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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.
91

MATERIAL EFFICIENCY MANAGEMENT IN MANUFACTURING

Shahbazi, Sasha January 2015 (has links)
Material efficiency is a key solution to provide a reduction in the total environmental impact of global manufacturing, which contributes to avoid generating larger volumes of industrial waste, to reduce extracting and consuming ever more resources and to decrease energy demand and carbon emissions. However, the area of material efficiency in manufacturing has been under-researched and related knowledge is limited. The research objective of this thesis is to contribute to the existing body of knowledge regarding material efficiency in manufacturing - to increase understanding, describe the existing situation and develop support for improvement. This thesis focuses on value of process and residual materials in material efficiency: to increase homogenous quality of generated waste with higher segregation rate, decreasing the amount of material becoming waste and reduce total virgin raw material consumption without influencing the function and quality of a product or process. To achieve the objective, material efficiency strategies, existing state of material efficiency in manufacturing and barriers that avert higher material efficiency improvement have been investigated. The results are supported by four structured literature reviews and two [MW1] empirical multiple case studies at large global manufacturing companies in Sweden, mainly automotive. Empirical studies include observations, interviews, waste stream mapping, waste sorting analysis, environmental report reviews and walkthroughs in companies to determine the material efficiency and industrial waste management systems. The empirical results revealed that material efficiency improvement potential of further waste segregation to gain economic and environmental benefits is still high. Determining different waste segments and relative fractions along with calculating material efficiency performance measurements facilitate improvements in material efficiency. In addition to attempts for waste generation reduction, avoiding blending and correct segregation of different waste fractions is an essential step towards material efficiency. The next step is to improve the value of waste fractions i.e. having more specific cost-effective fractions. Waste Flow Mapping proves to be an effective practical tool to be utilized at manufacturing companies in order to check and explore the improvement opportunities. In addition, a number of barriers that hinder material efficiency was identified. The most influential material efficiency barriers are Budgetary, Information, Management and Employees. The majority of identified material efficiency barriers are internal, originate inside the company itself and are dependent upon the manufacturing companies’ characteristics. As a result, management and employees’ attitude, environmental knowledge and environmental motivation, as well as their internal communication and information sharing, and companies’ core value and vision are the enablers for material efficiency improvement. / MEMIMAN / INNOFACTURE - innovative manufacturing development
92

Impacts of dried Athel leaves and silica fume as eco-friendly wastes on behaviour of lime-treated heavy clay

Muhmed, Asma A.B. January 2021 (has links)
Construction on problematic soils is challenging owing to the potential of volume changes due to variation of moisture content. Lime stabilisation can be used to treat problematic soils. The main drawbacks of lime addition to the clayey soils are the need for lengthy curing periods and relatively large quantities of lime for significant improvement and also loss in ductility. Using eco-friendly agricultural and industrial wastes, that can partially be substituted by the material responsible for greenhouse gases such as lime, can overcome these drawbacks and decrease global warming. In the current study, variables controlling the unconfined compressive strength of lime treated clay with a focus on assessing the effects of moisture content were investigated. Furthermore, the effects of adding agricultural waste (Dried Athel Leaves (DAL)) and industrial waste (Silica Fume (SF)) on hydromechanical properties of lime treated clay were assessed. The performance of the treated mixtures was examined based on results attained from unconfined compressive strength, swelling pressure and permeability. Specimens were treated with deferent percentages of lime and cured at different periods and temperatures to observe the strength behaviour. In oedometer tests, the specimens were prepared and tested immediately after compaction. The failure patterns were also studied to better understand the ultimate behaviour of lime stabilised clays. The appearance and presence of cementitious products were identified by using the scanning electron microscope and energy dispersive X-ray spectrometer techniques to elucidate their strength development. The findings indicated that the effect of moisture content is controlled by the clay content and unit weight. The addition of 7% lime to clay caused a remarkable increase in the unconfined compressive strength by 363%. The incorporation of 2% DAL and 5% SF within lime treated clay further increased the strength by 6% and 33% respectively after curing of 28 days at 20 °c in comparison with those attained by lime treatment only. The improvement of the strength of the lime­ treated clay augmented with both wastes continued in long term. Temperature and lime content have positive effects on the improvement of strength, however, increasing lime content to 11% negatively affected the strength of lime treated specimens with 2% DAL. The formation of cementitious products was observed in SEM images and detected quantitatively through EDS analysis. The results of the recorded oedometric tests for lime-DAL and lime-SF mixtures revealed that incorporation of the 2% DAL and 5% SF reduced the clay swelling pressures by 25% and 10% compared to that attained by lime treatment only resulting in total reductions of 93.6% and 68% from that recorded on untreated clay. In addition, the impermeable clay transformed into permeable material by adding DAL and SF. Of the two types of wastes considered in this research, DAL demonstrated more superior improving capability. A further study was conducted to develop ANN model based on collated laboratory data for the prediction of the UCS values of lime treated soils. The promising outcomes of this research suggest that the drawbacks of lime stabilisation can be overcome by the addition of agricultural and industrial wastes. Consequently, the findings attained could be considered in future practice standards with regards to the requirement of lime stabilisation. / Ministry of Higher Education and Scientific Research in Libya
93

Desenvolvimento e caracterização de placas poliméricas produzidas a partir da reciclagem do resíduo industrial de poliuretana termofixa / Development and characterization of polymeric plates produced from the recycling of industrial waste thermoset polyurethane.

Baldan, Victor José dos Santos 25 February 2015 (has links)
Os compósitos são materiais formados por duas fases de diferentes propriedades químicas e físicas, sendo uma matriz e um reforço, que apresentam alta rigidez, melhores respostas à fadiga sob cargas cíclicas, leveza e resistência mecânica, o que os torna viáveis para substituir materiais nobres e de custo elevado, com diversas aplicações na aeronáutica, nos esportes, na indústria bélica e principalmente na construção civil. Além disso, os compósitos podem ser obtidos a partir da incorporação de resíduos em sua composição, solucionando problemas como o descarte irregular. Com o intuito de contribuir nessa área de conhecimento o presente estudo propôs o desenvolvimento de um compósito em forma de placas poliméricas a partir da incorporação do agregado reciclado de poliuretana termofixa reciclado à resina vegetal de mamona e à mantas de fibra de vidro. Para isso, o trabalho estabeleceu uma metodologia na qual o resíduo industrial de poliuretana termofixa é transformado em agregado reciclado, a partir de processos de corte e moagem, caracterização e classificação segundo as normas NBR 10.004 a 10.007 (ABNT, 2004). Na sequência, com o auxílio de uma prensa térmica, foi possível confeccionar as placas poliméricas e caracterizálas quanto às suas propriedades mecânicas (tração, flexão, punção), físicas (absorção em água, inchamento, densidade e dureza), térmicas (condutividade térmica) e quanto ao seu potencial de durabilidade (resistência ao impacto, à abrasão superficial, ao ataque químico, à exposição ao ultravioleta e às intempéries, resistividade elétrica e flamabilidade). Os resultados obtidos por meio dos ensaios realizados apontaram que os parâmetros ensaiados comportaram-se como materiais semelhantes àqueles utilizados na construção civil, o que possibilita a utilização do material desenvolvido nesta pesquisa em aplicações por este setor. / This study proposes the development of a composite material in the form of polymer slabs. The material is created from the incorporation of recycled thermoset polyurethane to castor oil resin and glass fiber mats. Composite materials are formed by two phases with different chemical and physical properties. One phase is a matrix, and the other a reinforcement. These materials are highly stiff, light, have mechanical strength and present better responses to fatigue under cyclic loads. These properties make them a substitute for noble materials, being eligible for uses in aviation, sports, the arms industry and, specially, civil construction. Furthermore, composites may be obtained by the incorporation of residue, solving problems of waste disposal. In the procedures undertaken, the industrial waste of thermoset polyurethane is transformed into a recycled aggregate, achieved by the cutting, grinding, characterization and classification in compliance to the ABNT standards (NBR 10.004 to10.007). Afterwards, with the use of a thermal press, it was possible to produce the slabs and characterize them according to the following properties: mechanical (tensile strength, and puncture), physical (water absorption, swelling and stiffness), thermal (conductivity) and the potential durability (resistance to impact, abrasion, chemical attack. ultraviolet and weather exposure, electrical resistance, and flammability). The test results indicated that the composite behaves similarly to materials used in civil construction, which enables its use in the area.
94

Extração, determinação da composição fenólica e avaliação do potencial de desativação de espécies reativas de oxigênio e da atividade anti-inflamatória de resíduos de amendoim, pimenta-rosa e pimenta-do-reino / Extraction, determine the phenolic composition and assessment of the potential deactivation of reactive oxygen species and anti-inflammatory activity of residue peanut skin, pink pepper and black pepper

Bergamaschi, Keityane Boone 19 April 2016 (has links)
O setor agroindustrial tem se expandido muito nos últimos anos, levando o país a um aumento na geração de resíduos agroindustriais, sendo que a maior parte deles ainda é descartada no meio ambiente, sem tratamento adequado, ou utilizada na alimentação animal, destinos que a priori, não geram ganhos econômicos para a agroindústria além de representarem gargalos logísticos e ambientais na sua disposição. Nesse sentido, o presente trabalho teve como objetivos otimizar o processo de extração de compostos bioativos, avaliar in vitro as atividades antioxidante, por meio da desativação de espécies reativas de oxigênio, e anti-inflamatória, bem como determinar a composição fenólica dos resíduos agroindustriais a saber: película de amendoim (Arachis hypogaea) (cultivares IAC886 e IAC505), pimenta-rosa (Schinus terebinthifolius Raddi) e pimenta-do-reino (Piper Nigrum L). O processo de otimização da extração de compostos antioxidantes foi realizado utilizando dois processos de extração, extração convencional e subcrítica, em delineamento composto central rotacional, utilizando como variáveis a temperatura e tempo e a pressão e temperatura, respectivamente, com os solventes etanol 80%, água e propilenoglicol 80%. Durante o processo de otimização a atividade antioxidante foi avaliada pelo método de sequestro do radical ABTS. Os melhores resultados foram obtidos para a extração convencional com os solventes etanol 80%, água e propilenoglicol 80%. A película de amendoim (IAC505) apresentou as maiores atividades antioxidantes (1.396,67, 580,44 e 859,89 μmol.g-1 em equivalentes de trolox, para os solventes etanol 80%, água e propilenoglicol 80%, respectivamente). A partir dos resultados obtidos para os solventes testados, utilizando a extração convencional, foram feitas outras análises de atividade antioxidante considerando o tempo e temperatura ideal de extração. Foram realizadas análises de avaliação da capacidade de redução de Folin-Ciocalteau e potencial de desativação dos radicais livres sintéticos (DPPH e ABTS) e espécies reativas de oxigênio (radicais peroxila, superóxido e ácido hipocloroso). O solvente de extração que apresentou melhores resultados em todos os ensaios foi o etanol 80%, sendo, portanto o solvente utilizado nas análises subsequentes. A partir da definição do melhor sistema extrator foram realizadas análises da composição fenólica, por meio das técnicas de cromatografia líquida de alta eficiência em modo analítico (HPLC-RP), cromatografia gasosa acoplada com espectrometria de massas (GC-MS), e avaliação in vitro da atividade anti-inflamatória. Foram identificados nos resíduos estudados procianidinas B1 e B2, ácido p-cumárico, miricetina, ácido ferúlico, ácido siríngico, ácido sinápico, epicatequina e catequina. A pimenta-do-reino diminui significativamente os níveis de TNF-α e nitritos, reduzindo assim o processo inflamatório gerado. Os resultados obtidos neste trabalho demonstram que estes resíduos agroindústrias possuem grande potencial biológico, podendo assim ser melhores aproveitados tanto pela indústria de alimentos quanto pela indústria farmacêutica. / The agribusiness sector has expanded greatly in recent years, leading the country to an increase in the generation of agro-industrial residues, even though most of them are still discarded in the environment without proper treatment, or used in animal feed, destinations that a priori do not generate economic gains for agribusiness besides representing logistical and environmental bottlenecks at your disposal. In this sense, the present study aimed to optimize the bioactive compounds extraction process, to evaluate in vitro the antioxidant activities, through the deactivation of reactive oxygen species, and anti-inflammatory as well as determine the phenolic composition of agro-industrial residues namely peanut skin (Arachis hypogaea) (IAC886 and IAC505 cultivars), pink pepper (Schinus terebinthifolius Raddi) and black pepper (Piper nigrum L). The optimization process of extraction of antioxidants was performed using two extraction processes, conventional extraction and subcritical on central composite design, using as variable temperature and time and the pressure and temperature, respectively, with solvents ethanol 80%, water and propyleneglycol 80%. During the optimization process the antioxidant activity was evaluated for the kidnapping method of ABTS radical. The best results were obtained for the conventional extraction with solvents ethanol 80%, water and propyleneglycol 80%. Peanut skin (IAC505) showed the highest antioxidant activity (1,396.67, 580.44 and 859.89 μmol.g-1 in Trolox equivalents, for solvents ethanol 80%, water and propyleneglycol 80%, respectively). From the results obtained for the solvents tested, using conventional extraction, other analyzes were done considering the antioxidant activity optimum time and temperature of extraction. Valuation analyzes were carried out of the Folin-Ciocalteau reduction capability and potential disabling of synthetic free radical (DPPH and ABTS) and reactive oxygen species (peroxyl radicals, superoxide and hypochlorous acid). The extraction solvent that showed better results in all tests was ethanol 80%, and therefore the solvent used in subsequent analyzes. From the definition of the best extraction system analyzes were made of phenolic composition by means of liquid chromatography techniques of high efficiency in analytic way (HPLC-RP), gas chromatography coupled with mass spectrometry (GC-MS), and reviewed in vitro anti-inflammatory activity. They were identified at residues studied procyanidins B1 and B2, p-coumaric acid, myricetin, ferulic acid, syringic acid, sinapic acid, epicatechin, and catechin. The black pepper significantly reduces TNF-α and nitrite levels, thereby reducing the inflammatory process generated. The results of this study demonstrate that these agribusinesses waste have great biological potential, and thus can be best availed by both the food industry and the pharmaceutical industry.
95

Desenvolvimento de modelo de avaliação, qualificação e melhoria contínua de empresas prestadoras de serviços ambientais pararesíduos industriais

Santos, Marise Keller dos January 2018 (has links)
A Política Nacional de Resíduos sólidos exige de uma Empresa Produtora de Resíduos (EPR) o estabelecimento de uma relação de responsabilidade compartilhada com os seus Prestadores de Serviços Ambientais (PSAs) seja para a destinação ambientalmente adequada como para o estabelecimento de mecanismos de logística reversa de resíduos e produtos com ciclo de vida finalizado. Estas duas exigências fortalecem recomendações existentes em diferentes Sistemas de Gestão certificados, como por exemplo, NBR ISO 9001, NBR ISO 14001, OHSAS 18001, dentre outros, para a avaliação de fornecedores. Este trabalho objetivou o desenvolvimento de um modelo de avaliação da gestão de PSAs para resíduos industriais. Esse desenvolvimento teve origem a partir da demanda de um conjunto de empresas de um segmento industrial no Rio Grande do Sul. O modelo desenvolvido é composto por quatro macrofases, as quais são divididas em 12 passos e 31 atividades. Na primeira macrofase, construção da matriz de desempenho, foram identificadas qualidades demandadas e indicadores relevantes para a avaliação de fornecedores. Foi aplicada uma ferramenta multicritério, Desdobramento da Função Qualidade (QFD) para o tratamento das demandas e indicadores das nove áreas de gerenciamento de um PSA, quais sejam: aspectos legais; qualidade; resíduos; aguas, efluentes, emissões e ruídos; saúde e segurança; riscos; tecnologia; rotinas empresariais e, inovação e tecnologia. Na segunda macrofase, avaliação global dos PSAs, foi construído o instrumento para avaliação, bem como um manual que reune todos os procedimentos para a condução da avaliação, o qual também é empregado como instrumento de apoio para as atividades de capacitação de avaliadores. Na macrofase trêsforam estabelecidos e aplicados dois critérios mínimos para a avaliação dos resultados de desempenho dos indicadores gerenciais dos PSAs. As informações geradas são sistematizadas em relatórios padronizados para EPRs e PSAs. Na quarta e última macrofase com base em um ranqueamento do desempenho dos indicadores foi possível identificar os pontos críticos para o desenvolvimento dos PSAs avaliados. Enquanto resultados, o modelo permite: (i) a identificação de PSAs considerados estratégicos; (ii) a avaliação individual do desempenho de cada PSA; (iii) a avaliação comparativa de desempenho entre PSAs, que oferecem um mesmo serviço ambiental; (iv) a identificação de indicadores de baixo desempenho dos PSAs; e (v) a elaboração de um plano de ação para melhoria contínua desses PSAs. As conclusões são apresentadas em dois contextos, o primeiro apresenta as mesmas relacionadas ao desenvolvimento do modelo considerando sua aplicação para empresas de um mesmo setor em uma mesma localização geográfica. O segundo contexto apresenta as conclusões relacionadas a aplicação deste modelo, onde foi possível constatar que o modelo auxiliou no processo de organização /atuação em conjunto do setor metal mecânico clarificando as necessidades de melhorias demandadas por um grupo e não somente por uma EPR, junto aos seus PSAs. / The National Solid Waste Policy requires from the Waste Generator Companies (WGCs) to establish a shared responsibility relationship with its Environmental Service Providers (ESPs) either for the environmental appropriate destination or for the establishment of waste and end-of-life products reverse logistic mechanisms.These two requirements strengthen recommendations in different certified Management Systems, such as NBR ISO 9001, NBR ISO 14001, OHSAS 18001, among others, to supplier evaluation.This work aimed the development of an evaluation model for the industrial waste management PSAs. This development was originated from an industrial segment group demand in Rio Grande do Sul. The model developed is composed by four macrophases, which are divided into 12 steps and 31 activities. In the first macrophase, which was the construction of the performance matrix, qualities demanded and relevant indicators for the evaluation of suppliers were identified. A multi-criteria tool, Quality Function Deployment (QFD), was applied to deal with the demands and indicators of the nine management areas of a ESP, namely: legal aspects; quality; solid waste; water, effluents, emissions and noise; health and safety; risks; technology; business routines; and innovation and technology. In the second macrophase, named the ESPs global assessment, the evaluation instrument was constructed, as well as a manual that combines all the procedures for conducting the evaluation, which is also used as a support tool for the training activities of evaluators.In macrophase three were established and applied two minimum criteria for the performance results evaluation of the ESPs management indicators. The information generated is systematized in standard reports for WGCs and ESPs. In the fourth and last macrophase, based on indicators performance ranking, was possible to identify the critical points for the ESPs evaluated development. As results, the model allows: (i) the strategic ESPs identification; (ii) the individual ESP performance evaluation; (iii) comparative performance evaluation among ESPs, which offer the same environmental service; (iv) the identification of ESPs weakness performance indicators; and (v) the action plan construction for ESPs continuous improvement. The conclusions are presented in two contexts. The first presents the conclusions related to the model development considering its application to companies with the same sector in the same location. The second context presents the conclusions related to the application of this model, where it was possible to verify that the model assisted in the process of organization / performance in the metal mechanic sector, enlightening what are the demanded improvements by a group and not only by a WGC along with their ESPs.
96

Prevenção à poluição industrial: identificação de oportunidades, análise dos benefícios e barreiras / Industrial pollution prevention: opportunities assessment, benefits and barriers analysis

Santos, Carmenlucia 02 September 2005 (has links)
A prevenção à poluição é uma abordagem de gerenciamento ambiental que prioriza a redução dos resíduos na fonte como forma de preservar os recursos naturais e reduzir o desperdício de materiais, água e energia, em contraposição à abordagem tradicional, que se apóia nas tecnologias de controle e tratamento de resíduos. Apesar de resultar em benefícios ambientais e econômicos, existem uma série de barreiras que impedem uma maior disseminação das práticas de prevenção à poluição nas indústrias, dentre as quais a principal é a falta de conscientização em relação aos benefícios. Para eliminar esta barreira, faz-se necessário o desenvolvimento e a divulgação dos conceitos e ferramentas de apoio ao processo de identificação de oportunidades, ferramentas para o monitoramento e avaliação da performance ambiental dos processos produtivos, bem como de estudos de caso propondo alternativas de prevenção à poluição para os diferentes setores industriais. Esta pesquisa tem como objetivo fundamental apresentar os conceitos, sistemáticas e ferramentas necessárias ao entendimento da abordagem de prevenção à poluição, e ao desenvolvimento, implantação e monitoramento de programas de prevenção à poluição em processos industriais. Como forma de avaliar a aplicação do conceito e das ferramentas de identificação de oportunidades, e os benefícios e barreiras, foi realizada a avaliação de um processo produtivo industrial. Os resultados obtidos fornecem embasamento teórico para que outros trabalhos semelhantes sejam desenvolvidos, e servem como incentivo para que a empresa na qual foi realizada a avaliação, passe a adotar o conceito de prevenção à poluição como princípio norteador nas suas atividades de gestão ambiental. / Pollution prevention is an environmental management approach that prioritizes the source reduction of wastes as a way to preserve natural resources and reduce material, water and energy losses, conversely to the traditional approach, based on end of pipe technologies. In spite of the environmental and economic benefits, many barriers can impede the widespreading of pollution prevention practices at industry, among them, the most important one is the lack of consciousness on the pollution prevention benefits. To overcome this barrier, it is necessary to develop and report concepts and tools to support the opportunity assessment process, tools to monitor and evaluate industrial processes environmental performance, as well as case studies on pollution prevention alternatives to different industrial sectors. This research fundamental aim is to present the concepts, approaches and tools necessary to understand the pollution prevention approach and to develop, implement and monitor industrial pollution prevention plans. A case study was conducted in a company to evaluate the concept application, the utilization of the apportunities assessment tools, and the benefits and barriers. The results provide a theoric framework so that other similar studies can be conducted, and also serve as an incentive for the company where the case study was conducted, to improve its environmental management activities by adopting pollution prevention concept as a guiding principle.
97

Destinação de resíduos industriais e pós-consumo: a contribuição das centrais de triagem cooperativadas

Almeida, Francieli Aparecida de 27 February 2014 (has links)
Submitted by Mariana Dornelles Vargas (marianadv) on 2015-05-26T14:22:27Z No. of bitstreams: 1 destinacao_residuos.pdf: 582222 bytes, checksum: f9d4c4f365db39467e9c520303ef0e64 (MD5) / Made available in DSpace on 2015-05-26T14:22:27Z (GMT). No. of bitstreams: 1 destinacao_residuos.pdf: 582222 bytes, checksum: f9d4c4f365db39467e9c520303ef0e64 (MD5) Previous issue date: 2014-02-27 / UNISINOS - Universidade do Vale do Rio dos Sinos / A discussão sobre redução dos resíduos e sustentabilidade tem se mostrado prioritária desde que se percebeu a geração excessiva de novos produtos no mercado e a falta de gerenciamento dos resíduos, principalmente os resíduos sólidos urbanos - RSU. Tais resíduos são provenientes do consumo das famílias e da atividade industrial. Com tal excesso, indústrias têm passado a trabalhar de forma a oferecer alternativas para mudar esse cenário. O objetivo dessa pesquisaé verificar como as centrais de triagem cooperativadas têm contribuído com a reciclagem de resíduos sólidos gerados pelas indústrias. Para realização dessa pesquisa foram utilizados os métodos de revisão bibliográfica e observação não participante. A coleta de dados foi realizada por meio de entrevistas com questionários norteadores e relatórios. Os resultados evidenciaram que as indústrias pesquisadas têm seus processos direcionados em atendimento à redução dos resíduos, ou, ao correto encaminhamento do mesmo, seja para recolhimento da prefeitura (coleta seletiva) ou aterro sanitário controlado. Por outro lado, as centrais de triagem cooperativadas buscam fortalecer seu elo na cadeia logística reversa, processando e reciclando os materiais, formando um ciclo fechado de produção, e pelo que se pode observar necessitam do apoio dos demais atores envolvidos nesse processo, o governo, as empresas privadas e a sociedade em geral para um pleno funcionamento. / The discussion about waste reduction and sustainability has proven a priority since perceived the excessive generation of new products to market and the lack of waste management, mainly municipal solid waste – MSW- provide by household consumption. So, with such excess, the industries are working in order to offer alternatives to change this scenario. The objective of this research is to see how the central cooperative sorting have contributed to the recycling of solid waste generated by industries. For this survey the methods of literature review and participant observation were used. Data collection was conducted through interviews with guiding questionnaires and reports by cooperatives. The results showed that the industries surveyed have directed their processes to reduce waste, or the correct disposal of it, to direct for prefecture (selective collection) or controlled landfill. On the other hand, the recycling cooperatives have seek strengthen its link in the reverse logistics chain, processing and recycling materials , forming a closed production cycle , and need the support of other actors involved in this process, the government, private companies and society in general to a fully functioning .
98

Estudo da aplicação de ferro zero no tratamento de efluente têxtil / Evaluation of zero-valent iron in textile effluent treatment

Pereira, Wellington da Silva 19 November 2004 (has links)
O presente trabalho de mestrado descreve o estudo da viabilidade da aplicação de ferro de valência zero no tratamento de quatro classes de corantes muito utilizados pela indústria têxtil: corante preto remazol B (azo), vermelho remazol RB 133 (triazina), azul remazol brilhante RN (antraquinona) e turquesa remazol G 133 (ftalocianina). O processo também foi aplicado na remediação de um efluente têxtil. O Fe0 mostrou uma grande eficiência na degradação dos corantes estudados, empregando-se uma concentração de Fe0 de 5 g L-1 (oriundo de um resíduo de processo metalúrgico) no tratamento de soluções de azocorantes com concentração de 100 mg L-1, obteve-se uma taxa de descoloração superior a 90% em apenas 15 minutos de tratamento. Uma característica bastante favorável do processo proposto foi sua ampla faixa operacional de pH, observando-se uma degradação do grupo cromóforo superior a 80% para soluções com pH entre 1,5 e 9 (sendo a faixa ótima observada entre 3 e 5). O processo também se mostrou pouco susceptível a variações na concentração de corante (faixa estudada: 25 - 150 mg L-1). Por outro lado, a eficiência do tratamento com ferro de valência zero mostrou-se dependente do tamanho de partícula, da massa e da superfície do material metálico. O mecanismo de degradação também variou em função do emprego de condições anaeróbias ou aeróbias. Para 15 minutos de tratamento, a descoloração dos corantes e do efluente têxtil atingiu níveis ao redor de 95% independente da condição anaeróbia/aeróbia. Entretanto na presença de O2 , observou-se uma redução do carbono orgânico total de até 75% (contra cerca de 25% na condição anaeróbia), mostrando que quando esta espécie aceptora de elétrons esta presente, o mecanismo envolve etapas de oxidação, provavelmente associadas a reações do tipo Fenton. O processo de tratamento emp~egando Fe0 apresentou uma cinética de pseudo-primeira ordem para a degradação dos grupos cromóforos e para a mineralização da matéria orgânica dos corantes e do efluente real. Para os corantes, as constantes cinéticas apresentaram a seguinte ordem: ftalocianina < azo < antraquinona < triazina. De um modo geral, o processo remediatiyo estudado apresentou boas características, que o capacitam como uma alternativa promissora para o tratamento de corantes e efluentes têxteis. / This work describes a study to evaluate the viability of zero-valent iron in the treatment of four classes of dyes that are commonly used in the textile industry: Remazol Black B (azo), Remazol Red RB133 (triazine), Remazol Brilliant Blue RN (anthraquinone) and Remazol Turquoise G133 (phtalocyanine). The process was also apllied in the textile effluent remediation. Fe0 process showed a great efficiency in the degradation of the studied dyes, it was obtained a discoloration level higher than 90% in just 15 minutes of treatment employing 5 g L-1 of Fe0 (obtained from of a metallurgic residue) in the degradation of 100 mg L-1 azodye solutions. A quite favorable characteristic of the proposed process was the wide pH operational range; the degradation of chromophore group was upper to 80% for azodye solutions with pH between 1,5 and 9 (the optimum range observed between 3 and 5). The process showed low susceptibility to variations in dye concentration (studied range: 25 - 150 mg L-1). On the other hand, the efficiency of the treatment with zero-iron valence zero was dependent on particle size, mass and surface of the metallic material. The degradation mechanism also varied as function of anaerobic and aerobic conditions. For 15 minutes of treatment, the discoloration of studied dyes and textile effluent reached levels around 95% independent of anaerobic/aerobic condition. However, in the presence of O2, the total arganic carbon showed a reduction up to 75% (versus just around 25% observed in the anaerobic condition). These results showed that when this electron acceptor species is present, the mechanism involves oxidation stages, probably associated with type Fenton reactions. The treatment using Feo presented pseudo-first arder kinetics for the degradation of chromophore groups and for organic matter mineralization. The kinetic constants presented the following order for the studied dyes: phtalocyanine < azo < anthraquinone < triazine. In general, the studied remediative process showed some good characteristics, which makes it a promising alternative for the treatment of dyes and textile effluents.
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Empresas que aprendem e inovam: estudo de caso da valoração de resíduo agroindustrial proveniente da soja na Coplacana com foco em frações proteicas por meio de método analítico verde / Companies that learn and innovate: a case study of the evaluation of agroindustrial residue from soybean in Coplacana focusing on protein fractions by means of a green analytical method

Rossi, Renata Cristina 17 June 2019 (has links)
A presente pesquisa objetivou o desenvolvimento de um estudo de caso voltado à valoração de resíduo agroindustrial de soja gerado na Coplacana (Unidade de Grãos, Piracicaba, SP, Brasil), com o intuito de se determinar o potencial deste material como um recurso com vistas às frações proteicas através de método analítico verde. O Brasil é um dos principais países produtores de alimentos, contudo, ainda enfrenta a realidade do desperdício em todas as etapas desta cadeia produtiva. A geração de resíduos está associada ao desperdício no uso de insumos, às perdas entre a produção e o consumo, e aos materiais gerados ao longo da cadeia agroindustrial. Para que as indústrias consigam alcançar seu desempenho ambiental, também estarem de acordo com as exigências legais e mercadológicas é preciso gerenciamento dos resíduos sólidos gerados na cadeia produtiva associada a novos modelos de gestão empresarial. Neste sentido, o reaproveitamento de resíduos agroindustriais no país apresenta-se como uma porta de entrada para novos modelos de negócios, e tem demandado uma reconfiguração de todos os processos, produtos e serviços verdes e sustentáveis para além dos muros de uma empresa, rumo à bioeconomia circular. Procedeu-se o desenvolvimento da pesquisa através da revisão de literatura pertinente, apresentação geral da empresa, entrevista junto aos gestores, estudo de caso e apresentação dos resultados. No que tange ao levantamento da quantidade de material residual da cadeia de soja gerado na Coplacana, concluiu-se com base nos resultados encontrados que, um novo modelo de negócios (lançamento do Food Tech Hub) e métodos (com base na tecnologia de micro-ondas para digestão, extração e transformação de resíduos agroindustriais em escalas de laboratório e industriais) se colocam como uma alternativa viável, robusta e aderente aos novos pressupostos da empresa. / The present research aimed at the development of a case study focused on the evaluation of soybean agro-industrial residue generated at Coplacana (Grain Unit, Piracicaba, SP, Brazil), whose main objective was to determine the potential of this material as a resource with views to the protein fractions by green analytical method. Brazil is one of the main food producing countries, however, it still faces the reality of waste in all stages of this production chain. The generation of waste is associated with the waste in the use of inputs, the losses between production and consumption, and the materials generated along the agro-industrial chain. In order for industries to achieve their environmental performance, they are also in accordance with legal and marketing requirements. It is necessary to manage solid waste generated in the production chain associated with new business models. In this sense, the reuse of agro-industrial waste in the country presents itself as a gateway to new market models, and has demanded a reconfiguration of all green and sustainable processes, products and services beyond the walls of a company, towards the circular bio-economy. The research was developed through a review of relevant literature, general presentation of the company, interview with managers, case study and presentation of results. Regarding the survey of the amount of residual material from the soybean chain generated at Coplacana, it was concluded based on the results found that a new business model (Food Tech Hub launch) and methods (based on micro- waves for digestion, extraction and transformation of agroindustrial waste in laboratory and industrial scales) are considered as a viable alternative, robust and adherent to the new assumptions of the company.
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Studies On The Combustion And Gasification Of Concentrated Distillery Effluent

Patel, Nikhil 10 1900 (has links)
The need for effective disposal of huge volumes of industrial waste is becoming more challenging due to expected imposition of stringent pollution control regulations in the near future. Thermochemical conversion, particularly gasification of organics in the waste is considered the best route from the perspective of volume reduction and prevalent eco-friendly concept of waste-to-energy transformation. It is considered imperative to have adequate understanding of basic combustion features as a part of the thermochemical conversion process, leading to gasification. The aim of this thesis is to understand the fundamental combustion processes associated with one of the top listed hazardous wastes from distilleries (Biochemical Oxygen Demand (BOD) ~ 40,000 - 50,000 mg/L), commonly known as vinasse, stillage or spent wash, through experiments and modeling efforts. Specially designed experiments on distillery effluent combustion and gasification are conducted in laboratory scale reactors. As an essential starting point of the studies on ignition and combustion of distillery effluent containing solids consisting of 62 ± 2 % organics and 38 ± 2 % inorganics (primarily sugarcane derivatives), the roles of solids concentration, drop size and ambient temperature were investigated through experiments on (1) liquid droplets of 65 % and 77 % solids (remaining water) and (2) spheres of dried effluent (100 % solids) of size 0.5 mm to 20 mm diameter combusted at ambient temperatures of 773 to 1273 K. The investigation reveals that the droplets burn with two distinct regimes of combustion, flaming and char glowing. The ignition delay ‘t1’ of the droplets increased with size as is in the case of non-volatile droplets, while that of bone-dry spheres was found to be independent of size. The ‘t1’ decreased with increase in solids concentration. The ignition delay has showed an Arrhenius dependence on temperature. The initial ignition of the droplets and the dry spheres led to either homogeneous (flaming) or heterogeneous (flameless) combustion, depending on the ambient temperature in the case of sphere and on solid concentration and the ambient temperature, in the case of liquid droplets. The weight loss during the flaming combustion was found to be 50 - 80 % while during the char glowing it was 10-20 % depending on the ambient temperature. The flaming time tc is observed as tc~ d2c , as in the case of liquid fuel droplets and wood spheres. The char glowing time tc' is observed as tc ~ d2c as in the case of wood char, though the inert content of effluent char is as large as 50 % compared to 2 - 3 % in wood char. In the case of initial flameless combustion, the char combustion rate is observed to be lower. The heterogeneous char combustion in quiescent air in controlled temperature conditions has been studied and modeled using one-dimensional, spherico-symmetric conservation equations and the model predicts most of the features of char combustion satisfactorily. The measured surface and core temperatures during char glowing typically are in the range of 200 to 400 K and are higher than the controlled temperature of the furnace. Based on the results of single droplet combustion studies, combustion experiments were conducted in a laboratory scale vertical reactor (throughput ranging from 4 to 10 g/s) with the primary aim of obtaining sustained combustion. Spray of effluents with 50 % and 60 % solids (calorific value 6.8 - 8.2 MJ/kg), achieved by an air blast atomizer, was injected into a hot oxidizing environment to determine the parameters (ambient temperature and air-fuel ratio) at which auto-ignition could occur and subsequently studies were continued to investigate pre-ignition, ignition and combustion processes. Effluent with lower solids concentration was considered first from the point of view of the less expensive evaporator required in the field conditions for concentration and a spin-off in terms of better atomization consequently. Three classes of experiments were conducted: 1) Effluent injection from the wall with no auxiliary heat input, 2) Effluent injection with auxiliary heat input and 3) effluent injection within kerosene enveloping flame. Though individual particles in the spray periphery were found to combust, sustained spray combustion was not achieved in any of the three sets of experiments even with fine atomization. While conducting the third class of experiments in an inclined metallic reactor, sustained combustion of the pool resulting of accumulated spray seemed to result in large conversion of carbon. This led to the adoption of a new concept for effluent combustion in which the residence time is controlled by varying reactor inclination and the regenerative heat transfer from the product gases supplies heat for endothermic pre-ignition process occurring on the bed. Combustion and gasification experiments were conducted in an inclined plate reactor with rectangular cross section (80 mm x 160 mm) and 3000 mm long. A support flame was found necessary in the injection zone in addition to the regenerative heat transfer. Effluent with 60% solids was injected as film on the reactor bed. This film disintegrated into fine particles due to induced aerodynamic stretching and shear stripping. Combustion of individual particles provided exothermic heat profile and resulted into high carbon conversion. However, effluent clogging in the cold injection zone hindered system from attaining steady state. Effluent injected directly on the hot zone caused it to remain mobile due to the spheroidal evaporation and thus assuaging this problem. Improved mass distribution was achieved by displacing nozzle laterally in a cycle, actuated by a mechanism. Consistent injection led to sustained effluent combustion with resulting carbon conversion in excess of 98 %. The typical gas fractions obtained during gasification condition (air ratio = 0.3) were CO2 = 14.0 %, CO = 7.0 %, H2 = 12.9 %, CH4 - 1 % H2S = 0.6 - 0.8 % and about 2 % of saturated moisture. This composition varied due to variation in temperature (± 30 K) and is attributed to combined effect of local flow variations, shifting zones of endothermic processes due to flowing of evaporating effluent over a large area. In order to minimize this problem, experiments were conducted by injecting effluent at higher solids (73 % solids is found injectable). The effluent was found to combust close to the injection location-due to the reduced ignition delay and lower endothermic evaporation load helped raising the local temperature. This caused the pyrolysis to occur in this hottest zone of the reactor with higher heating rates resulting in larger yield of devolatilized products and improved char conversion. Effluent combustion was found to sustain temperature in the reactor under sub-stoichiometric conditions without support of auxiliary heat input and achieved high carbon conversion. These results inspired the use of higher concentration effluent, which is also known in the case of wood to have improved gasification efficiency due to reduction in moisture fraction. In addition, the recent studies on the sulfur emission in the case of black liquor combustion in recovery boilers have revealed that with increase in solids concentration, release of sulfur in gas phase is reduces. The required concentration can be carried out using low-grade waste heat from the reactor itself. It was found through experiments that, even though spray ignition occurred at this concentration, the confined reactor space prevented the spray from attaining sustained combustion. This led to the conduct of experiments in a new vertical reactor with adequate thermal inertia, essential to prevent variations in local temperature to reach a steady state gasification and required space to accommodate the spray. The results of the experiments conducted in the vertical reactor in which effluents with 73 % solids, heated close to the boiling point and injected as fine spray in a top-down firing mode are consolidated and reported in the thesis in detail. Single particle combustion with enveloping faint flame was seen unlike stable flame found in coal water slurry spray combustion. Sustained gasification of gas-entrained particles occurred at reactor temperature in the range of 950 K - 1000 K and sub-stoichiometric air ratio 03 - 0.35 without the support of auxiliary fuel. The typical gas fractions obtained during gasification condition (air ratio = 0.3) were CO2 = 10.0 -11.5 %, CO - 10.0 - 12.0 %, H2 - 6.7 - 8.0 %, CH4 = 1.75 % H2S = 0.2 - 0.4 % and about 2 % of saturated moisture. The carbon conversion obtained was in the range of 95 - 96 %. These experiments have provided the conditions for gasification. The extraction of potassium salts (mostly sulfates, carbonate and chloride) from the ash, using a simple water leaching process, was found to recover these chemicals to as high an extent as 70 - 75 % of total ash. In summary it is concluded that increasing the solid concentrations to as high levels as acceptable to the system (~ 75 %) and introducing as a fine spray of heated material (~ 363 K) into furnace with air at sub-stoichiometric conditions in a counter current combustion reactor will provide the frame work for the design of a gasification system for vinasse and similar effluent material. The thesis consists of seven chapters. Chapter 1 introduces the problem and motivation of the work presented in the thesis. Literature review is presented in Chapter 2. The Chapter 3 deals with the single particle combustion studies. The results of effluent spray combustion experiments conducted in a laboratory scale vertical reactor are presented in Chapter 4. The results of combustion and gasification experiments conducted in another variant of a reactor, namely, inclined flat plate rectangular reactor is consolidated in Chapter 5. The results of gas-entrained spray gasification experiment of higher concentration effluent injected as spray in the vertical reactor are presented in Chapter 6. The general conclusions and scope for the future work are presented in the concluding chapter 7.

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