Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains viii, 75 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 71-73).

Master of Engineering / Global warming and diminishing energy supplies are two major current concerns. Disposal of plastic wastes is also a major concern. The aim of this research is to address these three concerns by developing a solar powered process, using waste plastics as fuel to generate energy. Research into: i) solar concentrators for high temperature thermochemical processes, and ii) pyrolysis/gasification of waste plastics has been separately reported in the literature. In this study the aim was to bring these fields of research together to design a solar receiver-reactor suitable for the production of a synthesis gas, consisting of hydrogen, from waste plastics. To achieve this aim, studies of plastic decomposition behaviour using the thermal analysis method known as thermogravimetric analysis were conducted. Solar concentrators and their potential to be used for thermochemical processes were also studied. Firstly, the thermal decomposition behaviour of common plastics, namely low density polyethylene (LDPE), high density polyethylene (HDPE), polyethylene terephthalate (PET) and polyvinyl chloride (PET), were studied using thermogravimetry at heating rates of 5, 10, 20, 50 and 100 ºC/min. The kinetic parameters for the decomposition were determined from these experiments. Secondly, a simple solar receiver-reactor in which the plastic decomposition could be achieved was designed. The solar receiver-reactor designed was a quartz tube reactor which can be placed in the focus of a dish type parabolic concentrator capable of generating up to 3 kW in the focus of diameter 50 mm. The thermogravimetric analysis of plastic samples showed that LDPE, HDPE and PET have a single-step decomposition, whereas PVC has a two-step decomposition. The first step was related to the release of hydrogen chloride from the PVC and the second step was related to the release of hydrocarbon from the polymer backbone. If PVC is pretreated to release HCl it can be mixed with other plastics for a single step decomposition. It is likely that a single step plastic decomposition can be achieved in a directly irradiated solar receiver-reactor to generate useful gases consisting of hydrogen.

Master of Engineering / Global warming and diminishing energy supplies are two major current concerns. Disposal of plastic wastes is also a major concern. The aim of this research is to address these three concerns by developing a solar powered process, using waste plastics as fuel to generate energy. Research into: i) solar concentrators for high temperature thermochemical processes, and ii) pyrolysis/gasification of waste plastics has been separately reported in the literature. In this study the aim was to bring these fields of research together to design a solar receiver-reactor suitable for the production of a synthesis gas, consisting of hydrogen, from waste plastics. To achieve this aim, studies of plastic decomposition behaviour using the thermal analysis method known as thermogravimetric analysis were conducted. Solar concentrators and their potential to be used for thermochemical processes were also studied. Firstly, the thermal decomposition behaviour of common plastics, namely low density polyethylene (LDPE), high density polyethylene (HDPE), polyethylene terephthalate (PET) and polyvinyl chloride (PET), were studied using thermogravimetry at heating rates of 5, 10, 20, 50 and 100 ºC/min. The kinetic parameters for the decomposition were determined from these experiments. Secondly, a simple solar receiver-reactor in which the plastic decomposition could be achieved was designed. The solar receiver-reactor designed was a quartz tube reactor which can be placed in the focus of a dish type parabolic concentrator capable of generating up to 3 kW in the focus of diameter 50 mm. The thermogravimetric analysis of plastic samples showed that LDPE, HDPE and PET have a single-step decomposition, whereas PVC has a two-step decomposition. The first step was related to the release of hydrogen chloride from the PVC and the second step was related to the release of hydrocarbon from the polymer backbone. If PVC is pretreated to release HCl it can be mixed with other plastics for a single step decomposition. It is likely that a single step plastic decomposition can be achieved in a directly irradiated solar receiver-reactor to generate useful gases consisting of hydrogen.

Made available in DSpace on 2015-03-26T13:51:59Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1426624 bytes, checksum: 8ec26861eeae9b5c7bd7e331f352548c (MD5) Previous issue date: 2009-07-24 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The oil extraction from Jatropha curcas seeds as raw material to biodiesel production releases a large quantity of solid residue, called cake.This Jatropha cake is formed by lignocellulolytic residues, water, minerals salts, but also contains toxic compounds and antinutritional factors. The correct destination of this residue is of great interesting to biofuel industries. The use of these residues as a substrate to grow the white rot fungi, Pleurotus ostreatus, may be a low cost alternative to produce the economic and industrial interesting products such as enzymes, proteins and edible mushrooms. Moreover, this fungus produces enzyme capable of degrade different toxic compounds and antinutritional factors. ln this study Jatropha cake, pure or in mixture with agro-industrial residues, was used as substrate to grow P. ostreatus objecting to produce mushrooms, eliminate phorbol ester, antinutritional factors and also, to evaluate the reduce lignin, cellulose and hemicellulose. After 45 days of P. ostreatus mycelia inoculation in the substrate, it was observed high production of fungus biomass, and degradation of 50 % of lignin and 20 % of cellulose and hemicellulose. The substrates which present higher fungus biomass production and lignocellulolitic degradation were used to assess the ability of P. ostreatus to produce mushroom and to degrade phorbol ester, phytic acid and tannins. After 60 d of incubation, it was observed good production of mushroom, reduction of lignocellulolytic compounds and loss of dry mass, reduction of phytic acid in 95 % and 85 % of tannins (equivalent a tannin acid) and 99 % of phorbol ester. These mushrooms and the substrates after 60 d of colonization by P. ostreatus had concentrations of phorbol esters smaller than that found in provenances of non toxic J. curcas from México. Therefore, P. ostreatus has the ability of degrade toxic compounds, antinutritional factors and lignooellulosio compounds present in Jatropha cake. The alternative of using Jatropha cake as substrate to mushroom and enzymes production, add value to this residues, as well as detoxifying it show high potential to use Jatropha cake as animal food, beyond deoreasing the environmental damage. / A produção de biodiesel utilizando o óleo da semente de pinhão manso (Jatropha curcas) como matéria-prima libera grande quantidade de resíduos sólidos, denominado de torta.Essa torta apresenta composição diversificada, contendo não só compostos ligninocelulósicos, água e sais minerais, mas também compostos tóxicos e fatores antinutricionais. A destoxificação e o reaproveitamento dessa torta de pinhão manso são de grande interesse da indústria do biocombustível. A utilização desses resíduos como substrato para cultivo de fungos de podridão branca, Pleurotus ostreatus, pode ser uma alternativa de baixo custo e que permite a produção de produtos de interesse econômico e industrial como enzimas, proteínas e cogumelos comestíveis. Além disso, esse fungo produz enzimas capazes de degradar diferentes substâncias tóxicas, fatores antinutricionais e compostos ligninocelulósicos. Neste trabalho, a torta de pinhão manso pura, ou em mistura com outros resíduos agroindustriais, foi utilizada como substrato para crescimento micelial de P. ostreatus visando à eliminação de compostos tóxicos, fatores antinutricionais e a redução do teor de lignina, celulose e hemicelulose. Inicialmente, para verificar a viabilidade micelilal e a degradação compostos ligninocelulósicos presente na torta de pinhão manso. P. ostreatus PLO 6 foi inoculado em substratos à base da torta de pinhão manso, adicionado ou não de resíduos agroindustriais. Após 45 dias de incubação, verificou-se elevada produção de biomassa fúngica, 50 % de degradação de lignina e 20 % de consumo de celulose e hemicelulose. Os substratos que apresentaram maior produção de biomassa fúngica e também a maior degradação de compostos ligninocelulósicos foram utilizados para avaliar a capacidade de P. ostreatus formar cogumelos, além de degradar éster de forboI, ácido fítico e taninos. Após 60 dias de incubação, observou-se boa produção de cogumelos e degradação de compostos Iigninocelulósicos, com significativa perda da massa seca, redução de 95 % de ácido fítico, 85 % de taninos (equivalente a ácido tânico), 99 % de éster de forboI e aIta produtividade de cogumelos. Após o período de incubação, tantos os cogumelos de P. ostreatus como os substratos utilizados apresentaram concentrações de éster de forboI menor que o encontrado em variedade de J. curcas não tóxicas do México. Conclui-se que P. ostreatus tem capacidade de degradar composto tóxico, fatores antinutricionais e compostos Iigninocelulósicos presentes na torta de pinhão manso. O uso alternativo de torta de pinhão manso como substrato para cultivo de cogumelos e enzimas, destoxificando-o, agrega vaIor a esse resíduo, e apresenta um aIto potencial do uso dessa torta como alimento, além de diminuir os danos ambientais causados peIo descarte direto.