Made available in DSpace on 2017-06-01T18:20:26Z (GMT). No. of bitstreams: 1 dissertacao_micheline_oliveira.pdf: 816714 bytes, checksum: 7522d63bc0d2083d9c31fe1f30d928f5 (MD5) Previous issue date: 2009-03-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The first step of the present work was characterizing a dairy effluent in terms microbiological and physical-chemical used to obtain a microbial consortium for its biodegradation. Microbiological characterization was performed by total heterotrophic bacteria, filamentous fungi and yeasts count according to the official methodologies. Physical-chemical characterization was accomplished by content of protein, ash, lipids, carbohydrates, pH and chemical oxygen demand (COD). Microbial consortium was obtained in batch using a bioreactor containing 1,5L of dairy effluent, at 200 rpm, 1vvm, at 28 - 30oC. Cultivations were performed in duplicate for eleven days, being applied a pulse of 10% (v/v) of effluent on the seventh day of the experiment. Cellular growth kinetics, chemical oxygen demand concentration and lipolytic activity were determined. Initial concentrations of bacteria and fungi and yeasts were equal to 3x109CFU/mL and 8x104CFU/mL, respectively. Effluent presented a COD of 64.000mgO2/L, pH 5,0 and concentrations of 5g/100mL of carbohydrates, 0,8g/100mL of protein and 0,6g/100mL of lipids. Cultivations showed an increase on the bacteria concentration, reaching 1x1013CFU/mL after eight days, while filamentous fungi and yeast concentrations were inhibited. An reduction of COD concentration in the range of 47 to 63,5% was observed after eleven days of cultivation, demonstrating the potentiality of use of microbial consortium for effluent treatment. Qualitative assays showed the presence of the enzymes lipase, amylase, protease and cellulase in the metabolic extract of the microbial consortium. However, low values of lipolytic activity were obtained as compared to the commercial enzyme, being observed that activity decreases along time. In the second step of this study, was evaluated the enzymatic hydrolysis of floated material, obtained from the column flotation of a dairy industry, using the technique of experimental design. Initially, performance was evaluated by a commercial lipase (lipolase®), being investigated the effects of agitation and enzyme concentration on hydrolysis. A statistical analysis was performed considering the significance of effects to a confidence level of 95%. Higher enzyme concentrations in the range investigated (1 to 7%) maximize the hydrolysis of oils and fats in the floated material, and to agitation levels between 100 and 150rpm. In all experiments, fatty acids were released in rates near to 100% only after 4 hours of reaction. Moreover, rates of released fatty acids were greater than 92% in all the concentration range tested. An agitation of 150rpm was used in a second experimental design, evaluating the concentration of commercial enzyme associated with a microbial consortium. The kinetic monitoring of the process showed that the addition of the consortium did not influence in a positive manner the increase the content of free fatty acids. / A primeira etapa do presente trabalho consistiu em caracterizar um efluente lácteo industrial (soro de queijo) em termos microbiológicos e físico-químicos visando à obtenção de um consórcio de microrganismos para a sua biodegradação. Foram determinadas a contagem padrão de bactérias heterotróficas e a contagem de fungos filamentosos e leveduras de acordo com as metodologias oficiais, e a caracterização físico-química foi realizada em termos do teor de proteínas, cinzas, lipídios, carboidratos, pH e demanda química de oxigênio (DQO). O consórcio microbiano foi obtido em biorreator operando em batelada e contendo 1,5L do efluente, a 200rpm, aeração de 1vvm e temperatura de 28 - 30oC. Os cultivos foram realizados em duplicata durante onze dias, sendo realizado um pulso de 150mL do efluente (10% do volume útil do biorreator) no sétimo dia do cultivo. Foram obtidas concentrações iniciais de 3x109UFC/mL e 8x104UFC/mL para contagem total de bactérias e de fungos e leveduras, respectivamente. O efluente apresentou uma DQO inicial de 64.000mgO2/L, pH 5,0, e concentrações correspondentes a 5g/100mL de carboidratos, 0,8g/100 mL de proteínas e 0,6g/100 mL de lipídios. Os cultivos do efluente no biorreator demonstraram um aumento da concentração de bactérias ao longo do tempo, atingindo 1x1013UFC/mL após oito dias, enquanto que as concentrações de fungos filamentosos e de leveduras foram inibidas. Foi observada uma redução da DQO de 47 a 63,5% após 11 dias de cultivo, demonstrando a potencialidade da utilização do consórcio microbiano no tratamento do efluente. Ensaios qualitativos demonstraram a presença das enzimas: lipase, amilase, protease e celulase no extrato metabólito do consórcio microbiano. No entanto, foram obtidos baixos valores de atividade lipolítica quando comparados com a atividade da enzima comercial, sendo observado ainda que a atividade decresce ao longo do tempo. Na segunda etapa do trabalho foi avaliada a hidrólise enzimática de material flotado, obtido a partir do processo de flotação em coluna do efluente, utilizando a técnica de planejamento de experimentos. Inicialmente, foi avaliado o desempenho de uma lipase comercial (lipolase®), sendo investigados os efeitos da agitação e da concentração de enzima sobre a hidrólise. Foi realizada a análise estatística considerando os efeitos significativos para um nível de confiança de 95%. Concentrações maiores de enzima dentro da faixa investigada (1 a 7%) maximizam a hidrólise de óleos e gorduras do material flotado, bem como para níveis de agitação entre 100 e 150rpm. Em todos os experimentos houve a liberação de ácidos graxos no meio em percentuais próximos a 100% apenas após 4 horas de reação. Vale salientar ainda que percentuais de liberação de ácidos graxos superiores a 92% foram obtidos para toda a faixa de concentração testada. Uma agitação de 150rpm foi utilizada em um segundo planejamento experimental, avaliando-se a concentração da enzima comercial associada a um consórcio microbiano, sendo verificado que a adição do consórcio não influenciou de maneira positiva o aumento do teor de ácidos graxos livres no meio.

Made available in DSpace on 2017-06-01T18:20:29Z (GMT). No. of bitstreams: 1 dissertacao_luiz_queiroz.pdf: 1547317 bytes, checksum: 857e36c6f9b83aa7f85250f7a37ba4ec (MD5) Previous issue date: 2010-06-17 / The coastal zone of Pernambuco comprises a range of 187 km and covers 21 cities. It presents the greatest agglomeration of the state, which concentrates approximately 44% of the population. Overfishing and pollution environment, coupled with global climate change will lead to a collapse of all fish in 2048. These environmental impacts change the concentration or the distribution of nitrogen, phosphorus and silicon (limiting production primary). It also interferes in their biogeochemical cycles. The application of numerical models in coastal areas may indicate a better estimate of nutrient fluxes associated with their transfer and geochemistry consequence. The objective of this study was to estimate concentrations of the major nutrients:nitrogen, phosphorus and silicon through mathematical modeling. In the methodology it was used the data Program REVIZEE, collected by the Department of Oceanography (UFPE) in the summer of 1997. The estimates of concentrations of nitrogen, phosphorus and silicon from the sea coast in the state of Pernambuco generated information to support the future activities of fishing. The scientific support for the increased demand of fishing is related to the economic production of the coastal area region / A zona costeira de Pernambuco compreende uma faixa de 187 km de extensão e abrange 21 municípios. Apresenta o maior aglomerado populacional do Estado, onde está concentrada aproximadamente 44 % da população. Pesca intensiva e poluição ambiental, aliadas a uma mudança de clima global conduzirão a um colapso de todos os pescados em 2048. Esses impactos ambientais alteram a concentração ou distribuição de nitrogênio, fósforo e silício (biolimitantes da produção primária) e interferem em seus ciclos biogeoquímicos. A aplicação de modelos numéricos a zonas costeiras pode indicar uma previsão melhor dos fluxos de nutrientes associados com suas transferências e conseqüência geoquímica. O objetivo deste trabalho foi estimar concentrações dos principais nutrientes dissolvidos: nitrogênio, fósforo e silício através de modelagem matemática. Na metodologia foram utilizados dados do Programa REVIZEE, coletados pelo Departamento de Oceanografia (UFPE) no verão pernambucano de 1997. As estimativas das concentrações dos nutrientes nitrogênio, fósforo e silício da costa marinha no estado de Pernambuco geram informações que dão suporte à atividades futuras de pesca artesanal. O apoio científico serve de suporte para o aumento da demanda pesqueira que é de produção econômica para a região, considerando ser a mesma uma zona costeira

Made available in DSpace on 2017-06-01T18:20:30Z (GMT). No. of bitstreams: 1 dissertaca-_marcelo_silva.pdf: 974611 bytes, checksum: 8bf2b65106d8d1d7d04ec3c0dd5827f6 (MD5) Previous issue date: 2011-03-17 / The production of protease and biosurfactant by Bacillus licheniformis UCP-1014 was investigated in this work. The experiments were performed in Erlenmeyer flasks, in triplicate, and inoculum 10% v/v, 150 rpm and 37ºC. A factorial design was conducted to investigate the concentrations of the medium. Metabolic fluid samples were collected, centrifuged and the supernatant used to determine pH, proteolytic activity and surface tension. The liquid was concentrated by ultrafiltration metabolic the stability and proteolytic activity in the retentate was determined for pH and temperature. In making the retentate was used a factorial design, and protease stability was determined during 10, 20 and 30 days at 28ºC. The determination of protease was performed in the presence of azo-casein. The culture of B.licheniformis UCP-1014 produced 112 U/mL protease in the presence of 1% molasses and urea 0,5%, pH 7,5 at 24h of culture. The reduction in surface tension was not significant in these metabolic conditions. The concentration of proteases produced by B. licheniformis UCP-1014 had the highest stability of enzyme activity in the absence of substrate at pH 7 during 60 min of incubation and maximum thermal stability between 40 90ºC for 90 min. The liquid concentrate and formulated metabolic retained about 50% of proteolytic activity whose value decreased during storage at 28ºC. Proteases produced by B. licheniformis UCP-1014 in the presence of nutrients of low cost can be competitive in the market / A produção de proteases e biossurfactantes por Bacillus licheniformis UCP-1014 foi investigada neste trabalho. Os experimentos foram realizados em frascos de Erlenmeyer de 125 mL, em triplicata, inóculo 10% v/v, a 150 rpm e 37ºC. Um planejamento fatorial foi realizado para investigar as concentrações dos componentes do meio de cultivo. Amostras de líquido metabólico foram coletadas, centrifugadas e os sobrenadantes utilizados para determinar pH, atividade proteolítica e tensão superficial. O líquido metabólico foi concentrado por ultrafiltração e a estabilidade da atividade proteolítica no retentado foi determinada quanto ao pH e à temperatura. A estabilidade do retentado foi investigada por planejamento fatorial e a atividade proteolítica determinada com 10, 20 e 30 dias de armazenamento a 28 ºC. A determinação de proteases foi realizada na presença de azo-caseína. A cultura de B. licheniformis UCP-1014 produziu 112 U/mL de proteases na presença de melaço 1% e uréia 0,5%, a pH 7,5 com 24 h de cultivo. A redução da tensão superficial do líquido metabólico não foi significativa nessas condições de trabalho. O líquido metabólico concentrado reteve cerca de 50% da atividade proteolítica inicial. O concentrado de proteases apresentou a maior atividade enzimática em pH 8 durante 30 min de incubação, retendo 97 % da atividade; a estabilidade térmica máxima foi a 50ºC durante 30 min, retendo 98 % da atividade enzimática. O retentado do líquido metabólico após formulado manteve 54 % da atividade com 30 dias de armazenamento a 28ºC. Proteases produzidas por B. licheniformis UCP-1014 na presença de nutrientes de baixo custo podem ser competitivas no mercado

Made available in DSpace on 2017-06-01T18:20:37Z (GMT). No. of bitstreams: 1 dissertacao_joao_caitano_alves_neto.pdf: 777326 bytes, checksum: 2e15b6afc4e315a3f94d61e55ec5b9ce (MD5) Previous issue date: 2012-09-04 / The reuse of agro-industrial waste as sources of carbon and nitrogen has been investigated in biotechnology for the production of enzymes by microorganisms. Among the microbial enzymes imported into Brazil, the proteases are applied in technological processes in the fields of detergents, pharmaceuticals, cosmetics, food, among others. The aim of this work was to produce proteases by submerged cultivation in the presence of agro-industrial waste. The determination of proteolytic activity was in the presence of 0.2 % azocasein. Submerged cultivation of Bacillus sp. strains isolated were carried out in Erlermeyer flasks. The maximum protease activity was determined in the presence of corn steep liquor. The concentration of the liquid metabolic by ultrafiltration of the metabolic liquid with proteolytic activity retained 80% of the activity. A factorial experimental design was carried out to investigate the stability of the metabolic liquid. The maximum proteolitic activity of the liquid metabolic cell-free (196 U/mL) was determined in the presence of 0.5 % sodium sorbate, 0.5 % calcium chloride, and 7.5 % of glycerol and polyethyleneglycol-200. The enzyme extract formulated retained 68 % of the proteolytic activity after 10 days at storage at room temperature (28 ˚C). The retentate with proteolytic activity showed optimum pH 9 and 11 and retention 90 - 100 % of the activity for 90 min at optimum pH; the optimum temperature was 50 ˚C e the maximum thermal stability was at 40 ˚C for 30 min at pH 11. The formulation of metabolic liquid concentrate with proteolytic activity which has thermal stability at alkaline pH is a bioproduct which can be used as an additive in detergents. / O reaproveitamento de resíduos agroindustriais como fontes de carbono e de nitrogênio tem sido investigado na área de biotecnologia para produção de enzimas por micro-organismos. Dentre as enzimas microbianas importadas no Brasil, as proteases são aplicadas no processamento tecnológico de detergentes, fármacos, cosméticos, alimentos, dentre outros. O objetivo deste trabalho foi produzir proteases por cultivo submerso utilizando resíduos agroindustriais. A determinação da atividade proteolítica ocorreu na presença de azocaseína a 0,2 %. Cultivos submersos de culturas isoladas de Bacillus sp. foram realizados em frascos de Erlermeyer. A atividade máxima de proteases foi determinada na presença de milhocina. A concentração do líquido metabólico com atividade proteolítica por ultrafiltração reteve cerca de 80 % da atividade inicial. Um planejamento experimental fatorial foi realizado para investigar a estabilidade do líquido metabólico. A maior atividade proteolítica média do líquido metabólico livre de células (196 U/mL) foi determinada na presença de sorbato de sódio a 0,5 %, cloreto de cálcio a 0,5 %, glicerol a 7,5 % e polietilenoglicol-200 a 0,5 %. O extrato enzimático formulado reteve 68 % da atividade proteolítica com 10 dias de armazenamento à temperatura ambiente (28 ˚C). O retentado com atividade proteolítica apresentou pH ótimo 9 e 11 e retenção de 90 - 100 % da atividade durante 90 min em pH ótimo; a temperatura ótima foi 50 ˚C e a estabilidade térmica máxima a 40 ˚C durante 30 min a pH 11. A formulação de líquido metabólico concentrado com atividade proteolítica que apresenta estabilidade térmica em pH alcalino é um bioproduto que pode ser utilizado como aditivo em detergentes.

This research investigated the effect of copper and nickel on the performance of a laboratory scale activated sludge system. The wastewater used for this research was the influent to the activated sludge process at the Hoechst Celanese cellulose acetate manufacturing plant, located at Narrows, Virginia. The influent wastewater to the experimental unit was pretreated with lime and then selected amounts of copper and nickel were added separately or together to evaluate their effects on the performance of the system. The Specific Uptake of Metal (SUM), Dissolved Metal (DM), Total Metal Loading Rate (TMLR), and Specific Total Metal Loading Rate (STMLR) were useful parameters for analysis of the effects of the metals on activated sludge performance. No significant changes in effluent COD, SS, and OUR were observed for the acclimated activated sludge when the selected amounts of metals were added but not when either was added separately. The settling characteristics of the activated sludge deteriorated when a combination of copper and nickel were added. The SUM increased at a faster rate at higher metal loading rates than at lower metal loading rates to the reactor. The increases in dissolved metal concentrations in the mixed liquor were a linear function of the metal loading rates. / Master of Science

The U.S. Department of Energy (DOE) emphasizes the importance of identifying secondary sources for energy-relevant critical elements, driven by the escalating demands of the high-tech industry and products. Elements such as Ni, Cu, and REEs, are crucial for the development of clean energy technologies such as solar panels, wind turbines, electric vehicles, and battery storage systems. As the global demands for these technologies grow in response to climate change and the push for sustainable energy solutions, securing a stable supply of critical elements becomes imperative. Secondary sources, including alkaline industrial waste, natural Magnesium-bearing minerals, and e-waste, offer a sustainable path forward. They not only help mitigate supply risks but also offer a potential source of Ca and Mg for carbon mineralization. The DOE's focus on secondary resources highlights the need to ensure the resilience of energy infrastructure and the transition towards a more sustainable and secure energy future. Thus, this study embarks on a critical exploration of sustainable mining practices from secondary resources and investigates the novel method for energy-relevant critical elements recovery, and the application of carbon mineralization techniques for CO₂ sequestration. The research traverses a proposed stepwise coprecipitation process integrated with a carbon mineralization process in alkaline industrial waste (e.g., iron slag) and natural Magnesium-bearing minerals (e.g., Olivine). This research also delves into the use of a mild in-situ mechanical grinding method for Au, Ni, and Cu recovery from printed circuit boards (PCBs). Further expanding on the theme of waste valorization, this study delves into the use of blast furnace slag (BFS) for ex-situ carbon mineralization, showcasing a stepwise pH swing-assisted hydrometallurgy process. This approach not only allows the recovery of REEs but also the storage of CO₂ by carbonation the Ca and Mg reach solution, illustrating the potential for industrial waste to mitigate climate change impacts and metal scarcity. The coprecipitation process for the selective recovery of Ce from Fe solutions is explored. Through detailed characterizations by ICP, XRD, XPS, and SEM, this research reveals the underlying mechanisms of Ce recovery and proposes a weak acid dissolution process for its efficient extraction, emphasizing the role of chemical engineering in enhancing resource recovery. In exploring the sustainable recovery of Ni and Mg from olivine minerals, the research highlights the connection between leaching kinetics, crystal phase and silicate structure by using XPS and XRD. The study showcases the feasibility of pH control and stepwise coprecipitation process techniques in optimizing the purity and crystallinity of magnesium carbonates, contributing to the broader goal of reducing environmental footprints and enhancing techno-economic feasibility. This study also presents a mild mechanical grinding assisted method for the recovery of precious metals from printed circuit boards (PCBs). This investigation analyses the mechanical properties such as Young’s modulus, hardness, and surface roughness by using analytical techniques such as nanoindentation and AFM. This novel approach to precious metal recovery not only demonstrates a significant improvement in the efficiency of metal recovery but also contributes to the growing body of knowledge on sustainable e-waste recycling practices.

M.Sc. (Zoology) / Please refer to full text to view abstract

The management of clinical waste is of great importance due to its infectious and hazardous nature that can cause risks on environment and public health. The study was conducted to evaluate clinical waste management practices and to determine the amount of waste generated in five purposively selected healthcare facilities in Gaborone City Council. The surveyed healthcare facilities were of different size, specialization and category and included a referral hospital, two clinics and two health posts. To examine clinical waste management practices the study employed a range of methods including questionnaire survey which targeted 105 stratified randomly selected healthcare workers and ancillary staff, formal interviews with facility managers, field observations and literature reviews. Compliance with the Botswana Clinical Waste Management Code of Practice, 1996 and Waste Management Act, 1998 and other related documents were used as standards to assess clinical waste management practices. The waste management practices were analysed for a week in each healthcare facility to capture the daily management practices. The generated clinical waste was weighed to compute the generation rates and was followed through the various management practices to the final disposal. Findings of the study revealed that clinical waste generation rates were: 0.75kg/patient/day for Princess Marina Hospital and 0.1 - 0.3kg/patient/day for clinics and health posts. Numerous aspects of clinical waste management were found to comply with the expected rules and standards at Princess Marina Hospital, but the clinics and health posts had less appropriate practices. Clinical waste generated at Princess Marina Hospital is quantified in reliable records and dedicated Infectious Control Officers are responsible for monitoring the management of clinical waste. The study revealed that clinics and health posts do not quantify clinical waste and there are no officers responsible for monitoring clinical waste and there are no documents for monitoring the management of clinical waste. The main treatment method of clinical waste for the surveyed healthcare facilities is incineration and it is being done properly. The study established that at least 80% of healthcare workers and ancillary staff have been vaccinated against hepatitis B and have received training in clinical waste management. Recommendations are given with the aim of improving clinical waste management practices in Gaborone City Council healthcare facilities. / Environmental Management / M. Sc. (Environmental Management)

Bibliography: leaves 123-130. The literature search and the findings from the investigation have been used to provide recommendations for a sector specific cooperative approach using regulation, self-regulation, voluntary agreements, economic incentatives and educational/information strategies to promote and acheive cleaner production in the South Australian foundry industry.

Thesis (M.Sc.)--University of Hong Kong, 1998. / Includes bibliographical references (leaf 61-62) Also available in print.