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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.
1

Metal recycle and recovery

Hussain, Zaib-un-nisa January 1999 (has links)
The development of techniques for the removal and recovery of metals from industrial effluent taking account of the consequences of the definition of waste in the Basel Convention on transfrontier shipment of waste is reported. The use of fluidised bed cell electrolysis in the recovery of metals from dilute solutions is investigated, and the conditions for recovery optimised. For the first time the application of a novel activated carbon cloth concentrator cell to recover metals from effluent solutions is reported and the conditions for its use optimised. Comparative studies using conventional mesh and plate electrodes, and novel activated carbon cloth electrode for the recovery of cobalt from dilute solution, and copper from three different hydrometallurgical solutions viz (i) Cu/Zn, (ii)Cu/Zn/Fe and (iii) Cu/Zn/Cd containing effluents were carried out. Application of concentrator cell technology including activated carbon cloth and ion exchange resin to the recovery of metals, including precious group metals, from industrial as-supplied samples is reported. Optimisation leads to successful recovery of iridium and palladium from very dilute solutions. The alternative recovery of metal as added-value chemicals is also investigated. The Basel Convention is concerned with transfrontier shipment of waste from developed to developing countries and has produced a need to investigate the leachability of metals in various forms. In this work the leachability of copper and zinc is studied under various conditions that model environmental situations and the results have been used to develop a methodology to determine whether a metal containing material would be subject to a shipment ban under the Convention. As part of the development of the methodology, leaching studies were also carried out on single chemical compounds of copper, zinc, cadmium and lead, and their bioavailability determined.
2

Electrochemical preparation and application of the ferrate (VI) ion for wastewater treatment

Denvir, Adrian James January 1995 (has links)
No description available.
3

Microbial degradation of aromatic compounds in a Gravel Bed Hydroponic (GBH) system

Addleton, Andrew Mark January 1997 (has links)
No description available.
4

Qualidade do solo em locais de disposição de vinhaça - Assentamento Sepé Tiaraju - Serrana SP / Soil quality in places of Vinasse - Settlement of Landless Agricultural Laborers Sepé Tiarajú, Serrana - SP

Arcaro, Nathália Pozzi, 1983- 22 August 2018 (has links)
Orientador: Sueli Yoshinaga Pereira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-22T00:31:48Z (GMT). No. of bitstreams: 1 Arcaro_NathaliaPozzi_M.pdf: 2439576 bytes, checksum: 7988db46a010845295ed8c71b1cbb79c (MD5) Previous issue date: 2013 / Resumo: A vinhaça constitui um efluente proveniente da indústria sucro-alcooleira, utilizado principalmente na fertirrigação de lavouras de cana-de-açúcar, por. Contudo, diversos trabalhos indicam que a aplicação e disposição de vinhaça em solo ocasionam a contaminação destes meios por sais e metais, além de proporcionar a alteração de características físico-químicas e biológicas do solo. O objetivo do presente estudo visou avaliar a qualidade do solo em um tanque/lagoa de disposição de vinhaça, sem impermeabilização, e que foi utilizada por 20 anos e há 8 anos se encontra inativo. Foram realizadas 2 sondagens dispostas no interior do tanque de vinhaça e em uma área de background com profundidades de 24 e 32 metros. As amostras de solo foram coletadas em intervalos de 1 metro até o nível d'água. As análises de solo foram realizadas por fluorescência de raios x para determinação das frações em massa de óxidos e elementos traços, além de ensaios de perda ao fogo e análise microbiológica de solo para fungos e leveduras. Também foram realizados ensaios de lixiviação com água deionizada e ácida nítrico, analisada por cromatografia e ICP-MS. Os resultados das amostras de solo e dos ensaios de lixiviação indicam que as amostras de solo coletadas no interior do tanque de vinhaça apresentaram indícios de salinização em comparação com as amostras de solo de controle. Os resultados das análises microbiológicas indicaram a diferença entre o número de isolamentos de unidades formadoras de colônia entre as amostras coletadas no interior do tanque de vinhaça e as amostras de controle. Concluiu-se que o solo do antigo tanque/lagoa avaliado ainda apresenta os efeitos da disposição inadequada de vinhaça, que interfere nas propriedades químicas e microbiológicas do solo / Abstract: The vinasse is an effluent from the ethanol industry, mainly used in fertirrigation of crops of sugar cane. However, several studies indicate that the application and disposal of vinasse on soil cause the contamination by salts and metals, in addition to providing the change of physical, chemical and biological soil properties. The aim of this study was to evaluate the quality of the soil in a vinasse dam without impermeabilization, that was used for 20 years and it's inactive for 8 years. Two boreholes were drilled in the vinasse dam and in a background area at depths of 24 and 32 meters. Soil samples were collected at one meter interval until the depth of the water level. Soil analyses were performed using XRF method to determine the mass fractions of oxides and trace elements, as well as loss on ignition test and microbiological analysis of soil for fungi and yeasts. Also leaching tests were performed with deionized water and nitric acid, and the leachates were analyzed by chromatography and ICP-MS. The results of the soil samples and leach tests indicated that the leaching of soil samples collected inside the vinasse dam showed evidence of salinization compared to control soil samples. The results of the microbiological analyses indicated a difference between the number of isolated colony forming units among samples collected in the vinasse dam and control samples. It was concluded that the soil of the old vinasse dam still shows the effects of improper disposal of vinasse, which interferes with chemical and microbiological properties of the soil / Mestrado / Geologia e Recursos Naturais / Mestra em Geociências
5

The qualitative and quantitative evaluation of estrogen and estrogen-mimicking substances in the South African water environment / Liesl van der Merwe

Van der Merwe, Liesl January 1998 (has links)
Recently some chemicals has been accused of mimicking the female hormone estrogen. The mode of action is termed estrogen-mimicking, because of the effects that is produced by these chemicals. Playing canary in a coal mine, wildlife was the first to indicate that something was wrong. Reproductive abnormalities such as abnormal sperm, reduced sperm production, cryptorchidism (undescended testes). abnormal hormone levels – particularly high estrogen ratios to that of testosterone. infertility, and genital abnormalities were all evidence that something in the environment was affecting the reproductive status of these animals. Also in humans instances like rising cases of infertility, abnormal sperm conditions and cases of breast cancer raised an increased concern about the potential disruptive effects of these substances on the human existence. After investigations were conducted, it was found that substances which enhance the quality of life like some detergents, agricultural products, additives to plastic, dyestuffs, paint components and pharmaceuticals to name but a few, all caused an abnormal reproductive status as seen in animals. The aims of this study were not to focus on the effect of these substances, but rather to identify estrogen and estrogen - mimics in the South African environment and to evaluate their presence in the water environment qualitatively and quantitatively with the most suitable analytical methods. Estrogen - mimics such as nonylphenol. o'p' and p'p' DDE, o'p' DDD, lindane, atrazine and the PCB's : Arochlor 1254 & Arochlor 1260 were found to contaminate the environment. The drinking water tested of the PWV area indicated that the water was free of these substances, and thus indicated a present safe situation. / Thesis (MSc (Farmaseutika))--PU for CHE, 1998
6

Aplicação de testes de toxicidade com organismos marinhos para a análise de efluentes industriais lançados em áreas estuarinas / not available

Prósperi, Valéria Aparecida 17 December 1993 (has links)
Com o objetivo de aplicar e avaliar a viabilidade de uso dos métodos disponíveis com organismos marinhos, no controle da toxicidade de efluentes líquidos que são lançados em ambientes estuarinos, foram realizados testes de toxicidade aguda com os crustáceos Mysidopsis juniae, Artemia sp, Temora stylifera e Acartia IiIljeborgi e testes de toxicidade crônica de curta duração com o equinodermo Lytechinus variegatus, utilizando-se os efluentes industriais de uma indústria siderúrgica, COSIPA e uma fábrica de fertilizantes, ULTRAFÉRTIL/JARDIM SÃO MARCOS, ambos lançados no estuário do Rio Cubatão. Dentre os organismos-testes utilizados, para avaliação do efeito tóxico agudo, o misidáceo M. juniae foi o mais sensível para ambos os efluentes, sendo que Artemia sp foi o menos sensível. Testes de toxicidade crônica com L. variegatus também se mostraram bastante úteis para avaliação de efeitos subletais. Os efluentes analisados apresentaram grande variabilidade durante o período de estudo, o que foi evidenciado através do cálculo do coeficiente de variação para testes com M. juniae. Foi avaliado, também, o efeito da salinidade sobre a sensibilidade dos crustáceos M. juniae e Artemia sp a agentes químicos (zinco e DSS) e aos efluentes industriais. A salinidade não interferiu significativamente nos resultados observados, com exceção de um experimento realizado a 15x10-3 com Artemia sp, com o efluente da COSIPA. Verificou-se, ainda, o possível efeito da utilização de salmoura obtida através dos processos de congelamento e evaporação da água do mar, sendo que o primeiro processo foi indicado para salinização de efluentes. / Acute toxicity tests with the crustaceans Mysidopsis juniae, Anemia sp, Temora stylifera e Acartia lilljeborgi and short-term chronic toxicity test with the echinoderm Lytechinus variegatus were conducted with the objective of evaluating the appropriateness of their application for the control of liquid effluents disposed off in estuarine environments. Effluents of a siderurgic industry, COSIPA, and of a fertilizer plant, ULTRAFÉRTIL/JARDIM SÃO MARCOS, were used. Both are discharged into the estuary of Cubatão river. The test with M. juniae was the most sensitive of the acute methods, for both kinds of effluents, while that with Artemia sp was the least sensitive. Chronic toxicity test with L. variegatus showed to be very useful for the evaluation of sublethal effects. The different effluent samples of both industries had great variability in their toxic effects, along the different sampling periods, as was evidenced by the high coefficient of variation for tests with M. juniae. The effects of salinity on the sensitivity of M. juniae and Artemia sp to chemicals (zinc and DSS) and to the industrial effluents, was evaluated. Salinity did not signifieantly affect the test results, except for the experiment conducted at 15x10-3 with Artemia sp, with the effluent from the siderurgic industry. The possible effect of the use of brine, obtained by freezing or evaporating sea water, was also analyzed. Freezing was the recommended procedure to salinize effluents.
7

"Uso da Tríade como instrumento de avaliação da qualidade do sedimento no entorno do emissário submarino de uma fábrica de celulose" / Use of the Triad Approach to Evaluate Sediment Quality from a Pulp Mill Outfall Area

Furley, Tatiana Heid 08 August 2006 (has links)
Os efluentes de fábricas de celulose são conhecidos por apresentarem uma ampla gama de compostos químicos naturais e antropogênicos, que possuem potencial inibidor e estimulador à biota. Muitos destes podem se agregar ao sedimento e causar efeitos agudos ou crônicos aos organismos. Diversos estudos têm sido realizados para se avaliar a qualidade ambiental do corpo receptor adjacente às fábricas de celulose, entretanto a maioria destes são avaliados de forma isolada, o que dificulta a identificação das áreas realmente afetadas pelo efluente. A abordagem TQS (Tríade de Qualidade dos Sedimentos) integra análises químicas do sedimento, testes de toxicidade e ecologia do bentos. O objetivo do presente trabalho foi avaliar a qualidade dos sedimentos no entorno do emissário de uma fábrica de celulose, através da abordagem TQS. Foram feitas 4 amostragens, em julho e dezembro de 2001 e 2002. O sedimento foi coletado em 9 estações de amostragem, sendo 6 ao redor do emissário da fábrica e 3 afastadas do mesmo (referência). Foram realizadas análises químicas (metais pesados, ácidos graxos, beta sitosterol, EOX, PCBs, N, C, etc.) do sedimento, testes de toxicidade da água intersticial (MICROTOX® e ouriço Echinometra lucunter) e sedimento (anfípodo Tiburonella viscana) e análise da estrutura da comunidade do zoobentos. A análise integrada dos dados da tríade mostrou uma baixa influência do efluente da fábrica na estação de coleta mais próxima do emissário (5) e em duas estações ao sul do mesmo (3 e 7A). A Estação 5 apresentou evidências químicas e toxicológicas de degradação, enquanto que as Estações 3 e 7A apresentaram evidências químicas. / Effluents from pulp mills are known to contain a large number of chemicals that have inhibitory and stimulatory effects on aquatic biota. Many contaminants may adsorb to sediment and cause acute or chronic effects to sediment-dwelling organisms. Several studies have been conducted to evaluate the environmental quality of the receiving body adjacent to a pulp mill (Brazil) outfall. However, most of them were conducted separately, making it difficult to identify the real affected area. The SQT (Sediment Quality Triad) approach integrates chemical analyses of the sediment, toxicity tests and benthic ecology. The purpose of the present study was to evaluate the sediment quality around the outfall of a pulp mill by use of the SQT approach. Samples were collected seasonally over two years, in July and December of 2001 and 2002. The sediment was collected at nine sampling stations, six of them around the outfall and three reference stations located far from the outfall. Several chemical analyses were made (heavy metals, fatty acids, beta sitosterol, EOX, PCBs, N, C) in the sediment, toxicity tests were done with pore water (MICROTOX® and the sea urchin Echinometra lucunter early life stage tests) and sediment (amphipod Tiburonella viscana), and analyses of the structure of the zoobenthic community were performed. The integrated analysis of the SQT data showed some influence, although low, of the effluent on the sampling station closest to the outfall (station 5) and on two stations to the south of the outfall (stations 3 and 7A). Station 5 exhibited evidence of toxicological effects, and stations 5, 3 and 7A exhibited slightly elevated concentrations of chemicals relative to the reference stations.
8

AnSBBR e AnSBR submetidos a diferentes condições de alimentação de água residuária de indústria de produtos de higiene pessoal / AnSBBR and AnSBR submitted to different conditions of wastewater feeding from industry of personal care products

Oliveira, Ricardo Polisaitis 24 April 2009 (has links)
Este trabalho apresenta a avaliação da estabilidade e da eficiência de dois reatores anaeróbios operados em batelada seqüencial no tratamento de água residuária que simula o efluente de indústria de produtos de higiene pessoal, sendo um com biomassa imobilizada em espuma de poliuretano (AnSBBR) e recirculação da fase líquida, e outro com biomassa granular autoimobilizada (AnSBR) e agitação mecânica. O AnSBBR foi operado em batelada e em batelada alimentada, seguida de batelada, com tempo de ciclo (tc) de 8 h e carga orgânica volumétrica aplicada (COVA) de 0,9 e 1,5 gDQO/L.d, tratando 2,5 L de meio líquido por ciclo. Os valores de eficiência de remoção de matéria orgânica de amostras filtradas do efluente ficaram abaixo de 71% nas condições operadas em batelada, e acima de 74% nas condições operadas em batelada alimentada, seguida de batelada. Por outro lado, o AnSBR foi operado em batelada, com tc de 8, 12 e 24 h e COVA de 0,75, 0,50 e 0,25 gDQO/L.d, tratando 2,0 L de meio líquido por ciclo. O aumento de tc resultou em ganho de eficiência nas condições de mesma COVA, chegando a 77% para tc de 24 h, contra 69% para tc de 8 h. Porém, houve queda de eficiência nas condições em que a COVA foi reduzida em função do aumento de tc. / This study presents the evaluation of stability and efficiency of two anaerobic sequencing batch reactors for wastewater treatment simulating the effluent from industry of personal care products, one containing immobilized biomass on polyurethane foam (AnSBBR) and external circulation of the liquid phase, and the other with self-immobilized granulated biomass (AnSBR) and mechanical agitation. The AnSBBR was operated in batch and fed batch/batch modes, with cycle time (tc) of 8 h and applied organic loading rates (COVA) of 0.9 and 1.5 gDQO/L.d, treating 2.5 L of liquid medium per cycle. The values of organic matter removal efficiency for filtered samples of effluent were below 71% in batch operations, and over 74% in fed-batch/batch operations. On the other hand, the AnSBR was operated in batch, with tc of 8, 12 and 24 h and COVA of 0.75, 0.50 and 0.25 gDQO/L.d, treating 2.0 L of liquid medium per cycle. The increase of tc resulted in higher values of efficiency for conditions with the same COVA, reaching 77% for a 24-h cycle against 69% for an 8-h cycle. However, there was an efficiency drop at the conditions in which COVA was reduced due to an increase of tc.
9

The qualitative and quantitative evaluation of estrogen and estrogen-mimicking substances in the South African water environment / Liesl van der Merwe

Van der Merwe, L. (Liesl) January 1998 (has links)
Thesis (MSc (Farmaseutika))--PU for CHE, 1998.
10

The qualitative and quantitative evaluation of estrogen and estrogen-mimicking substances in the South African water environment / Liesl van der Merwe

Van der Merwe, Liesl January 1998 (has links)
Recently some chemicals has been accused of mimicking the female hormone estrogen. The mode of action is termed estrogen-mimicking, because of the effects that is produced by these chemicals. Playing canary in a coal mine, wildlife was the first to indicate that something was wrong. Reproductive abnormalities such as abnormal sperm, reduced sperm production, cryptorchidism (undescended testes). abnormal hormone levels – particularly high estrogen ratios to that of testosterone. infertility, and genital abnormalities were all evidence that something in the environment was affecting the reproductive status of these animals. Also in humans instances like rising cases of infertility, abnormal sperm conditions and cases of breast cancer raised an increased concern about the potential disruptive effects of these substances on the human existence. After investigations were conducted, it was found that substances which enhance the quality of life like some detergents, agricultural products, additives to plastic, dyestuffs, paint components and pharmaceuticals to name but a few, all caused an abnormal reproductive status as seen in animals. The aims of this study were not to focus on the effect of these substances, but rather to identify estrogen and estrogen - mimics in the South African environment and to evaluate their presence in the water environment qualitatively and quantitatively with the most suitable analytical methods. Estrogen - mimics such as nonylphenol. o'p' and p'p' DDE, o'p' DDD, lindane, atrazine and the PCB's : Arochlor 1254 & Arochlor 1260 were found to contaminate the environment. The drinking water tested of the PWV area indicated that the water was free of these substances, and thus indicated a present safe situation. / Thesis (MSc (Farmaseutika))--PU for CHE, 1998

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