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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Co-Pyrolysis of Fruit Waste and High Density Polyethylene: Effect of Composition, Temperature and CO2 Environment on Pyrolysis Products

Nooh, Abdullah 06 1900 (has links)
Waste recycling is gaining prominence and acceptance compared to landfilling to reduce greenhouse gas emissions. Municipal solid waste (MSW), the largest source of solid waste, is primarily composed of food waste, plastics packaging and papers. Thermochemical recycling technique, such as pyrolysis, is considered as a promising alternative for producing value-added products. Pyrolysis is a process occurring in inert environments at moderate temperatures controlled by parameters such as the reaction temperature, heating rate and residence time to produce bio-oil and biochar. It is also known for its high tolerance for mixed waste stream. In this thesis, fruit waste (FW) consisted of bananas, apples, oranges and cucumbers peels and commercial high density polyethylene (HDPE) as co-pyrolysis feedstock were investigated. Co-pyrolysis experiments were performed in a tubular furnace reactor to investigate the effect of polymer composition, temperature and CO2 atmosphere. HDPE composition was varied between 33–67% to investigate the effect of feedstock composition at 500 ˚C. A composition was fixed and then effect of temperature was assessed in the range 500–700 ˚C. Finally, in CO2 atmosphere, co-pyrolysis experiments were performed with 50% HDPE at 600 ˚C. The collected bio-oil and biochar were thoroughly characterized via different analytical techniques. The effect of different process parameters on bio-oil was studied by gas chromatography-mass spectrometry (GC/MS), proton nuclear magnetic resonance (1H NMR) and Fourier-transform ion cyclotron resonance mass spectroscopy (FT-ICR MS). Biochar samples are analyzed using scanning electron microscopy (SEM), CHNS elemental analysis and Fourier-transform infrared (FTIR). Detailed product composition revealed that formation of hydrocarbons was promoted with increasing HDPE, while significant deoxygenation was observed with increased temperature. In addition, heavier molecules in the bio-oil were studied via FT-ICR MS. HDPE loading and CO2 atmosphere stabilized the biochar by reducing the oxygen content. The results demonstrated the potential use of HDPE as a co-feed with FW in a pyrolysis system to produce valuable products.
2

Masters_TJS.pdf

Trevor J Shoaf (8588478) 08 December 2022 (has links)
<p>Biodegradation of untreated cotton, linen, and hemp textiles as three substrates – measured through biogas production – was studied to compare digestion yield and the ability of anaerobic sludge as inoculum to utilize the sugars in these textiles without pretreatment. Digestion of these textile substrates was carried out over a 26-day study, with daily sampling of biogas production, to measure biogas production rate and accumulation. The flasks were maintained at 37 °C and 150 RPM with a substrate to inoculum ratio (SIR) of 0.5 g sugars from substrate g-1 VSinoculum from anaerobic sludge. Biogas samples were analyzed through gas chromatography (GC) to determine general biogas composition produced by each textile. Biogas production was notable after the four-day mark; with first peaks occurring on day five (hemp, cellulose), day seven (cotton), and day nine (linen). Production of biogas in the control largely outperformed trials with no added substrate, but overall the methane fractions of the gas was lower than expected, indicating that pretreatment is likely necessary for more complete biodegradation of natural textiles. </p>
3

Solid waste management based on cost-benefit analysis using the WAMED model

Mutavchi, Viacheslav January 2012 (has links)
Efficient waste management enables the protection of human health, reducing environmental pollution, saving of natural resources, and achieving sustainable and profitable management of energy. In many countries, the general guidelines for waste management are set by national or local waste management plans. Various models provide local authorities with decision-making tools in planning long-term waste management scenarios.This study aims at providing a special model framework for the evaluation of ecological–economic efficiency (ECO-EE) of waste management. This will serve as an information support tool for decision making by actors of a solid waste management (SWM) scheme, primarily at the municipal and regional levels. The objective of this study is to apply the waste management’s efficient decision (WAMED) model along with the company statistical business tool for environmental recovery indicator (COSTBUSTER) model to SWM and municipal solid waste (MSW) schemes in general in order to evaluate and improve their ECO-EE. COSTBUSTER is a mathematical indicator for the size and extent of implementation costs of a certain SWM scheme, compared with the total size of the average financial budget of a SWM actor of a certain kind. In particular, WAMED is proposed for evaluating the suitability to invest in baling technology. Baling of solid waste is an emerging technology which is extensively used worldwide to temporarily store waste for either incineration or recovery of raw materials. The model for efficient use of resources for optimal production economy (the EUROPE model) is for the first time applied to emissions from baling facilities. It has been analysed how cost-benefit analysis (CBA) and full cost accounting (FCA) can facilitate environmental optimisation of SWM schemes. The effort in this work represents a continuation of such ambitions as an enlargement of the research area of CBA based modelling within SWM. In the thesis, certain theoretical and economic aspects of SWM were analysed as case studies. A shift of viewpoints within the field of waste management is presented. This shift is in accordance with the prevailing concept of sustainable development, as commonly understood. It is concluded that in the practical SWM context, the findings of the study point at the possibilities to modify the common CBA- and FCA-based methods by WAMED, COSTBUSTER, and EUROPE. Therefore, it can be said that estimations in a SWM scheme can be carried out by using certain economic model, if properly modified in a logical and plausible way. New principles for cost allocation to SWM residual products are presented in the current work. They imply strong industrial cost saving incentives through promoting the introduction of new and improved processing technologies for rest-waste. Such incentives then strongly promote investments that are likely to improve both the environment and the corporate profitability. Thereby, the occurrence of non-commercialised, and hence not utilized, wastes is reduced. This improves the short term corporate economy through saving raw materials such as solid waste fuel, spending less time for administrating waste flows, and less wear and tear of the plant machinery. Additional environmental advantages which affect the balance sheets in a favourable way are related to the long-term business economy and extended environmental goodwill. This is due to the recently introduced way of considering solid waste as regular goods in financial terms - the equality principle. If waste is seen as goods, and not wasted in landfills, the environment will improve. This, in turn, leads to an improved quality of life. Based on the current study, it is recommended to apply WAMED to SWM schemes in order to evaluate their ECO–EE to justify decision making and investments. Also, it is recommended to apply COSTBUSTER, based on the current WAMED outcome, to SWM schemes to determine their relative size and extent. It is recommended to apply EUROPE to the emissions in case of accidental burning, treatment of leachate, andabatement with odours at any SWM scheme, based on the induced economic incentives, in order to reduce unwanted substances and phenomena.
4

Sustentabilidade e desenvolvimento regional: uma análise do potencial econômico dos resíduos sólidos urbanos no Oeste do Paraná 1970 - 2020 / Sustainability and regional development: an analysis of the economic potential of urban solid waste in West of Paraná - 1970 - 2020

Bianco, Tatiani Sobrinho Del 13 March 2014 (has links)
Made available in DSpace on 2017-07-10T18:33:14Z (GMT). No. of bitstreams: 1 Tatiani Sobrinho Del Bianco.pdf: 3941335 bytes, checksum: 389260f4ef8c218c8f73202bf660d0fc (MD5) Previous issue date: 2014-03-13 / The various activities inserted in the production processes are characterized by the generation of common solids (MSW) waste, whether in solid, liquid or gaseous. Therefore, this study aims to identify factors capable of explaining the economic potential of MSW as a sustainable regional development factor, transforming the problem of MSW generation in new business opportunity. For this purpose, the methodology included the implementation of steps to characterize the source of MSW municipalities under study, analysis of the models and technologies used in MSW, and identification of potential bottlenecks in the economic sectors and the systematization of results by presenting a new economic model using MSW as inputs in production processes. The results showed that the municipalities under study had an average generation of 54.5 t / day of plastic; 12 t / day of glass; 6:06 l t / day of metal; 60.6 tons / day of paper; 5.5 ton / day from other waste types and 418.5 tons / day of organic. It was identified that the marketing of MSW aluminum, cardboard and PET is more expressive in the states of São Paulo, Minas Gerais and Paraná. From this information it was possible to estimate the total gross revenue for the 30 municipalities in the study, which was approximately R$ 3,642,408.38, of which this was more notable in the municipalities of Cascavel, Foz do Iguacu and Toledo , which together were responsible for obtaining 57% of the total gross revenue for the cities analyzed. The systematization of the results showed that the new model of MSW, send about 5.6 tonnes/day of MSW to the municipal landfill of Toledo, representing a reduction of 92% of the total previously forwarded by using the traditional management model MSW. Thus, the development of this new management model would help the sustainable development of meso study, it would be able to generate income from the implementation of new models of factories, developing new technologies, increased service life and reduced need for increased of area landfills and thus will make the municipalities fall under the guidelines of the law 12.305/2010 PNRS. / As diversas atividades inseridas nos processos produtivos têm como característica comum à geração de resíduos sólidos urbanos (RSU), sejam eles sólidos, líquidos ou gasosos. Diante disso, esse trabalho visa identificar elementos capazes de explicitar o potencial econômico dos RSU como fator de desenvolvimento regional sustentável, transformando a problemática da geração de RSU em oportunidade de novos negócios. Para tanto, a metodologia contemplou a execução de etapas de caracterização da fonte geradora de RSU dos municípios em estudo, análise dos modelos e tecnologias utilizadas na gestão dos RSU, identificação das potencialidades e gargalos nos setores econômicos e a sistematização dos resultados por meio da apresentação de um novo modelo econômico utilizando o RSU como insumos dos processos produtivos. Os resultados demonstraram que os municípios em estudo, apresentaram uma geração média de 54.5 t/dia de plástico; 12 t/dia de vidro; l 6.06 t/dia de metal; 60.6 t/dia de papel; 5.5 t/ dia de outros tipos de resíduos e, 418.5 t/dia de orgânicos. Identificou-se que a comercialização dos RSU de alumínio, papelão e PET é mais expressiva nos estados de São Paulo, Minas Gerais e Paraná. A partir dessas informações foi possível estimar a receita bruta total para os 30 municípios em estudo, que foi de cerca de R$3.642.408,38, dentre os quais esta foi mais expressiva nos municípios de Cascavel, Foz do Iguaçu e Toledo, que juntos foram responsáveis pela obtenção de 57% da receita bruta total nos municípios analisados. A sistematização dos resultados demonstrou que o novo modelo de gestão dos RSU, enviaria cerca de 5.6 t/dia de RSU para o aterro sanitário municipal de Toledo, representando uma redução de 92% do total anteriormente encaminhado por meio da utilização do modelo tradicional de gestão dos RSU. Assim, o desenvolvimento desse novo modelo de gestão auxiliaria no desenvolvimento sustentável da mesorregião em estudo, pois seria capaz de gerar renda, a partir da implementação dos novos modelos de fábricas, desenvolvimento de novas tecnologias, aumento da vida útil e redução da necessidade de aumento de área para aterros sanitários e, assim, fará com que os municípios fiquem em conformidade com as diretrizes da lei de 12.305/2010 do PNRS.

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