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Municipal Solid Waste Management in an urban area of China: Case studies of Shanghai, China and Linköping, Sweden.Yang, Cha January 2011 (has links)
With the rapid and large increase of waste quantities, China, surpassed the USA as the world’s largest municipal solid waste (MSW) generator since 2004. The phenomena and critical issues of MSWM in China inspired this paper to investigate and analyse the MSWM in an urban area of China. Comparing with the increasing rates of MSW generation, little has been done concerning the municipal solid waste management (MSWM). Not only the local government and authorities are responsible for the MSWM, but also the individuals are playing a significant role in MSWM. An integrated waste management system should be built in order to improve the holistic MSW system and reduce the waste production. The aim of the study is to investigate and analyse the current status and problems of MSWM in an urban area of China and to analyse to what extent a viable reduction of the MSW can be implemented and management systems to be improved in the near future. In this study, two case studies of Shanghai and Linköping are employed and compared to explore the challenges and potentials for improving the MSWM system in China. The result indicated that inadequate facilities and infrastructure, less advanced technology, insufficient public participation, low awareness of environmental protection, problems in policy and laws are the major barriers for the improvement of MSWM. Involving international environmental cooperation activities, planning a sustainable and comprehensive policy and framework for MSWM, introducing economic incentive approaches, promoting the capacities of waste management technologies, raising public environmental awareness are believed to be viable solutions to improve the MSWM system in China.
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An evaluation of methane mitigation alternatives for closed municipal landfillsTyree, James Nelson 29 April 2014 (has links)
Countries around the world face social, economic, and ecological damage from escalating natural disasters caused by climate change. In an effort to curtail climate change impacts, local and regional governments are beginning to employ green house gas (GHG) mitigation strategies to reduce their carbon footprint. These strategies work to eliminate a range of GHG emissions from entering the atmosphere. Apart from carbon dioxide (CO₂), the most prevalent GHG is methane. In terms of global warming, methane is approximately 21 times more harmful to the atmosphere than CO₂. Natural gas systems, coal mining, manure management, rice cultivation, wastewater treatment, and landfills all contribute to methane generation. According to the US Environmental Protection Agency's 2011 US GHG inventory, landfills generate 1.5% of total GHG emissions in carbon dioxide equivalents. Recognizing the global impacts of its policies and operations, municipalities are working to reduce their GHG emissions. Coalitions like the C40 Cities Climate Leadership Group were created to specifically address GHG reductions, which will result in a 248 million MT reduction in GHGs released to the atmosphere by 2020. Guided by existing literature, this Master's Report calculates methane generation and transport to determine the effectiveness of applying two methane mitigation alternatives--passive methane oxidation biocovers (PMOBs) and landfill gas to energy technologies (LFGTE)--at an inactive landfill site to reduce GHG emissions. LFGTE generates energy for direct use such as space heating or industrial processes or for electricity generation. Cost-saving strategies abound for landfills which utilize LFGTE. PMOBs optimize the landfill surface soil cover environment to promote microbial growth of bacteria, called methanotrophs, which convert methane into carbon dioxide. When employed, these mitigation alternatives are designed to significantly reduce methane emissions from landfills. The EPA has developed a computer modeling program (LANDGEM) to aid in the calculation of landfill gas generation. A hypothetical case study of a one million ton landfill was created and modeled for methane generation over a 35 year period. With methane generation rates calculated, assessment of potential LFGTE was performed and methane oxidation rate calculations were made to determine the impact of a PMOB and LFGTE on net GHG emissions at the landfill. The overall GHG reductions with these engineering controls were two-thirds of the level a landfill without controls would emit. These results indicate that implementing methane mitigation steps at closed landfills throughout the world would yield significant reductions in GHG emissions. / text
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Hydraulic performance and stability of geosynthetic landfill cover systems with constrained drainage at the outletYates, Trevor Butler 30 September 2011 (has links)
Sliding failures of landfill cover systems are common, and the slip surface is often at the interface between a geosynthetic drainage layer and an underlying textured geomembrane. In an effort to understand the sliding failures, the objectives of this research project are to summarize current regulation and practice in landfill cover design, use experimental methods to characterize the behavior of geosynthetic landfill materials in cover systems approaching failure, and develop models to evaluate the hydraulic performance and stability of landfill cover systems.
Inclined plane tests were conducted to explore the behavior of a geosynthetic drainage material/textured geomembrane interface. The interface had effective normal stress dependent strain softening behavior, with more strain softening measured at higher effective normal stresses.
A numerical model for confined flow in a drainage layer with a constrained outlet was developed. The model was used to evaluate how water fills and empties from a geosynthetic drainage layer for a variety of inflow conditions and constraints to flow at the outlet. The model was used to demonstrate that a drainage layer that effectively conveys water out of a cover system with a free flowing drainage outlet quickly fills with water when the outlet has a modest constraint to flow.
An iterative, numerical model was developed to calculate stability solutions for landfill cover slopes that satisfy force equilibrium and strain compatibility while accounting for effective normal stress dependent strain softening and various pore water pressure conditions. Stability solutions reveal that depending on the water pressure in the drainage layer, the geosynthetic drainage material may experience tension at many points along the slope.
It is crucial for the stability of the landfill cover system to maintain free-flowing conditions at the drainage layer outlet. A modest constraint to flow at the outlet has a significant adverse effect on the ability of the landfill cover drainage layer to convey water out of the system, which can lead to instability. The drainage layer outlet should be designed to ensure free flow of water out of the drainage layer. / text
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BATCH AND BENCH-SCALE FIXED-BED COLUMN EVALUATIONS OF HEAVY METAL REMOVALS FROM AQUEOUS SOLUTIONS AND SYNTHETIC LANDFILL LEACHATE USING LOW-COST NATURAL ADSORBENTSLi, Chenxi 01 February 2008 (has links)
In this project, three separate experiments were conducted to assess heavy metal removal from metal aqueous solutions and synthetic landfill leachate by adsorption using low-cost natural adsorbents.
Fundamental batch investigations indicated that the 4.0-4.75 mm crushed mollusk shells and the Sphagnum peat moss were the best adsorbents for cadmium and nickel removal, respectively. Peat moss was also found to have the highest adsorption capacities for manganese and cobalt adsorption.
The adsorption capacities of the peat moss and crushed mollusk shells used as natural adsorbents for the adsorption of cadmium and nickel from binary aqueous solutions in fixed-bed columns under continuous flow conditions were investigated. The life expectancy of each adsorbent in the fixed-bed columns was also assessed for different hydraulic loading rates. The flow rate of 1.5 mL/min (surface loading of 27.52 cm3/cm2•day) and bed depth of 15 cm were identified as the better operational conditions from the column testing. The results indicated that 47.9% and 42.7% cadmium and nickel removal efficiencies could obtained under these operational conditions, respectively.
Finally, the peat moss and the crushed mollusk shells were packed in bench-scale down-flow fixed-bed columns to evaluate their adsorption capacities as natural low-cost adsorbents for the removal of heavy metals from aerated and non-aerated synthetic landfill leachate. The flow rate applied in this operation was 1.5 mL/min (surface loading of 27.52 cm3/cm2•day). Peat was found to have the best adsorption capacities in columns treating aerated synthetic leachate for cadmium (78.6%) and nickel (83.8%) removal efficiencies. / Thesis (Master, Civil Engineering) -- Queen's University, 2008-01-31 22:37:34.381
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METANO IR BENDROJO DUJŲ KIEKIO KITIMAS RADVILIŠKIO MIESTO SĄVARTYNE 1982-2060 m / The quantity change of methane and total gas in the dump of Radviliškio town during 1982-2060Varapickas, Mindaugas 07 September 2010 (has links)
Bakalauro darbe yra išnagrinėti Lietuvos Respublikos teisės aktai, kurie reglamentuoja atliekų tvarkymą. Apžvelgta Europos Sąjungos atliekų tvarkymo politika bei direktyvos. Pateikti statistiniai duomenys apie Europos Sąjungos ir Lietuvos atliekų susidarymo kiekius ir jų tvarkymą. Pateikta informacija apie atliekų sudėtį, sąvartynus bei sąvartynų dujas. Ištirta Radviliškio miesto sąvartynų dujų kiekio kasmetinės emisijos, pasitelkiant emisijos modelį „LandGEM“. Pasitvirtino dujų susidarymo teorija. Sąvartyno susidarančių dujų kiekio emisija priklauso nuo atliekų amžiaus ir kiekio. Pateiktas galimo sąvartyno dujų panaudojimo būdas. / The bachelor work analyses the legal acts of Lithuania Republic, which fine tune the administration of waste. It also reviews the policy and directives of European waste management. The statistic data has been presented about the composition of waste, dump and dump gas. The annual emission of the quantity of dump gas in Radviliškio has been examined by using the emission model of “LandGEM”. The theory of gas formation has been proved. The emission of formation of gas quantity in a dump depends on the age and quantity of waste. The way of the possible using of dump gas has also presented in this work.
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Experimental investigations of clogging processes and implementation of mitigation measures in landfills / Kolmatacijos procesų eksperimentiniai tyrimai ir lėtinimo priemonių taikymas sąvartynamsBazienė, Kristina 19 June 2013 (has links)
The thesis examines the causes for the clogging problem of municipal landfill leachate collection system. The main aim of the work is to research clogging processes in different fillings by using municipal waste leachate, evaluate the leachate chemical compound concentration changes, and, based on the results of researches, to maintain the conductivity function.
In the graduation thesis, several basic objectives are being solved: to perform column research of the fillings, by using municipal waste landfill leachate, and to identify parameters, identifying the clogging processes of fillings: porosity and porosity coefficient, as well as to analyse their changes; to analyse the concentrations of chemical compounds leachate, having an impact on drainage layer clogging; to evaluate, by applying modelling software, the column filling porosity changes over a period of time.
The thesis consist of an introduction, three chapters, general conclusions, list of references used as well as the list of the author’s publication on the dissertation topic.
The introductory chapter discusses the study problem, the relevance of the work, presents the description of the research object, formulation of the aim and objectives of the work, description of the research methodology, scientific novelty of the work, the practical significance of results, and defensive statements.
The first chapter is the review of literature, as well as examination of: clogging processes in municipal landfill... [to full text] / Disertacijoje nagrinėjama komunalinių atliekų sąvartyno filtrato drenažo sluoksnio kolmatacijos problema. Pagrindinis disertacijos tikslas – ištirti komunalinių atliekų sąvartyno filtrato savybes, kurios apibūdina kolmatacijos procesus drenažo sluoksnyje, surasti tyrimų metu naudojamo drenažo užpildo efektyvią sudėtį, kuri išlaiko laidumo funkciją ir mažiau kenkia aplinkai.
Darbe sprendžiami keli pagrindiniai uždaviniai: nustatyti komunalinių atliekų sąvartyno filtrato cheminius elementus, kurie turi įtakos drenažo sluoksnio kolmatacijai, naudojant komunalinių atliekų sąvartyno filtratą atlikti drenažo sluoksnio, kolonėlės tyrimą su skirtingos sudėties medžiagomis ir nustatyti kolonėlių užpildų poringumo pokyčius, nustatyti tinkamą naudojamų medžiagų (skaldos ir smulkintų naudotų padangų) sudėtį drenažo sluoksnio užpildui formuoti.
Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašas.
Įvadiniame skyriuje aptariama tiriamoji problema, formuluojamas darbo aktualumas, aprašomas tyrimų objektas, formuluojamas darbo tikslas bei uždaviniai, aprašoma tyrimų metodika, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Pirmas skyrius skirtas literatūros analizei. Šiame skyriuje nagrinėjami kolmatacijos procesai, vykstantys komunalinių atliekų sąvartynuose. Skyriuje apžvelgti pasaulyje atlikti mokslininkų kolmatacijos tyrimai, išanalizuoti gauti jų rezultatai. Skyriaus... [toliau žr. visą tekstą]
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Kolmatacijos procesų eksperimentiniai tyrimai ir lėtinimo priemonių taikymas sąvartynams / Experimental investigations of clogging processes and implementation of mitigation measures in landfillsBazienė, Kristina 19 June 2013 (has links)
Disertacijoje nagrinėjama komunalinių atliekų sąvartyno filtrato drenažo sluoksnio kolmatacijos problema. Pagrindinis disertacijos tikslas – ištirti komunalinių atliekų sąvartyno filtrato savybes, kurios apibūdina kolmatacijos procesus drenažo sluoksnyje, surasti tyrimų metu naudojamo drenažo užpildo efektyvią sudėtį, kuri išlaiko laidumo funkciją ir mažiau kenkia aplinkai.
Darbe sprendžiami keli pagrindiniai uždaviniai: nustatyti komunalinių atliekų sąvartyno filtrato cheminius elementus, kurie turi įtakos drenažo sluoksnio kolmatacijai, naudojant komunalinių atliekų sąvartyno filtratą atlikti drenažo sluoksnio, kolonėlės tyrimą su skirtingos sudėties medžiagomis ir nustatyti kolonėlių užpildų poringumo pokyčius, nustatyti tinkamą naudojamų medžiagų (skaldos ir smulkintų naudotų padangų) sudėtį drenažo sluoksnio užpildui formuoti.
Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašas.
Įvadiniame skyriuje aptariama tiriamoji problema, formuluojamas darbo aktualumas, aprašomas tyrimų objektas, formuluojamas darbo tikslas bei uždaviniai, aprašoma tyrimų metodika, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Pirmas skyrius skirtas literatūros analizei. Šiame skyriuje nagrinėjami kolmatacijos procesai, vykstantys komunalinių atliekų sąvartynuose. Skyriuje apžvelgti pasaulyje atlikti mokslininkų kolmatacijos tyrimai, išanalizuoti gauti jų rezultatai. Skyriaus... [toliau žr. visą tekstą] / The thesis examines the causes for the clogging problem of municipal landfill leachate collection system. The main aim of the work is to research clogging processes in different fillings by using municipal waste leachate, evaluate the leachate chemical compound concentration changes, and, based on the results of researches, to maintain the conductivity function.
In the graduation thesis, several basic objectives are being solved: to perform column research of the fillings, by using municipal waste landfill leachate, and to identify parameters, identifying the clogging processes of fillings: porosity and porosity coefficient, as well as to analyse their changes; to analyse the concentrations of chemical compounds leachate, having an impact on drainage layer clogging; to evaluate, by applying modelling software, the column filling porosity changes over a period of time.
The thesis consist of an introduction, three chapters, general conclusions, list of references used as well as the list of the author’s publication on the dissertation topic.
The introductory chapter discusses the study problem, the relevance of the work, presents the description of the research object, formulation of the aim and objectives of the work, description of the research methodology, scientific novelty of the work, the practical significance of results, and defensive statements.
The first chapter is the review of literature, as well as examination of: clogging processes in municipal landfill... [to full text]
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Solar landfills : A study of the concept in a Swedish settingSkoglund, Martin, Mårtensson, Cecilia January 2014 (has links)
The increasing global energy demand, which today is mainly supplied by energy sources with a fossil origin, is a severe threat to the environment and to the security of supply. In order to handle these problems, renewable energy sources are promoted globally as well as nationally in Sweden. Solar photovoltaic (PV) technology is one of the most mature and commercial renewable energy technologies and could play a vital role in phasing out fossil energy sources. In the emerging, promising concept of solar landfills, PV systems are installed on closed landfill sites in order to combine renewable electricity production with resource efficient use of land. In this study the legal, technical and financial aspects concerning a solar landfill project in a Swedish setting were investigated. Additionally, the potential of the concept on a regional level in Sweden was analysed. The methodology used in the study featured literature research, interviews, and a feasibility assessment of a solar landfill project on Visby landfill. Regarding the legal aspects linked to a solar landfill project, an inconsistency between Swedish municipalities concerning the need of a building permit for a ground mounted PV system was revealed in the study. While some municipalities demand a building permit, others do not. Additionally, the fact that a closed landfill usually is classified as an environmentally hazardous activity doesn’t result in any need for additional permissions for a PV system installation on a closed landfill. Therefore, such legal aspects are not likely to hinder a solar landfill project to any great extent. Considering the technical aspects, the choice of mounting system must be done carefully because of the special conditions which exist on a landfill site; such as ground penetration restrictions and risks of settlement. While a ballasted mounting system can avoid ground penetration, a driven pile mounting system generally features a lighter construction. Furthermore, a fixed tilt mounting system is preferred over a sun tracking mounting system due to the extra weight and sensitivity to settlement which comes with the latter choice. Regarding the choice of PV modules, thin film modules generally feature a lower weight and can therefore be advantageous in comparison with crystalline silicon modules. In the case of Visby landfill, where penetration was preferred to be avoided but where the risk of settlement was considered low, the PV system which was deemed most suitable for the site featured a ballasted fixed tilt mounting system with crystalline silicon PV modules. Considering the financial aspects, the study emphasises the importance of using the produced electricity to offset consumed electricity in order to enable a sound investment. This can be done by a wise choice of owning and financing structure where the produced electricity offsets consumed electricity for a large consumer, e.g. an industry or a grocery store, or for a number of residences in a community solar. The economic feasibility also heavily depends on the projects’ possibility to use policy incentives and tax exemptions. The feasibility assessment of Visby landfill showed that the most economically feasible investment was possible by founding a community solar which offsets the members’ consumed electricity. Such an investment would feature a 10 year payback time and an internal rate of return of 8.3 %. Finally, the potential of the solar landfill concept on a regional level was identified as significant. In a scenario where the PV system suggested for Visby landfill in the feasibility assessment is installed on all the suitable landfill sites on Gotland, the island has the possibility to produce 22 GWh of electricity from solar landfills, thereby meeting the regional energy goal set for 2020.
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Microbial Transformation of Organotin Compounds under Simulated Landfill Conditions / Mikrobiell omsättning av tennorganiska föreningar under simulerade deponiförhållandenBjörn, Annika January 2007 (has links)
Mono- and di-alkyltins are used extensively as heat stabilizers for processing of poly vinyl chloride (PVC). Tin mercaptide stabilizers are some of the most effective PVC stabilizers available. The main applications for tin stabilizers are building/construction products, such as pipes, fittings, siding and profiles (windows etc.), packaging and flexible PVC plastics. Most PVC products have been and are subjected to landfilling, when their use is terminated. The structure of the polymer itself and the substances used as additives have been a concern for environmental authorities in many countries since long, which also includes their presence in landfills. In the case of the organotin stabilizers their leaching out from (PVC) plastics into the leachate phase of landfills with the risk for further transport to ground and surface waters is in focus. The main objectives of this thesis take their start in this background and, thus, included the elucidation of whether organotin compounds (OTs) in stabilized PVC products contribute to the pool of OTs observed in landfill leachates and if these compounds are degradable by the microorganisms developing under anaerobic landfill conditions. To reach these aims and the research questions raised the forwarded PVC materials were added to muniscipal solid waste (MSW) processed in containers used to simulate the ageing of landfills under forced conditions. These include traditional landfill simulation reactors (LSRs) at a scale of ca 100 L and also at a smaller scale ca 5 L constructed for the purpose of this study, i.e. the modular environmental test system (METS). The latter were used to investigate temperature effects on the possible release of OTs from different types of PVC materials. The capacity by microorganisms in landfill environments were used to investigate their capacity to degrade or transform organotin stabilizer compounds focused on in this thesis. Differences in this capacity in relation to the ageing of landfills and exposure to the alkyltin stabilizers were studied with microorganisms sampled from LSRs spiked with PVC over time and from landfill site. Access to sensitive and reliable equipment and analytical protocols for the analysis of OTs and their transformation intermediates and end products are prerequisites for this kind of studies. This necessitated an adoption and adaptation of analytical methods for the low concentrations occurring in the environment. Two methods were established and well served the requirements. Indeed OTs migrated out from especially flexible PVC materials, while rigid PVC was less prone for OT release as judged from the METS simulations. The METS studies showed that the OT release increase substantially at higher temperatures and especially so when the temperature was higher than the glass transition of the PVC.materials. The organotin stabilizers were transformed, partly or completely degraded, by anaerobic microorganisms derived from landfill environments. Upon prolonged exposure to OTs leaching from PVC in LSR simulations the microorganisms displayed a higher efficiency in degradation of the leached OTs. The microorganisms would methylate inorganic tin and metyltin present in the MSW material as well as perform dealkylation depending on the tin concentrations prevailing. During these studies it was discovered that the organotin stabilzers were inhibiting the methanogens and fermentative bacteria, which lead to a retardation of the anaerobic mineralisation of the MSW in the assays. An in depth study revealed that the OTs themselves but also their ligands and degradation products from these together effected the inhibition. However, given the extent of leaching in relation to the water flows in landfills, the concentrations will mainly be too low to pose any risks to the surrounding environment.
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Geology and evaluation of potential for contamination of the vicinity of the Metropolitan Landfill, Liberty Township, Delaware County, Indiana using earth resistivity as guidance / Geology and evaluation of potential for contamination.Bailey, Douglas C. January 1987 (has links)
The area immediately surrounding a landfill was studied by DC resistivity methods, soil borings, and review of historical data bases to learn if the landfill had released leachate to the ground water and to define the geology and hydrogeology of the site. Property immediately adjacent to the landfill has been proposed as a new landfill site. The geology and hydrogeology of this site were investigated to provide supplemental data for use in planning and operating the new landfill.Although no contaminant plumes were located by resistivity methods, the range in measured resistivity values proved to be sufficiently large to possibly mask existing leachate migration from the landfill. Using the resistivity data base generated through this effort, future resistivity surveys at this site may identify changes indicating contaminant plume formation or migration.Zones of shallow sand and gravel were found (by resistivity methods) to be present at locations that appear to correlate with slightly higher topography and soil type MuB2. This information led to the location and confirmation of other shallow permeable zones in the glacial drift with the same common attributes (soil type MuB2, higher topography and 5 to 15 feet deep sand and gravel). These shallow permeable zones had been omitted from the ground-water monitoring systems for both the Metropolitan Landfill and the proposed Delaware County Landfill. The results of this study were used as the basis for recommendations presented to the local board of health and the state regarding the need for additional ground-water monitoring at the two sites and the suggested locations for such.
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