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SUSTAINABLE DELAMINATION OF CATHODE MATERIALS FROM SPENT LITHIUM-ION BATTERIESYi Ji (12448896) 25 April 2022 (has links)
<p>The predicted growth in demand for electric vehicles (EVs) has given rise to increasing use of lithium-ion batteries (LIBs), which are the source of energy used in all EVs. Recycling of spent LIBs not only can supply more materials to manufacturing new LIBs, but also can mitigate haz-ardous waste disposal in the environment. Direct recycling focuses on separating cathode materials to be re-purposed or remanufactured. Delamination of cathode materials is the necessary first step; however, it is fraught with difficulties due to the strong adhesive forces provided by the polyvi-nylidene fluoride (PVDF) binder that is widely used in LIBs. The widely accepted delamination methods are N-Methyl-2-pyrrolidone (NMP) solvent dissolution and direct calcination, which are not desirable due to either environmental and health concerns or high energy consumption.</p>
<p>The lithium chemical systems (LiCl, LiNO<sub>3</sub>, and LiOH) and their binary eutectic systems, were systematically studied to recover heterogeneous cathode active materials (NMC 111 and LMO) from spent LIBs of EVs. The LiOH-LiNO<sub>3</sub> eutectic system showed 98.3% peel-off effi-ciency under preferable conditions. The recycled products were characterized using ICP-OES, XPS, SEM, and XRD. There were minimal changes in chemical composition, morphology, or crystal structure of the recycled cathode materials after LiOH-LiNO3 eutectic treatment, compared with those recycled with an AlCl<sub>3</sub>-NaCl eutectic molten salt treatment that introduces more Al contamination and morphological defects. </p>
<p>In order to avoid corrosive chemicals and minimize particle agglomeration, additional lith-ium salts were investigated, including LiOAc (lithium acetate), Li<sub>2</sub>CO<sub>3</sub>, and Li<sub>2</sub>SO<sub>4</sub>. A peel-off efficiency of up to 98.5% was achieved at a LiOAc to LiNO<sub>3</sub> molar ratio of 3:2, salt to cathode mass ratio of 10:1, temperature of 300° C, and a holding time of 30 minutes. To validate the effect of the cations, the recycled products from the molten sodium salt system (NaOAc-NaNO3) were tested. The lithium salt system achieved separation at a lower temperature. Use of LiOAc-LiNO<sub>3</sub> minimized morphological changes compared with direct calcination.</p>
<p>The effective separation in LiOH-LiNO3 or LiOAc-LiNO3 molten salt systems was based on promotion of PVDF decomposition, and these two systems may be feasible for recycling other typical cathodes (LCO and LFP) where PVDF is used as the binder. Use of molten lithium salts as alternatives to direct calcination or use of other solvents, may help facilitate recycling of spent LIBs, and even achieve a way for closed loop direct recycling of materials.</p>
<p> Additionally, a chemical-free pressure washing system was studied to overcome the adhe-sion provided by PVDF. Although the pressure washing system was not able to remove PVDF from the cathode materials, nearly instant separation from the aluminum backing was achieved when the shear stress and normal stress provided by the impacting of high-pressure waterjet was stronger than the binding forces. Factors investigated included water pressure, distance between the nozzle and cathode, the incident angle of the water jet, and the nozzle type (sprayer angle). A 34-1 fractional factorial design was used to evaluate the parameters and find the optimal operating conditions. A small amount of Al and consistent morphology (of nearly pristine cathode active materials) were detected. Three kinds of recycled cathode materials (NMC&LMO, LCO, and LFP) were used as inputs to investigate a sulfuric acid leaching process, indicating high leaching effi-ciencies (lithium > 90% and cobalt > 85%).</p>
<p>The degradation of cathode active materials or PVDF affects the adhesion force between cathode materials layer and Al current collector. Because delamination replies on inactivation of bonding forces provided by PVDF, it is believed that the storage environment (air, O<sub>2</sub> or H<sub><strong>2</strong></sub>O) will affect the performances of delamination to some extent. Three representative methods (direct cal-cination, solvent extraction, and pressure washing system) of delamination were selected to eluci-date the effect from air exposure time. Direct calcination was barely influenced and stably sepa-rated CAMs in terms of peel-off efficiency. The pressure washing system or solvent extraction exhibited high peel-off efficiency using control samples, but the performance regarding either Al contamination or separation efficiency significantly worsened after long air exposure time. This hypothesis could explain lack of reproducibility of some results in different studies and highlight the importance of strict storage condition of spent LIBs to direct recycling technology. </p>
<p>Overall, this thesis examines innovative delamination methods for the development of cost-efficient and environmentally friendly direct recycling of spent LIBs. Application of the eutectic molten lithium salt system (LiOH-LiNO<sub>3</sub> and LiOAc-LiNO<sub>3</sub>) or pressure washing system indicates promising benefits to reduce toxic gas emission and energy consumption, and accelerate the cir-cular economy.</p>
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Operational Strategies and Optimal Policies for the Diffusion of Environmental Energy Systems / Stratégies opérationnelles et politiques optimales pour la diffusion des systèmes énergétiques de l'environnementGoodarzi, Shadi 19 April 2016 (has links)
L’objectif principal de cette thèse est d’étudier d’abord les problèmes potentiels qui peuvent entraver ou accélérer la diffusion des systèmes énergétiques environnementaux (par exemple, énergies renouvelables), puis l’impact de la pénétration de ces technologies dans le marché de l’énergie sur les équilibres du marché. À cette fin, nous observons le processus de diffusion à partir de différents points de vue tels que les décideurs, les fabricants, les clients et l’opérateur d’un système de transmission. Le premier chapitre de cette thèse fournit introduction et le contexte de la recherche. Le deuxième chapitre examine le rôle des décideurs et des fabricants technologiques sur la diffusion de ces technologies, alors que le troisième chapitre est consacré à l’étude de l’impact des différentes dimensions d’information sur la décision d’adopter une technologie environnementale tout au long du processus de telle adoption. Le chapitre quatre examine l’effet de l’entrée de ces technologies (énergies renouvelables) dans le marché d’électricité sur le prix au comptant d’électricité et sur le déséquilibre offre-demande. Enfin, le chapitre cinq conclut les résultats de cette étude et fournit des orientations pour des recherches futures. Les résultats présentés dans cette thèse offrent un aperçu de gestion précieux pour les décideurs, les fabricants de technologie et aux entreprises opérant dans le secteur de l'énergie. / The main goal of this dissertation is to study the potential factors that may hamper or accelerate the diffusion of environmental energy systems (e.g: renewable energies). To this end, using different methods such as game theory, survey data analysis, and time series data analysis we observe the diffusion of these technologies from different perspectives such as policy makers, manufacturers, and customers. This dissertation consists of five chapters. The first chapter provides introduction and background of the research. Second chapter investigates the role of policy makers and technology manufacturers on the diffusion of the environmental energy systems. Chapter three is dedicated to studying the impact of different information dimensions on the different stages of environmental technology adoption process. Chapter four examines effect of the penetration of the environmental energy systems into the electricity market by studying the electricity spot price and electricity supply- demand imbalance. Lastly, chapter five concludes the results of this study and provides directions for future researches. The results reported in this dissertation offer valuable managerial insights to policy makers, technology manufacturers and to firms operating in the energy sector.
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Chemodynamics of heavy metal in the rhizosphere: implications to phytoremediation of metal contaminated soilsKim, Kwon-Rae January 2007 (has links)
The influence of hyperaccumulator and phytostabilizing plants on soil solution chemistry and subsequent metal dynamics in the rhizosphere was investigated to gain a better understanding of the mechanisms governing metal availability and plant uptake at the soil:root interface during phytoremediation of metal contaminated soils.
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Geographical information systems and natural resource management in Zambia : a dissertation presented in partial fulfilment of the requirements for a Masters degree in Environmental Management at Massey University, Palmerston North, New ZealandMwape, Ackim January 2010 (has links)
Natural resources play a critical role in the welfare of developing countries. In Zambia, even though its vast natural resources have been important to its economy as well as its people, their exploitation has resulted in severe land and environmental degradation in most parts of the country. Reliable information as to the exact extent and degree of natural resources problems is critically lacking. For effective control and management of these natural resources problems, timely, up‐to‐date, accurate and complete spatial data are needed. The integrated application of Geographical Information Systems (GIS) and remote sensing to model natural resources management data, especially at regional level, is presented in this dissertation. Three case studies in Zambia are presented and free, internet‐based, datasets are used to demonstrate the application of GIS to support natural resource management decisions in Zambia. The results of the case studies show that while data‐gathering obstacles remain in the use of GIS in Zambia, the systems can be used successfully to fill gaps in decision‐making in natural resources management. The results of the case studies have been used to make recommendations as a way forward for the use of GIS and remote sensing data in natural resource management in Zambia. Finally, selected technical issues associated with data access, data incompatibility and data accuracy are identified as important areas of future research.
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Development and application of ultrasound technology for treatment of organic pollutantsThangavadivel, Kandasamy January 2010 (has links)
The necessity of cost effective, environmentally friendly technology has become increasingly important to remediate persistent organic pollutants in the environment. The emerging greener ultrasound technology has the potential to serve the remediation industry. In this study, the use of low power, high frequency (HF) ultrasound (1.6 MHz, 145 W/L) has been shown to effectively remediate DDT (90% of 8 mg/L) in water and sand slurries. Addition of iron powder accelerated DDT degradation in the sand slurry under ultrasonication. The potential of HF ultrasound (1.6 MHz, 160 W/L) in degradation of the non-volatile, polar model compound methylene blue (MB) was studied in MB spiked demineralised water and wastewater. A 70 % of 0.4 mg/L of MB was degraded in demineralised water whereas only 54% of MB degraded in MB spiked wastewater. There was a decrease in MB degradation rate with an increase in MB concentration. High power, low frequency (LF) ultrasound (20 kHz, 932 W/L) was used to desorb 400 mg/L of DDT added to three different natural soil slurries at 5, 10, 15 and 20 wt. % each. Each soil slurry was prepared in 0.1% v/v SDS surfactant solution, soaked for 30 min. and heated for another 30 min. at 40 oC before sonication. For the neutral pH soil slurry with higher dissolved organic carbon, the desorption efficiency achieved was over 80% in 30 s sonication. Alkaline soil with higher surface area than neutral soil indicated 60% desorption efficiency while the acidic soil, with the highest surface area and a higher amount of non-soluble organic matter, yielded 30% desorption efficiency under similar desorption conditions. Coconut fibre, used to biosorb the desorbed DDT in the decanted solution, was found to have over 25 g/kg of biosorption capacity for DDT. The surfactant SDS and associated DDT were completely separated from decanted liquid of the desorbed slurry with alum using adsorptive micellar flocculation in 60 min. settling. Acidic pH and molar concentration ratio of Al3+/SDS = 0.5 was used to completely remove the DDT. Using 20 kHz, 1125 W/L of sonication in an 80 mL reactor with air saturated 50 mg/L DDT at 20oC, the DDT removal efficiency achieved was 80% in 20 min. With zero valent iron addition, DDT removal efficiency in 15 min. is 100% with 15 and 22 mg/L of initial DDT concentrations. The settled DDT slurrywas remediated using 20 kHz at 240 W/L achieving DDT removal efficiency of 87% in 15 min. Also LF ultrasound was found to be effective in remediating chloroform (8 mg/L in 60 min) from spiked demineralised water and contaminated groundwater in both batch (120 W/L) and flow cell (6000 W/L) modes. Modeling and simulation of the ultrasonic reactor under 20 kHz ultrasonication was performed for various shape reactors using commercially available software. For almost all reactors, the highest ultrasonic intensity was observed near the transducer???s vibrating area. It was found that the highest acoustic pressure distribution, which is critical to the performance of the reactor, occurred in the conical reactor and flow cell configuration. / Thesis (PhD)--University of South Australia, 2010
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Non-Financial Returns of Enterprise-Led Development Assistance - A Study of Energy-Related EnterprisesKolominskas, Chaim Unknown Date (has links)
The Rural Energy Enterprise Development (REED) initiative provides assistance to energy-related enterprises to prepare them for growth and to make eventual investments by mainstream financial partners less risky. This study assesses the non-financial returns of a number of REED-type enterprises and provides guidance for the selection and ongoing evaluation of these enterprises within the context of development interventions. This study concludes that desired development outcomes should provide the basis for programme objectives against which non-financial returns can be measured. However, qualitative information is also necessary, as the context within which an enterprise operates largely defines the importance of these returns. Further work to improve the understanding of this context is necessary prior to the development of a formalised monitoring programme. Limitations of the assessment process should be recorded and addressed through the ongoing review of the programme, other monitoring efforts and further research.
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Development and application of ultrasound technology for treatment of organic pollutantsThangavadivel, Kandasamy January 2010 (has links)
The necessity of cost effective, environmentally friendly technology has become increasingly important to remediate persistent organic pollutants in the environment. The emerging greener ultrasound technology has the potential to serve the remediation industry. In this study, the use of low power, high frequency (HF) ultrasound (1.6 MHz, 145 W/L) has been shown to effectively remediate DDT (90% of 8 mg/L) in water and sand slurries. Addition of iron powder accelerated DDT degradation in the sand slurry under ultrasonication. The potential of HF ultrasound (1.6 MHz, 160 W/L) in degradation of the non-volatile, polar model compound methylene blue (MB) was studied in MB spiked demineralised water and wastewater. A 70 % of 0.4 mg/L of MB was degraded in demineralised water whereas only 54% of MB degraded in MB spiked wastewater. There was a decrease in MB degradation rate with an increase in MB concentration. High power, low frequency (LF) ultrasound (20 kHz, 932 W/L) was used to desorb 400 mg/L of DDT added to three different natural soil slurries at 5, 10, 15 and 20 wt. % each. Each soil slurry was prepared in 0.1% v/v SDS surfactant solution, soaked for 30 min. and heated for another 30 min. at 40 oC before sonication. For the neutral pH soil slurry with higher dissolved organic carbon, the desorption efficiency achieved was over 80% in 30 s sonication. Alkaline soil with higher surface area than neutral soil indicated 60% desorption efficiency while the acidic soil, with the highest surface area and a higher amount of non-soluble organic matter, yielded 30% desorption efficiency under similar desorption conditions. Coconut fibre, used to biosorb the desorbed DDT in the decanted solution, was found to have over 25 g/kg of biosorption capacity for DDT. The surfactant SDS and associated DDT were completely separated from decanted liquid of the desorbed slurry with alum using adsorptive micellar flocculation in 60 min. settling. Acidic pH and molar concentration ratio of Al3+/SDS = 0.5 was used to completely remove the DDT. Using 20 kHz, 1125 W/L of sonication in an 80 mL reactor with air saturated 50 mg/L DDT at 20oC, the DDT removal efficiency achieved was 80% in 20 min. With zero valent iron addition, DDT removal efficiency in 15 min. is 100% with 15 and 22 mg/L of initial DDT concentrations. The settled DDT slurrywas remediated using 20 kHz at 240 W/L achieving DDT removal efficiency of 87% in 15 min. Also LF ultrasound was found to be effective in remediating chloroform (8 mg/L in 60 min) from spiked demineralised water and contaminated groundwater in both batch (120 W/L) and flow cell (6000 W/L) modes. Modeling and simulation of the ultrasonic reactor under 20 kHz ultrasonication was performed for various shape reactors using commercially available software. For almost all reactors, the highest ultrasonic intensity was observed near the transducer???s vibrating area. It was found that the highest acoustic pressure distribution, which is critical to the performance of the reactor, occurred in the conical reactor and flow cell configuration. / Thesis (PhD)--University of South Australia, 2010
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Non-Financial Returns of Enterprise-Led Development Assistance - A Study of Energy-Related EnterprisesKolominskas, Chaim Unknown Date (has links)
The Rural Energy Enterprise Development (REED) initiative provides assistance to energy-related enterprises to prepare them for growth and to make eventual investments by mainstream financial partners less risky. This study assesses the non-financial returns of a number of REED-type enterprises and provides guidance for the selection and ongoing evaluation of these enterprises within the context of development interventions. This study concludes that desired development outcomes should provide the basis for programme objectives against which non-financial returns can be measured. However, qualitative information is also necessary, as the context within which an enterprise operates largely defines the importance of these returns. Further work to improve the understanding of this context is necessary prior to the development of a formalised monitoring programme. Limitations of the assessment process should be recorded and addressed through the ongoing review of the programme, other monitoring efforts and further research.
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Development and application of ultrasound technology for treatment of organic pollutantsThangavadivel, Kandasamy January 2010 (has links)
The necessity of cost effective, environmentally friendly technology has become increasingly important to remediate persistent organic pollutants in the environment. The emerging greener ultrasound technology has the potential to serve the remediation industry. In this study, the use of low power, high frequency (HF) ultrasound (1.6 MHz, 145 W/L) has been shown to effectively remediate DDT (90% of 8 mg/L) in water and sand slurries. Addition of iron powder accelerated DDT degradation in the sand slurry under ultrasonication. The potential of HF ultrasound (1.6 MHz, 160 W/L) in degradation of the non-volatile, polar model compound methylene blue (MB) was studied in MB spiked demineralised water and wastewater. A 70 % of 0.4 mg/L of MB was degraded in demineralised water whereas only 54% of MB degraded in MB spiked wastewater. There was a decrease in MB degradation rate with an increase in MB concentration. High power, low frequency (LF) ultrasound (20 kHz, 932 W/L) was used to desorb 400 mg/L of DDT added to three different natural soil slurries at 5, 10, 15 and 20 wt. % each. Each soil slurry was prepared in 0.1% v/v SDS surfactant solution, soaked for 30 min. and heated for another 30 min. at 40 oC before sonication. For the neutral pH soil slurry with higher dissolved organic carbon, the desorption efficiency achieved was over 80% in 30 s sonication. Alkaline soil with higher surface area than neutral soil indicated 60% desorption efficiency while the acidic soil, with the highest surface area and a higher amount of non-soluble organic matter, yielded 30% desorption efficiency under similar desorption conditions. Coconut fibre, used to biosorb the desorbed DDT in the decanted solution, was found to have over 25 g/kg of biosorption capacity for DDT. The surfactant SDS and associated DDT were completely separated from decanted liquid of the desorbed slurry with alum using adsorptive micellar flocculation in 60 min. settling. Acidic pH and molar concentration ratio of Al3+/SDS = 0.5 was used to completely remove the DDT. Using 20 kHz, 1125 W/L of sonication in an 80 mL reactor with air saturated 50 mg/L DDT at 20oC, the DDT removal efficiency achieved was 80% in 20 min. With zero valent iron addition, DDT removal efficiency in 15 min. is 100% with 15 and 22 mg/L of initial DDT concentrations. The settled DDT slurrywas remediated using 20 kHz at 240 W/L achieving DDT removal efficiency of 87% in 15 min. Also LF ultrasound was found to be effective in remediating chloroform (8 mg/L in 60 min) from spiked demineralised water and contaminated groundwater in both batch (120 W/L) and flow cell (6000 W/L) modes. Modeling and simulation of the ultrasonic reactor under 20 kHz ultrasonication was performed for various shape reactors using commercially available software. For almost all reactors, the highest ultrasonic intensity was observed near the transducer???s vibrating area. It was found that the highest acoustic pressure distribution, which is critical to the performance of the reactor, occurred in the conical reactor and flow cell configuration. / Thesis (PhD)--University of South Australia, 2010
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Técnicas de permacultura como tecnologias socioambientais para a melhoria na qualidade da vida em comunidades da Paraíba / Permaculture Techniques as Social and Environmental Technologies to improve the life quality in communitiesPaes, Wellington Marchi 29 April 2014 (has links)
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Previous issue date: 2014-04-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Permaculture techniques are alternatives that have been developed in order to produce a permanent crop that restores the human being to the environment, taking into account the observation of the natural environment and experimentation, with the intent of improving the various factors that are contributing to the deterioration of life and nature. Thus, it seeks to restore the nature balance s that human actions have broken. The lack of sanitation has brought many negative consequences, both to human health and the environment, so the waste managing, whether solid or liquid, should be among all local governments priorities. Because the investment in peri-urban areas is inferior to the urban ones, actions focused on eliminating the diffused pollution sources like inappropriate domestic waste disposal and its impact are essential. Therefore, this study intended to demonstrate among local communities that cultivation and the solid and liquid wastes could be sustainably combined. Permaculture activities were carried out: in a familiar way with children from the Escola Elementar Nova Vida, in Pitimbu Municipality-PB; solid waste was reused in handmade artifact in the maroon community of Ipiranga, in the Gurugi district, Conde, PB; and deployment of ecological tanks, with banana circles, for the treatment of greywater, in Engenho Velho, and the evapotranspiration tanks (green tanks for blackwater treatment) in the Condomínio Amizade in João Pessoa, PB. Motivating the communities to develop the proposed activities was a challenge, and only a few people participated. However, after the implementation of the activities there was a general feeling of satisfaction among the participants. The goal of this project was the adoption of Environmental Social technics by specific communities that would later on work as models to be copied by other communities. We have achieved the purpose of the project as we noticed that not only the methodologies have improved the communities where they were implemented, but also that those were spread and adopted by other communities, showing the appropriation of these technologies by the people of these communities. / Técnicas permaculturais são alternativas que vêm sendo desenvolvidas, no intuito de produzir uma cultura permanente que reintegra o ser humano ao ambiente, levando em consideração a observação do meio natural e a experimentação no sentido de aprimorar os diversos fatores que estão auxiliando a degradar a vida e a natureza. Dessa forma, busca restituir o equilíbrio natural que as ações humanas têm quebrado. A falta de saneamento básico tem trazido muitas consequências negativas, tanto à saúde humana quanto ao ambiente, deste modo, gerenciar os resíduos gerados, sejam sólidos ou líquidos deveria estar entre as prioridades dos governos municipais. Como em regiões periurbanas há menos investimento nesta área que nos centros urbanos, ações que diminuam os impactos dos resíduos, no sentido de eliminar as fontes de poluição difusa, como a destinação inadequada do lixo e dos esgotos domésticos são essenciais. Assim, este trabalho visou realizar ações demonstrativas em comunidades da Paraíba, de como os resíduos sólidos, os líquidos e a plantação podem ser integrados de forma sustentável. Foram desenvolvidas atividades de Permacultura, com o plantio de hortas agroecológicas, junto aos alunos da Escola Municipal de Ensino Fundamental de Nova Vida, no Assentamento Nova Vida em Pitimbu; de reuso de resíduos sólidos à produção artística na comunidade quilombola de Ipiranga, no distrito de Gurugi em Conde; e a implantação de fossas ecológicas com a construção de Círculos de Bananeiras no Vale do Gramame, para o tratamento de águas cinzas, e do Tanque de Evapotranspiração no Condomínio Amizade, para o tratamento de águas negras, em João Pessoa. Deparou-se com a dificuldade de articulação comunitária nos locais e apenas poucas pessoas participaram das atividades propostas. No entanto, após as ações desenvolvidas, verificou-se a satisfação de todos os que participaram destas. Como o objetivo deste trabalho foi a implementação de algumas Tecnologias Socioambientais nas comunidades, para servir de modelo para a sua replicação por outros comunitários, pode-se dizer que para além dos resultados positivos da implantação das tecnologias por si, visto que melhorou bastante as áreas em que foram aplicadas, pela eliminação de esgotos a céu aberto, houve a disseminação das técnicas permaculturais que já foram reaplicadas em outros locais, o que demonstra a apropriação destas metodologias pelas pessoas das comunidades.
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