935 resultados para 091210 Timber Pulp and Paper


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A recuperação de áreas degradadas é um processo lento e requer a adição de resíduos orgânicos como condicionador das propriedades físicas do solo. O lodo de esgoto apresenta elevados teores de matéria orgânica (MO) e nutrientes e, portanto, tem alto potencial para utilização nessas áreas. O objetivo deste trabalho foi verificar o efeito da adição de lodo de esgoto na recuperação das características físicas de um solo degradado (Neossolo Quartzarênico) plantado com espécies nativas da Mata Atlântica, na Fazenda Entre-Rios, pertencente à Cia. Suzano Bahia Sul de Papel e Celulose, na região de Itatinga-SP. O experimento foi conduzido em blocos casualizados com quatro repetições. Os tratamentos foram constituídos por seis doses de lodo de esgoto (0, 2,5, 5, 10, 15 e 20 t ha-1), mais um que recebeu a adubação química. A aplicação de lodo de esgoto, para recuperação de áreas degradadas, aumentou os agregados do solo conforme o aumento das doses de lodo, até 12 meses após sua aplicação. As porosidades (macro, micro e total) do solo foram aumentadas com as maiores doses de lodo de esgoto até seis meses após sua aplicação; apenas a microporosidade foi aumentada até 12 meses após a aplicação. Houve aumento da umidade do solo em função do aumento das doses de lodo no solo até seis meses após a aplicação.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Thermoeconomic Functional Analysis is a method developed for the analysis and optimal design of improvement of thermal systems (Frangopoulos, 1984). The purpose of this work is to discuss the cogeneration system optimization using a condensing steam turbine with two extractions. This cogeneration system is a rational alternative in pulp and paper plants in regard to the Brazilian conditions. The objective of this optimization consists of minimizing the global cost of the system acquisition and operation, based on the parametrization of actual data from a cellulose plant with a daily production of 1000 tons. Among the several possible decision variables, the pressure and temperature of live steam were selected. These variables significantly affect the energy performance of the cogeneration system. The conditions which determine a lower cost for the system are presented in conclusion.

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Cogeneration system design deals with several parameters in the synthesis phase, where not only a thermal cycle must be indicated but the general arrangement, type, capacity and number of machines need to be defined. This problem is not trivial because many parameters are considered as goals in the project. An optimization technique that considers costs and revenues, reliability, pollutant emissions and exergetic efficiency as goals to be reached in the synthesis phase of a cogeneration system design process is presented. A discussion of appropriated values and the results for a pulp and paper plant integration to a cogeneration system are shown in order to illustrate the proposed methodology.

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Cogeneration system design deals with several parameters in the synthesis phase, where not only a thermal cycle must be indicated but the general arrangement, type, capacity and number of machines need to be defined. This problem is not trivial because many parameters are considered as goals in the project. An optimization technique that considers costs and revenues, reliability, pollutant emissions and exergetic efficiency as goals to be reached in the synthesis phase of a cogeneration system design process is presented. A discussion of appropriated values and the results for a pulp and paper plant integration to a cogeneration system are shown in order to illustrate the proposed methodology.

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Recognizing the great potential of this residue to increase the eucalyptus forests produtivity - when used in its humidified form - the main objective of this project was to decompose the solid residues generated at Luiz Antonio mill, in a fast and artificial way, by means of piles or ridges of composted materials. The materials used in this composting process were: activated sludge, dregs and grits, wood ash and biomass. Applications of both phosphorus and potassium have been used during the planting phase. Nitrogen, in the form of urea, has been applied in two treatments with the main purpose to decrease the C/N ratio and to speed up the decomposition process. The experiment was carried out in 120 days. The best results were obtained in residue piles with a 3:1 ratio, i.e., 75% residues + 25% biomass. This mixture provided an extremely good aeration, thus enabling an appropriate material mixing and homogenization. Under the technological viewpoint, the results obtained from the composting process were quite satisfactory for VCP industrial residues treatment. This composting process enabled a material accelerated stabilization (lower C/N ratio) and homogenization. After this experiment, it became possible to use all residues just as they were generated by Luiz Antônio pulp and paper mill. This project is of the utmost relevance to VCP's forestry department as far as a significant amount of nutrients is getting back to the soil in the form of mineral and organic materials.

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Biopulping is a technology which application can be advantageous to mechanical or chemical pulping. It presents benefits such as the creation of stronger pulp, as well as energy or chemicals savings. This paper gives an overview of the recent efforts to develop biopulping processes in Brazil as well as provides critical information on biopulping development worldwide. Eucalyptus grandis wood chips have been biotreated by Ceriporiopsis subvermispora in a 50-ton biopulping pilot-plant and used to produce TMP and CTMP pulps on a mill scale, Up to 18% and 27% energy savings have been observed for producing 450-470 CSFreeness TMP and CTMP pulps. Despite darker bio-TMP pulps are produced, one-stage bleaching with 5% H2O2 was sufficient to improve brightness values to 70% and 72% for bio-TMP and control pulps, respectively. Understanding biopulping mechanisms is also relevant because more resistant and competitive fungal species could be selected with basis on a function-directed screen-ing project. As far as the chemical changes induced by the fungus in wood are concerned, recent efforts have pointed out for two different types of wood transformations. One of them involves intense lignin depolymerization in short biotreatment periods, while the other indicates that esterification reactions of oxalate secreted by the Jungas on the polysaccharides chains increase the water saturation point of the fibers. Both transformations are expected to affect the fiber-fiber bonding and, consequently, the physical resistance of wood.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Se aborda el binomio cadenas productivas y territorio, identificándose dos tipos de desarrollo: el "enclave" del Secano Interior y el de "encadenamiento potencial" entre dicho enclave y la Conurbación del Gran Concepción. Los beneficios de la cadena productiva forestal-celulosa, de importancia mundial, no llegan a su territorio, que permanece en la precariedad. El Gran Concepción, segunda conurbación industrial de importancia nacional, no logra conectarse virtuosamente con su entorno cercano mediante sus redes económicas, ni tampoco con la cadena forestal-celulosa del Secano Interior. El artículo se basa en datos de flujos económicos a partir de la matriz insumo-producto de 2008, en encuestas efectuadas en el contexto de un proyecto del Fondo Nacional de Desarrollo Regional (FNDR, 2008), y en el estudio sobre Chile y sus tipos de desarrollo (Falabella, 2000 y 2002). Finalmente, se plantea la necesidad de generar una plataforma política territorial para el desarrollo económico que facilite la rearticulación productiva.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Agronomia - FEIS

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Agronomia (Energia na Agricultura) - FCA

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)