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Records with Subject: Environment
3296. LAPSE:2023.1906
Characteristics of Ecological Energy Carriers Used in Agricultural Technology
February 21, 2023 (v1)
Subject: Environment
Keywords: atomic emission spectrometry, ecological energy carriers, ecological transmission–hydraulic fluid, environmentally sensitive environments, laboratory test equipment, working fluids
This article focuses on the properties of ecological energy carriers, which are used in agricultural and forestry technology. The aim of the article is to describe the degradation of the working fluid from the point of view of the atomic emission spectrometer, which is used for the purpose of monitoring contaminants and additive elements. The working fluid examined was Shell Naturelle HF-E 46, a universal ecological transmission−hydraulic fluid, which was tested on laboratory test equipment. The laboratory measurement was performed for 200 h, during which the gear hydraulic pump with external gearing was cyclically loaded according to the Vickers standard. The analysis of the transmission−hydraulic fluid was performed after every 50 working hours, where the analysis of the working fluid showed that there were no significant changes in the properties of the working fluid and fluid is suitable for work in agricultural and forestry machines operating in environmentally sensitive environme... [more]
3297. LAPSE:2023.1887
Construction of Edge Computing Platform Using 3D LiDAR and Camera Heterogeneous Sensing Fusion for Front Obstacle Recognition and Distance Measurement System
February 21, 2023 (v1)
Subject: Environment
Keywords: 3D LiDAR (Light Detection and Ranging), edge computing, heterogeneous sensor fusion, object recognition, rigid body transformation, YOLOv4
This research aims to utilise heterogeneous sensor fusion using 3D Light Detection and Ranging (LiDAR) and cameras, combined with an object recognition system and a ranging system, to construct an edge computing platform such that a vehicle equipped with the platform can perform computations offline in real time. This work comprises two main sections: the first is heterogeneous fusion, and the second is obstacle recognition and ranging detection. To achieve heterogeneous sensor fusion, 3D−3D point matching was used to find rigid body transformation between two sensors and finally project the LiDAR 3D point cloud image onto the 2D image. For object recognition, YOLOv4-Tiny was used as the detection network. A lightweight network architecture and high computational speed could be effectively used on edge computing hardware with limited performance. Further, by drawing the bounding box, we could detect the point cloud within the bounding box to estimate the distance to the obstacle. For d... [more]
3298. LAPSE:2023.1863
A Mechanistic Study on the Anti-Corrosive Performance of Zinc-Rich Polyester/TGIC Powder Coatings
February 21, 2023 (v1)
Subject: Environment
Keywords: anti-corrosive, barrier, EIS, electrochemical impedance spectroscopy, galvanic, pigment, polyester, powder coatings, sacrificial anode, zinc-rich
Powder coatings represent an environmentally friendly VOC-free alternative to widely used solvent-borne zinc-rich coatings, with economic and ecological benefits. In particular, powder coatings have several advantageous properties, such as chemical resistance and mechanical strength. However, the performance and characteristics of polyester-based zinc-containing powder coatings remain unknown. In this study, the corrosion performance of polyester powder coatings containing up to 80% zinc is compared. Electrochemical and salt-spray testing results indicate that coatings formulated with 80% zinc demonstrate superior anti-corrosive properties than coatings with lower zinc dosages. Two distinct behavioral phases of the coating with 80% zinc were observed by measurements of open circuit potential (OCP) and polarization resistance (Rp) during immersion tests—a phase indicative of a barrier effect and a phase consistent with galvanic protection. The evolution of the coating was further charac... [more]
3299. LAPSE:2023.1861
Sustainability Assessment of the Utilization of CO2 in a Dielectric Barrier Discharge Reactor Powered by Photovoltaic Energy
February 21, 2023 (v1)
Subject: Environment
Keywords: carbon capture and utilization (CCU), CO2 conversion, DBD, non-thermal plasma
The direct activation of diluted CO2 in argon was studied in a co-axial dielectric barrier discharge (DBD) reactor powered by photovoltaic energy. The influence of the initial CO2 and argon concentration on the CO2 decomposition to form CO was investigated using a copper-based catalyst in the discharge zone. It was observed that the CO2 conversion was higher at lower CO2 concentrations. The presence of the diluent gas (argon) was also studied and it was observed how it has a high influence on the decomposition of CO2, improving the conversion at high argon concentrations. At the highest observed energy efficiency (1.7%), the CO2 conversion obtained was 40.2%. It was observed that a way to enhance the sustainability of the process was to use photovoltaic energy. Taking into account a life cycle assessment approach (LCA), it was estimated that within the best-case scenario, it would be feasible to counterbalance 97% of the CO2 emissions related to the process.
3300. LAPSE:2023.1843
Degradation of the UV Filter Benzophenone-4 by Ferrate (VI) in Aquatic Environments
February 21, 2023 (v1)
Subject: Environment
Keywords: benzophenone-4, ferrate (VI), kinetics, oxidation
This work demonstrates the potential utility of ferrate(VI)-based advanced oxidation processes for the degradation of a representative UV filter, BP-4. The operational parameters of oxidant dose and temperature were determined with kinetic experiments. In addition, the effects of water constituents including anions (Cl−, HCO3−, NO3−, SO42−), cations (Na+, K+, Ca2+, Mg2+, Cu2+, Fe3+), and humic acid (HA) were investigated. Results suggested that the removal rate of BP-4 (5 mg/L) could reach 95% in 60 min, when [Fe(VI)]:[BP-4] = 100:1, T = 25 °C and pH = 7.0, The presence of K+, Cu2+ and Fe3+ could promote the removal of BP-4, but Cl−, SO42−, NO3−, HA and Na+ could significantly inhibit the removal of BP-4. Furthermore, this Fe(VI) oxidation processes has good feasibility in real water samples. These results may provide useful information for the environmental elimination of benzophenone-type UV filters by Fe(VI).
3301. LAPSE:2023.1830
Treatment of PBDEs from Soil-Washing Effluent by Granular-Activated Carbon: Adsorption Behavior, Influencing Factors and Density Functional Theory Calculation
February 21, 2023 (v1)
Subject: Environment
Keywords: Adsorption, density functional theory calculation, granular-activated carbon, polybrominated diphenyl ethers, soil-washing effluent, Triton X-100
Soil-washing is a potential technology for the disposal of soil contaminated by e-waste; however, the produced soil-washing effluent will contain polybrominated diphenyl ethers (PBDEs) and a large number of surfactants, which are harmful to the environment, so the treatment of PBDEs and the recycling of surfactants are the key to the application of soil-washing technology. In this study, coconut shell granular-activated carbon (GAC) was applied to remove PBDEs from Triton X-100 (TX-100) surfactant which simulates soil-washing effluent. The adsorption results show that, GAC can simultaneously achieve effective removal of 4,4′-dibromodiphenyl ether (BDE-15) and efficient recovery of TX-100. Under optimal conditions, the maximum adsorption capacity of BDE-15 could reach 623.19 μmol/g, and the recovery rate of TX-100 was always higher than 83%. The adsorption process of 4,4′-dibromodiphenyl ether (BDE-15) by GAC could best be described using the pseudo-second-order kinetic model and Freund... [more]
3302. LAPSE:2023.1809
Building Sector Issues in about 100 Years: End-Of-Life Scenarios of Carbon-Reinforced Concrete Presented in the Context of a Life Cycle Assessment, Focusing the Carbon Footprint
February 21, 2023 (v1)
Subject: Environment
Keywords: carbon fiber, carbon-reinforced concrete, end-of-life, LCA, recycling, reinforced concrete
Carbon-reinforced concrete (CRC) has the potential to play a pivotal role in optimizing the built environment and has therefore been experiencing a wave of research and development in the construction industry in recent years. The production of carbon fibers for CRC is energy-intensive, prompting the need to explore circular economy approaches (e.g., recycling at the End-of-Life (EoL)) to optimize the environmental performance of this material. Underdeveloped processes and a resulting lack of primary data regarding the recycling of CRC have hampered a comprehensive sustainability assessment of the novel composite building material. The novelty of this article is the detailed presentation of possible EoL scenarios for CRC and the detailed determination of the respective environmental impacts. This study aims to model EoL options within a Life Cycle Assessment (LCA), focusing on the EoL stage based on ISO 14040/44 using the GaBi ts 10.5.1.124 software and the CML2001 (2016) methodology.... [more]
3303. LAPSE:2023.1784
Coordination of Configurations of Technologically Integrated “European Green Deal” Projects
February 21, 2023 (v1)
Subject: Environment
Keywords: agricultural waste, configuration, coordination, environmentally friendly fuel, integrated projects, risks, value
An analysis of the state of affairs in the theory and practice of implementation of technologically integrated projects in various applied fields was carried out. The peculiarities of the implementation of the technologically integrated projects of the “European Green Deal” for the production of ecologically clean fuel from agricultural waste were analyzed. The expediency of developing a method of coordinating the configurations of technologically integrated “European Green Deal” projects for the production of ecologically clean energy from agricultural waste on the territory of a given region, taking into account their specific project environments, was substantiated. As a result of the conducted research, a method of coordinating configurations of the technologically integrated “European Green Deal” projects for the production of ecologically clean energy from agricultural waste in the territory of a given region, taking into account their specific project environment, was developed.... [more]
3304. LAPSE:2023.1775
Continuous Systems Bioremediation of Wastewaters Loaded with Heavy Metals Using Microorganisms
February 21, 2023 (v1)
Subject: Environment
Keywords: bioreactor studies, bioremediation, heavy metals, microorganisms, wastewater treatment
Heavy metal pollution is a serious concern of the modern era due to its widespread negative effects on human health and to the environment. Conventional technologies applied for the uptake of this category of persistent pollutants are complex, often expensive, and inefficient at low metal concentrations. In the last few years, non-conventional alternatives have been studied in search of better solutions in terms of costs and sustainability. Microbial adsorbents are one of the biomass-based sorbents that have extensively demonstrated excellent heavy metals removal capacity even at low concentrations. However, most of the carried-out research regarding their application in wastewater treatment has been performed in discontinuous systems. The use of microorganisms for the uptake of metal ions in continuous systems could be an important step for the upscale of the remediation processes since it facilitates a faster remediation of higher quantities of wastewaters loaded with heavy metals, i... [more]
3305. LAPSE:2023.1760
Environmental Benefits of Sleep Apnoea Detection in the Home Environment
February 21, 2023 (v1)
Subject: Environment
Keywords: Artificial Intelligence, computer-aided diagnosis, polysomnography, remote monitoring, sleep apnoea
Sleep Apnoea (SA) is a common chronic illness that affects nearly 1 billion people around the world, and the number of patients is rising. SA causes a wide range of psychological and physiological ailments that have detrimental effects on a patient’s wellbeing. The high prevalence and negative health effects make SA a public health problem. Whilst the current gold standard diagnostic procedure, polysomnography (PSG), is reliable, it is resource-expensive and can have a negative impact on sleep quality, as well as the environment. With this study, we focus on the environmental impact that arises from resource utilisation during SA detection, and we propose remote monitoring (RM) as a potential solution that can improve the resource efficiency and reduce travel. By reusing infrastructure technology, such as mobile communication, cloud computing, and artificial intelligence (AI), RM establishes SA detection and diagnosis support services in the home environment. However, there are conside... [more]
3306. LAPSE:2023.1745
The Radiation Shielding Performance of Polyester with TeO2 and B2O3
February 21, 2023 (v1)
Subject: Environment
Keywords: attenuation coefficient, effective atomic number, HPGe, polyester, TeO2
In this research, polymers were fabricated through combining polyester, boron oxide (B2O3), and Tellurium oxide (TeO2). B2O3 has good neutron absorption and TeO2 is not only highly dense (5.670 g/cm3) but also environment-friendly, compared to PbO, as well as being a good photon absorber. The radiation protection features for five investigated samples were examined utilizing an HPGe detector and point sources Am-241, Cs-137, and Co-60. The accuracy of the experimental setup of this experiment was proven through the linear attenuation coefficient (LAC) values obtained from the theoretical (XCOM) and experimental (HPGe) values of the newly developed polymers. The attained results showed that the values of LAC decrease with increasing energy. Moreover, at low energy, a noteworthy increase was found for the LAC values with the addition of TeO2. Due to the increase in TeO2 content of the polymers, the value of the half value layer (HVL) decreases from 6.073−4.193 cm at energy 0.662 MeV, fro... [more]
3307. LAPSE:2023.1744
An Overview of Emerging Cyanide Bioremediation Methods
February 21, 2023 (v1)
Subject: Environment
Keywords: anaerobic biodegradation, cyanide, electro-bioremediation, microbial fuel cell technology, omics
Cyanide compounds are hazardous compounds which are extremely toxic to living organisms, especially free cyanide in the form of hydrogen cyanide gas (HCN) and cyanide ion (CN−). These cyanide compounds are metabolic inhibitors since they can tightly bind to the metals of metalloenzymes. Anthropogenic sources contribute significantly to CN− contamination in the environment, more specifically to surface and underground waters. The treatment processes, such as chemical and physical treatment processes, have been implemented. However, these processes have drawbacks since they generate additional contaminants which further exacerbates the environmental pollution. The biological treatment techniques are mostly overlooked as an alternative to the conventional physical and chemical methods. However, the recent research has focused substantially on this method, with different reactor configurations that were proposed. However, minimal attention was given to the emerging technologies that sought... [more]
3308. LAPSE:2023.1726
Morula Tree: From Fruit to Wine through Spontaneous Fermentation and the Potential of Deriving Other Value-Added Products
February 21, 2023 (v1)
Subject: Environment
Keywords: marula fruit wine, marula fruits, marula juice, Sclerocarya birrea, wine fermentation
(Morula tree) is one of the indigenous trees bearing wild fruits with various applications in the African communities. Wine is a globally known beverage usually made from grapes; however, recently, other fruits, including wild fruits with a considerable amount of sugars, can be used for making wines. The marula fruit wine is also important in many communities for cultural activities and can be enjoyed by people of varying age groups depending on the age of the product. In recent years, there has been growing interest in shifting from traditional marula winemaking to developing technologies for the marula winemaking process and commercialisation. The process of marula winemaking is similar to the production of grape wines, which entails collection, selection and washing of the fruits; extraction of the juice and mashing; formation and removal of the scum; and ultimately spontaneous fermentation of the resulting juice. The new process in marula winemaking would take into consideration th... [more]
3309. LAPSE:2023.1713
An Emergy-Based Sustainability Method for Mechanical Production Process—A Case Study
February 21, 2023 (v1)
Subject: Environment
Keywords: data analysis, emergy, improvement, mechanical production processes
To promote the sustainability of mechanical production process, this study proposes an emergy-based sustainability evaluation method to evaluate the resource utilization and environmental pollution of the mechanical production process. Firstly, this study constructs the sustainability evaluation index system of the mechanical production process from the perspectives of economy and environment. Secondly, an emergy analysis method-based sustainable evaluation of the mechanical production process is constructed. Finally, taking the gear manufacturing process as an example, the method is tested. The results show that this method can effectively quantify and identify the sustainability of the gear manufacturing process and provide effective feedback to improve the process. The resulting improvements can aid in reconsidering the economic and environmental factors, improving the production efficiency and the sustainability of the production process, and reducing the difficulty of operating th... [more]
3310. LAPSE:2023.1690
A Systematic Review on Waste as Sustainable Feedstock for Bioactive Molecules—Extraction as Isolation Technology
February 21, 2023 (v1)
Subject: Environment
Keywords: bioactive molecules, Biomass, biorefinery, circular economy, Extraction, residue, secondary metabolite, waste
In today’s linear economy, waste streams, environmental pollution, and social−economic differences are increasing with population growth. The need to develop towards a circular economy is obvious, especially since waste streams are composed of valuable compounds. Waste is a heterogeneous and complex matrix, the selective isolation of, for example, polyphenolic compounds, is challenging due to its energy efficiency and at least partially its selectivity. Extraction is handled as an emerging technology in biorefinery approaches. Conventional solid liquid extraction with organic solvents is hazardous and environmentally unfriendly. New extraction methods and green solvents open a wider scope of applications. This research focuses on the question of whether these methods and solvents are suitable to replace their organic counterparts and on the definition of parameters to optimize the processes. This review deals with the process development of agro-food industrial waste streams for bioref... [more]
3311. LAPSE:2023.1683
In Situ Synthesis of Zero-Valent Iron-Decorated Lignite Carbon for Aqueous Heavy Metal Remediation
February 21, 2023 (v1)
Subject: Environment
Keywords: carbothermal reduction, heavy metal removal, in situ synthesis, lignite, ZVI
Lignite’s large abundance, physicochemical properties and low cost are attractive for industrial wastewater remediation. However, directly applying lignite for wastewater treatment suffers low efficiency. Here, we synthesize highly efficient zero-valent iron (ZVI)-decorated lignite carbon through the in-situ carbonization of a lignite and FeCl2 mixture for heavy metal removal. The effect of carbonization temperature on the morphology, structure and crystallite phases of ZVI-decorated lignite carbons (ZVI-LXs) was investigated. At an optimized temperature (i.e., 1000 °C), ZVI particles were found evenly distributed on the lignite matrix with the particles between 20 to 190 nm. Moreover, ZVI particles were protected by a graphene shell that was formed in situ during the carbonization. The synthesized ZVI-L1000 exhibited higher Cu2+, Pb2+ and Cd2+ stripping capacities than pristine lignite in a wide pH range of 2.2−6.3 due to the surface-deposited ZVI particles. The maximum Langmuir adsor... [more]
3312. LAPSE:2023.1674
Approach to the Technical Processes of Incorporating Sustainability Information—The Case of a Smart City and the Monitoring of the Sustainable Development Goals
February 21, 2023 (v1)
Subject: Environment
Keywords: SDGs, sustainability information, technological processes
Currently, the concern for achieving and fulfilling the Sustainable Development Goals (SDGs) is a constant in advanced societies. The scientific community and various organisations are working on obtaining an information system that will make it possible to offer the necessary value to this type of sustainability information. The article aims to incorporate criteria on the technology used in the reporting system, specifically in collecting the different types of data and generating other interfaces. The methods described here are carried out on a specific case study, a Smart City, showing the different types of data that exist and the possible interfaces that allow objective monitoring of the achievement of the SDGs. It is, therefore, a descriptive study of a process whose results are the establishment of criteria concerning the different data sources as well as the generation of a set of interfaces that motivate the monitoring that can be carried out in a specific city to observe its... [more]
3313. LAPSE:2023.1664
A Sustainable Integration Approach of Chlor-Alkali Industries for the Production of PVC and Clean Fuel Hydrogen: Prospects and Bangladesh Perspectives
February 21, 2023 (v1)
Subject: Environment
Keywords: chlor-alkali plant integration, chlorine and H2 utilization, clean fuel, environmental sustainability, PVC market
The chlor-alkali industries produce caustic soda (NaOH), chlorine (Cl2), and hydrogen (H2) as primary products. In 2021, the global chlor-alkali market was valued at $63.2 billion. The article evaluates the global aspects of chlor-alkali industries and prospects for Bangladesh. The current production capacity of NaOH from the chlor-alkali industries in Bangladesh is around 282,150 metric tons/year (MT/y). The by-products, chlorine (Cl2) of 250,470 MT/y and hydrogen (H2) of 7055 MT/y, are produced domestically. The local demand of Cl2 is 68,779 MT/y. However, there are no systematic utilizations of the residual Cl2 and vented H2, which threatens the sustainability of the chlor-alkali industries. The article prefigures that a 150,000 MT/y PVC plant can utilize 45.2 % of residual Cl2 of chlor-alkali plants, which would be an economical and environmental milestone for Bangladesh. The residual Cl2 can earn revenue of 908 million USD/y, which can be utilized to import ethylene. For the susta... [more]
3314. LAPSE:2023.1657
A Novel Multi-Sensor Data-Driven Approach to Source Term Estimation of Hazardous Gas Leakages in the Chemical Industry
February 21, 2023 (v1)
Subject: Environment
Keywords: independent hazardous-gas-leakage scenarios (IHGLSs), multi-sensor data-driven, real-time experimental observations and implementation, source term estimation, unsupervised multi-sensor data clustering and analysis
Source term estimation (STE) is crucial for understanding and addressing hazardous gas leakages in the chemical industry. Most existing methods basically use an atmospheric transport and dispersion (ATD) model to predict the concentrations of hazardous gas leakages from different possible sources, compare the predicted results with multi-sensor data, and use the deviations to search and derive information on the real sources of leakages. Although performing well in principle, complicated computations and the associated computer time often make these methods difficult to apply in real time. Recently, many machine learning methods have also been proposed for the purpose of STE. The idea is to build offline a machine-learning-based STE model using data generated with a high-fidelity ATD model and then apply the machine learning model to multi-sensor data to perform STE in real time. The key to the success of a machine-learning-based STE is that the machine-learning-based STE model has to... [more]
3315. LAPSE:2023.1651
Efficient Remediation of Cadmium Contamination in Soil by Functionalized Biochar: Recent Advances, Challenges, and Future Prospects
February 21, 2023 (v1)
Subject: Environment
Keywords: biochar, cadmium contamination, challenges and prospects, recent advances, soil remediation
Heavy metal pollution in soil seriously harms human health and animal and plant growth. Among them, cadmium pollution is one of the most serious issues. As a promising remediation material for cadmium pollution in soil, functionalized biochar has attracted wide attention in the last decade. This paper summarizes the preparation technology of biochar, the existing forms of heavy metals in soil, the remediation mechanism of biochar for remediating cadmium contamination in soil, and the factors affecting the remediation process, and discusses the latest research advances of functionalized biochar for remediating cadmium contamination in soil. Finally, the challenges encountered by the implementation of biochar for remediating Cd contamination in soil are summarized, and the prospects in this field are highlighted for its expected industrial large-scale implementation.
3316. LAPSE:2023.1648
Migration Behavior and Influencing Factors of Petroleum Hydrocarbon Phenanthrene in Soil around Typical Oilfields of China
February 21, 2023 (v1)
Subject: Environment
Keywords: penetration curve, petroleum pollution, PHE, soil column, typical oilfields, vertical migration
Petroleum spills and land contamination are becoming increasingly common around the world. Polycyclic aromatic hydrocarbons (PAHs) and other pollutants found in petroleum are constantly migrating underground, making their migration in soil a hot research topic. Therefore, it is of great significance to evaluate the migratory process of petroleum hydrocarbons in petroleum-polluted soil to clarify its ecological and environmental risks. In this study, Phenanthrene (PHE) was used as a typical pollutant of PAHs. The soil was gathered from three typical oilfields in China, and a soil column apparatus was built to simulate the vertical migration of PHE in the soil. The migration law and penetration effect of PHE in various environmental conditions of soil were investigated by varying the ionic strength (IS), pH, particle size, and type of soil. According to the literature, pH has no discernible effect on the migration of PHE. The migration of PHE was adversely and positively linked with chan... [more]
3317. LAPSE:2023.1643
Special Issue “Optimization Technology of Greenhouse Gas Emission Reduction”
February 21, 2023 (v1)
Subject: Environment
The problem of global warming and its relationship with human activity is increasingly evident [...]
3318. LAPSE:2023.1639
Reptile Search Algorithm (RSA)-Based Selective Harmonic Elimination Technique in Packed E-Cell (PEC-9) Inverter
February 21, 2023 (v1)
Subject: Environment
Keywords: multilevel inverter, nine–level Packed E–Cell (PEC–9), reptile search algorithm, selective harmonic elimination
The multilevel inverters (MLIs) are capable of handling large quantities of power and generating high-quality output voltages. Consequently, the size of the filters is reduced, and the circuitry is simplified. As a result, they have a diverse range of uses in the industrial sector, especially in smart grids. The input voltage boosting feature is required to utilize the MLI with renewable energy. In addition, a large number of components are required to attain higher output voltage levels, which increases the cost of the circuit and weight. A variety of MLI topologies have been identified to reduce losses, device quantity, and device ratings. The selective harmonic elimination (SHE) approaches reduce distinct lower order harmonics by computing the ideal switching angles. This research presents a nine−level Packed E−Cell (PEC−9) inverter that uses selective harmonic elimination to eliminate total harmonic distortion. In order to calculate the best switching angle, the reptile search algo... [more]
3319. LAPSE:2023.1617
A Review on Pyrometallurgical Extraction of Antimony from Primary Resources: Current Practices and Evolving Processes
February 21, 2023 (v1)
Subject: Environment
Keywords: antimony, critical metals, extractive metallurgy, Refining, technology selection
Antimony is classified as a critical/strategic metal. Its primary production is predominated by China via pyrometallurgical routes such as volatilization roasting—reduction smelting or direct reduction smelting. The performance of most of the pyro-processes is very sensitive to concentrate type and grade. Therefore, technology selection for a greenfield plant is a significant and delicate task to maximize the recovery rate of antimony and subsequently precious metals (PMs), mainly gold, from the concentrates. The current paper reviews the conventional pyrometallurgical processes and technologies that have been practiced for the treatment of antimony concentrates. The blast furnace is the most commonly used technology, mainly because of its adaptability to different feeds and grades and a high recovery rate. In addition, several other more environmentally friendly pyrometallurgical routes, that were recently developed, are reviewed but these are still at laboratory- or pilot-scales. For... [more]
3320. LAPSE:2023.1615
Effect of Fulvic Acid in Landfill Leachate Membrane Concentrate on Evaporation Process
February 21, 2023 (v1)
Subject: Environment
Keywords: boiling point, evaporation, fulvic acid, landfill leachate membrane concentrate, softening, viscosity
Landfill leachate membrane concentrate (LLMC) poses risks to the environment and is commonly treated by evaporation. As the main component of the dissolved organic matter in LLMC, fulvic acid (FA) was selected as a representative to investigate its effect on evaporation and the removal efficiency by pretreatment in this study. According to the water quality indexes and three-dimensional fluorescence spectra of LLMC samples collected from five landfills in China, the concentration of total organic carbon in LLMC was 700−2500 mg·L−1, in which FA accounted for 50−85%. The boiling point and viscosity of the configured FA-NaCl-Na2SO4 solution both increased significantly when FA was concentrated 20 times (approximately 30,000 mg·L−1). Due to the presence of FA, the violent frothing phenomenon appeared at above 70 °C in evaporation, and the solubility of CaSO4·2H2O in FA-NaCl-Na2SO4 solution was significantly lower than that without FA. All these results indicated that the high FA concentrat... [more]
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