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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
431

Biodegradation of cyanide and subsequent nitrification-aerobic denitrification in cyanide containing watewater

Mekuto, Lukhanyo January 2014 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Chemical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology 2014 / Environmental legislation focusing on wastewater disposal in industries that utilise cyanide and/or cyanide-related compounds has become increasingly stringent worldwide, with many companies that utilise cyanide products required to abide by the Cyanide International Code associated with the approval of process certifications and management of industries which utilise cyanide. This code enforces the treatment or recycling of cyanide-contaminated wastewater. Industries such as those involved in mineral processing, photo finishing, metal plating, coal processing, synthetic fibre production, and extraction of precious metals, that is, gold and silver, contribute significantly to cyanide contamination in the environment through wastewater. As fresh water reserves throughout the world are low, cyanide contamination in water reserves threatens not only the economy, but also endangers the lives of living organisms that feed from these sources, including humans. In the mining industry, dilute cyanide solutions are utilised for the recovery of base (e.g. Cu, Zn, Ni, etc.) and precious metals (e.g. Au, Ag, etc.). However, for technical reasons, the water utilised for these processes cannot be recycled upstream of the mineral bioleaching circuit as the microorganisms employed in mineral bioleaching are sensitive to cyanide and its complexes, and thus the presence of such compounds would inhibit microbial activity, resulting in poor mineral oxidation. The inability to recycle the water has negative implications for water conservation and re-use, especially in arid regions. A number of treatment methods have been developed to remediate cyanide containing wastewaters. However, these chemical and physical methods are capital intensive and produce excess sludge which requires additional treatment. Furthermore, the by-products that are produced through these methods are hazardous. Therefore, there is a need for the development of alternative methods that are robust and economically viable for the bioremediation of cyanide-contaminated wastewater. Biological treatment of free cyanide in industrial wastewaters has been proved a viable and robust method for treatment of wastewaters containing cyanide. Several bacterial species, including Bacillus sp., can degrade cyanide to less toxic products, as these microorganisms are able to use the cyanide as a nitrogen source, producing ammonia and carbon dioxide. These bacterial species secrete enzymes that catalyse the degradation of cyanide into several end-products. The end-products of biodegradation can then be utilised by the microorganisms as nutrient sources. This study focused on the isolation and identification of bacterial species in wastewater containing elevated concentrations of cyanide, and the assessment of the cyanide biodegradation ability of the isolates. Thirteen bacterial isolates were isolated from electroplating wastewater by suppressing the growth of fungal organisms and these species were identified as species belonging to the Bacillus genus using the 16S rDNA gene. A mixed culture of the isolates was cultured in nutrient broth for 48 hours at 37°C, to which FCN as KCN was added to evaluate the species‟ ability to tolerate and biodegrade cyanide in batch bioreactors. Subsequently, cultures were supplemented solely with agro-waste extracts, that is, Ananas comosus extract (1% v/v), Beta vulgaris extract (1% v/v), Ipomea batatas extract (1% v/v), spent brewer‟s yeast (1% v/v) and whey (0.5% w/v), as the primary carbon sources. Owing to the formation of high ammonium concentration from the cyanide biodegradation process, the nitrification and aerobic denitrification ability of the isolates, classified as cyanide-degrading bacteria (CDB) was evaluated in a batch and pneumatic bioreactor in comparison with ammonia-oxidising bacteria (AOB). Furthermore, the effects of F-CN on the nitrification and aerobic denitrification was evaluated assess the impact of F-CN presence on nitrification. Additionally, optimisation of culture conditions with reference to temperature, pH and substrate concentration was evaluated using response surface methodology. Using the optimised data, a continuous biodegradation process was carried out in a dual-stage packed- bed reactor combined with a pneumatic bioreactor for the biodegradation of F-CN and subsequent nitrification and aerobic denitrification of the formed ammonium and nitrates. The isolated bacterial species were found to be gram positive and were able to produce endospores that were centrally located; using the 16S rDNA gene, the species were found to belong to the Bacillus genus. The species were able to degrade high cyanide concentration in nutrient broth with degradation efficiencies of 87.6%, 65.4%, 57.0% and 43.6% from 100 mg F-CN/L, 200 mg F-CN/L, 300 mg F-CN/L, 400 mg F-CN/L and 500 mg F-CN/L respectively over a period of 8 days. Additionally, the isolates were able to degrade cyanide in an agro-waste supported medium, especially in a medium that was supplemented with whey which achieved a degradation efficiency of 90% and 60% from 200 mg F-CN/L and 400 mg F-CN/L, respectively over a period of 5 days. The nitrification ability of the isolates was evaluated and the removal of NH4 +/NO3 - by the CDB and AOB in both shake flasks and pneumatic bioreactor was determined to be pH dependent. The maximum NH4 +/NO3 - removal evaluated over a period of 8 days for CDB and 15 days for AOB, observed at pH 7.7 in shake flasks, was 75% and 88%, respectively, in the absence of F-CN. Similarly, the removal of NH4 +/NO3 - in a pneumatic bioreactor was found to be 97.31% for CDB and 92% for AOB, thus demonstrating the importance of aeration in the designed process. The nitrification by CDB was not inhibited by cyanide loading up to a concentration of 8 mg FCN/ L, while the AOB were inhibited at cyanide loading concentration of 1 mg F-CN/L. The CDB removed the NH4 +/NO3 - in PBSs operated in a fed-batch mode, obtaining efficiencies >99% (NH4 +) and 76 to 98% (NO3 -) in repeated cycles (n = 3) under F-CN (≤8 mg F-CN/L). The input variables, that is, pH, temperature and whey-waste concentration, were optimised using a numerical optimisation technique where the optimum conditions were found to be: pH 9.88, temperature 33.60 °C and whey-waste concentration 14.27 g/L, under which 206.53 mg CN-/L in 96 h can be biodegraded by the microbial species from an initial cyanide concentration of 500 mg F-CN/L. Furthermore, using the optimised data, cyanide biodegradation in a continuous mode was evaluated in a dual-stage packed-bed bioreactor connected in series to a pneumatic bioreactor system used for simultaneous nitrification including aerobic denitrification. The whey-supported Bacillus sp. culture was not inhibited by the free cyanide concentration of up to 500 mg F-CN/L, with an overall degradation efficiency of ≥99% with subsequent nitrification and aerobic denitrification of the formed ammoniu and nitrates over a period of 80 days.
432

Codigestão anaeróbia de resíduos bovinos e suínos: caracterização química e produção de biofertilizante para uso em cultura de milho

Costa, Antonio Marcos Tubiana de 10 October 2014 (has links)
Ao abordar o tema contaminação ambiental, logo se recorda a quantidade de resíduos domésticos e urbanos, que são gerados nas cidades e metrópoles, os quais muitas vezes não recebem nenhum tipo de tratamento. Porém, problemas de contaminação ambiental também estão vinculados à agricultura, onde são gerados resíduos orgânicos com elevados potenciais poluidores. Dessa forma, o projeto objetivou estudar o processo de codigestão anaeróbia de dejetos bovinos e suínos oriundos de sistemas de produção de suínos e atividade pecuária leiteira, como alternativa para tratamento destes tipos de matrizes, além de investigar a eficiência do biofertilizante produzido a partir das matrizes de resíduos em cultura de milho. Para isso, se coletaram amostras de dejetos de bovinos e suínos para caracterização e posterior utilização nos ensaios com tratamentos diferentes. Na sequência se fez a preparação das amostras para os ensaios utilizando-se de inoculos diferenciados (in natura, inoculo da rede de saneamento básico e inoculo isolado de dejeto bovino) com o propósito de avaliar a degradação dos dejetos via codigestão anaeróbia. Em cada ensaio citado se fizeram vinte tratamentos, via planejamento fatorial 2³, com seis pontos centrais, sendo as variáveis de entrada: tempo, fração de sólidos e razão de mistura; e as variáveis respostas (dependentes): pH, razão AV/AL, umidade, série de sólidos, razão SV/ST, redução de sólidos totais, DQO, redução de DQO, nitrogênio total, fósforo e potássio. Fez-se depois o estudo cinético do processo, se utilizando do ensaio in natura com proporção de mistura de 75% em dejeto suíno e 25% em dejeto bovino, com fração de sólidos de 8,9%, mediante Teste de Tukey. Após a estabilização da biomassa utilizada, fez-se a aplicação do biofertilizante em cultura de milho, comparando-se com fertilizante comercial (ureia), verificando-se o crescimento e desenvolvimento desta cultura. No planejamento fatorial se concluiu mediante análise de Tukey e considerando a importância de cada variável resposta que o ensaio in natura apresentou as melhores condições operacionais, pois se teve o maior número de variáveis respostas sendo consideradas satisfatórias, como razão AV/AL, razão SV/ST e redução da DQO. Observou-se durante o estudo cinético que a biomassa apresentou estabilização próxima aos vinte dias de tratamento, indicando a degradação orgânica dos dejetos em codigestão e produção de biofertilizante, o qual é mais estável e menos poluente ao ambiente, sendo utilizado como opção no processo de fertilização de culturas agrícolas como o milho. No que diz respeito à utilização do biofertilizante (40 kg.ha-1), notou-se semelhança deste se comparado à ureia (40 kg.ha-1) para o cultivo de milho, podendo ser uma alternativa interessante de destinação dos dejetos, diminuindo a poluição ambiental causada pelo manejo inadequado. / When discussing environmental contamination, just remember the amount of domestic and urban waste that are generated in towns and cities, which often do not receive any treatment. However, problems of environmental contamination are linked to agriculture, where organic waste with high potential polluters is generated. This way, the project had the objective of studying the anaerobic codigestion process of cattle and pig waste from the swine production systems and dairy farming activity, as an alternative to the treatment of these kinds of matrices, as well as to investigate the efficiency of biofertilizer matrices produced from the waste in cultured maize. For this, samples of manure from cattle and pigs were collected for characterization and subsequent use in the tests with different treatments. Then, the preparation of samples for the tests using the different inocula were made (in natura, inoculum of sanitation and inoculum isolated from bovine manure), in order to evaluate the degradation of waste via anaerobic codigestão. In each test mentioned twenty treatments were made, via 2³ factorial design with six central points, where the input variables: time, fraction of solids and mixing ratio; and the response variables (dependent): pH, ratio AV/AL, moisture, solids, ratio SV/ST, reduction of total solids, COD, reduction of COD, total nitrogen, phosphorus and potassium. It was made after the kinetic study of the process, using the test in natura mix ratio of 75% in swine manure and 25% in cattle manure with solid fraction of 8.9% by the Tukey test. After stabilization of the biomass used, there was the application of biofertilizers in crop maize compared with commercial fertilizer (urea), verifying the growth and development of this culture. In factorial design was completed by Tukey analysis and considering the importance of each variable response that the test in natura presented the best operating conditions, because it had the largest number of variable responses being considered satisfactory ratio as AV / AL, ratio SV / ST and COD reduction. It was observed during the kinetic study that biomass showed stabilization next to twenty days of treatment, indicating the degradation of organic waste in codigestão and biofertilizer production, which is more stable and less polluting to the environment, being used as an option in process fertilization of agricultural crops such as maize. Regarding the use of biofertilizers (40 kg.ha-1), this similarity was noted compared to urea (40 kg.ha-1) for the cultivation of maize and it may be an interesting alternative for allocation of waste, reducing environmental pollution caused by improper handling.
433

Codigestão anaeróbia de resíduos bovinos e suínos: caracterização química e produção de biofertilizante para uso em cultura de milho

Costa, Antonio Marcos Tubiana de 10 October 2014 (has links)
Ao abordar o tema contaminação ambiental, logo se recorda a quantidade de resíduos domésticos e urbanos, que são gerados nas cidades e metrópoles, os quais muitas vezes não recebem nenhum tipo de tratamento. Porém, problemas de contaminação ambiental também estão vinculados à agricultura, onde são gerados resíduos orgânicos com elevados potenciais poluidores. Dessa forma, o projeto objetivou estudar o processo de codigestão anaeróbia de dejetos bovinos e suínos oriundos de sistemas de produção de suínos e atividade pecuária leiteira, como alternativa para tratamento destes tipos de matrizes, além de investigar a eficiência do biofertilizante produzido a partir das matrizes de resíduos em cultura de milho. Para isso, se coletaram amostras de dejetos de bovinos e suínos para caracterização e posterior utilização nos ensaios com tratamentos diferentes. Na sequência se fez a preparação das amostras para os ensaios utilizando-se de inoculos diferenciados (in natura, inoculo da rede de saneamento básico e inoculo isolado de dejeto bovino) com o propósito de avaliar a degradação dos dejetos via codigestão anaeróbia. Em cada ensaio citado se fizeram vinte tratamentos, via planejamento fatorial 2³, com seis pontos centrais, sendo as variáveis de entrada: tempo, fração de sólidos e razão de mistura; e as variáveis respostas (dependentes): pH, razão AV/AL, umidade, série de sólidos, razão SV/ST, redução de sólidos totais, DQO, redução de DQO, nitrogênio total, fósforo e potássio. Fez-se depois o estudo cinético do processo, se utilizando do ensaio in natura com proporção de mistura de 75% em dejeto suíno e 25% em dejeto bovino, com fração de sólidos de 8,9%, mediante Teste de Tukey. Após a estabilização da biomassa utilizada, fez-se a aplicação do biofertilizante em cultura de milho, comparando-se com fertilizante comercial (ureia), verificando-se o crescimento e desenvolvimento desta cultura. No planejamento fatorial se concluiu mediante análise de Tukey e considerando a importância de cada variável resposta que o ensaio in natura apresentou as melhores condições operacionais, pois se teve o maior número de variáveis respostas sendo consideradas satisfatórias, como razão AV/AL, razão SV/ST e redução da DQO. Observou-se durante o estudo cinético que a biomassa apresentou estabilização próxima aos vinte dias de tratamento, indicando a degradação orgânica dos dejetos em codigestão e produção de biofertilizante, o qual é mais estável e menos poluente ao ambiente, sendo utilizado como opção no processo de fertilização de culturas agrícolas como o milho. No que diz respeito à utilização do biofertilizante (40 kg.ha-1), notou-se semelhança deste se comparado à ureia (40 kg.ha-1) para o cultivo de milho, podendo ser uma alternativa interessante de destinação dos dejetos, diminuindo a poluição ambiental causada pelo manejo inadequado. / When discussing environmental contamination, just remember the amount of domestic and urban waste that are generated in towns and cities, which often do not receive any treatment. However, problems of environmental contamination are linked to agriculture, where organic waste with high potential polluters is generated. This way, the project had the objective of studying the anaerobic codigestion process of cattle and pig waste from the swine production systems and dairy farming activity, as an alternative to the treatment of these kinds of matrices, as well as to investigate the efficiency of biofertilizer matrices produced from the waste in cultured maize. For this, samples of manure from cattle and pigs were collected for characterization and subsequent use in the tests with different treatments. Then, the preparation of samples for the tests using the different inocula were made (in natura, inoculum of sanitation and inoculum isolated from bovine manure), in order to evaluate the degradation of waste via anaerobic codigestão. In each test mentioned twenty treatments were made, via 2³ factorial design with six central points, where the input variables: time, fraction of solids and mixing ratio; and the response variables (dependent): pH, ratio AV/AL, moisture, solids, ratio SV/ST, reduction of total solids, COD, reduction of COD, total nitrogen, phosphorus and potassium. It was made after the kinetic study of the process, using the test in natura mix ratio of 75% in swine manure and 25% in cattle manure with solid fraction of 8.9% by the Tukey test. After stabilization of the biomass used, there was the application of biofertilizers in crop maize compared with commercial fertilizer (urea), verifying the growth and development of this culture. In factorial design was completed by Tukey analysis and considering the importance of each variable response that the test in natura presented the best operating conditions, because it had the largest number of variable responses being considered satisfactory ratio as AV / AL, ratio SV / ST and COD reduction. It was observed during the kinetic study that biomass showed stabilization next to twenty days of treatment, indicating the degradation of organic waste in codigestão and biofertilizer production, which is more stable and less polluting to the environment, being used as an option in process fertilization of agricultural crops such as maize. Regarding the use of biofertilizers (40 kg.ha-1), this similarity was noted compared to urea (40 kg.ha-1) for the cultivation of maize and it may be an interesting alternative for allocation of waste, reducing environmental pollution caused by improper handling.
434

Hospodaření s odpady v Jihočeském kraji / Waste Managament Of South Bohemia

MAŤHA, Martin January 2010 (has links)
This Diploma thesis is focuses on a problem of waste manegament of South Bohemia. It analyses present problems and situation. The aim of this work is to introduce basic principles of handling the waste and waste managament to the readers. It also provide information on financial possibilities, interventions of the public and private sectors and legislative criteria connected with the duties of the waste management.
435

Avaliação da contaminação provocada por para-raios radioativos de amerício-241 descartados em lixões

MARUMO, JULIO T. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:52:19Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:31Z (GMT). No. of bitstreams: 0 / Os pára-raios radioativos foram fabricados no Brasil até 1989, quando a Comissão Nacional de Energia Nuclear (CNEN) suspendeu a concessão de uso de material radioativo nesses artefatos. Desde então, o pára-raios radioativo tem sido substituído por outro, do tipo Franklin, e recolhido como rejeito radioativo. Entretanto, apenas 23 % do total fabricado no país foram entregues à CNEN. Esta situação é preocupante, pois a chance, desses artefatos serem descartados como resíduo comum e chegarem a lixões, é grande, uma vez que, segundo dados do Instituto Brasileiro de Geografia e Estatística (IBGE), em 2000, 63,6 % dos municípios brasileiros dispunham o resíduo nesses locais. Além disso, o amerício, o radionuclídeo mais empregado, é classificado como sendo um elemento de alta toxicidade, quando ingerido ou inalado. No presente trabalho, foram realizados experimentos de migração de Am-241 em lisímetros, com o objetivo de se avaliar o risco de contaminação provocada por pára-raios radioativos descartados como resíduo comum. Fontes radioativas removidas de pára-raios foram inseridas em lisímetros preenchidos com resíduo orgânico, coletado no restaurante do Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, e chorume gerado foi periodicamente analisado para determinar suas características como pH, potencial redox, teor de sólidos e a concentração do material radioativo. O crescimento microbiano também foi avaliado, pelo método de contagem direta do número de unidades formadoras de colônia. A estimativa de risco foi baseada no cálculo de dose para membros do público, sendo a ingestão de água a via mais provável de exposição. O valor obtido foi cerca de 1000 vezes inferior ao limite de dose anual estabelecido, pela Comissão Internacional de Proteção Radiológica (ICRP), demonstrando que o risco de contaminação provocado pelo descarte de pára-raios em lixões é baixo. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
436

Otimização e validação de metodologia analítica para determinação de metais e semimetais em efluentes líquidos por espectrometria de emissão óptica com plasma de argônio (ICP-OES) / Optimization and validation of analytical methodology for determination of metals and semimetals in wastewater by inductively coupled plasma optical emission spectrometry (ICP-OES)

MARQUES, JOYCE R. 08 April 2016 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-04-08T12:43:32Z No. of bitstreams: 0 / Made available in DSpace on 2016-04-08T12:43:32Z (GMT). No. of bitstreams: 0 / Além da Resolução CONAMA 430/11 definir limites para o lançamento de efluentes, também define que os laboratórios que realizam análises ambientais devem ser acreditados pelo INMETRO e também devem ter sistema de controle de qualidade implantado. Para o atendimento destes requisitos legais, o presente trabalho visa otimizar, validar e implantar a metodologia analítica desenvolvida e aplicada no Centro de Química e Meio Ambiente (CQMA) do Instituto de Pesquisas Energéticas e Nucleares (IPEN/ CNEN SP) para a quantificação dos elementos cádmio, chumbo, cobre, prata, crômio, zinco, estanho, níquel, ferro, bário, manganês e boro em amostras de efluentes líquidos por Espectrometria de Emissão Óptica com Plasma Acoplado Indutivamente (ICP-OES). Esta metodologia é utilizada para a determinação de metais e semimetais em amostras coletadas no Programa de Monitoramento Ambiental PMA-Q do IPEN. Todo o processo de validação desta dissertação foi baseado no guia Orientativo do INMETRO DOQ-CGCRE-008 - Orientação sobre Validação de Métodos Analíticos. No estudo de seletividade verificou-se que a matriz não interfere nas curvas analíticas do método em estudo; a faixa de trabalho foi determinada com base nos valores máximos permitidos (VMP) pelas legislações ambientais vigentes (Resolução CONAMA 430/11, DE 8.468/76 e DE 15.425/80) e no histórico de dados do PMA-Q e todas as curvas analíticas apresentam comportamento linear na faixa de trabalho abrangida pelo método; os limites de detecção e quantificação do método atendem aos limites definidos pelas legislações ambientais vigentes e à precisão e exatidão necessárias; a precisão e exatidão apresentaram resultados satisfatórios para a finalidade do método analítico; além do método demonstrar-se robusto, embora seja necessário que o analista se atente à variação de alguns fatores no momento da realização das análises. Também foi possível realizar a estimativa de incerteza do método de modo que fosse alcançado nível de confiança de 95% dos resultados, foram levadas em consideração todas as etapas de preparo e análise das amostras e foi possível obter incerteza global entre 4,6% e 12,23%. Através dos resultados obtidos nos testes estatísticos e pela avaliação do analista foi possível verificar que o método desenvolvido e aplicado no CQMA é adequado para o fim pretendido. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
437

Utilização de resíduos de catalisador (ECAT) e cinzas da casca de arroz (CCA) na elaboração de vidros silicatos soda-cal destinados a embalagem / Use of rice rusk ash and spent catalyst as a source of raw material for the production and characterization of soda-lime silicate glasses destined for packaging

ARAUJO, MARIANA S. de 22 June 2016 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-06-22T12:39:08Z No. of bitstreams: 0 / Made available in DSpace on 2016-06-22T12:39:08Z (GMT). No. of bitstreams: 0 / Estudo realizado acerca da utilização de dois resíduos sólidos industriais (RSI) gerados em grande quantidade no Brasil, na obtenção de vidros soda-cal destinados à produção de embalagens. Os resíduos avaliados foram a cinza de casca de arroz (CCA) e resíduo do catalisador usado das unidades de Craqueamento Catalítico Fluido das Petroquímicas (ECAT), ambos podem ser classificados como resíduos sólidos de classe II de acordo com a norma NBR 10.004. Esta nova proposta para destinação desses resíduos é uma alternativa às atuais disposições, buscando não apenas minimizar os impactos ambientais gerados, mas também a valorização dos mesmos como matérias-primas. Para a produção das amostras, além da utilização dos RSIs, foram também utilizados óxidos fundente (Na2CO3) e estabilizante (CaO). Os resultados obtidos demonstraram que ambos podem ser usados como recebidos (sem tratamento prévio) substituindo matérias-primas importantes, fontes de Al2O3 e SiO2, necessárias para a formação de vidros. As amostras obtidas apresentaram a cor âmbar devido a presença de níquel (íons Ni2+) proveniente do ECAT e transmitância óptica de 18%. Estas, ainda demonstraram boa homogeneidade, i.e., ausência de bolhas e estriais e, resistências hidrolíticas média de 1,33x10-8 g/cm²·dia (superior à um vidro comercial de composição semelhante) de acordo com a ISO695-1984. O vidro obtido é adequado para aplicações que exigem baixa transmitância como embalagens de vidros em geral, os quais não requerem perfeita visibilidade e transparência. O teor de incorporação na composição final das amostras foi de aproximadamente 78% em massa. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
438

Aspects of water quality, metal contamination of sediment and fish in the Olifants River, Mpumalanga.

Kotze, Petrus Jacobus 17 August 2012 (has links)
M.Sc. / Pollution of the earth is presently one of the most important environmental issues of the world and various attempts, including creation of public awareness have been initiated over the past few years to address this situation. There is especially a global concern about the progressive pollution of valuable freshwater systems which most organisms, including humans, are reliant upon. This includes South Africa's aquatic ecosystems, many of which have been degraded over the past few decades. The Olifants River in Mpumalanga is one of the most threatened river systems in South Africa. It is impacted by various anthropogenic activities, particularly mining in the upper catchment, and urbanisation, industrial and agricultural activities in the upper and lower catchments. Previous investigations have shown that these activities are responsible for the degradation of this river system. The broad objective of this study was to obtain data on water and sediment quality, as well as bioaccumulation of metals in fish via monitoring of the Olifants River. It formed part of a major study concerned with the experimental investigation of lethal and sub-lethal effects of metals on fish physiology, supported by a field investigation into the water quality and metal contamination of the biotic and abiotic components of the Olifants River system. Physico-chemical properties of the water as well as the concentrations of some metals (Al, Fe, Cu, Zn, Ni, Mn, Pb & Cr) in the water and sediment were seasonally investigated. The extent of bioaccumulation of these metals in selected organs/tissues (muscle, gills, liver & skin) of Oreochromis mossambicus and Clarias gariepinus from Loskop Dam (upper catchment) and Mamba Weir, Kruger National Park (lower catchment) was also investigated. High levels of various macro-constituents and metals were detected at many sites in the study area and in many cases they exceeded the guideline limits set for aquatic ecosystems. Localities 2, 3, 6, 8, 10, 12 and 17 were observed to be severely impacted (see Chapter 9- Table 9.1) by elevated concentrations of pollutants influencing variables such as TDS and sulphates. This confirms that these sites are being impacted by mining. This was further confirmed by low pH-values at localities 3, 5, 8, 9, 10 and 12 which indicate on acid mine drainage originating from the many coal mines in the upper catchment of the Olifants River. Nutrient enrichment (elevated levels of phosphates, nitrates and nitrites) occurred at many sites in the catchment but in particular at localities 3, 4, 6, 10, 11, 14, 15 and 17. Point source pollution from sewage treatment works and non-point sources from agricultural runoff and informal settlements are the main contributors to these elevated levels of nutrients. The Selati River, impacted in particular by elevated phosphate levels, is the main contributor to the high nutrient levels detected at locality 17. It is evident from the evaluation of the metal concentrations in the water and sediment (Table 9.2) that most of the sites in the Olifants River catchment are being impacted by metal pollution. Oreochromis mossamhicus and C gariepinus sampled at selected sites in the Olifants River accumulated selected metals in the following order; Fe>Zn>Al>Cr>Ni>Pb>Mn>Cu. Levels were generally high in the liver and gills, while much lower levels were detected in the skin and muscle tissues. Gill tissue is in direct contact with the aqueous environment and therefore gives a good indication of the extent of exposure. Skin tissues usually contained relatively low levels of metals (except for Zn). Although muscle tissues usually accumulated low metal concentrations it is an important tissue to monitor in bioaccumulation studies as it can lead to metal poisoning if contaminated muscle tissues are consumed by humans. Adult specimens were mostly sampled and within this range there was a slight decrease in Cu, Al, Fe, Ni, Mn and Cr concentrations with increasing age. Temporal variation in metal accumulation by fish possibly occurred due to variations in metal concentrations in the water and sediment at a locality. These differences were caused by seasonal variation in climatical conditions (eg. rainfall, temperature), as well as temporal fluctuations of pollutant inputs into the river system. Aquatic organisms at both localities 15 (Loskop Dam) in the upper catchment and 17 (Mamba weir, Kruger National Park) in the lower catchment are at present being chronically exposed to elevated levels of the investigated metals, compared to both the control site and results in literature. The impact of the highly polluted Selati River in the lower catchment was evident in the difference between metal concentrations detected in fish at locality 17, and at locality 19 (Phalaborwa Barrage) upstream of the Olifants-Selati confluence. The present study clearly indicates that the Olifants River is subjected to various sources of pollution which could be detrimental to the health of this aquatic ecosystem. It is recommended (see Chapter 9) that a multi-disciplinary approach including a biomonitoring programme, should be followed to ensure a sustainable freshwater ecosystem.
439

Evaluation of a health assessment index with reference to metal bioaccumulation in Clarias gariepinus and aspects of the biology of the parasite Lamproglena clariae.

Marx, Hazel Mary 14 August 2012 (has links)
M.Sc. / The catchment area of the Olifants River has, over a number of years, been exposed to extensive mining, agriculture and urbanisation activities in the Witbank-Middelburg and Phalaborwa regions which has largely contributed to the deterioration of water quality. Of major concern is the influence anthropogenic activities have on the aquatic ecosystem of the Olifants River within the Kruger National Park and how me health of fish residing In these waters is affected. To determine fish health, a biological monitoring method, the Health Assessment Index (H41), was tested for the first time In South Africa. Four surveys were conducted at Mamba and Balule In the Olifants River, Kruger National Park during 1994 (February, May, July and November). An additional survey was conducted in February 1995 at Loskop Dam. Samples of water and sediment were taken for analysis of metals and physical and chemical water parameters. A maximum of 20 Clarias gariepinus fish were sampled at each location. Evaluation of the fish was done according to guidelines set in the HAI and parasite population composition (prevalence, abundance, mean intensity) was determined. Organ and tissue samples including gills, liver, muscle and skin were analysed for the bioaccumulation of chromium, copper, Iron, manganese, nickel, lead, strontium and zinc, using atomic absorption spectrophotomeby. Metal concentrations in the water at Mamba and Balule were within guideline limits, whereas concentrations at Loskop Dam were above guidelines. As reflected by the application of the Aquatic toxicity Index, Loskop Dam presented with the poorest water quality followed by Mamba then Balule. It was found that certain physical and chemical variables namely fluoride, potassium, sulphate and total dissolved solids concentrations at Mamba and Balule were relatively high, particularly during drier months. Metals accumulated in organs and tissues, with the highest concentrations In the gills followed by the liver, skin and muscle. The discriminant analysis, utilising metal bloaccumulation, discriminates between water quality at Mamba and Balule, revealing a 100 % classification probability for each survey. Values obtained In the application of the HAI indicated that variables with good predictor accuracy were plasma protein, all parasites, endoparasites, liver, white blood cell counts, ectoparasites, skin, fins and gills. The discriminant function for the HAI generally Indicated variables similar to those exhibiting high predictor accuracy. The discriminant function showed relatively low classification probability for each survey. In case 1, where separate endo- and ectoparasite variables were Included in the determination of me discriminant function, probability for me entire study ranged between 47.5 % and 84.2 %. In case 2, where endo- and ectoparasite variables were given a refined score rating system, probability ranged between 62.5 % and 100 %. The low classification probability Indicates either the Importance of repetitive testing for this technique or a total departure from it. Results showed that fish populations with higher HAI values are found in water of poorer quality (Mamba), while healthier fish populations i.e. with lower RAI values are found In water of better quality (Balule). Parasite data shows a similar tendency by indicating that ectoparasites are abundant in water of higher quality, while endoparasftes increase in water of poorer quality. The HAI reflects the condition of fish populations in relation to their aquatic environment, therefore, the HA/ gives an indication of water quality and should be used as a first level screening tool. If complemented by a parasite survey, distinguishing between endoand ectoparasites, the results from the HAI will be enhanced.
440

Waste management in the pharmaceutical industry : an evaluation report of Dr Reddy's Laboratories

Letsitsi, Ezekiel Tebogo January 2013 (has links)
The pharmaceutical industry must worry about managing pharmaceutical waste as it poses a health risk to human beings and its presence in the environment can also contribute to loss of biodiversity. Ngwuluka, Ochekpe, and Odumosu (2011: 11259) state that “Pharmaceuticals, though used to treat and manage diseases, are poisons, which justify the growing concerns about their presence in the environment.” Various forms of pharmaceutical waste exist, Ngwuluka et al. (2011) identified the following forms of pharmaceutical waste: Expired dosage forms, non-reworkable formulations, spilled pharmaceuticals, rejected active pharmaceutical ingredients, expired active pharmaceutical ingredients, and wastewater resulting from the water used for process operations during manufacturing and could come from the water used to clean equipment, pipes and floors, and would contain amongst other materials, chemicals and active pharmaceutical ingredients (APIs). A review on the pharmaceutical industry and the progress they have made in environmental management by generating health, safety and environmental programs, preventing pollution, waste minimization, recycling and reusing materials, investing in projects and facilities to ensure environmental sustainability have been established (Berry & Rondinelli, 2000). Dr. Reddy’s Laboratories is an Indian based pharmaceutical company which imports, markets and sells medicines in South Africa. Dr. Reddy’s has plans to set up a manufacturing plant in South Africa. The purpose of this study is to research waste management practices at Dr. Reddy’s plant in India and to draw parallels between India’s and South Africa’s waste legislation. This is to enable Dr. Reddy’s to review all aspects of its waste management systems, in order to revise where necessary and to improve the overall achievement of its waste management objectives in order to become a more sustainable organisation and to meet South African Waste legislation before setting up a plant in South Africa. 3 ii. Objective of the Evaluation Report The purpose of this research is to evaluate and analyse the development and implementation of a waste management system in a pharmaceutical company, specifically Dr. Reddy’s Laboratories. This is primarily to enable the company to review and analyse all aspects of waste management pertaining to pharmaceutical manufacturing and to revise or improve where necessary to ensure adherence to waste regulations as outlined by government. The following research goals have been also been identified:  To identify and describe waste management practices at Dr. Reddy’s Laboratories, on the inherent assumption by the researcher that the company has a successful waste management strategy that would need to be reviewed to identify areas of improvement before expanding manufacturing facilities into South Africa.  To evaluate, assess and compare similarities and/or differences between the identified South African Legislation for Waste Management with those identified during research conducted at Dr. Reddy’s iii. Importance of the Research Conducted Waste Management is important in that it not only removes from the environment, substances that can be harmful to humans and animals but it also enables an organisation to be more sustainable. According to Seadon (2010: i) “Integrated waste management is considered from a systems’ approach, with a particular emphasis on advancing sustainability”. The study will provide guidance to senior management, shop floor managers and employees who work in Dr. Reddy’s manufacturing plants as well as overall employees at Dr. Reddy’s on how to successfully implement a Waste Management programme to enhance sustainability at the organisation and realise the benefits to the organisation of being more sustainable. Weybrecht (2010) identified the following benefits that companies could gain by adopting sustainable waste management practices: reduced costs, resource preservation, keeping up with legislation, enhanced reputation, business differentiation from competitors, and attraction and retention of quality employees, and customer need satisfaction amongst many other benefits. This research needs to address the gap in analysing waste management practices (with more emphasis on waste treatment, waste minimisation, re-use, recycling and disposal), and implementation and understanding of waste management in the pharmaceutical industry as prior research was done mostly in other chemical industries and not to a large scale in the pharmaceutical industry. South African Waste Legislation, Indian Waste Legislation (as Dr. Reddy’s is based in India), as well as International Pharmaceutical Waste Management Guidelines, and International Pharmaceutical Good Manufacturing Practices provide a framework and benchmark of leading pharmaceutical waste management practices that can guide Dr. Reddy’s Laboratories’ leadership into integrating their waste management practices into their plans of setting up a manufacturing plant in South Africa. 5. Research Methodology This is evaluation research in the form of a case study and the data collection method employed is the conduction of a survey through questionnaires. The evaluation research also involves a document analysis of the organisation’s 2011 and 2012 annual reports, Dr. Reddy’s 2010 Sustainability Report as well as literature compiled by the organisation’s Corporate Communications Division. The research would also include review of existing literature on waste management. v. Structure of Dissertation This dissertation consists of three sections. Section 1: The Evaluation Report The section introduces the research area, provides the objectives of the research, provides contextual background information and describes the rationale for conducting the research. This section further describes Dr. Reddy’s waste management practice as outlined in relevant company documentation; it is also intended to highlight the specific waste management processes that were followed in the formulation and implementation of the waste management strategy. This section further describes the sample and presents the results of the survey, where the results are collated and reviewed in the context of the criteria set in the South African Waste Legislation, Indian Waste Legislation, as well as in International Pharmaceutical Waste Management Guidelines, and International Pharmaceutical Good Manufacturing Practices. The overall findings of this case study suggest that although management at Dr. Reddy’s are satisfied with waste management practices and results achieved at it manufacturing plant, there is however dissatisfaction amongst employees who believe the organisation has not successfully disseminated information and sufficiently trained them on waste management policies, processes and practices. There is therefore a desire amongst employees to be trained and to see the company improve on its waste management processes, this desire is a very important attribute as it indicates that employees at Dr. Reddy understand and are committed to the importance of waste management. Future research should be conducted to measure the legal impact of non-compliance to legislation governing waste management in the pharmaceutical company. Section 2: Literature Review The objective of the literature review is to provide a critical assessment and evaluation of previous research in the field of waste management in general as prior research was done mostly in other industries and not to a large scale in the pharmaceutical industry. The literature review evaluates the key elements of an effective waste management strategy implementation and is followed by a review of literature pertaining to the description of Pharmaceutical waste. Section 3: Research Methodology This section presents a description of how the work in this research was conducted. It presents the research process followed in compiling this case study, represented by the aims and objectives, research methodology and design, data collection techniques and data analysis.

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