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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.
411

Clinical waste management and its future development in Hong Kong

Tam, Yiu-man., 譚耀敏. January 1996 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
412

Management, disposal and recycling of waste organic solvents in Hong Kong

Lau, Kin-wah., 劉健華. January 1998 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
413

Estudo de viabilidade técnica econômica para implementação de uma unidade móvel para tratamento de efluentes industriais com feixe de elétrons / Study of technical and economical feasibility for implementation of a movable unit for treatment of industrial effluents with electron beam

Rela, Carolina Sciamarelli 21 November 2006 (has links)
O tratamento de efluentes industriais é uma prática que vem se disseminando em ritmo acelerado, porque além de contribuir para reforçar a imagem pública, através do combate à poluição, ela traz vantagens econômicas para as empresas que podem reutilizar a água tratada do efluente em seus próprios processos. A técnica de tratamento estudada no presente trabalho é a que utiliza a oxidação/redução química destacando-se a utilização da radiação ionizante por meio de feixes de elétrons. Esta técnica utiliza um processo oxidativo avançado, gerando radicais altamente reativos que provocam a oxidação, redução, dissociação e degradação em compostos orgânicos e exercendo efeito letal nos microorganismos, protozoários e parasitas em geral. Neste trabalho desenvolveu-se um projeto conceituai e básico de uma unidade móvel de tratamento de efluentes utilizando radiação ionizante, fazendo com que a unidade se desloque até o ponto de tratamento, facilitando assim a logística. Em seguida, elaborou-se um estudo de viabilidade técnica e econômica permitindo dados consistentes sobre a capacidade e custo de processamento de efluentes e valores consolidados dos investimentos necessários para serem apresentados a órgãos financiadores para a construção de uma unidade móvel. Os resultados dos estudos demonstram que é viável tecnicamente a construção de uma unidade móvel, pois atende a legislação pertinente do Brasil, nos aspectos de Radioproteção e limite de transporte de carga. O custo unitário do processamento mostrou-se superior ao de uma unidade fixa em razão da diminuição da eficiência da interação da radiação incidente no efluente processado, devido à redução de energia do acelerador de elétrons e da disponibilidade de operação da unidade. / The treatment of industrial effluents is a practice that is disseminating in accelerated rhythm, of contributing to reinforce the public image, through the combat of the pollution, it brings economical advantages allowing the companies the reuse of the treated water in their own processes. The liquid effluent treatment technique studied in the present work is the one that uses the chemical oxidation/reduction standing out the use of the electron beam (e.b.) radiation. This technique uses an advanced oxidation process, generating radicals highly reagents that provoke the oxidation, reduction, dissociation and degradation in composed organic and exercising lethal effect in general in the microorganisms and parasites. In this work a conceptual and basic project of a movable unit of effluents treatment using electron beam radiation process was developed, in order that the unit moves until the treatment point, where the effluent is produced, facilitating the logistics. A technical and economical feasibility study was also elaborated allowing data on the capacity and cost of effluents processing to consolidate the values of the necessary investments to be presented to foundations organs for the construction of a movable unit. The results of the studies demonstrated that it is technically viable attending the pertinent legislation of Brazil, in the aspects of Radiation Protection and transport limit capacity. The unitary cost of the e.b. radiation processing in the movable unit was shown more expensive than in the fixed unit, the reason is the decrease of the efficiency of the interaction of the incident electrons in the effluent, due to the reduction of electron energy operation time of the unit.
414

Tertiary biovalorisation of Grape pomace

Angadam, Justine Oma January 2018 (has links)
Thesis (Masters of Environmental Health)--Cape Peninsula University of Technology, 2018. / In the Western Cape, South Africa and other regions globally, grape pomace (GP) is one of the abundant agro-waste from the winery industry. This study reports on the hyper-extraction of fermentable sugars from GP treated with white rot fungi (WRF) Phanerochaete chrysosporium BKMF 1767 to facilitate improved biovalorisation for total reducing sugars (TRS) extraction in conjunction with Nepenthes mirabilis digestive fluids. TRS were quantified using the 3,5-dinitrosalicylic acid (DNS) reagent method. The free readily dissolvable sugars from the GP recorded for the bio-treated (BT) samples was 206.39 ± 0.06 mg/L and for the untreated (UT) samples was 271.05 ± 0.02 mg/L. Overall, the TRS yield for the Bio-treated (BT) and untreated (UT) samples was recorded as 205.68 ± 0.09 and 380.93 ± 0.14 mg/L, respectively, using hot water pretreatment (HWP) with 2266.00 ± 0.73 (BT) and 2850.68 ± 0.31 mg/L (UT), respectively, for dilute acid pretreatment (DAP); with 2068.49 ± 6.02 (BT) and 2969.61 ± 8.054 mg/L (UT) respectively, using the cellulase pretreatment (CP) method. Using the HWP as a reference, the relative increases imparted by the biotreatment was higher (51%) for DAP and low (33%) for CP. The combination of conventional used pre-treatment methods (hot water pretreatment, dilute acid pre-treatment, and cellulase pre-treatment) in a single pot system was also done while monitoring the total residual phenolics (TRPCs) in the samples. Furthermore, powder X-ray diffraction (pXRD) were used to measure the crystallinity index (CrI) and functional groups of pre- and post-pretreated GP to ascertain the efficiency of the pre-treatment methods, with quantification of lignin, holocellulose, and ash. Overall, the TRS yield for N. mirabilis pre-treated agro-waste was 951 mg/L ± 4.666 mg/L, with biomass having a lower CrI of 33%, and 62% residual lignin content. Furthermore, reduced TRPCs were observed in hydrolysate, suggesting limited inhibitory by-product formation during N. mirabilis pre-treatment
415

Estudo de viabilidade técnica econômica para implementação de uma unidade móvel para tratamento de efluentes industriais com feixe de elétrons / Study of technical and economical feasibility for implementation of a movable unit for treatment of industrial effluents with electron beam

Carolina Sciamarelli Rela 21 November 2006 (has links)
O tratamento de efluentes industriais é uma prática que vem se disseminando em ritmo acelerado, porque além de contribuir para reforçar a imagem pública, através do combate à poluição, ela traz vantagens econômicas para as empresas que podem reutilizar a água tratada do efluente em seus próprios processos. A técnica de tratamento estudada no presente trabalho é a que utiliza a oxidação/redução química destacando-se a utilização da radiação ionizante por meio de feixes de elétrons. Esta técnica utiliza um processo oxidativo avançado, gerando radicais altamente reativos que provocam a oxidação, redução, dissociação e degradação em compostos orgânicos e exercendo efeito letal nos microorganismos, protozoários e parasitas em geral. Neste trabalho desenvolveu-se um projeto conceituai e básico de uma unidade móvel de tratamento de efluentes utilizando radiação ionizante, fazendo com que a unidade se desloque até o ponto de tratamento, facilitando assim a logística. Em seguida, elaborou-se um estudo de viabilidade técnica e econômica permitindo dados consistentes sobre a capacidade e custo de processamento de efluentes e valores consolidados dos investimentos necessários para serem apresentados a órgãos financiadores para a construção de uma unidade móvel. Os resultados dos estudos demonstram que é viável tecnicamente a construção de uma unidade móvel, pois atende a legislação pertinente do Brasil, nos aspectos de Radioproteção e limite de transporte de carga. O custo unitário do processamento mostrou-se superior ao de uma unidade fixa em razão da diminuição da eficiência da interação da radiação incidente no efluente processado, devido à redução de energia do acelerador de elétrons e da disponibilidade de operação da unidade. / The treatment of industrial effluents is a practice that is disseminating in accelerated rhythm, of contributing to reinforce the public image, through the combat of the pollution, it brings economical advantages allowing the companies the reuse of the treated water in their own processes. The liquid effluent treatment technique studied in the present work is the one that uses the chemical oxidation/reduction standing out the use of the electron beam (e.b.) radiation. This technique uses an advanced oxidation process, generating radicals highly reagents that provoke the oxidation, reduction, dissociation and degradation in composed organic and exercising lethal effect in general in the microorganisms and parasites. In this work a conceptual and basic project of a movable unit of effluents treatment using electron beam radiation process was developed, in order that the unit moves until the treatment point, where the effluent is produced, facilitating the logistics. A technical and economical feasibility study was also elaborated allowing data on the capacity and cost of effluents processing to consolidate the values of the necessary investments to be presented to foundations organs for the construction of a movable unit. The results of the studies demonstrated that it is technically viable attending the pertinent legislation of Brazil, in the aspects of Radiation Protection and transport limit capacity. The unitary cost of the e.b. radiation processing in the movable unit was shown more expensive than in the fixed unit, the reason is the decrease of the efficiency of the interaction of the incident electrons in the effluent, due to the reduction of electron energy operation time of the unit.
416

Panorama dos resíduos sólidos industriais e de mineração do estado de Goiás / Overview of industrial and mining solid waste in the state of Goiás

Oliveira, Adjane Damasceno de 22 September 2015 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-02-05T12:16:50Z No. of bitstreams: 2 Dissertação - Adjane Damasceno de Oliveira - 2015.pdf: 2360434 bytes, checksum: 99290688ce09cf90c2e693539b971b50 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-02-05T12:18:45Z (GMT) No. of bitstreams: 2 Dissertação - Adjane Damasceno de Oliveira - 2015.pdf: 2360434 bytes, checksum: 99290688ce09cf90c2e693539b971b50 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-02-05T12:18:45Z (GMT). No. of bitstreams: 2 Dissertação - Adjane Damasceno de Oliveira - 2015.pdf: 2360434 bytes, checksum: 99290688ce09cf90c2e693539b971b50 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-09-22 / The increase the state of Goiás should come accompanied of a administration that look for the balance between economic, social and environmental sectors, In this last, it is included an appropriate management of solid waste generate at the territory. In this study was elaborated an overview of the current situation of industrial and mining solid waste, contributing directly to supply the lack of data that subsidize the elaboration of policies that strengthen the guidelines of administration in Goiás, and also contribute with the proposition of mechanisms to structure the state information system of solid waste. For this, information was collected in several databases, official (Department of the Environment, infrastructure, Cities and Metropolitan Issues, State Treasury Office, National Department of Mineral Research) and non-official (Goiás Federation of Industries) databases and a primary data collection system has been developed so that the information was as close to reality as possible. The databases accessed was compared and analyzed. To carry out the review of waste destinations was necessary some adjustment and revaluation of the coding used in the process that received these wastes. Even with the establishment of a mechanism with closed answers, it was still necessary to evaluate what was declared to carry out an overview that matches to the reality. After the data compilation, it was possible to establish results of estimative for the generation, composition and disposal of industrial and mining waste in the State of Goiás. A comparison with these results with the 2001 inventory data was carried out, and to complete the state overview, the data of the authorizations for the waste entries in the state of Goiás issued in 2013 were collected. Finally, there was an analysis of the strategic areas for installation of industrial waste centers within the state territory. According to the results obtained were estimated one generation of 8.481.680 tons of industrial waste and 10.781.011 tons of mining waste. As the destination, the destination for another forms of reuse and recycling was the most representative with almost 38% from the total of industrial waste generated, whereas, the largest portion of the mining waste was destined to landfills of the own generators of waste, approximately 75% of the total. This study demonstrated that one of the difficulties encountered in collecting information is to perform the inventory data involving the largest number of possible waste generators and allow to conclude that the results found until the time can`t be considerate satisfactory, but make a landmark for the consolidation of solid waste data collected in Goiás. Therefore it is important to promote more comprehensive training throughout the territory and the establishment of mandatory participation in data reporting. In addition, it is essential that the States and Union work together so that the databases can be compatible to the point that they can be manipulated and can produce reliable results. / O crescimento do Estado de Goiás deve vir acompanhado de uma gestão que busque equilíbrio entre os setores, econômico, social e ambiental. Neste último, inclui-se a gestão adequada dos resíduos gerados no território estadual. Neste estudo buscou-se a elaboração de um panorama da atual situação dos resíduos sólidos industriais e de mineração, contribuindo diretamente para suprir a ausência de dados que subsidiam a elaboração de políticas que fortaleçam as diretrizes de gestão para Goiás, além de cooperar com a proposição de mecanismos para estruturar o sistema de informação estadual de resíduos sólidos. Para tal, buscou-se informações em diversos bancos de dados, oficiais (Secretaria de Meio Ambiente, Recursos Hídricos, Infraestrutura, Cidades, Assuntos Metropolitanos, Secretaria da Fazenda, Departamento Nacional de Pesquisa Mineral) e não oficiais (Federação das Indústrias do Estado de Goiás), e foi desenvolvido mecanismo de coleta de dados primários para que as informações estivessem o mais próximo possível da realidade. Os bancos de dados acessados foram comparados e os dados foram organizados e analisados. Para realizar o levantamento das destinações foram necessárias algumas adaptações e reavaliações da codificação usada nos processos que receberam estes resíduos. Mesmo com o estabelecimento de um mecanismo com respostas fechadas ainda assim foi necessário avaliar o que foi declarado para realizar um diagnóstico que correspondesse à realidade. Após compilação dos dados foi possível estabelecer resultados referentes às estimativas de geração com base em tipologia das atividades e porte dos empreendimentos e destinação dos resíduos industriais e de mineração no Estado de Goiás. Realizou-se a comparação com os dados obtidos no inventário de 2001 e, para completar o panorama estadual, foram levantados dados referentes as autorizações de destinação de resíduos no Estado emitidas no ano de 2013. Por fim, fez-se uma análise das regiões estratégicas para instalação de pólos industriais de resíduos dentro do território estadual. De acordo com os resultados obtidos, foram estimadas uma geração de 8.481.680 toneladas de resíduos industriais e 10.781.011 toneladas de resíduos de mineração no Estado de Goiás para o ano de 2013. Quanto a destinação, para os resíduos industriais a destinação para outras formas de reutilização, reciclagem, recuperação, dentre elas incorporação em outros processos industriais foi a mais representativa com quase 38% do total e para os resíduos de mineração a maior parcela foi destinada para aterros dos próprios geradores representando cerca de 75% do total. Este trabalho demonstrou que uma das dificuldades encontradas no levantamento de informações é realizar a inventariação de dados que envolva o maior número de geradores de resíduos possível o que permite concluir que os resultados encontrados até o momento não podem ser considerados satisfatórios, mas já estabelece um marco na consolidação na inventariação de resíduos no Estado. Conclui-se que é importante promover treinamentos mais abrangentes ao longo do território e o estabelecimento de caráter obrigatório de participação na declaração de dados. Além disso, é essencial que os Estados e União trabalhem em conjunto para que os bancos de dados sejam compatíveis permitindo que possam ser manipulados de maneira eficiente e produzam resultados confiáveis. Concluir
417

Clínquer Coprocessado: Produto de Tecnologia Integrada para Sustentabilidade e Competitividade da Indústria de Cimento / Co-processed Clinker: Integrated Technology Product for the Cement Industry Sustainability and Competitiveness

Vagner Maríngolo 08 August 2001 (has links)
Em agosto de 2001 havia, no Brasil, sete fábricas de cimento com licença para o co-processamento de resíduos industriais em seus fornos, em substituição à matriz energética, e 14 outras em vias de adquiri-la. Há mais de cinco anos, a Companhia de Cimento Ribeirão Grande conta com efetiva participação de uma mistura (blend) de resíduos industriais de diferentes correntes no processo. O clínquer co-processado é hoje o componente principal do cimento portland da fábrica, o qual manteve resistências mecânicas à compressão às idades de 1, 3, 7 e 28 dias sempre acima dos limites normativos mínimos exigidos. Para atestar a imobilidade dos componentes inorgânicos incorporados ao clínquer, utilizaram-se ensaios microscópicos e análises químicas por espectrometria de absorção atômica e de raios X em clínqueres industriais não co-processados e co-processados; testes de lixiviação em cimentos de laboratório; química mineral por microssonda eletrônica e microscopia eletrônica de varredura em clínqueres dopados com Zn, V e Pb. Os resultados levaram, em linhas gerais, às seguintes considerações: - A microestrutura dos clínqueres co-processados manteve-se preservada com a introdução do blend no sistema. - As matérias-primas e o combustível fóssil respondem por boa parte dos elementos traços presentes no sistema. O blend introduz aporte extra dos elementos traços presentes na composição, enriquecendo seletivamente o clínquer co-processado. - Há, de maneira geral, compatibilidade grande dos elementos traços com o clínquer, mesmo de elementos voláteis como cádmio e mercúrio. Já cobalto e, principalmente, chumbo, são os que se mostraram menos compatíveis. - Nos clínqueres experimentais, alita incorporou preferencialmente zinco e chumbo, e belita, vanádio. - Não houve solubilização significativa de nenhum elemento de relevância ambiental dos cimentos, atestando sua retenção nos retículos cristalinos dos minerais formadores do clínquer portland. A qualidade ambiental do clínquer portland co-processado deve abranger sua propriedade de reter elementos traços em solução sólida, a manutenção da integridade das relações texturais, e a garantia da imobilidade de componentes tóxicos no produto final, através de um controle sistemático dos clínqueres e também dos cimentos. / In August 2001, in Brazil, there were seven cement plants with and an increasing number of others on the way to get the permit to co-processing, i.e. burning industrial wastes in their kilns as substitutes for fossil fuels. For over five years now the Companhia de Cimento Ribeirão Grande has counted on partial substitution of a blend of different waste streams for fossil fuels in the burning process. Co-processed clinker makes up today the main component of their Portland cement, which has shown mechanical strengths at 1, 3, 7 and 28 days permanently above standardized minimal limits. In order to assess the immobility of trace elements incorporated to the clinkers, a methodology was used which comprised carrying out microscopy and chemical analysis by atomic absorption and X-ray spectrometry of both conventional and co-processed clinkers, leaching tests on laboratory cements prepared with co-processed clinkers, mineral chemistry by electronic microprobe and scanning electronic microscopy on experimental clinkers doped with Zn, V and Pb. The results led to the following general statements: - Co-processed clinkers showed sound microstructure just like conventional clinkers. - Raw materials – limestone, clay and iron ore – and fossil fuels account a great deal for the amounts of trace elements involved in the burning process. According to its composition, the blend enriches selectively co-processed clinkers. - A general compatibility of trace elements – even highly volatile ones such as Cd and Hg – in clinker was observed. Co and especially Pb, however, were comparatively incompatible. - Alite of experimental clinkers incorporated preferentially Zn and Pb while belite incorporated V. - No elements showed any significant solubility from laboratory cements, thus attesting retention of environmentally relevant trace elements in the crystal lattice of clinker mineral phases. Co-processed Portland clinker must present environmental quality by retaining trace elements in solid solution, while being able to keep sound textural relationships, and guarantee immobility of toxic components on the final product. This should be attested through a systematic control of clinkers and also of cements.
418

Clínquer Coprocessado: Produto de Tecnologia Integrada para Sustentabilidade e Competitividade da Indústria de Cimento / Co-processed Clinker: Integrated Technology Product for the Cement Industry Sustainability and Competitiveness

Maríngolo, Vagner 08 August 2001 (has links)
Em agosto de 2001 havia, no Brasil, sete fábricas de cimento com licença para o co-processamento de resíduos industriais em seus fornos, em substituição à matriz energética, e 14 outras em vias de adquiri-la. Há mais de cinco anos, a Companhia de Cimento Ribeirão Grande conta com efetiva participação de uma mistura (blend) de resíduos industriais de diferentes correntes no processo. O clínquer co-processado é hoje o componente principal do cimento portland da fábrica, o qual manteve resistências mecânicas à compressão às idades de 1, 3, 7 e 28 dias sempre acima dos limites normativos mínimos exigidos. Para atestar a imobilidade dos componentes inorgânicos incorporados ao clínquer, utilizaram-se ensaios microscópicos e análises químicas por espectrometria de absorção atômica e de raios X em clínqueres industriais não co-processados e co-processados; testes de lixiviação em cimentos de laboratório; química mineral por microssonda eletrônica e microscopia eletrônica de varredura em clínqueres dopados com Zn, V e Pb. Os resultados levaram, em linhas gerais, às seguintes considerações: - A microestrutura dos clínqueres co-processados manteve-se preservada com a introdução do blend no sistema. - As matérias-primas e o combustível fóssil respondem por boa parte dos elementos traços presentes no sistema. O blend introduz aporte extra dos elementos traços presentes na composição, enriquecendo seletivamente o clínquer co-processado. - Há, de maneira geral, compatibilidade grande dos elementos traços com o clínquer, mesmo de elementos voláteis como cádmio e mercúrio. Já cobalto e, principalmente, chumbo, são os que se mostraram menos compatíveis. - Nos clínqueres experimentais, alita incorporou preferencialmente zinco e chumbo, e belita, vanádio. - Não houve solubilização significativa de nenhum elemento de relevância ambiental dos cimentos, atestando sua retenção nos retículos cristalinos dos minerais formadores do clínquer portland. A qualidade ambiental do clínquer portland co-processado deve abranger sua propriedade de reter elementos traços em solução sólida, a manutenção da integridade das relações texturais, e a garantia da imobilidade de componentes tóxicos no produto final, através de um controle sistemático dos clínqueres e também dos cimentos. / In August 2001, in Brazil, there were seven cement plants with and an increasing number of others on the way to get the permit to co-processing, i.e. burning industrial wastes in their kilns as substitutes for fossil fuels. For over five years now the Companhia de Cimento Ribeirão Grande has counted on partial substitution of a blend of different waste streams for fossil fuels in the burning process. Co-processed clinker makes up today the main component of their Portland cement, which has shown mechanical strengths at 1, 3, 7 and 28 days permanently above standardized minimal limits. In order to assess the immobility of trace elements incorporated to the clinkers, a methodology was used which comprised carrying out microscopy and chemical analysis by atomic absorption and X-ray spectrometry of both conventional and co-processed clinkers, leaching tests on laboratory cements prepared with co-processed clinkers, mineral chemistry by electronic microprobe and scanning electronic microscopy on experimental clinkers doped with Zn, V and Pb. The results led to the following general statements: - Co-processed clinkers showed sound microstructure just like conventional clinkers. - Raw materials – limestone, clay and iron ore – and fossil fuels account a great deal for the amounts of trace elements involved in the burning process. According to its composition, the blend enriches selectively co-processed clinkers. - A general compatibility of trace elements – even highly volatile ones such as Cd and Hg – in clinker was observed. Co and especially Pb, however, were comparatively incompatible. - Alite of experimental clinkers incorporated preferentially Zn and Pb while belite incorporated V. - No elements showed any significant solubility from laboratory cements, thus attesting retention of environmentally relevant trace elements in the crystal lattice of clinker mineral phases. Co-processed Portland clinker must present environmental quality by retaining trace elements in solid solution, while being able to keep sound textural relationships, and guarantee immobility of toxic components on the final product. This should be attested through a systematic control of clinkers and also of cements.
419

Use of lean and building information modeling (bim) in the construction process; does bim make it leaner?

Ningappa, Geetanjali Ningappa 08 April 2011 (has links)
Construction productivity lags behind most industries. In general, the process of construction is carried out in several smaller processes. For the overall construction process to be successful, continuity between these smaller processes must be achieved. This has been the persistent goal of construction productivity improvement for decades now. Waste is generated between the continuing activities by the unpredicted release of work and the arrival of resources. However, in recent decades the construction industry has a great need to improve its productivity, quality and incorporate new technologies to the industry due to increased foreign competition. In the late 1980s, researchers started looking at solving this problem in a more general and structured way based on the philosophy and ideology of lean production. In lean, adopting waste identification/reduction, or meeting the client's needs with minimal resources addresses the performance improvement. With recent developments in the construction industry, introduction of building information modeling (BIM) has had a significant influence on leaner construction. They are both complementary in several important ways. Various studies conducted exhibit that BIM is very crucial in reducing the project cost, site conflicts, project duration, error reduction, better and faster design development, and so on. This brings the question; can BIM be used as a tool for leaner construction? The objective of this thesis is to determine how BIM is helping achieve a leaner construction. More and more companies are adopting BIM as an acceptable waste reduction tool. A comprehensive study of lean theory and BIM was conducted, underscoring ways for BIM to help achieve leaner construction. The research was broadly conducted in three different parts. In the first part, a synthesis is drawn from a literature study to show that BIM helps reduce waste, helps in implementing lean techniques, and achieves lean principles. The second part focuses on the data acquired from a construction company to show that BIM helps reduce project cost, duration and conflicts. The third and the last part focused on getting the perspective view of different professionals in the construction industry on BIM by conducting focus interviews. A comprehensive conclusion was derived based on the findings from the three methods adopted.
420

An assessment of waste management practices in South Africa : a case study of Mariannhill landfill site, eThekwini Municipality.

January 2009 (has links)
A number of environmental, social and economic problems are associated with waste disposal in landfill operations. The potential hazards associated with landfill operations are numerous and include fatal accidents, infrastructure damage, pollution of the local environment, harmful air emissions, to simple nuisance problems – such as dust, odour, vermin, and noise pollution. Further challenges include the availability of land and lack of municipal or other financing in the face of rising operation costs. Landfilling is, however, seen by many as an environmentally responsible and cost-effective solution to waste disposal. It is acknowledged however to lead to waste of resources by burying valuable materials that could have been reutilized. Careful engineering can resolve this shortcoming, yet the associated challenges and costs can become prohibitive. The regulatory environment also affects the prospects for adopting this approach to landfill site management in different contexts. The Mariannhill landfill site in eThekwini Municipality, South Africa, provides an opportunity to investigate both the range of challenges which these type of sites encounter, and the solutions which have been developed as a response. The central questions which this research seeks to answer are whether the practices adopted by the Mariannhill landfill site are replicable in other solid waste landfills around eThekwini and whether it can be viewed as an example of best practice in landfill site management more generally. The research finds that the main barrier to easy replication of systems followed at Mariannhill in other landfill sites is the difficulty in replicating the specific structures and character of management. Another key determining factor found is the prevailing attitudes to recycling and the environment in general in the society. Consumers choices are seen to be critical to the prospects for recycling of solid waste, including the size, degradability and recyclable potential of products purchased. In considering the potential for replication of the Mariannhill model as an example of best practice, it becomes clear that the technical aspects of operations at Mariannhill are the most easily replicable, yet other and equally important determinants of success are not easily replicable. These include the existing regulatory environment and prevailing societal attitudes towards recycling. / Thesis (M.T.R.P.)-University of KwaZulu-Natal, Durban, 2009.

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