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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.
71

Bilance provozu energetického využití odpadu / Ballance of waste to energy process

Hejl, Matěj January 2011 (has links)
This diploma thesis considers different attitudes to evaluation of lower heating value of municipal solid waste as a main parameter of calculation of effectiveness incineration process. Modification of general relation is done to calculate lower heating value by using methodology BREF/BAT for real plant. The next step is evaluation of lower heating value within measured data. Following part of this thesis is focused on establishing thermal efficiency of incineration boiler by using direct, indirect and “modified” indirect methods and statistical analyses of them. Analysis of important quantities, which enters the calculation of thermal efficiency, is realized. The establishment of measurement error in measuring these main parameters is done as well.
72

Modelování svozu komunálního odpadu s využitím GIS / Modelling of solid waste treatment with GIS

Jiřičková, Kateřina January 2010 (has links)
Under the current waste legislation in both European Union and Czech Republic, material recovery is preferred over other types of municipal solid waste treatment. However, waste collection systems have negative environmental impacts. This thesis deals with modeling and optimization of waste collection routes, which should lower their impact. The model makes use of the ArcGIS software system and operations research to optimize routes. Inputs of the model are the amount of waste produced in the region, locations of the final facilities, and their capacities. The amount of waste produced per district was estimated to be the portion of total waste produced corresponding to the number of inhabitants of given district. Final facilities are the assorting lines. Distances between districts and final facilities were computed by Network Analyst Extension of ArcGIS. The index method assigns the assorting lines to districts in a way that minimizes total distance traveled by waste collection vehicles, while respecting the capacity of the assorting lines. Outputs are waste collection routes and the distance, per waste type, traveled by the waste collection vehicles. The model allows changing the input data to observe changes in the waste collection system. The model was applied to the data from the capital of...
73

Urban Solid Waste Management in Mumbai Current challenges and future solutions for Urban Development : Minor Field Study

Joelsson, Yuri, Lord, Rebecca January 2016 (has links)
This study was conducted as a bachelor thesis at KTH Royal Institute of Technology in Stockholm in the spring of 2016. The study was carried out as a Minor Field Study (MFS) funded by the Swedish public authority Sida - Swedish International Development Cooperation Agency. The aim of the study is to provide an overview of the elements of the Municipal Solid Waste Management (MSWM) system in the city of Mumbai and Navi Mumbai, India. The main current challenges were identified and discussed with focus on social and political aspects such as waste management planning, strategies and legislations. The data for this research were gathered from literature studies and in-depth interviews with officer level stakeholders responsible for MSWM in Mumbai. The results show that the MSWM in Mumbai is facing many challenges and that there is a lack of coordination and a system approach on all levels. Further, a deeply rooted negative attitude towards the field of MSW could be observed. The main problems were shown to be related to politics and lack of awareness. The overall conclusion is that it is not enough that a small fraction of the society, with partially contradictory interests, is taking initiatives to improve the MSWM in Mumbai. In order to achieve a sustainable long-term solution, coordination and a more holistic system approach is necessary.
74

Municipal Organic Waste Composting as Management Option for Urban Agriculture: A case of Accra Metropolis, Ghana.

Hormenu, Michael Commander January 2011 (has links)
The ever-increasing population in the metropolis of Accra, Ghana resulting in con-cerns for finding lasting solutions to manage large volumes of waste produced can be tackled through composting for urban agriculture. With insanitary land filling serving as the major disposal option in the metropolis, plans to build the first ever sanitary landfill facility in the metropolis calls for measures to be taken in order to prolong the lifespan of the facility. This therefore necessitates the need to look into an alternative means of diverting organic waste from landfills. The objective of this research is to re-view the Municipal Solid Waste (MSW) management situations in Accra Metropolitan Assembly upon which an investigation is made into the various process steps involved in aerobic windrow composting and also finding out the possibility for integrating composting with urban agriculture. The study relied mainly on secondary data obtained from books, published articles, governmental documents, internet, and master thesis reports on related topics. By the help of a causal loop diagram, the interdependence of various policy actions and sys-tem elements in the waste management process are linked to illustrate the possibility of a composting programme for urban agriculture. Even though the metropolis for some time back has been operating a centralized composting facility, the facility is confirmed to be closed down due to problems ema-nating from financial inadequacy, power failure and mechanical breakdown. The study delve into the process steps in windrow composting and finally identified potentials for composting in the metropolis but however enumerated constraints ranging from human and environmental health, financial, institutional, policy directives, to public and leadership attitudes as stumbling blocks to the implementation of a centralized composting scheme. It finally concluded that the metropolis has the potentials to embark on composting for urban agriculture however, until measures are taken to overcome these constraints, implementing a centralized composting scheme in the metropolis may not be a sustainable option. It is further recommended that whiles the city authorities continue to tackle the constraints to pave way for the implementation of the program, efforts must be made in promoting small scale composting that rely on manually operated tools to help reduce organic waste loads in the municipal waste stream.
75

Evaluation of municipal solid waste illegal disposal in Masvingo City, Zimbabwe: towards a sustainable solid waste management model

Chireshe, Amato 11 1900 (has links)
Municipal solid waste management (MSWM) is a global problem as most local authorities fail to dispose MSW safely. In view of this, the study was aimed at evaluating environmental and health risks associated with municipal solid waste (MSW) illegal disposal as well as constraints faced by Masvingo City in MSWM, with a view to developing an alternative sustainable management model. The study, informed by the philosophy of pragmatism, employed a mixed methods design in which quantitative and qualitative data werecollected concurrently. Questionnaires comprising both close and open-ended questions, semi-structured interviews and site visits were used to collect data. The study population comprised participants from Masvingo City’s residential areas, Masvingo City Council employees, Environmental Management Agency (EMA) officials and informal waste pickers. A sample of 406 participants, comprising 354 residents from high-density, 16 residents from medium-density, 24 residents from low-density suburbs, six council employees, two EMA officials and four informal waste collectors participated in the survey. Concurrent triangulation was employed to analyse data. Basic numerical analysis was used for quantitative data while thematic data analysis was employed for qualitative data. Three main findings which emerged from the study were (a) Land pollution, air pollution, surface water pollution and loss of urban beauty, were the main environmental risks as at least 59 % of the respondents noted the four as environmental risks associated with illegal municipal solid waste disposal (b) Cholera, skin problems and malaria were the main health risks; and, (c) The main constraints related to MSW management were inadequate environmental education, lack of cooperation and participation from waste generatorsand lack of resources by Masvingo City . From the findings, 66 %, 52 % and 49 % of participants noted inadequate environmental education, lack of cooperation and participation, and lack of resources respectively as constraints faced by Masvingo City in MSWM. Basing on the findings of the study, it can be concluded that MSW disposal in Masvingo was a threat to the environment and human health and, as a result, a sustainable MSWM model was developed for Masvingo City. / Environmental Sciences
76

Comprehensive management model for solid waste collection and transportation in Peruvian urban municipalities

Bernal, Renato, Sánchez, Edgar, Mauricio, David, Raymundo, Carlos 01 January 2020 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Here in, comprehensive management model of municipal solid waste collection and transportation, “MIGRU,” is proposed, based on the Lean Six Sigma, VSM, and Servqual methods. This model considers and includes three important management systems for an efficient collection value chain: quality management, route management, and HR and community management. The proposed model was implemented and validated in the municipality of Lima, Peru, and the results showed that municipal costs were reduced up to 40%, solid waste was reduced in the streets, and routes and processes were updated and improved in addition to an improvement in the participation and environmental education of citizens. Thus, correct management of the proposed model’s three general approaches to a very positive municipal impact at economic and environmental levels, without the investment of excessive amounts of money observed in first-world countries.
77

Methods to Reduce Malodour Emission from Municipal Solid Waste Fuel / Metoder för att minska utsläpp av dålig lukt från avfallsbränsle

Nehaul, Nico January 2017 (has links)
Swedish power plants have in general an overcapacity which means that they must import waste from abroad. The imported fuel consists of several types of waste, but the majority originates from municipal and commercial waste. EFO is one of the leading fuel supplying and transport companies in Sweden. The company is owned by eight power plants located all around Sweden. The waste is purchased from other countries and then shipped to Sweden. During the unloading of the ship, when the cargo hatches opens, the malodourous gases will escape and be released in to the air. These malodours can travel quite far and are extremely unpleasant to people who live close by. The aim of this thesis was to suggest ways on how to prevent or reduce the emission of malodours during unloading of bales containing municipal waste. The aim of the project was to determine the causes of malodours, to identify the most common odorants in municipal waste, what properties they have, how they can be affected and how to prevent the formation of them. The problem was tackled by theoretical and practical studies. The theoretical study was a literature study and the practical study was observation at Mälarenergi combined heat and power plant. The results are presented as a number of suggestions for how to prevent or reduce the emission of malodours during unloading of bales containing municipal waste. These suggestions were divide in to the three categories Storage, Unloading and At Port. The suggestions varied from using better sorted waste to researching the possibility to use a portable tent covering the cargo ship during unloading. It was recommended that EFO should use both short- and long-term plans and also conduct further research on other ways to reduce emission of malodours.The suggestions were not tested so it cannot with certainty be determined if the suggestions will reduce or prevent emission of malodour. No laboratory tests were done on the waste. Therefore, the contents and concentrations could not be confirmed. However, it is almost certain that even if there were a slight difference it would not lead to a change of the current treatment process of the MSW. Obviously, there should have been multiple observations carried out at Mälarenergi`s power plant on various occasions and at different weather conditions. Several observations should also have been done on EFO´s other power plants to confirm that the core of the malodour emission problem is the same for all power plants. Basing suggestions on results taken from one instance might not give the correct answer to the problem. Common for malodours found in MSW is that they are formed as a product of degrading MSW. Reducing or stopping the degradation process, will prevent the formation of these compounds. This can be done either by lowering the temperature of the waste bales, altering the pH, decreasing the water content and increasing the level of Oxygen. / De svenska kraft- och värmeverken är så effektiva att det svenska bränslet inte räcker till utan man måste importera från andra länder. Bränslet består till stor del av hushållsavfall och kommersiellt avfall. EFO är ett energianskaffnings- och transportföretag som delägs av åtta svenska el- och värmeleverantörer. De förser sina ägare med bränsle till deras kraft- och värmeverk runt om i landet. Majoriteten av det inköpta bränslet kommer från utlandet och fraktas till Sverige med fartyg. Problemet för boende i närområdet är att avfallet avger dålig lukt när det lastas av från fartyg till hamn. Syftet med den här rapporten var att undersöka hur man kan förhindra eller minska utsläpp av dålig lukt vid avlastning från fartyg till hamn samt att ge förslag på metoder som kan minska luktproblematiken. Övriga mål var att fastställa vilka de mest förekommande luktämnena är, orsaken till att de bildas, vilka egenskaper de har och hur man kan förhindra att de bildas. Arbete består av en litteraturstudie tillsammans med observation gjord på Mälarenergis kraftvärmeverk. Resultaten presenterades i form av ett antal förslag på sätt att minska utsläpp av dålig lukt vid avlastning. Dessa förslag indelades i de tre områdena Lagring, Avlastning och Hamn. Förslagen var breda och sträckte sig från användning av bättre sorterat avfall till att utreda om det finns möjligheter till användning av ett portabelt tält kring fartyget under avlastning. Utöver de presenterade förslagen för minskning av luktutsläpp gavs också rekommendationen att EFO bör använda sig av både kortsiktiga och långsiktiga planer samt forska på ytterligare sätt för att minska utsläpp av dålig lukt. Förslagen har inte prövats och det kan därför inte fastställas om de reducerar och förhindrar utsläpp av dålig lukt. Det gjordes heller inte några laboratoriska analyser på avfallets innehåll därför kan det inte bestämmas om avfallet innehåller samma ämnen och koncentrationer. Sannolikt skiljer sig inte värdena så pass mycket att det skulle kräva andra typer av luktreducerande metoder. Fler observationer borde ha gjorts både på Mälarenergis anläggning och på de andra delägarnas anläggningar. Observationerna skulle då också utförts vid olika tidpunkter samt vid olika väderlek. Det är möjligt att resultatet skulle vara annorlunda om det funnits data från fler observationer. Gemensamt för ämnen som avger dålig lukt är att de uppkommer som en produkt av nedbrutet avfall. Genom att bromsa eller stoppa nedbrytningsprocessen kommer uppkomsten av dessa luktämnen förhindras. Detta kan man göra genom att förändra pH, sänka temperaturen, minska fukthalten och öka syrenivån.
78

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.
79

Experimental and feasibility study on co-incineration of sewage sludge and municipal solid waste / 下水汚泥と都市ごみとの混焼に関する実験的検討と実現可能性

Chen, Minhsuan 23 March 2022 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第23870号 / 工博第4957号 / 新制||工||1774(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 高岡 昌輝, 教授 藤原 拓, 准教授 大下 和徹 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
80

Hydrothermal Carbonization as an efficient route for organic waste conversion

Lucian, Michela 28 May 2020 (has links)
The production of municipal solid waste has continued to grow in recent years. In Italy, municipal solid waste production reaches about 29 million tons per year. The organic fraction of municipal solid waste (OFMSW), which accounts for 30-40% of the total waste, usually undergoes biological treatments such as anaerobic digestion or composting, or is incinerated or landfilled. Biological treatments are considered not economically viable due to the long processing time (20-30 days), while incineration and landfilling are considered as low cost but polluting processes. In contrast, Hydrothermal Carbonization (HTC) is a cost-effective process to treat organic waste especially for the shorter processing time (0.5-8 h) and the possibility to treat directly wet heterogeneous materials. This thesis aims to investigate the potential use of HTC to upgrade OFMSW and other biomasses to biofuels or valuable byproducts. Chapter 1 gives an overview on the state of the art of HTC technology applied to organic wastes, focusing both on mechanisms and on the characteristics of reaction products. Chapter 2 investigates the potential use of HTC to upgrade the organic fraction of municipal solid waste (OFMSW) into biofuel and byproducts. The impact of process conditions (process time, temperature and solid load) on the formation, chemical and energy properties of hydrochar was deeply investigated. To analyze the behavior of hydrochar as a solid biofuel, the combustion (oxidation) of hydrochar and the co-firing (co-oxidation) of hydrochars and coals was also investigated. The results show that, especially at HTC harsher conditions, hydrochar is a “coal-like” material, that can be used as a valuable solid biofuel. The results evidenced that hydrochar is composed of primary char and secondary char. Primary char (non-extractable with organic solvents) has characteristics similar to coal and could be recovered for combustion, while secondary char is an amorphous and more volatile solid, easily extracted with organic solvents, which found possible application as a source of biochemicals and liquid bio-fuel. Chapter 3 investigates the use of HTC as a promising pre-treatment to enhance the biomethane potential during anaerobic digestion of OFMSW. Anaerobic digestion experiments were carried out using the HTC process liquid and the entire HTC reaction mixtures. Results proved that, when compared to the raw OFMSW, the use of HTC liquid and HTC mixture into AD lead to an increase of biomethane production of up to 37% and 363% by volume, respectively. Chapter 4 reports an HTC kinetics study and a kinetic model, which accounted for reactions leading to the production of primary and secondary char, as well as the liquid and gas phases. The model was optimized using experimental data performed on a lignocellulosic feedstock (olive trimmings) and validated on two other types of biomasses (grape marc and Opuntia Ficus Indica) and was used as a reliable tool to predict the carbon distribution among HTC products. In this chapter an in-depth analysis was also carried out to understand the evolution of feedstock characteristics during the heat-up transient phase before reaching the HTC set-point temperature. The results show that during heat up, the feedstock carbonized to a considerable extent at 220-250 °C. Tests clearly show evidence of the transition between thermal hydrolysis and HTC. Chapter 5 presents a study conducted to evaluate the economic feasibility and the detailed energy and cost analyses of a hypothetical HTC plant transforming wet biomass into pelletized dry hydrochar. To achieve these goals, a model was developed on the basis of experimental results obtained previously on two other organic materials (grape marc and off-specification compost). The results show that, when operating the HTC plant with grape marc at the optimal HTC conditions (T=220 °C, t=1 h, dry biomass to water ratio=0.19), the production cost of hydrochar were determined to be 157 €/ton, competitive with the price of wood pellets (150-200 €/ton). This makes HTC a promising process for a large development at the industrial scale.

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