<p> There is mounting pressure to find suitable disposal sites for both household and industrial waste in south-central Ontario as a solution to Metropolitan Toronto's growing 'garbage crisis'. New data indicate that the fine-grained glacial sediments of south-central Ontario, previously considered to be 'tight' and impermeable, are in fact penetrated by an extensive joint system. This thesis provides basic information regarding the regional character, orientation and origin of joints within the surficial glacial sediments and bedrock of south-central Ontario. Three regional joint sets can be identified. Within the bedrock, the joint sets are oriented northeast/southwest, northwest/southeast and north/south. This trend is consistent with the regional jointing pattern within the overlying glacial sediments and suggests that the joints may have propagated from the bedrock into the glacial sediments. A comparison between the regional jointing pattern identified in bedrock and glacial materials and the orientation of stress release structures suggests that the regional pattern of jointing is controlled by the regional stress field which results from intraplate tectonic stresses. However, the orientation of joints at any individual site may also be controlled by 'local' factors such as face orientation, direction of glacial ice movement and lithology and by randomly oriented joints formed as the result of physical and chemical weathering, synaeresis, subglacial deformation and stress relief. The identification of regional jointing pattern within south-central Ontario allows the prediction of joint characteristics and orientations at potential landfill sites in the region, critical to the accurate evaluation of the permeability of the substrate materials.</p> / Thesis / Master of Science (MSc)

O presente estudo aborda um caso de contaminação ambiental decorrente da operação de uma indústria de galvanoplastia e suas implicações na saúde da população de sua área de influência. A pesquisa foi desenvolvida através de um estudo de caso, com o objetivo de investigar a liberação de substâncias perigosas para o ambiente, avaliando o comprometimento atual e futuro da área exposta e da população local, visando identificar ações necessárias para analisar, mitigar e prevenir os riscos ao ambiente e à saúde pública. A metodologia utilizada para avaliar a contaminação ambiental e seus efeitos sobre a saúde baseou-se nos critérios de avaliação de saúde empregados pela Agency for Toxic Substances and Disease Registry-ATSDR, quando da investigação em áreas suspeitas de contaminação. Esta avaliação consiste no levantamento de dados ambientais, na identificação das preocupações da população exposta com o problema e dos efeitos potenciais sobre a saúde, visando a indicação, para o órgão ambiental competente, da necessidade de estudos ou ações de saúde pública mais aprofundados na área. Para tanto, foram efetuados levantamentos das informações disponíveis sobre a indústria e a caracterização sócio-ambiental da área; investigação das fontes de contaminação e de sua propagação; identificação da população exposta, das principais vias de exposição e dos efeitos potenciais dos contaminantes sobre a saúde. Os resultados obtidos confirmaram a presença de contaminantes emitidos pela indústria em todos os compartimentos ambientais pesquisados. Inicialmente supunha-se que o caso fosse resultante do lançamento de efluentes liquidos industriais fora dos padrões estabelecidos. Entretanto, a magnitude da contaminação indicou tratar-se de um caso bem mais grave, envolvendo a disposição inadequada de resíduos no solo e a referência à ocorrência de acidente industrial. Os principais efeitos identificados foram a contaminação das águas subterrâneas por poluentes químicos, a morte de dezenas de animais dos sítios vizinhos, a impossibilidade de utilização da área atingida para plantio ou criação de animais e os agravos à saúde referidos pela população, principalmente associados à ingestão das águas contaminadas. A situação encontrada tende a se agravar, devido à propagação da pluma de contaminantes nas águas subterrâneas, à incorporação dos poluentes no solo e sedimentos dos corpos d\'água, passíveis de serem liberados para o ambiente e, por outro lado, pelo atual crescimento da ocupação do núcleo residencial, que se estende ao longo da área contaminada. Com base no estudo realizado, recomenda-se uma investigação detalhada da área, com vistas à proposição e execução de medidas de remediação, tanto para a recuperação da área com o fim de se manter o uso atual da região como para a alteração de seu uso, buscando-se uma nova utilização compatível com a qualidade ambiental que venha a ser alcançada através da intervenção proposta. Recomenda-se ainda que as autoridades de meio ambiente e saúde pública efetivem ações no sentido de minimizar o risco da população exposta à área contaminada e à propagação da contaminação, monitorando a qualidade da fonte de abastecimento de água potável, fiscalizando o uso indevido de água do lençol freático, estabelecendo critérios para cultivos e criação de animais e propondo medidas para o isolamento das fontes de geração de contaminação remanescentes. / The present study approaches an environmental contamination case arising from an electroplating factory operation and its implications for the population living in the contaminated area. This research was developed as a study case to investigate the release of hazardous substances to the environment, assessing the current and future involvement of the exposed area and the local population in order to identify actions to analyze, mitigate and prevent damage to the environment and public health. The methodology to appraise environmental contamination and its effects on public health was based on the health evaluation criteria applied by ATSDR, whenever investigating probable areas of contamination. This evaluation consists of an environmental data survey, identifying the exposed population concerns about the problem and the potential effects on public health giving indication of the problem to the Department of Environmental Protection regarding the necessities for studies or deeper public health action within the area. Available information on industry and socio-economical characterization over the area such as investigation of sources of contamination and their propagation, identification of the exposed population from the ways of exposure and the potential effects of the contaminants on public health have been surveyed. The results indicated the presence of contaminants coming from the industry in all environmental effects surveyed. At first, the case was supposed to have resulted from industrial effluents not according to the required standards. Nevertheless the magnitude of the contamination proved to be a much more serious case involving inadequate disposal of solid waste in the soil and the reference to industrial accident occurrence. The main effects identified were contamination of the ground water by chemical pollutants, death of dozens of animais from the nearby little farms, impossibility of using the contaminated area to grow crops and raise animals, and the harmful effects to public health referred to by the population, mainly connected with contaminated water consumption. The situation encountered tends to get worse due to the spread of contaminated plume into the ground water, incorporation of pollutants in the soil and sediments of water collection which on one hand may be released to the environment, but on the other hand may extend along the contaminated area by the current increase of the residential nucleus occupation. Based on the this study, it is recommended that a detailed investigation of the area along with a proposal and carrying-out of the remediation measures not only for the recovery of the region to keep its present use, but also for its alteration searching for a new use of the area which could be compatible to an environmental quality reached by the intervention proposed. It is also recommended that public health and environmental protection authorities take measures to minimize the risk of human exposure to the contaminated area and the spread of the contamination by monitoring the quality of drinking water source supply, checking misuse of water arising from water bed, establishing criteria for cultivating and raising animais, and proposing measures to isolate the source of the remaining contamination.

O presente estudo aborda um caso de contaminação ambiental decorrente da operação de uma indústria de galvanoplastia e suas implicações na saúde da população de sua área de influência. A pesquisa foi desenvolvida através de um estudo de caso, com o objetivo de investigar a liberação de substâncias perigosas para o ambiente, avaliando o comprometimento atual e futuro da área exposta e da população local, visando identificar ações necessárias para analisar, mitigar e prevenir os riscos ao ambiente e à saúde pública. A metodologia utilizada para avaliar a contaminação ambiental e seus efeitos sobre a saúde baseou-se nos critérios de avaliação de saúde empregados pela Agency for Toxic Substances and Disease Registry-ATSDR, quando da investigação em áreas suspeitas de contaminação. Esta avaliação consiste no levantamento de dados ambientais, na identificação das preocupações da população exposta com o problema e dos efeitos potenciais sobre a saúde, visando a indicação, para o órgão ambiental competente, da necessidade de estudos ou ações de saúde pública mais aprofundados na área. Para tanto, foram efetuados levantamentos das informações disponíveis sobre a indústria e a caracterização sócio-ambiental da área; investigação das fontes de contaminação e de sua propagação; identificação da população exposta, das principais vias de exposição e dos efeitos potenciais dos contaminantes sobre a saúde. Os resultados obtidos confirmaram a presença de contaminantes emitidos pela indústria em todos os compartimentos ambientais pesquisados. Inicialmente supunha-se que o caso fosse resultante do lançamento de efluentes liquidos industriais fora dos padrões estabelecidos. Entretanto, a magnitude da contaminação indicou tratar-se de um caso bem mais grave, envolvendo a disposição inadequada de resíduos no solo e a referência à ocorrência de acidente industrial. Os principais efeitos identificados foram a contaminação das águas subterrâneas por poluentes químicos, a morte de dezenas de animais dos sítios vizinhos, a impossibilidade de utilização da área atingida para plantio ou criação de animais e os agravos à saúde referidos pela população, principalmente associados à ingestão das águas contaminadas. A situação encontrada tende a se agravar, devido à propagação da pluma de contaminantes nas águas subterrâneas, à incorporação dos poluentes no solo e sedimentos dos corpos d\'água, passíveis de serem liberados para o ambiente e, por outro lado, pelo atual crescimento da ocupação do núcleo residencial, que se estende ao longo da área contaminada. Com base no estudo realizado, recomenda-se uma investigação detalhada da área, com vistas à proposição e execução de medidas de remediação, tanto para a recuperação da área com o fim de se manter o uso atual da região como para a alteração de seu uso, buscando-se uma nova utilização compatível com a qualidade ambiental que venha a ser alcançada através da intervenção proposta. Recomenda-se ainda que as autoridades de meio ambiente e saúde pública efetivem ações no sentido de minimizar o risco da população exposta à área contaminada e à propagação da contaminação, monitorando a qualidade da fonte de abastecimento de água potável, fiscalizando o uso indevido de água do lençol freático, estabelecendo critérios para cultivos e criação de animais e propondo medidas para o isolamento das fontes de geração de contaminação remanescentes. / The present study approaches an environmental contamination case arising from an electroplating factory operation and its implications for the population living in the contaminated area. This research was developed as a study case to investigate the release of hazardous substances to the environment, assessing the current and future involvement of the exposed area and the local population in order to identify actions to analyze, mitigate and prevent damage to the environment and public health. The methodology to appraise environmental contamination and its effects on public health was based on the health evaluation criteria applied by ATSDR, whenever investigating probable areas of contamination. This evaluation consists of an environmental data survey, identifying the exposed population concerns about the problem and the potential effects on public health giving indication of the problem to the Department of Environmental Protection regarding the necessities for studies or deeper public health action within the area. Available information on industry and socio-economical characterization over the area such as investigation of sources of contamination and their propagation, identification of the exposed population from the ways of exposure and the potential effects of the contaminants on public health have been surveyed. The results indicated the presence of contaminants coming from the industry in all environmental effects surveyed. At first, the case was supposed to have resulted from industrial effluents not according to the required standards. Nevertheless the magnitude of the contamination proved to be a much more serious case involving inadequate disposal of solid waste in the soil and the reference to industrial accident occurrence. The main effects identified were contamination of the ground water by chemical pollutants, death of dozens of animais from the nearby little farms, impossibility of using the contaminated area to grow crops and raise animals, and the harmful effects to public health referred to by the population, mainly connected with contaminated water consumption. The situation encountered tends to get worse due to the spread of contaminated plume into the ground water, incorporation of pollutants in the soil and sediments of water collection which on one hand may be released to the environment, but on the other hand may extend along the contaminated area by the current increase of the residential nucleus occupation. Based on the this study, it is recommended that a detailed investigation of the area along with a proposal and carrying-out of the remediation measures not only for the recovery of the region to keep its present use, but also for its alteration searching for a new use of the area which could be compatible to an environmental quality reached by the intervention proposed. It is also recommended that public health and environmental protection authorities take measures to minimize the risk of human exposure to the contaminated area and the spread of the contamination by monitoring the quality of drinking water source supply, checking misuse of water arising from water bed, establishing criteria for cultivating and raising animais, and proposing measures to isolate the source of the remaining contamination.

The need for effective disposal of huge volumes of industrial waste is becoming more challenging due to expected imposition of stringent pollution control regulations in the near future. Thermochemical conversion, particularly gasification of organics in the waste is considered the best route from the perspective of volume reduction and prevalent eco-friendly concept of waste-to-energy transformation. It is considered imperative to have adequate understanding of basic combustion features as a part of the thermochemical conversion process, leading to gasification. The aim of this thesis is to understand the fundamental combustion processes associated with one of the top listed hazardous wastes from distilleries (Biochemical Oxygen Demand (BOD) ~ 40,000 - 50,000 mg/L), commonly known as vinasse, stillage or spent wash, through experiments and modeling efforts. Specially designed experiments on distillery effluent combustion and gasification are conducted in laboratory scale reactors. As an essential starting point of the studies on ignition and combustion of distillery effluent containing solids consisting of 62 ± 2 % organics and 38 ± 2 % inorganics (primarily sugarcane derivatives), the roles of solids concentration, drop size and ambient temperature were investigated through experiments on (1) liquid droplets of 65 % and 77 % solids (remaining water) and (2) spheres of dried effluent (100 % solids) of size 0.5 mm to 20 mm diameter combusted at ambient temperatures of 773 to 1273 K. The investigation reveals that the droplets burn with two distinct regimes of combustion, flaming and char glowing. The ignition delay ‘t1’ of the droplets increased with size as is in the case of non-volatile droplets, while that of bone-dry spheres was found to be independent of size. The ‘t1’ decreased with increase in solids concentration. The ignition delay has showed an Arrhenius dependence on temperature. The initial ignition of the droplets and the dry spheres led to either homogeneous (flaming) or heterogeneous (flameless) combustion, depending on the ambient temperature in the case of sphere and on solid concentration and the ambient temperature, in the case of liquid droplets. The weight loss during the flaming combustion was found to be 50 - 80 % while during the char glowing it was 10-20 % depending on the ambient temperature. The flaming time tc is observed as tc~ d2c , as in the case of liquid fuel droplets and wood spheres. The char glowing time tc' is observed as tc ~ d2c as in the case of wood char, though the inert content of effluent char is as large as 50 % compared to 2 - 3 % in wood char. In the case of initial flameless combustion, the char combustion rate is observed to be lower. The heterogeneous char combustion in quiescent air in controlled temperature conditions has been studied and modeled using one-dimensional, spherico-symmetric conservation equations and the model predicts most of the features of char combustion satisfactorily. The measured surface and core temperatures during char glowing typically are in the range of 200 to 400 K and are higher than the controlled temperature of the furnace. Based on the results of single droplet combustion studies, combustion experiments were conducted in a laboratory scale vertical reactor (throughput ranging from 4 to 10 g/s) with the primary aim of obtaining sustained combustion. Spray of effluents with 50 % and 60 % solids (calorific value 6.8 - 8.2 MJ/kg), achieved by an air blast atomizer, was injected into a hot oxidizing environment to determine the parameters (ambient temperature and air-fuel ratio) at which auto-ignition could occur and subsequently studies were continued to investigate pre-ignition, ignition and combustion processes. Effluent with lower solids concentration was considered first from the point of view of the less expensive evaporator required in the field conditions for concentration and a spin-off in terms of better atomization consequently. Three classes of experiments were conducted: 1) Effluent injection from the wall with no auxiliary heat input, 2) Effluent injection with auxiliary heat input and 3) effluent injection within kerosene enveloping flame. Though individual particles in the spray periphery were found to combust, sustained spray combustion was not achieved in any of the three sets of experiments even with fine atomization. While conducting the third class of experiments in an inclined metallic reactor, sustained combustion of the pool resulting of accumulated spray seemed to result in large conversion of carbon. This led to the adoption of a new concept for effluent combustion in which the residence time is controlled by varying reactor inclination and the regenerative heat transfer from the product gases supplies heat for endothermic pre-ignition process occurring on the bed. Combustion and gasification experiments were conducted in an inclined plate reactor with rectangular cross section (80 mm x 160 mm) and 3000 mm long. A support flame was found necessary in the injection zone in addition to the regenerative heat transfer. Effluent with 60% solids was injected as film on the reactor bed. This film disintegrated into fine particles due to induced aerodynamic stretching and shear stripping. Combustion of individual particles provided exothermic heat profile and resulted into high carbon conversion. However, effluent clogging in the cold injection zone hindered system from attaining steady state. Effluent injected directly on the hot zone caused it to remain mobile due to the spheroidal evaporation and thus assuaging this problem. Improved mass distribution was achieved by displacing nozzle laterally in a cycle, actuated by a mechanism. Consistent injection led to sustained effluent combustion with resulting carbon conversion in excess of 98 %. The typical gas fractions obtained during gasification condition (air ratio = 0.3) were CO2 = 14.0 %, CO = 7.0 %, H2 = 12.9 %, CH4 - 1 % H2S = 0.6 - 0.8 % and about 2 % of saturated moisture. This composition varied due to variation in temperature (± 30 K) and is attributed to combined effect of local flow variations, shifting zones of endothermic processes due to flowing of evaporating effluent over a large area. In order to minimize this problem, experiments were conducted by injecting effluent at higher solids (73 % solids is found injectable). The effluent was found to combust close to the injection location-due to the reduced ignition delay and lower endothermic evaporation load helped raising the local temperature. This caused the pyrolysis to occur in this hottest zone of the reactor with higher heating rates resulting in larger yield of devolatilized products and improved char conversion. Effluent combustion was found to sustain temperature in the reactor under sub-stoichiometric conditions without support of auxiliary heat input and achieved high carbon conversion. These results inspired the use of higher concentration effluent, which is also known in the case of wood to have improved gasification efficiency due to reduction in moisture fraction. In addition, the recent studies on the sulfur emission in the case of black liquor combustion in recovery boilers have revealed that with increase in solids concentration, release of sulfur in gas phase is reduces. The required concentration can be carried out using low-grade waste heat from the reactor itself. It was found through experiments that, even though spray ignition occurred at this concentration, the confined reactor space prevented the spray from attaining sustained combustion. This led to the conduct of experiments in a new vertical reactor with adequate thermal inertia, essential to prevent variations in local temperature to reach a steady state gasification and required space to accommodate the spray. The results of the experiments conducted in the vertical reactor in which effluents with 73 % solids, heated close to the boiling point and injected as fine spray in a top-down firing mode are consolidated and reported in the thesis in detail. Single particle combustion with enveloping faint flame was seen unlike stable flame found in coal water slurry spray combustion. Sustained gasification of gas-entrained particles occurred at reactor temperature in the range of 950 K - 1000 K and sub-stoichiometric air ratio 03 - 0.35 without the support of auxiliary fuel. The typical gas fractions obtained during gasification condition (air ratio = 0.3) were CO2 = 10.0 -11.5 %, CO - 10.0 - 12.0 %, H2 - 6.7 - 8.0 %, CH4 = 1.75 % H2S = 0.2 - 0.4 % and about 2 % of saturated moisture. The carbon conversion obtained was in the range of 95 - 96 %. These experiments have provided the conditions for gasification. The extraction of potassium salts (mostly sulfates, carbonate and chloride) from the ash, using a simple water leaching process, was found to recover these chemicals to as high an extent as 70 - 75 % of total ash. In summary it is concluded that increasing the solid concentrations to as high levels as acceptable to the system (~ 75 %) and introducing as a fine spray of heated material (~ 363 K) into furnace with air at sub-stoichiometric conditions in a counter current combustion reactor will provide the frame work for the design of a gasification system for vinasse and similar effluent material. The thesis consists of seven chapters. Chapter 1 introduces the problem and motivation of the work presented in the thesis. Literature review is presented in Chapter 2. The Chapter 3 deals with the single particle combustion studies. The results of effluent spray combustion experiments conducted in a laboratory scale vertical reactor are presented in Chapter 4. The results of combustion and gasification experiments conducted in another variant of a reactor, namely, inclined flat plate rectangular reactor is consolidated in Chapter 5. The results of gas-entrained spray gasification experiment of higher concentration effluent injected as spray in the vertical reactor are presented in Chapter 6. The general conclusions and scope for the future work are presented in the concluding chapter 7.