Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 145-148). Also available via the Internet.

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Thesis (Ph. D.)--University of Sydney, 2004. / Title from title screen (viewed 7 May 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Dept. of Chemical Engineering, Graduate School of Engineering. Includes bibliographical references. Also available in print form.

Made available in DSpace on 2015-04-22T22:08:46Z (GMT). No. of bitstreams: 1 Flavia Regina S dos Santos.pdf: 3668436 bytes, checksum: 5927f9f1725473e3fbb92116c1ea1fa2 (MD5) Previous issue date: 2013-03-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The search for new unconventional materials for construction based on renewable sources has contributed to environmental issues and sustainable development. In the current context of environmental and technological fibers in the Amazon region have become increasingly prominent, with respect to its use in products from various sectors of engineering. Among these, one can cite the example of curauá (Ananas erectifolius), species of bromeliad that is part of the pineapple family curauá has become a very attractive plant, both the economic point of view, because it has easy access and require low labor cost, as the scientific point of view, because it has low density and high strength. This paper presents a study of the viability of production and assessment of curauá (Ananas erectifolius) fiber panels, with and without wastes of Amazonian timber species amapá-doce (Brosimum parinarioides Duk) and louro-inhamuí (Ocotea cymbarum H.BK.), produced under pressure with bi-component polyurethane resin-based castor oil. The study was divided into three stages, the first characterizations were made physical, chemical and mechanical properties of the fiber, and the second time fabricated panels and the tests of bending, tensile and screw perpendicular surface according to standard NBR 14810-2. The results indicate that the panels showed good mechanical and physical properties, which is in accordance with the Brazilian standard. It is hoped that the study will enable the development and future generation of longer an option alternative material for the construction industry, so it is proved its good performance and can meet the technical requirements for the construction and furniture area. / A busca por novos materiais não convencionais para construção civil à base de fontes renováveis tem contribuído com questões ambientais e com o desenvolvimento sustentável. No atual contexto ambiental e tecnológico as fibras da região amazônica brasileira têm cada vez mais se destacado, com relação ao seu uso em produtos dos mais diversos setores da engenharia. Dentre estas, pode-se citar o exemplo do curauá (Ananás erectifolius), espécie de bromeliácea que faz parte da família do abacaxi. O curauá tem se tornado uma planta bem atrativa, tanto pelo ponto de vista econômico, por possuir fácil acesso e necessitar de mão de obra de baixo custo, quanto pelo ponto de vista científico, por possuir baixa densidade e elevada resistência mecânica. O presente trabalho apresenta um estudo da viabilidade de produção e avaliação de painéis de fibra de curauá (Ananás erectifolius), sem e com resíduos de madeiras Amazônicas das espécies amapá-doce (Brosimum parinarioides Duk) e louro-inhamuí (Ocotea cymbarum H.BK.), produzidos sob pressão com resina poliuretana bi-componente à base de óleo de mamona. A pesquisa foi dividida em três etapas, na primeira foram feitas as caracterizações físicas, químicas e mecânicas da fibra, e no segundo momento confeccionados os painéis e realizados os ensaios de flexão estática, tração perpendicular e arrancamento de parafuso de superfície de acordo com a norma NBR 14810-2. Os resultados obtidos apontam que os painéis apresentaram boas propriedades físico-mecânicos, estando de acordo com a norma brasileira. Espera-se que o estudo possibilite o desenvolvimento e a futura geração de mais uma opção de material alternativo para o setor da construção civil, sendo assim fica comprovado o seu bom desempenho, podendo atender os requisitos técnicos para a área moveleira e construção civil.

This thesis looks into issues related to food waste and consists of a theoretical and a practical part. Theoretical part aims to provide clear and complex definition of wood waste related problems, summarize current findings in Czech and foreign sources. Introduction chapter explains important terms and legal measures related to this topic. It is followed by description of causes, implications and possibilities in food waste reduction. Main goal of practical part is analyzing food waste in Czech households and providing recommendations for wood waste reduction as well as some additional measurements. Practical part contains detailed analysis of primary data acquired by questionnaires and measuring food waste in Czech households. Important results and conclusions are then processed in final chapter.

Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2017-05-30T11:58:58Z No. of bitstreams: 1 Luciano Lopes Vargas Amor_.pdf: 2139833 bytes, checksum: f496319c4cf4ede22ca6b861b4855664 (MD5) / Made available in DSpace on 2017-05-30T11:58:58Z (GMT). No. of bitstreams: 1 Luciano Lopes Vargas Amor_.pdf: 2139833 bytes, checksum: f496319c4cf4ede22ca6b861b4855664 (MD5) Previous issue date: 2017-01-12 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / CNPQ – Conselho Nacional de Desenvolvimento Científico e Tecnológico / O setor da construção civil é hoje um grande gerador de resíduos, o que impacta negativamente o meio ambiente. Tanto a fase de projeto quanto a de execução de obras podem ocasionar essa geração. Quantificar o resíduo gerado em uma obra é fundamental para ter um controle do problema. A madeira, principal material empregado no uso provisório nos canteiros de obras, pode gerar grande volume de resíduo, sendo que o mesmo é descartado tão logo a obra termina, havendo pouco reaproveitamento ou reciclagem da mesma. Quantificar esse resíduo pode facilitar a gestão e o controle do mesmo, possibilitando a sustentabilidade de um material nobre e importante para o desenvolvimento da construção civil. O objetivo deste estudo consiste em propor um modelo para estimar a geração de resíduos de madeira de uso provisório em obras de edifícios verticais, analisando suas características de projeto e de execução. A estratégia de pesquisa utilizada foi o estudo de casos múltiplos, com coleta de dados de obras localizadas na região metropolitana de Porto Alegre, feitos através de entrevistas, observações in loco e análise de projetos. Ao todo, a amostra estudada foi formada por 22 obras de 11 empresas. Como resultado, foram gerados modelos estatísticos, a partir de regressão múltipla, contendo a variável dependente - volume de resíduos de madeira – e as variáveis independentes relativas ao projeto – número de pavimentos, número de pavimentos em subsolo, volume de concreto executado – e à execução - comprimento linear de tapume em madeira, índice de uso da madeira na confecção dos equipamentos de proteção coletiva e instalações provisórias. O modelo proposto possui R² ajustado de 0,893, indicando que é capaz de explicar 89,3% do fenômeno. As variáveis que mais impactaram foram o número de pavimentos e o número de pavimentos em subsolo. O modelo permite que as empresas construtoras possuam maior controle sobre o volume de resíduo de madeira gerado pelas suas obras, e possibilita realizar ações efetivas em prol da gestão dos resíduos, havendo maior controle e a redução dos mesmos. Possibilita também aplicá-lo em outras obras de diferentes regiões, considerando as características de projeto e de execução locais. / The construction industry is today a great generator of waste, which has a negative impact on the environment. Both the design and execution phases of works can cause this generation. To quantify the waste generated in a work is fundamental to control the problem. Wood, the main material used temporarily in construction sites, can generate a large volume of waste, which is discarded as soon as the work is finished, with little reuse or recycling. Quantifying this waste can facilitate the management and control of the same, allowing the sustainability of a material which is important and noble for the development of civil construction. The aim of this study is to propose a model to estimate the generation of wood waste used temporarily in vertical construction, analyzing their design and execution characteristics. The research strategy used was the study of multiple cases, with data collection of works located in the metropolitan region of Porto Alegre, made through interviews, in situ observations and project analysis In all, the sample studied was formed by 22 works from 11 companies. As a result, statistical models were generated from multiple regression, containing the dependent variable - volume of wood waste - and the independent variables related to the project - number of floors, number of floors in subsoil, volume of concrete executed - and execution - linear length of siding in wood, the index use of wood in the production of collective protection equipment and temporary facilities. The proposed model has an adjusted R² of 0.893, indicating that it is able to explain 89.3% of the phenomenon. The variables that most impacted it were the number of floors and the number of floors in subsoil. The model allows construction companies to have greater control over the volume of wood waste generated by their works, and enables effective actions to be taken in favor of waste management, with greater control and reduction of waste. It can also be applied in other works from different regions, considering the local design and execution characteristics.

Submitted by Geyciane Santos (geyciane_thamires@hotmail.com) on 2015-09-30T15:30:42Z No. of bitstreams: 1 Dissertação - Mirian Dayse Furtado Lima.pdf: 14927258 bytes, checksum: c5d6ad1eae22a73a98998965f51d8c8b (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-09-30T19:27:42Z (GMT) No. of bitstreams: 1 Dissertação - Mirian Dayse Furtado Lima.pdf: 14927258 bytes, checksum: c5d6ad1eae22a73a98998965f51d8c8b (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-09-30T19:36:38Z (GMT) No. of bitstreams: 1 Dissertação - Mirian Dayse Furtado Lima.pdf: 14927258 bytes, checksum: c5d6ad1eae22a73a98998965f51d8c8b (MD5) / Made available in DSpace on 2015-09-30T19:36:38Z (GMT). No. of bitstreams: 1 Dissertação - Mirian Dayse Furtado Lima.pdf: 14927258 bytes, checksum: c5d6ad1eae22a73a98998965f51d8c8b (MD5) Previous issue date: 2012-07-06 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The wood processing industries use generates a timber of about 40% of the total volume of the processed timber, and the remainder in other words 60% are used in boilers and brickworks for a power generation, especially in some areas of North. However, the burning of waste wood there generating other residue, ash, whose destination is a landfill. This paper presents a study on the potential use of three types of tropical wood waste, Cumarurana (Dipteryx polyphylla), Cumaru (Dipteryx odorata) and Amapá (Brosimum parinariensis), the production of particleboard, using polyurethane resin based on castor oil as a binder. There was a chemical and physical characterization of the waste based on TAPPI standard. In the first stage waste Cumarurana panels (1000 and 1300 g) were produced by keeping the resin content 15%. The mechanical results of these panels were below the requirements of the NBR ABNT 14810-2 (2006). In the second stage panels Cumaru and Amapá were produced according to a factorial design, in different conditions of amount of residue (1000 to 1500g) and content of resin (10-15%) and these were characterized by tests based on the physical and mechanical standard NBR ABNT 14810-3 (2006). For panels Cumaru, the factorial design showed that the waste is a significant factor (95% confidence) at its maximum level (1500g) to increase the compaction ratio. Mechanical analysis (MOR, MOE and Face Screw) showed that both the residue and the resin are significant factors in the levels studied indicating that higher values are obtained at higher levels (1500 g, 15%). For all these tests the values obtained in 1500 g of panels are in accordance with normative standards. For the panels with waste Amapá by the experimental design, it was observed that the residue and the resin are significant factors, when the response variable and MOE and MOR, indicating that the best results are obtained using mechanical greater amount of waste. However, only the results of MOR for panels 1300 and 1500 g a 15% were above of the normative requirements. The internal adhesion tests were within the normative standards for both panels Cumaru and Amapá. / O processamento da madeira em indústrias madeireiras gera um aproveitamento de cerca de 40% do volume total das toras processadas, sendo que o restante, ou seja, 60% são utilizados em caldeiras e olarias para a geração de energia elétrica, principalmente em alguns locais da região Norte. No entanto, com a queima desses resíduos de madeira há a geração de outro resíduo, as cinzas, cuja destinação é o aterro. Este trabalho apresenta um estudo sobre o potencial uso de três tipos de resíduos de madeiras tropicais, Cumarurana (dipteryx polyphylla), Cumaru (Dipteryx odorata) e Amapá (Brosimum parinariensis), na produção de painéis aglomerados, utilizando resina poliuretana à base de óleo de mamona, como aglomerante. Fez-se a caracterização química e física dos resíduos baseadas na norma TAPPI. Na primeira etapa, painéis com resíduos de Cumarurana (1000 e 1300 g) foram produzidos mantendo o teor de resina em 15 %. Os resultados mecânicos desses painéis foram abaixo dos requisitos exigidos pela Norma NBR ABNT 14810-2 (2006). Na segunda etapa os painéis de Cumaru e Amapá foram produzidos seguindo planejamento fatorial, em diferentes condições de quantidade de resíduo (1000 a 1500g) e teor de resina (10 a 15%) e estes foram caracterizados através de ensaios físicos e mecânicos baseados na norma NBR ABNT 14810- 3 (2006). Para os painéis de Cumaru, o planejamento fatorial mostrou que o resíduo é um fator significante (95% confiança) no seu nível máximo (1500g) para aumentar a razão de compactação. Análises mecânicas (MOR, MOE e Arrancamento de Parafuso na Face) mostraram que tanto o resíduo quanto a resina são fatores significativos nos níveis estudados, indicando que maiores valores são obtidos em níveis mais altos (1500 g e 15%). Para todos esses ensaios os valores obtidos em painéis de 1500 g estão de acordo com os padrões normativos. Para os painéis com resíduo de Amapá, através do planejamento experimental, observou-se que o resíduo e resina são fatores significativos, quando a variável resposta é MOR e MOE, indicando que melhores resultados mecânicos são obtidos utilizando maior quantidade de resíduo. Porém, apenas os resultados de MOR, para painéis a 1300 g e 1500 g a 15% apresentaram-se acima dos requisitos normativos. Os testes de adesão interna apresentaram-se dentro dos padrões normativos, tanto para painéis de Cumaru quanto para Amapá.

At the Idbäcken combined heat and power (CHP) plant waste wood is combusted. The flue gas from the combustion is condensed and heavy metals and other toxic species ends up in the condensate water. Since the condensate water in this way contains many toxic substances it needs to be treated before it is sent to the recipient Kilaån (the Baltic Sea). Arsenic (As) is one substance that needs to be removed, and this thesis aims to find the optimal conditions for As removal by using precipitation with iron(III) chloride (FeCl3). When FeCl3 comes in contact with water it forms ferrihydrite, an efficient sorbent due to its high specific area. The adsorption of As to ferrihydrite is dependent on different variables; pH, Fe(III) dosage, competitive ions et cetera. Lab-scale experiments have shown that a pH value between 3 and 8 is required for efficient As removal. Concerning the Fe(III) dosage further experiments are needed in order to tell what dosage that is the optimal in this case. Further, the removal of metals has also been studied. A comparison between two chemicals (TMT 15 and MP 7) used for metal removal has been made, which showed that TMT 15 is to prefer for metal removal. Also, it was found that efficient removal of metals require pH > 5, preferably in the slightly alkaline pH range.

The mechanisms and kinetics of combustion of waste wood as well as the phases during combustion processes are important to eliminate these wastes without any possible damage to environment. In the present study, combustion mechanisms, activation energy and pre-exponential constants, and phases of combustion were investigated for untreated natural pine and treated Medium Density Fiberboard (MDF), plywood and particleboard samples that involve some chemicals and additives. Waste wood samples were heated in air at 10, 20 and 30oC/min heating rates in a Thermo Gravimetric Analyzer (TGA) from room temperature to 900oC. Thermogravimetry (TG) and Derivative Thermogravimetry (DTG) curves for all samples were obtained. The gases formed during combustion reactions were directly fed to a Fourier Transform Infrared Spectroscopy (FTIR) instrument coupled to TGA. Emission characteristics of the samples were determined in-situ by using the FTIR spectrums. As a result of TG analysis, thermal decomposition of treated samples was observed at lower temperatures as compared to the untreated pine sample because of the catalyzing effects of the chemicals in the treated samples. Therefore, there were less flammable products, lower weight losses in the main oxidation region, decrease in the max. weight loss temperatures and formation of more char for treated samples as compared to untreated pine sample. In other words, chemicals used during production of these samples lead to decrease in the combustibility of the treated samples. Thermal kinetic constants for the samples were calculated by using Coats Redfern and Broido Methods. In order to find out the mechanisms responsible for the oxidation of the waste wood samples in different regions, six solid state mechanisms of Coats Redfern Method were tested. As a result of FTIR analysis of the emitted gases from TG analysis, several chemical groups were detected from pine and treated samples. Combustion of all samples revealed some gases containing aromatics, C-H groups, CO2 and CO. However, there were some toxic and carcinogenic gases like formaldehyde, isocyanate group, ammonia, phenyl group and benzoylbromide among the emissions of treated samples which need utmost attention when recovering energy from treated waste woods.

The use of waste (or recycled) wood as a fuel in heat and power stations is becoming more widespread in Sweden (and Europe), because it is CO2 neutral with a lower cost than forest fuel. However, it is a heterogeneous fuel with a high amount of chlorine, alkali and heavy metals which causes more corrosion than fossil fuels or forest fuel. A part of the boiler which is subjected to a high corrosion risk is the furnace wall (or waterwall) which is formed of tubes welded together. Waterwalls are made of ferritic low-alloyed steels, due to their low price, low stress corrosion cracking risk, high heat transfer properties and low thermal expansion. However, ferritic low alloy steels corrode quickly when burning waste wood in a low NOx environment (i.e. an environment with low oxygen levels to limit the formation of NOx). Apart from pure oxidation two important forms of corrosion mechanisms are thought to occur in waste environments: chlorine corrosion and alkali corrosion. Although there is a great interest from plant owners to reduce the costs associated with furnace wall corrosion very little has been reported on wall corrosion in biomass boilers. Also corrosion mechanisms on furnace walls are usually investigated in laboratories, where interpretation of the results is easier. In power plants the interpretation is more complicated. Difficulties in the study of corrosion mechanisms are caused by several factors such as deposit composition, flue gas flow, boiler design, combustion characteristics and flue gas composition. Therefore, the corrosion varies from plant to plant and the laboratory experiments should be complemented with field tests. The present project may thus contribute to fill the power plant corrosion research gap. In this work, different kinds of samples (wall deposits, test panel tubes and corrosion probes) from Vattenfall’s Heat and Power plant in Nyköping were analysed. Coated and uncoated samples with different alloys and different times of exposure were studied by scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDX), X-ray diffraction (XRD) and light optical microscopy (LOM). The corrosive environment was also simulated by Thermo-Calc software. The results showed that a nickel alloy coating can dramatically reduce the corrosion rate. The corrosion rate of the low alloy steel tubes, steel 16Mo3, was linear and the oxide scale non-protective, but the corrosion rate of the nickel-based alloy was probably parabolic and the oxide much more protective. The nickel alloy and stainless steels showed good corrosion protection behavior in the boiler. This indicates that stainless steels could be a good (and less expensive) alternative to nickel-based alloys for protecting furnace walls. The nickel alloy coated tubes (and probe samples) were attacked by a potassium-lead combination leading to the formation of non-protective potassium lead chromate. The low alloy steel tubes corroded by chloride attack. Stainless steels were attacked by a combination of chlorides and potassium-lead. The Thermo-Calc modelling showed chlorine gas exists at extremely low levels (less than 0.1 ppm) at the tube surface; instead the hydrated form is thermodynamically favoured, i.e. gaseous hydrogen chloride. Consequently chlorine can attack low alloy steels by gaseous hydrogen chloride rather than chlorine gas as previously proposed. This is a smaller molecule than chlorine which could easily diffuse through a defect oxide of the type formed on the steel. / <p>QC 20130423</p>