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Carbon Dioxide (CO2) is a major fermentation product generated during the production of beer, the subsequent release of this gas within the fermentor results in agitation that is necessary for sustained industrial fermentation. CO2 is sometimes monitored allowing brewers to stoichiometrically relate CO2 released to other products. In this manner the rate of gas release from the fermentor may be used to assess, control and predict other aspects of fermentation. The dynamics of CO2 generation, transport and release are explored throughout this thesis over several studies. The tools used to examine CO2 production were scrutinized including a miniature assay using various modeling techniques. A miniature scale fermentation assay included in the methods of the American Society of Brewing Chemists was compared to industrial scale fermentations. It was found that discrepancies were possibly due (at least in part) to fermentor geometry. Following this study, a literature review of CO2 solubility in aqueous sugar, and ethanol solutions was conducted. This study exposed previously undescribed inaccuracies in literature, i.e., it was found that several gas solubility tables were empirical derived and are therefore unlikely to accurately reflect all styles of beer. The next study scrutinized the consumption of sugars during barley fermentation and found that these fermentations often exhibit asymmetric sigmoidal attenuation. A five parameter logistic model was introduced to model this sugar consumption more accurately than previously described techniques. Using methods refined during the aforementioned studies, a fermentation was conducted where a mass balance was used to track all major fermentation parameters (the consumption of individual sugars, and the production of ethanol, carbon dioxide, yeast biomass and glycerol). This allowed an assessment of Balling’s theorem as compared to modern theory. It was shown that while accurate in predicting original extract, Balling’s theorem incorrectly quantified other fermentation parameters. This has large ramifications for both industry and research as the estimation of fermentation parameters (such as ethanol and fermentation time) is now better understood. From these studies, the production of beer becomes less of a “black box” operation, and CO2 saturation, transport and release can be better explained. Of the many fermentation aspects monitored during these studies, most were predicted by theory, however, there were notable exceptions. For instance, it was found that both the inhibition of maltose consumption and yeast sugar consumption dynamics (which remained relatively constant throughout the fermentation at ~ 50 pg·h-1 for cells with an average mass of ~ 40 pg). were found to deviate from previously described reports. These, and other findings improve our understanding of brewing fermentations allowing for additional applications of theory and recommendations in industrial operations.

The objective of this research is to develop a system capable of simulating snow depth and snow water equivalent in the Sherbrooke to Mount-Megantic area of Quebec's Eastern Townships using meteorological and digital terrain data as input.The working hypothesis is that meteorological data may drive a point energy and mass balance snow cover model.The model used was developed by the Hydrologic Research Lab (National Weather Service) which was calibrated for local conditions using field data collected during two winters at several sites on Mount-Megantic. Snow water equivalent and depth are used for calibration and validation of the model. Automated snow sensors were also used to obtain temperature calibration data.The snow surveys and correction of the air temperature for elevation improves the estimates of snow depth and water equivalent.The results suggest that data from the Sherbrooke meteorological stations can be used to estimate the snow cover over the area of Eastern Townships. Air temperature extrapolation across the field area is a challenge. However the simulated snow cover conforms generally well with data observed at several stations throughout the region.

Portland Cement pervious concrete's ability to permit water infiltration has encouraged its use as a stormwater management tool. However, the material has suffered historically poor support due to a number of factors, including failures due to poor mix design and improper construction techniques, concern about lesser structural strength, concern about poor long term performance due to clogging of surface pores and undefined credit for stormwater management. This study focuses on long term performances of pervious concrete parking lots and their stormwater management credit. Before stormwater management credit could be estimated, it was necessary to develop a testing device to gather information from existing pervious concrete parking lots currently in use. Eight parking lots were examined to determine the infiltration rates of the pervious concrete, as well as to verify the soil makeup beneath pavement. A total of 30 cores were extracted from pervious concrete parking lots and evaluated for infiltration rates. Three of the sites had a pervious concrete section that included a gravel reservoir. Infiltration rates were measured using the application of an embedded single-ring infiltrometer. In an attempt to provide an estimate of credit, a mass balance model was created to be used for simulation of the hydrologic and hydraulic function of pervious concrete sections. The purpose of the model is to predict runoff and recharge volumes for different rainfall conditions and hydraulic properties of the concrete and the soil. The field derived hydraulic data were used to simulate infiltration volumes and rainfall excess given a year of rainfall as used in a mass balance operated within a spreadsheet. The results can be used for assessing stormwater management credit.

Ce mémoire a comme objectif de présenter une revue de la littérature et une analyse comparative des différents modèles existants pour le calcul de la capacité de support d’un plan d’eau aux apports en phosphore. Ce document a aussi pour but d’évaluer les différentes options pour l’utilisation de ce genre d’outil au Québec, ainsi que d’amorcer une réflexion sur les applications possibles de ce concept au niveau local, en lien avec l’aménagement du territoire des bassins versants. L’analyse comparative des modèles théoriques, combinée à la réflexion d’acteurs clés impliqués actuellement dans un processus qui consiste à tester leur utilisation dans les Laurentides au Québec, a permis de mettre en relief l’importance de calibrer les modèles régionalement. De plus, certains avantages semblent résider dans l’utilisation d’un modèle de nature empirique afin d’effectuer les prédictions sur les apports naturels et totaux en phosphore pour les lacs de cette région. Par contre, l’utilisation d’une approche de type « bilan de masse », s’avère tout de même indispensable afin de relativiser l’importance des différents apports anthropiques en phosphore du bassin versant. Dans l’avenir, l’utilisation de tels modèles permettra possiblement de justifier certaines mesures restrictives au développement des bassins versants, qui pourront s’insérer parmi les outils d’urbanisme actuels. Ce sont principalement les municipalités qui détiennent les pouvoirs nécessaires afin d’intégrer les prescriptions découlant de ce genre d’analyse à l’aménagement du territoire des bassins versants. Plusieurs outils d’urbanisme, tels que les plans d’aménagement d’ensemble (PAE) ou bien les règlements de zonage et de lotissement, semblent donner assez de latitude afin de permettre aux municipalités d’intervenir en ce sens. Toutefois, les modèles de capacité de support ne pourront pas être utilisés afin de calculer un nombre précis d’habitations qu’il est possible de construire dans le bassin versant d’un lac. / This study presents a literature review of current carrying capacity models developed in Ontario and Quebec (Canada) for the estimation of phosphorus (P) loading in lakes. Another objective is to evaluate their applications to land and watershed management practices in Quebec. A comparison of theoretical and empirical models, combined with the observations of keys stakeholders, confirms the importance of calibrating models regionally. The analysis further reveals that empirical models estimate more accurately P concentrations in lakes. However, the use of traditional mass balance approaches is still a necessity for the estimation of different P sources in the watershed. These models can support decision makers and land managers in Quebec in the application of more restrictive measures in lakes where the carrying capacity is currently exceeded. In Quebec, the use of the models and their implementation in the legislation will be a municipal responsibility. Many urbanism tools already allow this kind of intervention (zoning, « outils à caractère discrétionnaire »). But, model use alone will not be sufficient to justify a total interdiction of land development in a watershed or to impose a strict limit to house and cottage development.

Ce mémoire a comme objectif de présenter une revue de la littérature et une analyse comparative des différents modèles existants pour le calcul de la capacité de support d’un plan d’eau aux apports en phosphore. Ce document a aussi pour but d’évaluer les différentes options pour l’utilisation de ce genre d’outil au Québec, ainsi que d’amorcer une réflexion sur les applications possibles de ce concept au niveau local, en lien avec l’aménagement du territoire des bassins versants. L’analyse comparative des modèles théoriques, combinée à la réflexion d’acteurs clés impliqués actuellement dans un processus qui consiste à tester leur utilisation dans les Laurentides au Québec, a permis de mettre en relief l’importance de calibrer les modèles régionalement. De plus, certains avantages semblent résider dans l’utilisation d’un modèle de nature empirique afin d’effectuer les prédictions sur les apports naturels et totaux en phosphore pour les lacs de cette région. Par contre, l’utilisation d’une approche de type « bilan de masse », s’avère tout de même indispensable afin de relativiser l’importance des différents apports anthropiques en phosphore du bassin versant. Dans l’avenir, l’utilisation de tels modèles permettra possiblement de justifier certaines mesures restrictives au développement des bassins versants, qui pourront s’insérer parmi les outils d’urbanisme actuels. Ce sont principalement les municipalités qui détiennent les pouvoirs nécessaires afin d’intégrer les prescriptions découlant de ce genre d’analyse à l’aménagement du territoire des bassins versants. Plusieurs outils d’urbanisme, tels que les plans d’aménagement d’ensemble (PAE) ou bien les règlements de zonage et de lotissement, semblent donner assez de latitude afin de permettre aux municipalités d’intervenir en ce sens. Toutefois, les modèles de capacité de support ne pourront pas être utilisés afin de calculer un nombre précis d’habitations qu’il est possible de construire dans le bassin versant d’un lac. / This study presents a literature review of current carrying capacity models developed in Ontario and Quebec (Canada) for the estimation of phosphorus (P) loading in lakes. Another objective is to evaluate their applications to land and watershed management practices in Quebec. A comparison of theoretical and empirical models, combined with the observations of keys stakeholders, confirms the importance of calibrating models regionally. The analysis further reveals that empirical models estimate more accurately P concentrations in lakes. However, the use of traditional mass balance approaches is still a necessity for the estimation of different P sources in the watershed. These models can support decision makers and land managers in Quebec in the application of more restrictive measures in lakes where the carrying capacity is currently exceeded. In Quebec, the use of the models and their implementation in the legislation will be a municipal responsibility. Many urbanism tools already allow this kind of intervention (zoning, « outils à caractère discrétionnaire »). But, model use alone will not be sufficient to justify a total interdiction of land development in a watershed or to impose a strict limit to house and cottage development.

This thesis focused on the modelling of a pulping process. The purpose was to see if an accurate model can be crated based on relatively simple premises and if the errors can be identified or analysed. To realise this, the authors conducted a literature study to identify the current state of the art regarding the chemical pulping process. In addition, flow charts and sample data from a case study were examined. Based on the literature review and case study, model assumptions were derived. The model is divided into sixteen components. Where mixing occurs, lumped conditions are assumed. The model has five validation points, four of which are temperatures and a mass flowrate. These are shown as deviations from the measured values. In conclusions, it was the model could produce stable results over a narrow time frame. More so if the transition period at the start of the simulation is overlooked. Several new model assumptions are presented with the purpose to increase accuracy e.g. account for the components ability to store mass.

[pt] O mercúrio usado no garimpo do ouro na região amazônica é liberado para a atmosfera, solo e rios. Uma vez na atmosfera, o metal é oxidado e imediatamente se deposita. Na água, ocorre a transformação para o metilmercúrio principalmente pela ação de microrganismos. A formação do metilmercúrio aumenta a dispersão e biodisponibilidade do elemento no ambiente aquático. O metilmercúrio pode ser incorporado pelo plancton entrando, assim, na cadeia alimentar. A concentração do metal aumenta a medida que se ascende nos níveis tróficos da cadeia, atingindo os valores mais elevados em peixes carnívoros como o tucunaré. Dessa forma, as emissões de mercúrio provocam a contaminação dos recursos naturais e aumentam os riscos para a saúde dos consumidores habituais de pescado. O objetivo deste trabalho é testar um modelo de bioacumulação de mercúrio em peixes para estimar concentrações em predadores de topo da cadeia alimentar. O modelo pode ser usado como ferramenta para a gestão ambiental de ecossistemas aquáticos potencialmente contaminados com mercúrio. Este objetivo foi atingido através da combinação dos modelos de balanço de massa de Trudel e bioenergético de Wisconsin, aplicados em espécies tropicais do gênero Cichla (tucunaré) da bacia do rio Tapajós. O modelo bioenergético de Wisconsin foi usado para determinar as taxas de consumo de alimento a partir de dados de crescimento estimados. Os parâmetros usados nos modelos foram obtidos na literatura. A habilidade da modelagem na predição dos teores de mercúrio em tucunarés foi avaliada através da comparação com dados de campo obtidos nos anos 1992 e 2001, no rio Tapajós e no sistema de lagos Maicá. Os melhores resultados foram alcançados para os espécimes coletados no ano 1992, o que parece estar relacionado com uma melhor estimativa da concentração de mercúrio no alimento neste ano. / [en] The mercury used in the artisanal mining (garimpo) of gold in the Amazon region is emitted to the atmosphere, soil and rivers. Once in the atmosphere, the metal is oxidized and immediately deposited. In the water, the transformation to methylmercury takes place mostly due to the action of microorganisms. The formation of methylmercury increases the dispersion and bioavailability of the element in the aquatic environment. The methylmercury can be assimilated by the plankton and enters the food chain. The concentration of the metal increases further up in the trophic levels of the chain and reaches the highest values in carnivorous fishes like tucunaré. Thus, the mercury emissions cause the contamination of natural resources and enhance the risks to the health of regular fish consumers. The objective of this work is to test a model for bioaccumulation of mercury in fishes. The model calculates concentrations in top predators of the food chain and can be used as a tool for the management of aquatic ecosystems potentially contaminated with mercury. This objective was accomplished through the combination of the Trudel mass balance and Wisconsin bioenergetics models, applied to tropical species of the Cichla (tucunaré) genre of the Tapajós river basin. The Wisconsin bioenergetics model was utilized to determine the rates of food consumption from estimated fish growth data. The parameters used in the models were found in the literature. The ability of the models to predict mercury contents in tucunarés was evaluated by comparison with the field data, obtained in 1992 and 2001, in the Tapajós River and in the Maicá lakes. The best results were attain ed for specimens collected in 1992 what seems to be related to a better estimate of mercury concentration in the food in this year.

[pt] Os modelos de balanço de massa servem como ferramenta para compreender e/ou quantificar o comportamento e destino de compostos químicos no meio ambiente, através dos diferentes compartimentos ambientais. Estes têm como finalidade principal a obtenção de um panorama geral e observação das conexões entre diversos fatores que impactam na concentração, no transporte e na transformação de compostos químicos. A Lagoa Rodrigo de Freitas e o Complexo Lagunar de Jacarepaguá, no Rio de Janeiro, são regiões costeiras que funcionam como bacias de acumulação sofrendo constantemente com problemas relacionados à poluição, por estarem situadas em regiões de alta urbanização, densidade demográfica e fluxo de veículos. Trabalhos de monitoramento realizados nas regiões apontam que as lagoas apresentam concentrações elevadas de metais, que quando liberados no meio ambiente tendem a se distribuir e acumular em diferentes compartimentos, bióticos e abióticos. Estes contaminantes apresentam persistência ambiental, estão frequentemente biodisponíveis no compartimento aquático e muitas vezes levam a efeitos tóxicos, tanto para a biota exposta quanto para os humanos. Todavia algumas regiões são de difícil monitoramento devido a questões logísticas e financeiras, e o uso desse tipo de modelagem vêm sendo empregada como uma ferramenta interessante. Neste contexto, o presente trabalho descreve os resultados da modelagem ambiental, tendo a aquivalência como critério de equilíbrio, na análise do destino e transporte de diferentes metais nas duas regiões supracitadas, através da estimativa e discussão das taxas de fluxos, regiões de acúmulo, variações locais e graus de complexidade dos modelos. Os resultados indicam que, em ambos os casos, houve um bom ajuste dos modelos para a realidade local. Na Lagoa Rodrigo de Freitas a maior remoção de metais ocorreu através do ar (89,88 por cento). Água e sedimento (49,11 por cento) foram as regiões que mais trocaram metais, sendo também a poeira urbana uma importante fonte de troca. Sedimento, poeira urbana e emissões diretas no meio aquático contribuíram mais significativamente para o transporte de metais para a água (maior 75 por cento). Na Lagoa de Jacarepaguá a maior remoção de metais ocorreu através do ar (49,36 por cento) e soterramento (28,42 por cento). A advecção do ar (49,39 por cento) e da água (44,68 por cento) foram as maiores vias de remoção de metais na Lagoa da Tijuca, enquanto na Lagoa de Marapendi a remoção se deu quase exclusivamente através da advecção no ar. A advecção da água e o sedimento foram as principais fontes de metais para as águas das Lagoas de Jacarepaguá e Tijuca, enquanto o ar foi o responsável por grande parte desse aporte na Lagoa de Marapendi, sendo justificado pela configuração espacial das lagoas e as premissas adotadas no modelo. As regiões com maior tendência de acúmulo de metais foram o sedimento, o solo e a poeira urbana. O maior grau de complexidade do modelo em comparação a um modelo mais simplificado e a maior quantidade/confiabilidade dos dados ambientais aumentaram a precisão das predições do modelo. Estes resultados certificam o uso desse tipo de modelagem como ferramenta auxiliar no controle, classificação e avaliação de risco e tomada de decisões pelos órgãos competentes. / [en] Mass balance models serve as a tool to understand and/or quantify the behavior and fate of chemical compounds in the environment, across different environmental compartments. These have as main purpose to obtain an overview and observation of the connections between different factors that impact the concentration, transport, and transformation of chemical compounds. The Rodrigo de Freitas lagoon and the Jacarepaguá lagoonal complex, in Rio de Janeiro, are coastal regions that function as accumulation basins, constantly suffering from problems related to pollution, as they are located in regions of high urbanization, demographic density and vehicles flow. Monitoring work carried out in the regions indicates that the lagoons have high concentrations of metals, which when released into the environment tend to be distributed and accumulated in different compartments, biotic and abiotic. These contaminants have environmental persistence, are often bioavailable in the aquatic compartment, and often lead to toxic effects, both for exposed biota and for humans. However, some regions are difficult to monitor due to logistical and financial issues, and the use of this type of modeling has been used as an interesting tool. In this context, the present work describes the results of the environmental modeling, having aquivalence as a balance criterion, in the analysis of the destination and transport of different metals in the two aforementioned regions, through the estimation and discussion of the flow rates, accumulation regions, local variations and degrees of complexity of the models. The results indicate that, in both cases, there was a good adjustment of the models to the local reality. In Rodrigo de Freitas lagoon, the highest removal of metals occurred through air (89.88 per cent). Water and sediment (49.11 per cent) were the regions that most exchanged metals, with road dust also being and important source of exchange. Sediment, road dust, and direct emissions into aquatic environment contributed most significantly to the transport of metals into water (more than 75 per cent). In the Jacarepaguá lagoon, the highest metal removal occurred through air (49.36 per cent) and burial (28.42 per cent). Air (49.39 per cent) and water (44.68 per cent) advection were the major means of metal removal in the Tijuca lagoon, while in the Marapendi lagoon removal occurred almost exclusively through air advection. The advection in water and sediment were the main sources of metals for the waters of the Jacarepaguá and Tijuca lagoons, while the air was responsible for a large part of this contribution in the Marapendi lagoon, being justified by the spatial configuration of the lagoons and the assumptions adopted in the model. The regions with the greatest tendency for metal accumulation were sediment, soil and road dust. The greater degree of complexity of the model compared to a more simplified model and the greater quantity/reliability of the environmental data increased the accuracy of the model s predictions. These results certify the use of this type of modeling as an auxiliary tool in the control, classification and risk assessment, and decision-making by the competent agencies.

<p>This report is commissioned by the Water and Sewage Agency in The City of Mariehamn, Åland. The basic aim is to investigate positive or negative effects of a relocation of the sewage pipe from a wastewater treatment plant, Lotsbroverket. The environmental licence of Lotsbroverket is to be revised and The Environmental Appeal Board at Åland’s Government and Administrative Board has made demands that several possible locations in an outer water area should be examined. The present location of the sewage pipe is in Svibyviken, which has been classified as an “inner water area”.</p><p>The objective of this work is to study to which extent the nutrient loading from Lotsbroverket influence the environmental conditions in Svibyviken, and to investigate the suitability of different locations of the wastewater pipe from Lotsbroverket.</p><p>The way a coastal area looks, i.e., its morphometry, determines to a large extent its ecological characteristics. The investigated coastal area was digitalized from a nautical chart. The software used for this was Roots 3.3 and the GIS-tool ArcGIS 8.3. The localization of the coastal boundaries for the entire coastal area and for investigated sub-areas was determined according to the topographical bottleneck method, i.e., the boundary lines were drawn where the exposure of the coast to the open sea is minimized.</p><p>A process-based dynamic mass-balance model for total phosphorous has been used in this study. Using this model, one can estimate and quantify the effects of different nutrient sources in coastal areas. All the fluxes of phosphorous to, from and within the defined areas were studied and ranked. Model simulations have shown how changes in any of the phosphorous fluxes influence the mean monthly concentrations of total phosphorous. The situation for total nitrogen was determined with a statistical/empirical regression model between phosphorous and nitrogen concentrations. To estimate the expected ecological effects from a change in the nutrient loading from Lotsbroverket, statistical/empirical correlations between modelled nutrient concentrations and ecological effect variables have been used. Standard effect variables for the study of eutrophication effects in coastal areas are, e.g., the chlorophyll concentration, Secchi depth and oxygen saturation in deep water. These variables have also been used in this study.</p><p>It has been shown that (1) the nutrient concentrations of the Baltic Sea controls the concentration of nutrients in the studied areas to a very large extent, (2) that the nutrient fluxes from Lotsbroverket are small compared to the nutrient fluxes from the Baltic Sea and hence also of minor importance for the nutrient state of the receiving water system, (3) that the influence of the nutrient emissions from Lotsbroverket are most noticeable in the present inner recipient, Svibyviken, and (4) that the impact logically decreases with distance between the location of the sewage pipe and boundary line to the open sea. The overall conclusion is that no major improvement of the conditions in Svibyviken can be expected by a reduction or a relocation of the nutrient emissions from Lotsbroverket.</p> / <p>Detta examensarbete är ett uppdrag av VA-verket vid Mariehamns stad, Åland, med syfte att utreda effekter av en eventuell flyttning av avloppsreningsverket Lotsbroverkets utloppsledning. Inför en revidering av Lotsbroverkets miljötillstånd har Miljöprövningsnämnden vid Ålands landskapsregering ställt villkor på att tillståndshavaren skall utreda möjligheter till att avleda det renade avloppsvattnet till ett yttre vattenområde. Utloppsledningen mynnar i dagsläget i Svibyviken, vilken har klassificerats som ett inre vattenområde.</p><p>Målsättningen med detta arbete är att belysa vilka ekologiska effekter näringsämnesutsläppet från Lotsbroverket har på primärrecipienten Svibyviken samt att undersöka några andra områdens lämplighet som mottagare av avloppsvattnet. Ett kustområdes utseende och form, det vill säga dess morfometri, avgör i stor utsträckning dess ekologiska förhållanden. För att få en god bild av det undersökta områdets morfometri digitaliserades området utifrån ett sjökort i digitaliseringsprogrammet Roots 3.3, varefter data bearbetades med GIS-verktyget ArcGIS 8.3. Avgränsning av kustområdet som helhet och av undersökta delområden gjordes enligt den topografiska flaskhalsmetoden, det vill säga så att kustens öppenhet mot utanförliggande hav eller vattenområde minimeras (Håkanson et al., 1984; Pilesjö et al., 1991).</p><p>För arbetet har en processbaserad, dynamisk massbalansmodell för totalfosfor använts. Modellen har tagits fram för att eutrofieringseffekter i kustområden skall kunna studeras (Håkanson & Karlsson, 2001). Vid användandet av modellen kan effekter av olika näringsämneskällor uppskattas och kvantifieras. Samtliga totalfosforflöden till, från och inom olika avgränsade områden har studerats och rangordnats. Modellsimuleringar har visat hur förändringar i något av fosfortillflödena inverkar på recipientens månadsmedelkoncentration av totalfosfor. Situationen för kväve har undersökts med hjälp av en statistisk/empirisk regressionsmodell mellan fosfor- och kvävehalt. För att belysa de ekologiska effekter som kan förväntas efter en förändring av Lotsbroverkets fosfor- och kväveutsläpp har statistiska/empiriska kopplingar gjorts mellan näringsämneskoncentrationer och ekologiska effektvariabler. Bra effektvariabler vid undersökning av eutrofieringseffekter är exempelvis klorofyllhalt, siktdjup samt syrgashalt i bottenvattnet. Dessa variabler har också använts i detta arbete.</p><p>Resultaten visar att (1) närsaltskoncentrationerna i de studerade områdena i hög grad styrs av den allmänna eutrofieringsnivån i Östersjön, (2) att utsläppet av näringsämnen från Lotsbroverket inte inverkar på recipientens näringsstatus i någon stor utsträckning, (3) att Lotsbroverkets påverkan är störst på nuvarande recipient, Svibyviken, (4) och att påverkan sedan successivt minskar ju längre ut mot öppna havet utloppsledningen lokaliseras. Slutsatsen av utredningen är att en reduktion av Lotsbroverkets utsläpp eller nylokalisering av utloppsledningen inte kan förväntas ge någon omfattande förbättring av tillståndet i Svibyviken.</p>