costs (AUEC) were used as complementary metrics to carry out a multi-criteria approach to determine the overall performance of the biorefinery pathways. The production capacity assumed for this analysis covers 10% of the fuel demand in 2020 at the international Brazilian airports of São Paulo and Rio de Janeiro, leading to a base capacity of 210 kt jet fuel/y. The process design includes sugarcane bagasse and straw as the feedstock of the bi... [more]
Enzymatic Pretreatment of Slaughterhouse Wastewater: Application of Whole Lipolytic Cells of Rhizopus oryzae Produced from Residual Vegetable Oil
Willian S. M. Reis, Heitor B. S. Bento, Ana K. F. Carvalho, Ernandes B. Pereira
June 6, 2024 (v1)
Subject: Environment
Keywords: hydrolysis, lipase, whole cell
This study assessed the application of whole lipolytic cells in the pretreatment of slaughterhouse wastewater to reduce its lipid content. The fungal biomass of Rhizopus oryzae was evaluated in the hydrolysis of slaughterhouse wastewater containing high lipid concentrations, focusing on the biomass’s concentration and the effect of using an emulsifier and surfactant. The use of the whole-cells lipase of Rhizopus oryzae grown in a residual vegetable oil medium proved effective in the hydrolysis of slaughterhouse wastewater, generating concentrations of free fatty acids (FFA) ranging from 40.36 to 90.14 mM. The action of lipase in the hydrolysis of slaughterhouse residues indicated its effectiveness in pretreating lipid-rich liquid residues, potentially boosting the microbiota of this anaerobic treatment. The results showed that lipase activity without surfactant exhibited a similar performance to that of Triton X-100 in the hydrolysis of liquid residues. However, the combination of lipa... [more]
Extraction Kinetics of Pyridine, Quinoline, and Indole from the Organic Phase with Natural Deep Eutectic Solvents and Separation Study Using a Centrifugal Extractor
Dmitriy V. Lobovich, Inna V. Zinov’eva, Nikita A. Milevskii, Artak E. Kostanyan, Yulia A. Zakhodyaeva, Andrey A. Voshkin
June 6, 2024 (v1)
Subject: Environment
Keywords: centrifugal extractors, extraction kinetics, indole, mass transfer, natural deep eutectic solvents, pyridine, quinoline
In this study, the kinetics of extracting pyridine, quinoline, and indole from model fuels using natural deep eutectic solvents (NaDES) composed of carboxylic acids, xylitol, and water were investigated under static conditions. This research marks the first examination of extraction kinetics in this context. The key kinetic parameters of the extraction process were identified. Notably, it was observed that the mass transfer coefficient for indole was in the range of 3.4 × 10−6 to 1.2 × 10−6, depending on NaDES. That is significantly lower, by an order of magnitude, than for pyridine and quinoline under identical experimental conditions. The study revealed that, under specific conditions, where thermodynamic equilibrium for indole cannot be reached, it becomes possible to achieve kinetic separation of the components. The presented experimental data obtained on a centrifugal extractor showed a decrease in the degree of indole extraction with increasing flow: Extraction efficiency decreas... [more]
Pristine and UV-Weathered PET Microplastics as Water Contaminants: Appraising the Potential of the Fenton Process for Effective Remediation
Marin Kovačić, Antonija Tomić, Stefani Tonković, Anamarija Pulitika, Josipa Papac Zjačić, Zvonimir Katančić, Boštjan Genorio, Hrvoje Kušić, Ana Lončarić Božić
June 6, 2024 (v1)
Subject: Environment
Keywords: Fenton process, microplastics, oxidation, polyethylene terephthalate, removal, weathering
Polyethylene terephthalate (PET) microplastics constitute a significant portion of plastic pollution in the environment and pose substantial environmental challenges. In this study, the effectiveness of the Fenton process and post-oxidation coagulation for the removal of non-weathered and UV-weathered PET microplastics (PET MPs) were investigated. A response surface methodology was used to investigate the interplay between PET concentration and ferrous ion (Fe2+) concentration. The models revealed an intricate interplay between these variables, highlighting the need for a balanced system for optimal PET MP removal. For non-weathered PET, the simultaneous increase in the concentrations of both PET microplastics and Fe2+ was found to enhance the removal efficiency. However, this synergistic effect was not observed in UV-weathered PET, which also demonstrated a more pronounced effect from the Fe2+ concentration. The statistical analysis provided a strong basis for the validity of the mode... [more]
Assessing Phytoremediation Potential: Dominant Plants in Soils Impacted by Polymetal(loid)lic Mining
Boxin Wang, Juan Hou, Xueyong Wu, Xuekui Niu, Fengping Zhou
June 6, 2024 (v1)
Subject: Environment
Keywords: adaption strategies, ecological restoration, native dominant plants, phytoremediation, polymetal(loid)lic contamination
Phytoremediation, an ecological approach aimed at addressing polymetal(loid)lic-contaminated mining soils, has encountered adaptability challenges. Dominant plant species, well-suited to the local conditions, have emerged as promising candidates for this purpose. This study focused on assessing the phytoremediation potential of ten plant species that thrived in heavy metal(loid)-contaminated mining soils. This investigation covered nine heavy metal(loid)s (As, Cu, Cd, Cr, Hg, Ni, Pb, Sn, and Zn) in both plants and rhizosphere soils. The results revealed a significant impact of mining activities, with heavy metal(loid) concentrations surpassing the Yunnan Province’s background levels by 1.06 to 362 times, highlighting a significant concern for remediation. The average levels of the heavy metal(loid)s followed the order of As (3.98 × 103 mg kg−1) > Cu (2.83 × 103 mg kg−1) > Zn (815 mg kg−1) > Sn (176 mg kg−1) > Pb (169 mg kg−1) > Cr (68.1 mg kg−1) > Ni (36.2 mg kg−1) > Cd (0.120 mg kg−1)... [more]
Permeability Effect and Nonlinear Coupling Characteristics of Rock−Soil Interaction with Water
Ning Liang, Ziyun Wang
June 6, 2024 (v1)
Subject: Environment
Keywords: internal damage, nonlinear coupling, rock and soil, seepage effect
The seepage effect of rock and soil in the process of encountering water follows a nonlinear coupling law between water and rock. According to the permeability of rock and soil during softening with water, changes in particles in rock and soil are related to permeability mechanisms. Based on the assumption of connection between particles in rock and soil, changes in particles before and after water infiltration, the mechanism of water−rock interaction, and the damage to rock and soil are analyzed herein. Combined with fractal theory and percolation theory, the random failure characteristics and nonlinear behavior of water in rock and soil are studied. At the same time, with the help of Fluent 17.0 software, the seepage process of rock samples in water is numerically simulated and analyzed. Taking the permeability coefficient of rock samples, the mass flow rate of water, and the internal pore water pressure of rock samples as tracking objects, it is found that there are obvious nonlinea... [more]
Procedure for Aggregating Indicators of Quality and Life-Cycle Assessment (LCA) in the Product-Improvement Process
Andrzej Pacana, Dominika Siwiec
June 6, 2024 (v1)
Subject: Environment
Keywords: carbon footprint, LCA, mechanical engineering, production engineering, quality, sustainable development
Sustainable product development requires combining aspects, including quality and environmental. This is a difficult task to accomplish. Therefore, procedures are being sought to combine these aspects in the process of product improvement. Therefore, the objective of the investigation was to develop a procedure that supports the integration of quality-level indicators and life-cycle assessment (LCA) to determine the direction of product improvement. The procedure involves determining the quality indicators based on the expectations of the customer, which are subsequently processed using the formalised scoring method (PS). A life-cycle assessment index is determined for the main environmental impact criterion. According to the proposed mathematical model, these indicators are aggregated, and this process takes into account their importance in terms of product usefulness and environmental friendliness. Interpretations of the results and the direction of product improvement are from the r... [more]
Occurrence and Removal of Microplastics in Tertiary Wastewater Treatment Plants: A Case Study of Three Plants in Zhengzhou, China
Yang Li, Tongtong Qin, Xinjie Bai, Wenjing Wu, Xudong Chen, Minghui Shen, Liwen Qin, Yanyan Dou, Xuejun Duan
June 6, 2024 (v1)
Subject: Environment
Keywords: microplastics, removal efficacy, tertiary treatment process, wastewater treatment plant
Microplastics have been widely detected in wastewater treatment plants, but there is still a significant dearth of research data on the removal efficiency of microplastics in such plants. The present study focused on three wastewater treatment plants situated in Zhengzhou, China. On-site sampling and Raman spectrum detection techniques were employed to identify microplastics in both wastewater and sludge samples, while the removal efficiency of microplastics was quantified for each plant. Results showed that the abundance of microplastics in influent exhibited ranging from 147.5 ± 2.6 to 288.8 ± 11.8 n/L, while the range in sludge samples was from 12,024.7 ± 1737.0 n/kgdw to 20,818.4 ± 5662.0 n/kgdw. The removal efficiencies of microplastics in the three WWTPs ranged from 76.2% to 91.2%. The primary components of microplastics were generally identified as fibers ranging in size from 10 to 100 μm. The samples collectively exhibited a total of seven distinct colors, with the predominant... [more]
Fabrication and Characterisation of Sustainable 3D-Printed Parts Using Post-Consumer PLA Plastic and Virgin PLA Blends
Mohammad Raquibul Hasan, Ian J. Davies, Alokesh Paramanik, Michele John, Wahidul K. Biswas
June 5, 2024 (v1)
Subject: Environment
Keywords: additive manufacturing, blended filament, circular economy, mechanical properties, post-consumer PLA waste
Sustainable manufacturing practices are becoming increasingly necessary due to the growing concerns regarding climate change and resource scarcity. Consequently, material recycling technologies have gradually become preferred over conventional processes. This study aimed to recycle waste polylactic acid (PLA) from household-disposed cups and lids to create 3D-printed parts and promote sustainable manufacturing practices. To achieve this, the current study utilised virgin and post-consumer PLA (PC-PLA) (sourced from household waste) blends. The PC-PLA wastes were shredded and sorted by size with the aid of a washing step, resulting in a filament with a 1.70 ± 0.5 mm diameter without fragmentation or dissolution. A 50:50 wt.% blend of virgin PLA (vPLA) and PC-PLA was selected as the standard recycling percentage based on previous research and resource conservation goals. The study investigated the impact of three 3D printing parameters (layer height (LH), infill density (I), and nozzle t... [more]
An Experimental Study on the Seepage Characteristics of Rough Fractures in Coal under Stress Loading
Yafei Luo, Yongjian Zhu, Fei Huang
June 5, 2024 (v1)
Subject: Environment
Keywords: coalbed methane, nonlinear seepage, pressure gradient, rough fracture, stress loading
Fracture and stress environments significantly affect the flow of coalbed methane. Under stress, fracture deformation and damage occur, which change the original fracture characteristics and lead to changes in gas flow characteristics. The change in gas pressure gradient makes the fluid flow obviously nonlinear. Using linear flow theory to describe the fracture flow leads to a large error in predicting coalbed methane productivity. In this study, seepage tests on fractured coal are carried out under different stresses and gas pressure gradients, the nonlinear flow and changes in related parameters are analyzed, and the applicability of the nonlinear flow equation is evaluated. The resulting seepage of the gas flow in the fracture under stress is obviously nonlinear, which gradually increases with increasing effective stress and gas pressure gradient. When the Forchheimer equation is used to characterize the nonlinear seepage in fractures, the coefficients increase with increasing effec... [more]
Modeling Challenges in Low-Carbon Manufacturing Adoption Using the ISM-MICMAC Approach: A Case of Green Tech Projects of the Chinese Automotive Industry
Hanqin Yu, Yi Zhang, Naveed Ahmad
June 5, 2024 (v1)
Subject: Environment
Keywords: challenges, environmental sustainability, ISM and MICMAC, low-carbon manufacturing, sustainable automotive industry, zero carbon
In addressing the issue of climate change, the Chinese government has established a definitive objective to attain its peak carbon emissions by 2030 and strive for carbon neutrality by 2060. This effort aims to progressively achieve a state of net-zero carbon dioxide (CO2) emissions. In the given scenario, this research examines challenges in promoting low-carbon manufacturing (LCM) within the Chinese automotive sector, specifically in the context of Green Tech projects. In view of greater emphasis on environmental sustainability and technological innovation, this study aims to uncover challenges restraining the adoption of LCM in one of the world’s largest automotive markets, China. A three-step methodology was adopted by incorporating a literature review, the Delphi method, Interpretive Structural Modeling (ISM), and MICMAC analysis. In the first stage, relevant articles were selected scientifically to identify the main challenges in previous studies by following the relevant keyword... [more]
Assessment of Fungal Resistance and Preservative Retention in Microwave-Pretreated Norway Spruce Wood
Sauradipta Ganguly, Marko Petrič, Sadhna Tripathi, Davor Kržišnik
June 5, 2024 (v1)
Subject: Environment
Keywords: antifungal properties, microwave treatment, Norway spruce wood, preservative leaching, wood durability
This study investigates the effectiveness of microwave treatment (MW) on the antifungal properties of Norway spruce wood and the leaching of preservatives. Given the environmental and health concerns about conventional wood preservatives, this study evaluates microwave treatment as a sustainable pretreatment to limit the leaching of preservatives from wood. In the experiment, wood samples were treated with microwaves at five different energy levels before being impregnated with copper−ethanolamine- and boron-based preservatives. We assessed preservative retention by leaching tests and assessed the resistance of the wood to fungal attack. The results show that MW treatment improves the uptake and fixation of preservatives, reduces leachability, and significantly improves the durability of an otherwise perishable wood against fungal attack. This study emphasises the potential of microwave treatment for wood preservation. It offers an environmentally friendly approach to extending the lif... [more]
Long-Term Ampacity Prediction Method for Cable Intermediate Joints Based on the Prophet Model
Zhiqiang Zhang, Wenping Liu, Lingcheng Zeng, Song He, Heng Zhou, Jiangjun Ruan
June 5, 2024 (v1)
Subject: Environment
Keywords: cable intermediate joint, dynamic ampacity, temperature inversion, time series
The development of power grids is hindered by the limited transmission capacity of cable equipment, necessitating the accurate prediction of dynamic ampacity for cable expansion. This study focuses on the 110 kV cable intermediate joint, employing radial and axial inversion techniques for real-time conductor temperature inversion. Utilizing the Prophet time series model, we predict environmental changes and propose a dynamic ampacity evaluation method for cable intermediate joints. Experimental validation confirms the model’s accuracy, with prediction errors under 10 K, demonstrating its potential for enhancing cable system reliability and power grid development.
A Thermo-Economic Measure of Sustainability
Umberto Lucia, Giulia Grisolia
June 5, 2024 (v1)
Subject: Environment
Keywords: bio-economy, happiness, human development index, Renewable and Sustainable Energy, thermodynamics, wealth
Recently, an improvement of the United Nations Human Development Index (HDI), named the Thermodynamic Human Development Index (THDI), has been introduced to link socio-economics to environmental and technical pillars of sustainable development. In this paper, the THDI is linked to the Kaya identity to bring out the quantities useful in energy economics and to obtain a clearer tool for the evaluation of sustainability. Moreover, the THDI has been normalized for use as an index for the analysis of sustainability. The component related to environmental emissions, which is included in the THDI, can be linked to the Kaya identity. This linkage allows us to use the THDI for the analysis of scenarios, which is useful for evaluating the possible impacts of any future actions on the development of countries.
Evaluation of the Bioenergy Potential of Blends (Green Coconut Shells and Fish Scales) as a Feedstock in Thermochemical Processes for Clean Energy Production
Ayrton Pablo Raiol Monroe, Arthur Vinicius Sousa Silva, Mariana Silva Melo, Julie Brenda Santos da Silva, Ramón Raudel Peña Garcia, Maria Alexsandra de Sousa Rios, Waldir Antônio Bizzo, Glauber Cruz
June 5, 2024 (v1)
Subject: Environment
Keywords: fibrous structure, socioenvironmental impacts, solid residues, thermal behavior
Brazil is among the world’s largest producers of green coconut, which contributes to inappropriate disposal and socioenvironmental impacts. Concomitantly, some of its coastal cities produce a great diversity of fish and large amounts of solid waste. This paper reports on the use of samples of fish scales (100FS) and green coconut shells (100GCS) and their mixtures in 75%FS:25%GCS (B25), 50%FS:50%GCS (B50), and 25%FS:75%GCS (B75) proportions and quantification of their Higher Heating Values (HHV) and Lower Heating Values (LHV), and Ultimate (UA) and Proximate Analyses (PA). Their thermal behavior was investigated by thermogravimetry (TG/DTG) and differential scanning calorimetry (DSC), whereas scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transformed infrared (FTIR) were employed for analyses of their physicochemical and morphostructural properties. When compared to in natura samples, SEM images of the blends detected a st... [more]
Thermoeconomic Modeling as a Tool for Internalizing Carbon Credits into Multiproduct System Analysis
José Joaquim C. S. Santos, Pedro Rosseto de Faria, Igor Chaves Belisario, Rodrigo Guedes dos Santos, Marcelo Aiolfi Barone
June 5, 2024 (v1)
Subject: Environment
Keywords: carbon credit, carbon market, cost allocation, environmental cost, multiproduct system, thermoeconomic modeling
In the context of emissions, carbon dioxide constitutes a predominant portion of greenhouse gases (GHGs), leading to the use of the term “carbon” interchangeably with these gases in climate-related discussions. The carbon market has emerged as a pivotal mechanism for emission regulation, allowing industries that struggle to meet emission reduction targets to acquire credits from those who have successfully curbed their emissions below stipulated levels. Thermoeconomics serves as a tool for analyzing multiproduct systems prevalent in diverse sectors, including sugarcane and alcohol mills, paper and pulp industries, steel mills, and cogeneration plants. These systems necessitate frameworks for equitable cost/emission allocation. This study is motivated by the need to expand the scope of thermoeconomic modeling to encompass expenses or revenues linked with the carbon market. By utilizing a cogeneration system as a representative case, this research aims to demonstrate how such modeling ca... [more]
Study on the Fixation of Mulberry Leaf Tea in a Multiport Microwave System
Tao He, Fengxiu Li, Desheng Hou, Lin Wang, Dezhi Gou, Tao Hong, Zhengming Tang
June 5, 2024 (v1)
Subject: Environment
Keywords: coaxial probe, dielectric constant, microwave fixation, mulberry leaf tea, porous media
Microwaves have the advantages of faster heating speed, shorter fixation time, and less pollution in tea fixation. However, there are few studies on the microwave fixation of mulberry leaf tea, which is not conducive to the promotion of mulberry leaf tea production. In order to study the fixation of mulberry leaf tea, the coaxial probe method is used to measure the dielectric constant of mulberry leaves, and the relationship connecting the real and imaginary parts of the dielectric constant and the moisture content is obtained through fitting. Based on this, a multiphysics model for mulberry leaf fixation in a six-port microwave cavity is established, which combines the characteristics of mulberry leaves, multiport heating, and mobile heating techniques. The impact of some important parameters, such as the layout and position of input ports and the thickness of mulberry leaves on the fixation process, are studied. The results show that the mutual energy coupling between ports can be re... [more]
Application of Corn Straw, an Agro-Waste, to Remove Dyes in an Aqueous Medium, Producing Blue or Red Fibers
Andressa dos Santos, Anne R. Sotiles, Fauze J. Anaissi
June 5, 2024 (v1)
Subject: Environment
Keywords: agro-industrial residue, color stability, corn straw, dyeing artificial, Wastewater
The contaminant dyes that, even at low concentrations, may cause a series of adverse effects in humans and animals, and their removal by adsorption methods using alternative adsorbents as natural fibers, are regarded as a research topic that has become increasingly relevant. In this study, corn straw (CS), an agro-industrial residue, was used to remove dyes. The samples were characterized by ATR-FTIR, SEM-EDS, zeta potential, diffuse spectra, and colorimetry, before and after dye removal. The analyses allowed us to differentiate the morphology of CS after the treatment’s fiber on the adsorbent surface. The zeta potential showed a negative surface charge, but the acidic or alkaline treatment affected the surface charge of the sample, influencing the adsorption of cationic or anionic dyes. Adsorption data presented an increased removal when alkaline treatment was applied for the methylene blue (MB; qmax = 16.7 mg g−1), and the acid treatment was more effective for the Congo red (CR; qmax... [more]
Non-Thermal Plasma Technology for Further Purification of Flue Gas in the Resource Utilization Process of Waste Mercury Catalyst: A Case Study in Xinjiang, China
Qinzhong Feng, Kaiyue Wang, Shitong Yang, Jianbo Guo, Jun Chen, Tongzhe Wang, Liyuan Liu, Yang Chen
June 5, 2024 (v1)
Subject: Environment
Keywords: environmentally friendly, mercury-containing flue gas, non-thermal plasma technology, resource utilization process, waste mercury catalyst
This study aims to advance the recycling of mercury-containing waste and promote sustainable development within the polyvinyl chloride (PVC) industry. Our innovative system integrates pre-treatment technology (spraying potassium permanganate and demisting and dust removal) with efficient non-thermal plasma oxidation, resulting in excellent treatment efficiency, low cost, and simple operation. With a processing capacity of 3000 m3/h, the concentration of mercury emissions in flue gas can achieve the target of <0.01 mg/m3, boasting a removal efficiency exceeding 98%, which satisfies the standard “Emission standard of air pollutants for industrial kiln and furnace” (GB 9078-1996). Our results can provide technical support for the comprehensive purification of mercury-containing flue gas during the resource recovery process from mercury-containing waste. The application of our system can contribute to reducing mercury emissions in the PVC industry, lowering occupational exposure risks f... [more]
Exploring Safety of Machineries and Training: An Overview of Current Literature Applied to Manufacturing Environments
Maria Elena Del Giudice, Mahnaz Sharafkhani, Mario Di Nardo, Teresa Murino, Maria Chiara Leva
June 5, 2024 (v1)
Subject: Environment
Keywords: review, safety, safety of machinery, systematic literature review
A machine is described as an assembly that has a drive system installed or is planned to have a drive system installed and that is constituted of linked elements or components, at least one of which moves, that are connected for a particular application (ISO12100). Different types of risks are present in machines, and exposure to them can cause harm or even death. When risk has been adequately reduced, machinery safety considers a machine’s ability to complete its intended duty throughout its life cycle. A literature review was carried out using “safety of machinery” as a keyword, which produced an analysis of 29 papers published from 2008 to 2024. The papers were examined through bibliometric analysis of the year of publication, country, citation statistics, and study of the keywords. These studies were classified into accident analysis papers, papers focused on the normative, papers that addressed risk assessment tools, and papers that conducted quantitative research. In addition, a... [more]
Performance of Mg/Al and Zn/Al Hydroxide Double Lamellar-Bentonite for Removal of Anionic Azo Dye from Aqueous Solution
Mohammed Mustapha Bouhent, Kahina Bentaleb, Abdulrahman Al-Ameri, Ulrich Maschke
June 5, 2024 (v1)
Subject: Environment
Keywords: Adsorption, azoic orange II dye, bentonite, layered double hydroxides, wastewater treatment
This paper presents the preparation and characterization of bentonite coated with hydroxide double lamellar Mg/Al-bentonite and Zn/Al-bentonite as a potential adsorbent material. The coating process involved co-precipitation of mixed metal nitrate solution (Mg-Al) or (Zn-Al), followed by immersion of bentonite (B-Na+) dispersion. The structures and morphologies of the coated bentonites were characterized using XRD, FTIR, BET, and SEM analysis. The results of the BET analysis indicate that Mg/Al-bentonite and Zn/Al-bentonite have larger surface areas and pore volumes compared to bentonite alone. Specifically, the surface area of Mg/Al-bentonite is 209.25 m2/g with a pore volume of 0.423 cm3/g, while Zn/Al-bentonite has a surface area of 175.95 m2/g and a pore volume of 0.313 cm3/g. In contrast, the surface area and pore volume of bentonite alone are 110.43 m2/g and 0.132 cm3/g, respectively. The Mg/Al-bentonite reaches 85% uptake within 3 h (equivalent to 724.20 mg/g at 25 °C and pH 7),... [more]
Decision Making for Control of the Gasoline Fraction Hydrotreating Process in a Fuzzy Environment
Batyr Orazbayev, Alua Tanirbergenova, Kulman Orazbayeva, Meruert Berikbaeva, Samal Kaliyeva, Lyailya Kurmangaziyeva, Valentina Makhatova
June 5, 2024 (v1)
Subject: Environment
Keywords: decision making, fuzzy information, heuristic method, hydrotreating process, Pareto optimality principle
This article is devoted to the study of decision-making problems of hydrotreating process control in the production of high-quality gasoline under conditions of scarcity and fuzziness of the initial information, ultimately developing an approach to solve them. A systematic method is proposed that makes it possible to develop a package of mathematical models of a complex of interconnected units of chemical-technological systems based on available information of various types. Using the proposed system method, a package of models of the main interconnected units in which the hydrotreating process took place was developed. A decision-making problem was formulated to control the hydrotreating process in a fuzzy environment based on the developed system of models. By modifying the Pareto principle of optimality for fuzzy conditions, a heuristic method for solving the given decision-making problem was developed to control the hydrotreating process in a fuzzy environment. The novelty of the p... [more]
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