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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.
361

Waste Management with Focus on Waste incineration with energyrecovery in Chisinau Municipality, Moldova

Gunnarsson, Martin, Johannesson, Rickard January 2010 (has links)
<p>The amount of waste in the world increases every year due to an improved living standard andgrowing population. The problem is especially large in poor countries where the ability tohandle the waste is limited due to financial and management problems. If instead wastematerial is seen as a resource it can help reduce the amount of waste on landfill. Byincinerating waste and recover the energy it would also help reducing greenhouse gasemissions from landfill and give electric and thermal energy.Chisinau Municipality in the Republic of Moldova today lacks several important parts fora satisfying waste management. Today most of the waste generated in Chisinau municipalityends up at the municipality landfill. The current contract to use the landfill expires on the 31December 2010, if the municipality won’t be able to renew the contract they have to look forother ways to deal with the waste problem. As the dominating source for energy in Chisinau isimported natural gas, an effective way to reduce the use of gas for electricity and thermalenergy production would be to use waste material for incineration with energy recovery.Therefore, the goal with this thesis is to evaluate the possibility to extract energy from coincinerationof sewage sludge and waste material generated in Chisinau. To reach this goal thesituation in Chisinau where studied on site for two months, quantities and composition of thewaste material was investigated. Based on the data gathered on the waste, a suitabletechnology for the waste-to-energy (WTE) plant is proposed. The proposal is made based onthe assumption that a WTE plant would not be established until 2025.The result shows that the waste material in Chisinau can be used for co-incineration ofwaste and sludge. The calorific value of the waste material was determined to 7.87 MJ per kg.The suggested WTE plant has the total power of 138 MW, the result based on that all wastematerial available 2025 are incinerated. Annually this makes it possible to recover 1152 TJ(320 GWh) electric power and 2650 TJ (736 GWh) heat, based on 8000 operating hoursannually.Even if a WTE plant sounds like a good investment it is a long time before a plant couldoperational. Much is to be made in the waste management to have well-functioninginfrastructure that will work together with an incineration plant. Furthermore, the data used inthis study regarding the quantities is very uncertain and further studies in affected areas arenecessary before a WTE plant can be established.</p> / <p>Den totala mängden avfall i världen ökar varje år som följd av ökad folkmängd ochlevnadsstandard. Problemet är extra påtagligt i fattiga länder med begränsade ekonomiskaresurser för att ta hantera avfallet. Om avfallet istället skulle ses som en resurs skulle detkunna reducera andelen avfall som läggs på deponi. Genom att förbränna avfallet medenergiåtervinning skulle också växthusgaserna från deponering minska och samtidigt geelektrisk och termisk energi.Chisinau kommun i Republiken Moldavien saknar idag flera vitala delar iavfallshanteringen. Idag slutar den största delen av avfallet som produceras i Chisinaukommun på den kommunala deponin. Kontraktet för att använda deponin löper ut den sistadecember 2010, om Chisinau kommun inte tillåts förnya kontraktet är det nödvändigt att sesig om efter nya lösningar för avfallshanteringen. Eftersom den dominerande källan för energii Chisinau är importerad gas, skulle ett effektivt sätt att reducera gasanvändningen vid el ochtermisk energiproduktion att förbränna avfall med energiåtervinning.Av den orsaken är målet med studien att utvärdera möjligheterna att utnyttjasamförbränning med energiåtervinning av avfall och avloppsslam från Chisinau kommun. Föratt nå detta mål har den nuvarande situationen i Chisinau kommun studerats på plats under tvåmånaders tid, detta för att undersöka vilka mängder avfall som årligen produceras och huravfallets fraktionsfördelning ser ut. Baserat på de data som samlats in föreslogs en lämpligavfallsförbränningsanläggning. Förslaget är baserat på antagandet att enavfallsförbränningsanläggning inte är etablerad förrän tidigast 2025.Resultatet visar att det är möjligt att samförbränna avloppsslam och avfall i Chisinau. Detkalorimetriska värmevärdet för avfallet och slammet har bestämts till 7.87 MJ per kg. Det irapporten presenterade förslag på kraftvärmeverk för avfallsförbränning kommer att ha entotal effekt av 138 MW, resultatet är baserat på att allt tillgängligt kommunalt avfall 2025förbränns. Kraftvärmeverket beräknas årligen utvinna TJ (320 GWh) elektrisk energi och2650 TJ (736 GWh) termisk energi, beräknad på 8000 drifttimmar årligen.Även om en avfallsförbränningsanläggning låter som en god investering så ligger detlångt fram i tiden innan en sådan anläggning är möjlig att etablera. Först måste en brafungerande infrastruktur som fungerar tillsammans med avfallsförbränningsanläggningenupprättas. Vidare bör poängteras att de data som använts i denna studie gällandeavfallsmängder är ytterst osäkra och ytterligare studier inom området krävs innan enavfallsförbränningsanläggning kan etableras.</p>
362

WORK WITH AGENDA 21 IN EUROPEAN CITIES. : A case of study: the waste's management in Barcelona and Gävle

Abad, Marta January 2008 (has links)
<p>Sweden is a long-term world reference country in terms of sustainable development. On the other hand, Barcelona has recently made great efforts in order to improve and to make society aware of the importance of environmental issues. Hence, it would be interesting to investigate if these efforts had succeeded in the waste’s management in Barcelona compared to other leading European cities, and particularly to the case of Gävle.</p><p>In this work, the operation of the management of the urban solid wastes of the two cities is explained.</p><p>First, the objectives marked by Agenda 21 of each locality are exposed. Next, a theoretical perspective about management, generation of wastes and types of waste treatment is provided. In the following chapter, the results of the generation of wastes, selective collection and the treatments of the wastes are shown for both the cases of Barcelona and Gävle until the 2006.</p><p>Finally, the two cities are compared and the results obtained in the management of the wastes are discussed.</p><p>The conclusion in this study is that Barcelona has improved noticeable in terms of environmentally safe management of the wastes. This has happened thanks to the efforts of the city council and of the citizens.</p><p>But It is still necessary to make a major effort by the inhabitants of Barcelona.</p>
363

The Power of Waste : A Study of Socio-Political Relations in Mexico City’s Waste Management System

Frykman, Carina January 2006 (has links)
<p>Abstract</p><p>It is estimated that up to 2 percent of the population in Third World countries survives on waste in one way or another. In Mexico City alone there exist 15,000 garbage scavengers called Pepenadores. The poverty and marginalization they experience is utterly linked to their work, and while they do much of the hard work their socio-economic situation seems stagnant. This paper explores the complexity of the waste management system in Mexico City which keeps them in this position, and how the current system is a manifestation of the existing symbiosis between the formal and informal sectors of the city.The main characters in the maintenance of this system are the leaders of waste management associations.Their struggle to maintain their powerful positions influences both the system’s relationship to the public sector and determines the socioeconomic situation of the Pepenadores.The paper also analyzes the effects of past efforts to change the system, and how policy changes always seem to work against the Pepenadores. Efforts to help the Pepenadores escape their vulnerable positions can be successful in the short-term, but the existing social structure in Mexico City make any permanent changes difficult to achieve.</p>
364

Deposition of sub-micron and micron-sized particles from combustion of black liquor

Sinquefield, Scott Alan 15 October 1998 (has links)
Black liquor recovery boilers experience significant fire-side fouling problems due to the deposition of entrained particulate matter. Increased understanding of the mechanisms by which particles deposit on these surfaces will lead to more effective management of the resultant problems. There is some evidence which suggests that the sub-micron fraction of this particulate matter deposits by thermophoresis. In an effort to determine conclusively if this is the case, a facility (the Multifuel Combustor at Sandia National Laboratories) was used which could generate and deposit fly ash under conditions that mimic those found in full scale recovery boilers, and dynamically monitor deposit growth rates. Experiments where both the deposit thickness and surface temperature were monitored in situ resulted in linear deposit growth rates despite highly non-linear surface temperature increases. This rules out thermophoresis as the dominant deposition mechanism since it is dependent on the changing thermal driving force. The morphology of the windward side deposit indicates an inertially-dependent mechanism is at work in spite of the size of the particles, which are considerably smaller than what would be commonly considered inertially impacting particles. Leeward side deposits also grow linearly, indicating that thermophoresis, although possibly contributing to deposition, is not the rate-controlling mechanism. Deposition efficiencies fell in the range of 5-15%. The morphology of the sub-micron deposits is highly structured and dendritic in appearance, with over 90% voidage. The particles form long strings or filaments which grow in parallel, indicating that the particles have a high sticking efficiency and do not roll or settle subsequent to impacting. There is minimal contact between adjacent filaments. Recently published research confirms the presence of particles in the 1-50 micron range in recovery boilers. Deposition experiments were performed on this size range as well. Termed Intermediate-size, these particles deposit many times more efficiently, and produce linear deposit growth rates just as the sub-micron particles. They also deposited in clusters of filaments which grew rapidly upward and slowly outward until the adjacent clusters merged. However in this size range the clusters tended to branch out more rapidly than the sub-micron deposits. Deposition efficiencies fell in the range of 40-65%. / Graduation date: 1999
365

The Power of Waste : A Study of Socio-Political Relations in Mexico City’s Waste Management System

Frykman, Carina January 2006 (has links)
Abstract It is estimated that up to 2 percent of the population in Third World countries survives on waste in one way or another. In Mexico City alone there exist 15,000 garbage scavengers called Pepenadores. The poverty and marginalization they experience is utterly linked to their work, and while they do much of the hard work their socio-economic situation seems stagnant. This paper explores the complexity of the waste management system in Mexico City which keeps them in this position, and how the current system is a manifestation of the existing symbiosis between the formal and informal sectors of the city.The main characters in the maintenance of this system are the leaders of waste management associations.Their struggle to maintain their powerful positions influences both the system’s relationship to the public sector and determines the socioeconomic situation of the Pepenadores.The paper also analyzes the effects of past efforts to change the system, and how policy changes always seem to work against the Pepenadores. Efforts to help the Pepenadores escape their vulnerable positions can be successful in the short-term, but the existing social structure in Mexico City make any permanent changes difficult to achieve.
366

Site Suitability Analysis for an Intermountain Solid Waste Facility: A Study for Cache County, Utah

Campo, Joseph B. 01 January 1996 (has links)
The goal of this project was to analyze Cache County for potential sanitary landfill sites covering the period 2020 to 2120. The county population and per capita solid waste were estimated. The minimum landfill size was then calculated. A geographic information system (GIS) was used for data storage and vii analysis. Relevant data were gathered. Areas which would not support a landfill were eliminated. Remaining sites were rated as having slight, moderate, or severe restrictions for use as an area method sanitary landfill based on the Natural Resource Conservation Service (NRCS) Sanitary Facility Report, and the NRCS Soil Interpretations Rating Guide. Seventeen sites were designated as sites for further evaluation. A landfill ranking system giving a primary and/or secondary rating to data items was developed. Nine prime sites had one secondary (.,a ting. These sites should be more closely investigated to determine which are the best potential sites. (136 pages)
367

Integrated Solid Waste Management : A Possible Solution to Environmental and Sanitation Problems in the Ancient City of Ibadan, Oyo State, Nigeria

Komolafe, Sunday January 2012 (has links)
The quantity of solid waste generated in Nigeria has increased at an alarming rate over the decades with lack of efficient and sustainable waste management in most cities of the country. This can be attributed to incessant increase in population, expansion of urban areas, industrialization and consumption rates. This study focuses on the ancient city of Ibadan and used Ibadan North Local Government as the case study. There are many environmental and sanitation problems in Ibadan due to improper waste management by the stakeholders involved. The result and analysis of the situation reveals that there are indications that most residents are ignorant of waste handling methods irrespective of their educational and economic status coupled with poor management of waste and lack of good environmental policy. The study analyzes options for adopting Integrated Solid Waste Management (ISWM) which comprises of waste hierarchy. Activities of Oyo State Solid Waste Management Authority (OSSWMA), Ibadan North Local Government (IBNLG) and Private Refuse Contractors (PRCs) in terms of technical know-how, financial capacity and waste equipment are not adequate to meet the tasks. In order to overcome these challenges, this research work discusses if and how Integrated Solid Waste Management can be implemented.
368

A Systematic Comparison of Municipal Solid Waste Management Systems: Case Studies of Dalian City, China and the Region of Waterloo, Canada

Chen, Xudong 06 1900 (has links)
Since the 1990s, Municipal Solid Waste Management (MSWM) has shifted to a more comprehensive approach with an emphasis on managing Municipal Solid Waste (MSW) through the whole process from generation to disposal. Meanwhile, developing countries started to alter their ways of managing wastes and engage in more efforts on waste diversion. Due to their shortage of both resources and expertise, developing countries usually refer to and learn from developed countries’ experiences in MSWM to improve their own practices. How and to what extent these experiences are helpful for developing countries remains inconclusive because significant differences are present among MSWM systems in different countries. These differences do not simply reflect the variations in regulations and resource allocation; more importantly, they reflect the variations in the underlying connections between MSWM and other social, economic, demographic, and technological conditions. Therefore, a systematic examination is needed to enhance the understanding of these differences, the reasons for these differences, and the priorities that need to be stressed in order to improve waste diversion in a particular case. A systematic model, as the framework for the comparison in this thesis, is proposed to illustrate MSMW systems. Based on the model, this thesis compares and contrasts two cases, the Regional Municipality of Waterloo (RMOW) in Canada and Dalian City in China, at multiple levels: overall stage, system components, system structures, and interactions. The results show that Dalian, compared with the RMOW, has less sufficient capacities for waste planning and implementation. Challenges in MSWM are associated with higher density of residences, difficulties in managing informal profit-driven recycling activities, insufficient and unreliable treatment capacity, insufficient multi-agent dialogues and cooperation both within the government and between the public and private sectors, and less specific, program-based public education. The majority of participants in the RMOW are more self-motivated as opposed to the majority in Dalian who are motivated more by compensations. Based on the comparison, implications and suggestions in several aspects concerning waste planning are discussed. From the systematic perspective, to improve waste diversion in Dalian requires collaborative efforts of multiple agents. The key aspect is to strengthen the relatively incompetent component in the system to improve the capacities for waste service and treatment, which are contingent on the development of waste industries. In Dalian, waste diversion should begin with limited types of wastes and gradually expand the scope, and new programs should be designed based on the existing system with cooperation of the informal sector. Meanwhile, cooperation among governmental divisions and between public and private sectors need to be promoted by encouraging multi-agent dialogues and improving information transparency. Program promotion also needs to be more specific in instructions and to address both pro- environmental attitudes and service quality and convenience. Finally, scavenging at landfill sites should be discouraged in order to protect scavengers from the detrimental working environment.
369

WORK WITH AGENDA 21 IN EUROPEAN CITIES. : A case of study: the waste's management in Barcelona and Gävle

Abad, Marta January 2008 (has links)
Sweden is a long-term world reference country in terms of sustainable development. On the other hand, Barcelona has recently made great efforts in order to improve and to make society aware of the importance of environmental issues. Hence, it would be interesting to investigate if these efforts had succeeded in the waste’s management in Barcelona compared to other leading European cities, and particularly to the case of Gävle. In this work, the operation of the management of the urban solid wastes of the two cities is explained. First, the objectives marked by Agenda 21 of each locality are exposed. Next, a theoretical perspective about management, generation of wastes and types of waste treatment is provided. In the following chapter, the results of the generation of wastes, selective collection and the treatments of the wastes are shown for both the cases of Barcelona and Gävle until the 2006. Finally, the two cities are compared and the results obtained in the management of the wastes are discussed. The conclusion in this study is that Barcelona has improved noticeable in terms of environmentally safe management of the wastes. This has happened thanks to the efforts of the city council and of the citizens. But It is still necessary to make a major effort by the inhabitants of Barcelona.
370

Waste Management with Focus on Waste incineration with energyrecovery in Chisinau Municipality, Moldova

Gunnarsson, Martin, Johannesson, Rickard January 2010 (has links)
The amount of waste in the world increases every year due to an improved living standard andgrowing population. The problem is especially large in poor countries where the ability tohandle the waste is limited due to financial and management problems. If instead wastematerial is seen as a resource it can help reduce the amount of waste on landfill. Byincinerating waste and recover the energy it would also help reducing greenhouse gasemissions from landfill and give electric and thermal energy.Chisinau Municipality in the Republic of Moldova today lacks several important parts fora satisfying waste management. Today most of the waste generated in Chisinau municipalityends up at the municipality landfill. The current contract to use the landfill expires on the 31December 2010, if the municipality won’t be able to renew the contract they have to look forother ways to deal with the waste problem. As the dominating source for energy in Chisinau isimported natural gas, an effective way to reduce the use of gas for electricity and thermalenergy production would be to use waste material for incineration with energy recovery.Therefore, the goal with this thesis is to evaluate the possibility to extract energy from coincinerationof sewage sludge and waste material generated in Chisinau. To reach this goal thesituation in Chisinau where studied on site for two months, quantities and composition of thewaste material was investigated. Based on the data gathered on the waste, a suitabletechnology for the waste-to-energy (WTE) plant is proposed. The proposal is made based onthe assumption that a WTE plant would not be established until 2025.The result shows that the waste material in Chisinau can be used for co-incineration ofwaste and sludge. The calorific value of the waste material was determined to 7.87 MJ per kg.The suggested WTE plant has the total power of 138 MW, the result based on that all wastematerial available 2025 are incinerated. Annually this makes it possible to recover 1152 TJ(320 GWh) electric power and 2650 TJ (736 GWh) heat, based on 8000 operating hoursannually.Even if a WTE plant sounds like a good investment it is a long time before a plant couldoperational. Much is to be made in the waste management to have well-functioninginfrastructure that will work together with an incineration plant. Furthermore, the data used inthis study regarding the quantities is very uncertain and further studies in affected areas arenecessary before a WTE plant can be established. / Den totala mängden avfall i världen ökar varje år som följd av ökad folkmängd ochlevnadsstandard. Problemet är extra påtagligt i fattiga länder med begränsade ekonomiskaresurser för att ta hantera avfallet. Om avfallet istället skulle ses som en resurs skulle detkunna reducera andelen avfall som läggs på deponi. Genom att förbränna avfallet medenergiåtervinning skulle också växthusgaserna från deponering minska och samtidigt geelektrisk och termisk energi.Chisinau kommun i Republiken Moldavien saknar idag flera vitala delar iavfallshanteringen. Idag slutar den största delen av avfallet som produceras i Chisinaukommun på den kommunala deponin. Kontraktet för att använda deponin löper ut den sistadecember 2010, om Chisinau kommun inte tillåts förnya kontraktet är det nödvändigt att sesig om efter nya lösningar för avfallshanteringen. Eftersom den dominerande källan för energii Chisinau är importerad gas, skulle ett effektivt sätt att reducera gasanvändningen vid el ochtermisk energiproduktion att förbränna avfall med energiåtervinning.Av den orsaken är målet med studien att utvärdera möjligheterna att utnyttjasamförbränning med energiåtervinning av avfall och avloppsslam från Chisinau kommun. Föratt nå detta mål har den nuvarande situationen i Chisinau kommun studerats på plats under tvåmånaders tid, detta för att undersöka vilka mängder avfall som årligen produceras och huravfallets fraktionsfördelning ser ut. Baserat på de data som samlats in föreslogs en lämpligavfallsförbränningsanläggning. Förslaget är baserat på antagandet att enavfallsförbränningsanläggning inte är etablerad förrän tidigast 2025.Resultatet visar att det är möjligt att samförbränna avloppsslam och avfall i Chisinau. Detkalorimetriska värmevärdet för avfallet och slammet har bestämts till 7.87 MJ per kg. Det irapporten presenterade förslag på kraftvärmeverk för avfallsförbränning kommer att ha entotal effekt av 138 MW, resultatet är baserat på att allt tillgängligt kommunalt avfall 2025förbränns. Kraftvärmeverket beräknas årligen utvinna TJ (320 GWh) elektrisk energi och2650 TJ (736 GWh) termisk energi, beräknad på 8000 drifttimmar årligen.Även om en avfallsförbränningsanläggning låter som en god investering så ligger detlångt fram i tiden innan en sådan anläggning är möjlig att etablera. Först måste en brafungerande infrastruktur som fungerar tillsammans med avfallsförbränningsanläggningenupprättas. Vidare bör poängteras att de data som använts i denna studie gällandeavfallsmängder är ytterst osäkra och ytterligare studier inom området krävs innan enavfallsförbränningsanläggning kan etableras.

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