No description available.

ABSTRACT Bioreactor landfill operation has been promoted as a means of accelerating the degradation of waste for over 30 years. Accelerating the degradation of waste enables better predictability in biogas production and reduces aftercare costs. Most bioreactor landfill trials focus on the effect of leachate recirculation on otherwise conventional landfill cells. However, there is a range of design and operational measures that can be implemented with standard landfilling machinery to further enhance degradation. This thesis explores degradation rates that can be achieved in a landfill cell, designed to maximise degradation rate, with the constraint that it be constructed by standard earthmoving equipment, the waste be crudely shredded by sheep foot compactors to expose waste, and leachate recirculation be operable by landfill personnel. The major departures of these test cells from a conventional landfill cell operation were: the cells were only 3m deep; MSW loaded into the cell was crushed and bags ruptured with a sheep foot compactor; MSW was pre-mixed prior placement with digested sludge, as a ratio such that the buffering capacity of the sludge was equivalent to an amount of NaHCO3 known to successfully buffer the digestion of packed beds of MSW (10gL-1 NaHCO3 in packed bed at field capacity moisture content plus excess leachate equal to 10% of the bed volume (Lai et al 2001); and the waste was placed rather than compacted into the cell. The thesis examines the performance of two test cells, the second only containing MSW and inoculated and buffered by sequencing with the first. These performances are compared with an exhaustive set of control digestions in 200L laboratory reactors. The laboratory reactors were packed with 50kg sub-samples of the waste used in the cells, shredded to sub 5cm size. The laboratory reactors primarily focussed on the effect of temperature on degradation rates, to identify the optimum degradation rate for this sludge and MSW mixture. The laboratory scale reactors produced 231 L and 202 L of methane per kgVS at the mesophilic temperatures of 38°C and 45°C respectively. The degradation was faster in the 45°C reactor where methane production was completely exhausted after 35 days. A laboratory reactor operated at 55°C reactor showed little degradation activity. The pH of this reactor was initially over 8.5, and ammonia inhibition was suspected. However, the reactor did not respond to pH adjustments with hydrochloric acid, and subsequent step decreases in temperature did not have an effect until 47°C, where degradation suddenly accelerated. This suggests the methanogenic consortia in the sludge could not adapt to thermophilic temperatures. This was confirmed in the 63°C reactor which acidified and did not produce methane, until leachate from this reactor was transferred to the 45°C reactor where an established methanogenic community converted the soluble COD to methane. In order to compare laboratory reactor performance with the general literature, pure cellulose was added in a fed-batch fashion to the stabilised 38°C and 47°C leach-beds. The beds were fed under starved conditions, to clearly distinguish degradation products from the cellulose from background levels. This also allowed for the estimation of biomass growth by measuring the uptake of NH4-N, as all other bio-available N sources such as protein and amino acids were reduced to NH4-N under these starved conditions. Hydrolysis rates were determined to be 0.12±0.01 d-1 and 0.14±0.026 d-1 at the 38°C and 47°C temperatures. Degradation in the two test cells was completed within a 7 month period. Temperature in the cells was maintained between 25 – 30°C by biological activity, levels that were above ambient temperatures, but below ideal mesophilic conditions. Methane composition rapidly approached 50% in both cells, and biogas flow rates were consistent with a degradation timeframe in the order of less than year. Full flow rate data was not obtained from these trials due to mechanical problems with flow meters, however vigorous gas production was evident throughout the trial by monitoring gas composition, and the ballooning effect of the top cover. To confirm the degradation rates in the test cells, samples were collected from the second test cell and digested in laboratory reactors. Methane yields were only 2.4 and 6.4 L CH4 kgVS-1 confirming virtual exhaustion of biogas potential within 7 months of sequencing this MSW cell with the first MSW:sludge test cell. This is the first systematic experimental program that places the degradation performance of a test cell in the context of the potential degradation rate achievable with fine shredding, temperature control and thorough inoculation and buffering. Economically, in cases where degradation residues are left insitu as in landfills, the degradation enhancement in the test cells would effectively yield as much benefit as enhancing the degradation rate to a two to three week timeframe typical of an anaerobic digester (Clarke 2000).

Made available in DSpace on 2015-04-11T13:54:57Z (GMT). No. of bitstreams: 1 Dissertacao Wanderlei Pires da Silva.pdf: 2987112 bytes, checksum: 949d7d9c015542bede48e81ae311af9f (MD5) Previous issue date: 2008-09-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Since the Manaus Free Trade Zone creation in 1967 the solid wastes become serious problem in whole urban Manaus City. In 2002, the generation of per capita Municipal Solid Waste (MSW) in Manaus was 1 kg/inhabit./day in average, representing a production of 1,300 t/day. The objectives this present work were i) evaluating the Manaus inhabitant perception on the MSW and the recycling, ii) characterizing the current form of MSW management applied, and iii) proposing a alternative program for MSW managing for town hall of the Manaus. Structured questionnaires were applied in six Manaus geographical zones in which the inhabitants answered on socioeconomic, MSW problems, recycling several aspects, separate collection questions. Findings showed that the Manaus town hall public politics have been completely deficient for solving the MSW problems. However, the results also revealed Manaus inhabitants having a good perception on MSW problems. The respondents were agreed with the implantation of an alternative MSW management including separate collection. / A partir da criação da Zona Franca de Manaus, em 1967, os resíduos sólidos urbanos se tornaram um sério problema em toda a área urbana da cidade de Manaus. Em 2002, a geração de RSU per capita em Manaus era de 1 kg/hab./dia, em média, o que significava uma produção de 1.300 t/dia. Os objetivos do presente trabalho foram: i) avaliar a percepção sobre RSU e reciclagem dos habitantes de Manaus, ii) caracterizar a forma atual de manejo dos RSU praticada e iii) propor um programa alternativo para o gerenciamento de RSU no município de Manaus. Questionários estruturados foram aplicados em seis zonas geográficas de Manaus, nos quais os habitantes responderam sobre questões sócio-economicas, problemas de RSU, vários aspectos da reciclagem e coleta seletiva. Os resultados mostraram que as políticas públicas do município de Manaus tem sido completamente deficientes para resolver o problema dos RSU. Entretanto, os resultados reveleram também que os habitants de Manaus têm boa percepção sobre os problemas de RSU. Os entrevistados se mostraram receptivos à implantação de um programa alternativo de gerenciamento de RSU, incluindo coleta seletiva.

Submitted by Viviane Lima da Cunha (viviane@biblioteca.ufpb.br) on 2017-07-20T14:41:45Z No. of bitstreams: 1 arquivototal.pdf: 8524712 bytes, checksum: 10cc509b4ffc9e5eb995bb5d5ab575d5 (MD5) / Made available in DSpace on 2017-07-20T14:41:45Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 8524712 bytes, checksum: 10cc509b4ffc9e5eb995bb5d5ab575d5 (MD5) Previous issue date: 2016-03-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In order to know and understand the relationship between Municipal Solid Wastes (MSW) generation and demographic, economic and cultural aspects of the population, for example, mathematical models can be employed. In this context, the objective of this study was to develop mathematical models to predict the amount of MSW generated, based on the database from Sistema Nacional de Informações sobre Saneamento – SNIS, and socioeconomic variables. Multiple regression was used. Because of the high diversity of municipalities in Brazil, the sample was grouped into some class of population size and income. It was formulated models for each of the dependent variables: mass of MSW, per capita generation rate 1 (calculated based on the municipal urban population) and per capita generation rate 2 (calculated based on the municipal total population). About 25% of database was saved for models validation. Results showed that grouping the sample based on the municipal population resulted in valid models for almost all the class and that for municipalities with population up to 3,000,000 inhabitants the generation of USW increased with increasing population. When grouping the sample by population classes and income subclasses it was observed that, for municipalities with population between 30,001 and 100,000 inhabitants, which had not presented any valid model for the condition adopted, presented one valid model for income rate above R$ 29,000.00 per capita. For population up to 250,000 inhabitants, it was observed a direct correlation between MSW generation intensity and income level. When grouping the sample into income classes and population subclasses, the analysis of per capita generation rate showed that an increase on the municipal population is associated with an increase on the MSW generation intensity. The valid models formulates presents mean relative error of 23%, and can be employed at municipalities that corresponds to 60.1% of Brazilian population (relative to the year 2015). Given such results, it can be concluded that the generation of MSW was related to the income level and size of the municipal population. Moreover, results showed that the per capita generation rate calculated based on the total municipal population presented a more uniform behaviour than that of the per capita generation rate calculated based on the total urban population, possibly because the degree of uncertainty associated with the prediction of the urban population of the municipality. It was possible develop mathematical models for mass MSW and to rates 1 and 2 of MSW. / A fim de conhecer, bem como, entender a relação da geração dos Resíduos Sólidos Urbanos (RSU) com os aspectos demográficos, econômicos e culturais da população, por exemplo, modelos matemáticos podem ser utilizados. Dessa forma, o objetivo do presente trabalho foi formular modelos matemáticos a partir de informações disponíveis no banco de dados do Sistema Nacional de Informações sobre Saneamento – SNIS, capazes de estimar a geração de RSU em municípios do Brasil, a partir de indicadores de renda e porte dos municípios. Para tal, foi utilizada a análise de regressão múltipla. Em função da grande heterogeneidade nas características dos municípios brasileiros, a amostra foi dividida em diferentes classes de população e renda. Formulou-se modelos para cada uma das variáveis dependentes: massa de RSU, taxa 1 RSU (calculada com base na população urbana do município) e taxa 2 de RSU RSU (calculada com base na população total do município). Foi separado aproximadamente 25% do total de dados, em cada classificação, para validação dos modelos. Os resultados mostraram que o agrupamento da amostra com base na população do município apresentou modelos válidos para quase todas as classes e que em municípios com até 3.000.000 habitantes a produção de RSU aumentou nos municípios mais populosos. Ao agrupar a amostra com base na população e subclasses de renda do município, observou-se que a classe de municípios com população entre 30.001 e 100.000 habitantes, a qual não possuía um modelo dentro da limitação fixada, apresentou um modelo válido para estimativa da geração de RSU em municípios com PIB per capita superior a 29 mil reais. Ainda com base no mesmo agrupamento, percebeu-se que para municípios com até 250.000 habitantes a geração per capita de RSU é diretamente proporcional à renda. No agrupamento da amostra com base na renda e subclasses de população, a análise dos dados de geração per capita permitiu concluir que o aumento do porte do município é acompanhado pelo crescimento da geração per capita de RSU. Os modelos formulados apresentaram média do erro percentual de 23% e contemplam um total de municípios que abrangem a 60,1% da população (relativa ao ano de 2015) total do Brasil. Diante dos resultados, pôde-se concluir que a geração de RSU esteve relacionada ao porte e à renda do município. Percebeu-se ainda que a taxa 2 de RSU apresentou comportamento mais estável que a taxa 1 de RSU, possivelmente devido a menor imprecisão na estimativa da população total do município, em comparação com a estimativa da população urbana do mesmo. Foi possível delinear modelos para a massa de RSU, bem como para as taxas 1 e 2 de RSU.

The objective of this study is to illustrate that phase separation improves the efficiency of an anaerobic system which digests semi-solid organic wastes. Organic fraction of municipal solid waste (OFMSW) was the semi-solid organic waste investigated. In the first part of the study, the optimum operational conditions for acidified reactor were determined by considering the volatile solid (VS) reductions and average acidification percentages at the end of two experimental sets conducted. Organic loading rate (OLR) of 15 g VS/L.day, pH value of 5.5 and hydraulic retention time (HRT) of 2 days were determined to be the optimum operational conditions for the acidification step. Maximum total volatile fatty acid and average acidification percentage were determined as 12405 mg as HAc/L and 28%, respectively in the reactor operated at optimum conditions. In the second part, an acidification reactor was operated at the optimum conditions determined in the first part. The effluents taken from this reactor as well as the waste stock used to feed this reactor were used as substrate in the biochemical methane potential (BMP) test. The results of BMP test revealed that the reactors fed by acidified samples indicated higher total chemical oxygen demand (tCOD) removals (39%), VS reductions (67%) and cumulative gas productions (265 mL). The result of this study indicated that the separation of the reactors could lead efficiency enhancement in the systems providing that effective control was achieved on acidified reactors.

Objective knowledge about quantity, composition and physicochemical characteristics of municipal solid waste (MSW) in the Czech Republic will form the basis for decision- making when considering processing facilities or regional waste management systems. As the country continues to streamline its legislation to the European Union's solid waste mandates, the results of these studies were employed by the Czech Ministry of Environment to optimise the national waste management strategy. This doctoral thesis focuses on the composition of MSW, primarily the mixed MSW from three types of households in the Czech Republic (urban, mixed and rural) differentiated by their heating methods and possibility of waste disposal. The respective experimental work and data-collection took place in years 2008 and 2009. Methodology used in the analyses is based on the sieve analysis of mixed MSW within predetermined grain size fraction and on the final manual sorting of the waste by material categories. The physicochemical characteristics were measured according to the standard analysis methods. The composition of mixed MSW in urban and mixed households are similar. Some of the biggest differences were found in the quantities of certain subsample categories, especially fine fraction (matter smaller than 8 mm), between...

Waste can be considered as an urban burden or as a valuable resource depending on how it ismanaged. Different waste treatment technologies are available at present to manage municipal solidwaste (MSW). Various actors are involved to develop waste treatment technology for certain area.The aim of this study is to analyze the driving forces in technical development in waste sector inSweden. The study is also done to identify emerging waste management technology in Sweden.Moreover, a comparative study of existing and emerging technologies is done by Life CycleAssessment (LCA) model. An extensive literature review and pilot questionnaire survey among thewaste management professionals’ is done for the study. LCA model is developed by SimaProsoftware CML2 baseline method is used for identifying environmental burden from the wastetechnologies.Dry composting, Pyrolysis-Gasification (P-G), Plasma-Arc are identified as potential emergingtechnologies for waste management system in Sweden. Technical developments of thesetechnologies are influenced by indigenous people’s behavior, waste characteristics, regulations, healthor environmental impact and global climate change. Comparative LCA model of P-G andIncineration shows that, P-G is a favorable waste treatment technology than Incineration for MSW,especially in acidification, global warming and aquatic eco-toxicity impact categories.

Nowadays, municipal solid waste (MSW) has got great attention from world-wide decision makers in the field of waste management. When they are making a MSW management decision, there are lots of factors that may influence their final decision for picking up an optimal alternative. In order to find out the influence factors in municipal solid waste management decision-making, incineration and anaerobic fermentation techniques are selected as example for comparison. Literature study and interview are used for collecting theoretical and practical information respectively. A list of theoretical influence factors is created, which integrates environmental, social and financial aspects of incineration and anaerobic fermentation. This list can help the decision-maker to have a better choice when they are choosing an alternative from MSW management methods. Practical information is achieved by interviewing the City of Stockholm Waste Management Administration. Differences are revealed between theory and the Stockholm case. The priority of each influence factor is discussed in this paper. Base on the decision between theoretical factors and the Stockholm case, the result shows that the theoretical factors are not completely sufficient for the practical use in the city of Stockholm. The list of theoretical influence factors should be extended by integrating more factors and more MSW management alternatives to meet different requirements in practical cases. There is no clear definition on which factor has the highest degree of influence for the decision-maker. The priority of influence factors is depended on the local condition and subjective choice of decision-maker. / www.ima.kth.se

Curitiba is a city of two million inhabitants located in the South of Brazil. It is a pioneer in waste management in the country, and is famous for its programs promoting recycling and organic waste collection. The city is now willing to take waste management one step further by investigating new solutions to treat and recover energy from organic municipal solid waste. This report is the fruit of a collaboration between two departments of the municipality of Curitiba, four local universities, the Swedish environment protection agency and the Royal Institute of Technology – KTH. The purpose of this report is to assess the potential for the development of anaerobic digestion as a solution to treat the organic municipal solid waste generated in Curitiba. The report offers an overview of the current waste treatment and of the main sources of organic waste in Curitiba. The annual amount of organic waste generated in the city is estimated to 144,350 tons, of which 913 tons come from food markets supervised by SMAB, the secretary of food supply. Three different scenarios, corresponding to three ranges of waste sources, have been considered. In the first one, the organic wastes generated by one of the two public markets of Curitiba are treated on-site. In the second one, all the organic wastes from food markets, street markets and popular restaurants are treated together in a medium-scale anaerobic digester. In the third one, all the sources of organic municipal solid waste identified in Curitiba are considered, including residential, institutional and small commercial waste. The annual methane production is estimated to 5,400 m3, 86,000 m3 and 12,600,000 m3 respectively for the three scenarios. In the last two scenarios, the methane could be converted into electricity, resulting in an annual electricity production of 257 MWh and 37,600 MWh. The first scenario does not consider a post-treatment of the digestate remaining at the end of the digestion. Between 46 and 50 tons of digestate could be used as a liquid fertilizer on-site and the surplus could be sold. For the two other scenarios, the digestate would be dewatered and composted to be sold as a dry fertilizer. The dry fertilizer production is estimated to 386 tons and 63,000 tons respectively every year. Each of the scenario considered would be financially viable, with a discounted payback period varying from 8 months for the small-scale scenario, to over 15 years for the second scenario. The third scenario would be the most lucrative, with a net present value of about 150 million reals. / Curitiba i Södra Brasilien är en stad med två miljoner invånare som har positionerat sig som pionjär inom avfallshantering. Staden är känd i landet med sin främjande strategi för återvinning och organisk avfallshantering. Curitiba planerar att undersöka och experimentera med nya metoder för behandling av avfall kombinerad med energiåtervinning från kommunalt organiskt avfall. Denna rapport är resultat av ett samarbete mellan två avdelningar inom Curitibas kommun, fyra lokala universitet, Sveriges miljöskyddsmyndighet och den Kungliga Tekniska Högskolan. Syftet med denna rapport är att utvärdera den potentialen som den anaeroba nedbrytningen har som medel för behandling av det kommunala fasta avfallet som genereras i Curitiba. Rapporten går även igenom hur avfallshanteringen ser ut i staden i dagsläget samt sammanfattar de största källorna för organiskt avfall i Curitiba. Den årliga mängden organiskt avfall som produceras i staden uppskattas till 144 350 ton, varav 913 ton kommer från livsmedelsaktiviteter som övervakas av det brasilianska livsmedelsverket SMAB. Tre olika scenarier representeras i denna rapport och omfattar tre områden av avfallskällor. I det första scenariot behandlas det organiska avfallet som genereras av en av de två köpmarknaderna i Staden direkt på plats. I det andra behandlas allt organiskt avfall från livsmedelsmarknader, gatumarknader och populära restauranger tillsammans i en medelstor anaerob kokare. I det tredje beaktas alla källor till organiskt kommunalt avfall som identifierats i Curitiba, inklusive bostads-, institutionellt och litet kommersiellt avfall. Den årliga metanproduktionen uppskattas till 5 400 m3, 86 000 m3 respektive 12 600 000 m3 för de tre scenarierna. I det andra och tredje scenariot kunde metan omvandlas till el, vilket resulterade i en årlig elproduktion på 257 MWh respektive 37 600 MWh. I det första scenariot anses inte en efterbehandling av digestatet kvar vid slutet av matsmältningen. Mellan 46 och 50 ton digestat kan användas som flytande gödselmedel på plats och överskottet kan säljas. För de två andra scenarierna skulle digestatet avvattnas och komposteras för att senare säljas som torr gödsel vars produktion beräknas uppgå till 386 ton respektive 63 000 ton varje år. Alla tre scenario som presenteras i denna rapport anses vara ekonomiskt genomförbara med en diskonterad återbetalningstid som varierar mellan 8 månader för det första scenariot till över 15 år för det andra scenariot. Det tredje scenariot anses vara det mest lukrativa med ett nuvärde på ca 150 miljoner realer.

[pt] Esta tese tem por objetivo avaliar o potencial de geração de biogás, por degradação anaeróbica de resíduos sólidos urbanos em perfis de um aterro sanitário. As amostras foram obtidas a partir de perfis de sondagem compostos por materiais dispostos em épocas distintas e com diferentes idades em relação a seu estágio de decomposição. Foi elaborado protocolo específico para determinação da temperatura, pH, composição gravimétrica, distribuição granulométrica, teores de umidade, de matéria orgânica, de sólidos voláteis e de lignina nessas amostras e criada metodologia com o uso de dados topográficos, para a determinação das idades de disposição dos resíduos. Foi ainda desenvolvido equipamento eudiométrico para a determinação potencial bioquímico de metano, com medidas de variação volumétrica e avaliação do prognóstico de geração de metano por modelos de primeira ordem mais consagrados (LandGEM e IPCC). Os dados experimentais indicaram que poucas propriedades apresentaram uma correlação com o perfil e com a idade dos RSU, devido à alta heterogenidade do material. Embora o potencial de biogás e a idade dos RSU não tenham apresentado correlação entre si, o material mais novo, de quase um ano, produziu maior quantidade de biogás e houve uma redução de 78 porcento dessa produção para a do material de 3 anos. Verificou-se uma relação entre o teor de matéria orgânica e de sólidos voláteis com a produção de biogás para materiais com até 4 anos. O prognóstico da geração de biogás aplicando os dados experimentais aos modelos EPA e IPCC foi menor do que quando adotados os parâmetros default. A retroanálise segundo o IPCC, com os dados experimentais, indicaram valores de DOC muito inferiores aos usados com default, resultando em menores emissões de biogás. / [en] The aim of this thesis is to evaluate of the potential biogas generation formed in the anaerobic phase from the degradation of urban solid waste with variables ages of deposition in a sanitary landfill. The materials were obtained from borehole profiles, being composed of materials disposed at different times and with variables ages in relation to their state of deposition. The knowledge of the physic-chemical characteristics is essential for assessing the biochemical potential of gases. Thus, it was developed: (i) a protocol for determination of properties, such as temperature, pH, gravimetric composition, particle size distribution, moisture content, organic matter content, volatile solids content, lignin content; (ii) one eudiometer device was constructed, with volume variation measurements for determining the biochemical methane potential; (iii) methodology to identify the ages of waste disposal by topography; and (iv) a methodology for predicting methane generation by well-known first order models (LandGEM and IPCC). Due to the high heterogeneity of the material, the experimental data indicated that few properties showed a trend in their behavior with respect to the profile and the age of MSW. Although the potential for biogas generation and the age of MSW showed no correlation, the newer material (almost one year old) showed higher biogas production. Gas production related to the 3 year old material was 78 percent lower compared to the newer one. Even with limited data, there is a relationship between the content of organic matter and/or volatile solid matter with the production of biogas for materials with more than 4 years. The prediction of biogas generation by applying experimental data was lower compared to the results applying EPA and IPCC models. The backcalculation analysis with the experimental data determined of IPCC indicated much lower DOC values than those used with the default, resulting in lower emission of biogas.