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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.
1

Os planos diretores e o planejamento urbano no aglomerado Cuiaba / Várzea Grande - MT / The master plans and planning urban on agglomerate Cuiabá /Várzea Grande-MT

Garcia, Sílvia Maria Nicoletti Pillon 30 March 2010 (has links)
Os Planos Diretores têm recebido muitas críticas devido a sua ineficácia como instrumento de planejamento urbano no Brasil e por certo período ficaram em segundo plano. Com a promulgação da Lei 10.257 de 2001, chamado Estatuto da Cidade, os municípios foram obrigados a rever seus Planos Diretores para adaptá-los aos novos princípios e objetivos dessa Lei. Neste trabalho foram avaliados os Planos Diretores das cidades do Aglomerado Urbano Cuiabá e Várzea Grande Mato Grosso/Brasil. Os estudos foram a partir da realidade das cidades, das suas estruturas administrativas e do fato delas formarem um Aglomerado Urbano (atualmente Região Metropolitana do Vale do Rio Cuiabá) exigindo que muitos assuntos fossem tratados em harmonia. Foi abordado o planejamento urbano no Brasil; a história e as características de Cuiabá e Várzea Grande; a formação do Aglomerado Urbano Cuiabá Várzea Grande; a elaboração dos atuais Planos Diretores; a utilização dos instrumentos disponíveis no Estatuto da Cidade; as diretrizes para as políticas de acesso a terra urbanizada; a regularização fundiária; o saneamento ambiental; o meio ambiente e a mobilidade urbana; e as principais ações que estão sendo realizadas segundo os Planos Diretores. / The master plans have received much criticism due to their effectiveness as urban planning instrument in Brazil and by certain period were in the background. With the enactment of law 10.257/2002, called City Status, the municipalities were forced to revise their plans directors to adapt them to new principles and objectives of the law. This work have been assessed the master plans of cities and urban Cuiabá - Várzea Grande Mato Grosso - Brazil, from the study of cities, the administrative structure and form an urban cluster (currently metropolitan region Cuiabá River Valley) and many matters to be dealt with in harmony. Was approached the urban planning and examined the history and characteristics of Cuiabá and Várzea Grande; the urban cluster of Cuiabá - Várzea Grande shavings urban, the current master plans; the use of instruments available in the city\'s status; guidelines for land access policies; land regularization urbanized; environmental sanitation; the environment and urban mobility; the administrative structure of cities and the main actions that are being carried out in accordance with the master plans.
2

Os planos diretores e o planejamento urbano no aglomerado Cuiaba / Várzea Grande - MT / The master plans and planning urban on agglomerate Cuiabá /Várzea Grande-MT

Sílvia Maria Nicoletti Pillon Garcia 30 March 2010 (has links)
Os Planos Diretores têm recebido muitas críticas devido a sua ineficácia como instrumento de planejamento urbano no Brasil e por certo período ficaram em segundo plano. Com a promulgação da Lei 10.257 de 2001, chamado Estatuto da Cidade, os municípios foram obrigados a rever seus Planos Diretores para adaptá-los aos novos princípios e objetivos dessa Lei. Neste trabalho foram avaliados os Planos Diretores das cidades do Aglomerado Urbano Cuiabá e Várzea Grande Mato Grosso/Brasil. Os estudos foram a partir da realidade das cidades, das suas estruturas administrativas e do fato delas formarem um Aglomerado Urbano (atualmente Região Metropolitana do Vale do Rio Cuiabá) exigindo que muitos assuntos fossem tratados em harmonia. Foi abordado o planejamento urbano no Brasil; a história e as características de Cuiabá e Várzea Grande; a formação do Aglomerado Urbano Cuiabá Várzea Grande; a elaboração dos atuais Planos Diretores; a utilização dos instrumentos disponíveis no Estatuto da Cidade; as diretrizes para as políticas de acesso a terra urbanizada; a regularização fundiária; o saneamento ambiental; o meio ambiente e a mobilidade urbana; e as principais ações que estão sendo realizadas segundo os Planos Diretores. / The master plans have received much criticism due to their effectiveness as urban planning instrument in Brazil and by certain period were in the background. With the enactment of law 10.257/2002, called City Status, the municipalities were forced to revise their plans directors to adapt them to new principles and objectives of the law. This work have been assessed the master plans of cities and urban Cuiabá - Várzea Grande Mato Grosso - Brazil, from the study of cities, the administrative structure and form an urban cluster (currently metropolitan region Cuiabá River Valley) and many matters to be dealt with in harmony. Was approached the urban planning and examined the history and characteristics of Cuiabá and Várzea Grande; the urban cluster of Cuiabá - Várzea Grande shavings urban, the current master plans; the use of instruments available in the city\'s status; guidelines for land access policies; land regularization urbanized; environmental sanitation; the environment and urban mobility; the administrative structure of cities and the main actions that are being carried out in accordance with the master plans.
3

Effects of phosphate type, antimicrobials and processing methods on the quality, shelf-life and sensory characteristics of enhanced catfish fillets

Kin, Sovann 30 April 2011 (has links)
Catfish fillets that were enhanced with salt and various phosphate treatments through vacuum tumbling or multi-needle injection were evaluated for yield, protein exudate (only tumbling), surface color, pH, cooking loss, tenderness, purge loss and shelf-life. An agglomerated sodium phosphate blend (AGSP) was the optimum treatment for both vacuum tumbling and multi-needle injection and was further utilized in conjunction with potassium lactate (PL) and/or potassium acetate (PA) through vacuum tumbling to determine their effect on the quality, shelf-life and sensory characteristics of enhanced catfish fillets. In addition, the combination of AGSP and PA+PL that maximized shelf-life was further utilized in conjunction with liquid or wood smoking to evaluate the quality and inhibition of L. monocytogenes growth in ready-to-eat (RTE) smoked catfish fillets. All phosphate treatments increased (P<0.05) tenderness, but AGSP that contained mono-, tri-, and polyphosphates increased (P<0.05) pH and yield and decreased (P<0.05) yellowness in both tumbling and injection systems when compared to the control treatment. In addition, AGSP decreased (P<0.05) protein exudate when fillets were tumbled and increased (P<0.05) solution pick-up when injected. Psychrotrophic plate counts (PPC) for all phosphate treatments were similar to the control at each storage time and reached 7 log CFU/g by day 7 of storage; however, when AGSP was used in conjunction with PA+PL, PPC and sensory spoilage scores of raw catfish fillets were lower (P<0.05) than the control at each storage time. Marinating with a combination of 0.25% PA and 0.58% PL increased shelf-life (P<0.05) to between 10 and 14 days when compared to the control which had a shelf-life between 7 and 10 days. In addition, consumers preferred (P<0.05) fried catfish fillets that were treated with AGSP with and without PA+PL when compared to non-marinated controls with respect to appearance, flavor and overall acceptability. In conclusion, AGSP optimized yield and improved the quality of refrigerated catfish fillets, and extended shelf-life three days over other treatments when combined with PA+PL. This combined treatment also enhanced sensory properties of fried catfish fillets and had a synergistic effect with wood smoke constituents that inhibited the growth of L. monocytogenes on RTE smoked catfish fillets.
4

Reciclagem de pó de forno elétrico a arco para a produção de Aglomerado Pré-Fundido (APF) para uso em processo siderúrgico / Recycling of electric arc furnace dust for the production of agglomerated Pre-Cast Agglomerated (PCA) for use in steel making process

Araújo, José Alencastro de 27 May 2014 (has links)
O pó de forno elétrico a arco (FEA) é gerado durante a fusão de sucata ferrosa nos fornos elétricos a arco e coletado predominantemente através de filtros de mangas. Esta substância é listada como resíduo sólido perigoso de fonte específica, K061, conforme a Norma ABNT NBR 10004:2004. As maiores empresas siderúrgicas semi-integradas do mundo têm adotado para o tratamento de pó de FEA, fundamentalmente três rotas: a recuperação de zinco e chumbo, através de dois processos complementares, um piro-metalúrgico, o Wäelz kiln e outro hidro-metalúrgico, o processo de dupla lixiviação Óxido de Wäelz; a inertização através da blendagem com a cal, aditivos e água, de forma a alcançar o pH da mistura >11, o que garante que metais pesados como o chumbo, cádmio e o zinco, presentes no pó de forno elétrico, não possam se tornar solúveis, evitando consequentemente, a sua lixiviação e a disposição em aterros industriais de resíduos sólidos perigosos. Sob a perspectiva da sustentabilidade, deve ser considerada a rota da recuperação de zinco e chumbo, que para ser viável necessita reunir a geração de pó de FEA de varias plantas, o que para um país com dimensões continentais pode ser um fator de insucesso. Esse trabalho trata da reciclagem do pó de FEA através do processo de sinterização de um compósito constituído de pó de FEA aglomerado com coque, carepa e fluorita cerâmica em pelotas, aplicável a uma planta unitária. Como resultado deste processo foram obtidos dois coprodutos, o aglomerado pré-fundido, APF, com teor de óxido de ferro superior a 70%, objeto do processo de sinterização e o concentrado de zinco, com teor de óxido de zinco maior que 50%, resultante da volatilização deste metal durante o processo de sinterização e coletado através de filtro de mangas. Complementarmente foi extraído aproximadamente 90% dos óxidos de chumbo e cádmio contidos no pó de FEA inicial. A produção do APF ocorreu em escala experimental dividida em três fases, a primeira fase foi efetuada com oito formulações distintas e comprovou através de análises químicas de espectrometria por fluorescência de raios X e difratometria de raios X, a viabilidade técnica da utilização somente de resíduos sólidos industriais para fabricação do APF. A segunda fase, também com oito formulações, definidas conforme planejamento de experimentos com delineamento fatorial, teve como objetivo identificar os principais efeitos das interações entre os componentes do APF, para obtenção da mistura com formulação ótima. A terceira fase testou a intensidade das variáveis, coque e fluorita cerâmica, para a extração do zinco. As duas primeiras fases dos testes de produção em escala experimental foram realizadas em uma planta piloto de sinterização de fluxo descendente e a terceira fase em uma planta piloto de fluxo ascendente, ambas instaladas na usina ArcelorMittal Piracicaba. O APF, com a formulação ótima, foi produzido em escala industrial na planta de sinterização Metalflexi, também instalada na usina ArcelorMittal Piracicaba, e testado em alto-forno de pequeno porte. O concentrado de zinco foi caracterizado quimicamente para se avaliar o uso em segmentos industriais que utilizem este elemento. / The electric arc furnace (EAF) dust is generated during melting of steel scrap in electric arc furnaces and collected mainly through bag filters. The EAF dust is listed as hazardous waste from specific source, K061, according to ABNT 10004:2004. The major semi-integrated steel companies in the world have adopted for the treatment of EAF dust, basically three routes: the recovery of zinc and lead, through two complementary processes, a pyro-metallurgy, Waelz kiln and other hydro-metallurgical the leaching process of double oxide Waelz; the blanketing by blending with lime, water and additives in order to achieve the pH of the mixture>11, which ensures that heavy metals like lead, cadmium and zinc, present in furnace residue, can not become soluble, thereby avoiding the leaching and disposal in landfills of hazardous waste. This work suggests recycling of the EAF dust by sintering of a composite consisting of EAF dust agglomerate to coke particles (carbon source), mill scale (iron source) and ceramic fluorite (adictive agent used like fluxant) into pellets, a process known as sintering. As a result of the process is expected to obtain two by-products, the pre-cast agglomerated, PCA, with iron oxide content exceeding 70%, object of the process of sintering and zinc dust, containing more than 50% zinc oxide resulting from volatilization of this metal during the sintering process and collected by bag filter. Addition is expected to extract approximately 90% of lead and cadmium oxide contained in the initial EAF dust. The production of the PCA occurred in experimental scale divided into three stages, the first stage was performed with eight different formulations and checked by chemical analysis by X-ray fluorescence spectrometer and X-ray diffraction, the technical viability of using only solid waste industrial manufacturing PCA. The second phase, also with eight formulations, defined as planning experiments with factorial design, was tested the main effects and the double and triple interactions between the components of the PCA, to obtain the optimal formulation. The third phase was checked the intensity of the variables, coke fluorite ceramics, for removing zinc of PCA. The first two stages of the production tests were carried out on a pilot scale in a pilot plant sintering downstream and the third phase in a pilot plant xii upstream, both installed in the plant ArcelorMittal Piracicaba. The PCA, with the optimal formulation was produced on an industrial scale in the sinter plant Metalflexi also installed at the plant ArcelorMittal Piracicaba, and tested in small blast furnace. The zinc dust was characterized chemically for application in industries that use this element.
5

Instant milk powder production : determining the extent of agglomeration : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemical Technology at Massey University, Palmerston North, New Zealand

Williams, Anna M January 2007 (has links)
Agglomerated milk powders are produced to give improved properties such as flowability, dispersibility, reduced dustiness and decreased bulk density. A key function of these powders is to dissolve "instantly" upon addition to water and because of this they are also called "instant milk powders". They are produced by agglomerating the undersized fines that are returned to the top of the spray drier with milk concentrate droplet spray. Interaction occurs in a collision zone, often with multiple sprays and fines return lines. Agglomeration can be a difficult process to control and operators find it hard to fine tune the process to produce specific powder properties. This work aimed to understand the effects of key droplet and fines properties on the extent of agglomeration to allow a mechanistic understanding of the process. Three scales of spray drier were investigated in this study with different rates of evaporation; a small scale drier (0.5 - 7 kg water h-1), a pilot scale drier (80 kg water h-1) and a range of commercial production scale driers (4 - 15 000 kg water h-1). A survey of operators of commercial scale driers showed that control of instant milk powder production to influence bulk density is highly intuitive. Fines recycle rates were expected to be important in control of agglomeration processes and were estimated on a specific plant by using the pressure drop measured in the fines return line. A model based on pressure drop along a pneumatic pipeline under-predicted the experimental values for pressure drop due to solids, which means a calibration curve should be generated for each specific drier. Fines recycle rates were predicted to be significantly higher at 95 to 130 % of production rates compared to those expected by operators of 50%. Experimental measurements agreed with existing models for the effect of temperature on the density and viscosity of milk concentrates. Experimental results showed that the surface tensions of concentrated milks were within the same range as literature values for standard milks below 60°C, but were significantly higher for milk above 60°C. This is thought to be linked to the mechanism of skin formation due to disulphide cross linking at high temperatures and concentrations. Powder properties were also established for selected products produced on the commercial scale driers. These powders were then used in experiments on the two smaller driers. Because collision frequency depends on the velocity and droplet size of sprays; these properties were measured for the small scale drier and estimated, where possible, for the pilot and commercial driers. The small scale agglomerating spray drier was configured to alter droplet and particle properties when interacting a vertical fines particle curtain with a horizontal spray sheet. An extensive design and improvement process was carried out to ensure the system consistently delivered these streams in a controllable manner. The processes of collision and adhesion occur very quickly inside the spray drier. In order to assess the extent of agglomeration that has occurred, the feed streams must be compared to the final product stream. An ideal way to do this is to use an agglomeration index which compares the particle size distributions of the feed (fines recycle and spray streams) and the particle size distribution of the product stream (the agglomerated powder). The index described changes between these steams across the particle size distribution and is called an agglomeration efficiency, ξg. However, it was found that the presence of fines in the product of the one-pass design obscured the agglomerates formed. The agglomeration efficiency, ξg, was modified to become ξh which subtracted the fines stream from the agglomerated product distribution. In this way ξh models industrial operation where the fines are recycled, by effectively just comparing the spray and product streams entering and leaving the process. The small scale drier was used for an experimental study on natural and forced agglomeration, where the drier was operated with spray only, then with spray and fines. For natural agglomeration, SEM images of the product powder indicated that little agglomeration occurred between spray droplets. The product yield was unacceptably low (~ 40%) due to adhesion of spray droplets to the drying chamber wall opposing the horizontal spray. When the fines curtain was introduced in the forced agglomeration experiments, product yield increased above 50% because the fines acted as collectors for the spray droplets. However, the agglomeration performance of the modified spray drier was lower than expected. The equipment design was then optimised by considering three key issues; fines dispersion, droplet dispersion and stickiness, and agglomerate breakdown. Final experiments studied agglomeration at low fines to spray mass flux ratios and showed that increasing the fines size had a positive effect on agglomeration efficiency,ξh. The agglomeration study at pilot scale identified the effect of key variables, total solids, concentrate and fines flow rate, and fines size on the agglomeration efficiency. A dimensionless flux approach was used to explain the experimental results. The fines to spray mass flux ratio and the projected area flux ratio (at constant concentrate flow rate) were found to be the most suitable to represent the physical processes during agglomeration. Experimental results showed that a higher dimensionless flux resulted in more agglomeration and as well as small fines size and atomising low solids concentrate. The critical Stokes number highlighted the importance of particle size and collision velocity on the outcome of the collision as well as the importance of stickiness on adherence following the collision. A statistical analysis established a relational model for predicting the agglomeration efficiency based on fines size, total solids and the fines to spray mass flux ratio. This thesis has gained insight into agglomeration processes during spray drying and knowledge about how to define the extent of agglomeration. Practical findings from this research can have a significant impact on successful spray drying operation for instant powders. There are some practical steps to be taken industrially to promote the control of agglomerating spray driers. The first step is to measure and control the flow of fines recycled to the top of the spray drier. The next step is to validate the findings at industrial scale and link the agglomeration index to the bulk powder properties. However, there are many challenges that remain to be tackled in the area of milk powder agglomeration. Milk powder agglomeration at the top of the spray drier is a complex process involving many different variables. A more detailed study of the micro processes that occur during agglomeration will give increased understanding of the relationships between key operating variables and agglomerate properties.
6

Reciclagem de pó de forno elétrico a arco para a produção de Aglomerado Pré-Fundido (APF) para uso em processo siderúrgico / Recycling of electric arc furnace dust for the production of agglomerated Pre-Cast Agglomerated (PCA) for use in steel making process

José Alencastro de Araújo 27 May 2014 (has links)
O pó de forno elétrico a arco (FEA) é gerado durante a fusão de sucata ferrosa nos fornos elétricos a arco e coletado predominantemente através de filtros de mangas. Esta substância é listada como resíduo sólido perigoso de fonte específica, K061, conforme a Norma ABNT NBR 10004:2004. As maiores empresas siderúrgicas semi-integradas do mundo têm adotado para o tratamento de pó de FEA, fundamentalmente três rotas: a recuperação de zinco e chumbo, através de dois processos complementares, um piro-metalúrgico, o Wäelz kiln e outro hidro-metalúrgico, o processo de dupla lixiviação Óxido de Wäelz; a inertização através da blendagem com a cal, aditivos e água, de forma a alcançar o pH da mistura >11, o que garante que metais pesados como o chumbo, cádmio e o zinco, presentes no pó de forno elétrico, não possam se tornar solúveis, evitando consequentemente, a sua lixiviação e a disposição em aterros industriais de resíduos sólidos perigosos. Sob a perspectiva da sustentabilidade, deve ser considerada a rota da recuperação de zinco e chumbo, que para ser viável necessita reunir a geração de pó de FEA de varias plantas, o que para um país com dimensões continentais pode ser um fator de insucesso. Esse trabalho trata da reciclagem do pó de FEA através do processo de sinterização de um compósito constituído de pó de FEA aglomerado com coque, carepa e fluorita cerâmica em pelotas, aplicável a uma planta unitária. Como resultado deste processo foram obtidos dois coprodutos, o aglomerado pré-fundido, APF, com teor de óxido de ferro superior a 70%, objeto do processo de sinterização e o concentrado de zinco, com teor de óxido de zinco maior que 50%, resultante da volatilização deste metal durante o processo de sinterização e coletado através de filtro de mangas. Complementarmente foi extraído aproximadamente 90% dos óxidos de chumbo e cádmio contidos no pó de FEA inicial. A produção do APF ocorreu em escala experimental dividida em três fases, a primeira fase foi efetuada com oito formulações distintas e comprovou através de análises químicas de espectrometria por fluorescência de raios X e difratometria de raios X, a viabilidade técnica da utilização somente de resíduos sólidos industriais para fabricação do APF. A segunda fase, também com oito formulações, definidas conforme planejamento de experimentos com delineamento fatorial, teve como objetivo identificar os principais efeitos das interações entre os componentes do APF, para obtenção da mistura com formulação ótima. A terceira fase testou a intensidade das variáveis, coque e fluorita cerâmica, para a extração do zinco. As duas primeiras fases dos testes de produção em escala experimental foram realizadas em uma planta piloto de sinterização de fluxo descendente e a terceira fase em uma planta piloto de fluxo ascendente, ambas instaladas na usina ArcelorMittal Piracicaba. O APF, com a formulação ótima, foi produzido em escala industrial na planta de sinterização Metalflexi, também instalada na usina ArcelorMittal Piracicaba, e testado em alto-forno de pequeno porte. O concentrado de zinco foi caracterizado quimicamente para se avaliar o uso em segmentos industriais que utilizem este elemento. / The electric arc furnace (EAF) dust is generated during melting of steel scrap in electric arc furnaces and collected mainly through bag filters. The EAF dust is listed as hazardous waste from specific source, K061, according to ABNT 10004:2004. The major semi-integrated steel companies in the world have adopted for the treatment of EAF dust, basically three routes: the recovery of zinc and lead, through two complementary processes, a pyro-metallurgy, Waelz kiln and other hydro-metallurgical the leaching process of double oxide Waelz; the blanketing by blending with lime, water and additives in order to achieve the pH of the mixture>11, which ensures that heavy metals like lead, cadmium and zinc, present in furnace residue, can not become soluble, thereby avoiding the leaching and disposal in landfills of hazardous waste. This work suggests recycling of the EAF dust by sintering of a composite consisting of EAF dust agglomerate to coke particles (carbon source), mill scale (iron source) and ceramic fluorite (adictive agent used like fluxant) into pellets, a process known as sintering. As a result of the process is expected to obtain two by-products, the pre-cast agglomerated, PCA, with iron oxide content exceeding 70%, object of the process of sintering and zinc dust, containing more than 50% zinc oxide resulting from volatilization of this metal during the sintering process and collected by bag filter. Addition is expected to extract approximately 90% of lead and cadmium oxide contained in the initial EAF dust. The production of the PCA occurred in experimental scale divided into three stages, the first stage was performed with eight different formulations and checked by chemical analysis by X-ray fluorescence spectrometer and X-ray diffraction, the technical viability of using only solid waste industrial manufacturing PCA. The second phase, also with eight formulations, defined as planning experiments with factorial design, was tested the main effects and the double and triple interactions between the components of the PCA, to obtain the optimal formulation. The third phase was checked the intensity of the variables, coke fluorite ceramics, for removing zinc of PCA. The first two stages of the production tests were carried out on a pilot scale in a pilot plant sintering downstream and the third phase in a pilot plant xii upstream, both installed in the plant ArcelorMittal Piracicaba. The PCA, with the optimal formulation was produced on an industrial scale in the sinter plant Metalflexi also installed at the plant ArcelorMittal Piracicaba, and tested in small blast furnace. The zinc dust was characterized chemically for application in industries that use this element.
7

Estudo experimental de briquetes autorredutores e auto-aglomerantes de minério de ferro e carvão fóssil. / Experimental study of self-reducing self-agglomerated iron ore and brown coal briquettes.

Tanaka, Marcio Toshio 27 March 2014 (has links)
Este trabalho consiste no estudo da obtenção de aglomerados autorredutores na forma de briquetes a frio tratados termicamente, utilizando minério de ferro e carvão fóssil como matérias-primas. Esta promissora tecnologia tem como premissa a utilização da termo-plasticidade do carvão fóssil para conferir resistência e promover a auto-aglomeração. A obtenção de briquetes dá-se através de três etapas: condicionamento da mistura, briquetagem a frio e tratamento térmico. Os finos de carvão e minério são misturados e homogeneizados. A mistura, então, passa por processo de briquetagem a frio para compactação, promove o aumento de contato entre as partículas de carvão e minério. Finalmente tratamento térmico é realizado para obter a forma de um corpo sólido e coeso de auto-aglomerado autorredutor. O objetivo deste trabalho é determinar as melhores condições de obtenção de briquetes através do estudo de variáveis ao longo do processo de fabricação, utilizando a resistência mecânica como parâmetro. As variáveis estudadas são: granulometria do carvão, envelhecimento do carvão, percentual de carvão na mistura, adição de aglomerantes, pressão de compactação na briquetagem e temperatura de tratamento térmico. Os resultados obtidos neste estudo indicam que estas variáveis afetam significativamente a resistência mecânica. Utilizando-se o carvão Chipanga, o melhor resultado de resistência à compressão foi de 19,82 Mpa. Foram consideradas as seguintes condições de fabricação: mistura na proporção de 75:25 (% em massa) de minério para carvão Chipanga, o carvão continha finos inferiores à 0,075 mm, sem a adição de aglomerantes, e o tratamento térmico foi realizado na temperatura de máxima fluidez do carvão. Além disto, foi observado que as partículas de minério de ferro foram concentradas nas regiões periféricas do briquete após tratamento térmico, e que o envelhecimento do carvão afeta negativamente a propriedade de termo-plasticidade. / This work is focused in the study of obtaining self-reducing cold briquettes of agglomerates, by using iron ore and coal as raw materials. This promising technology has its foundation on the thermo plasticity of coal to manage high mechanical resistance when it is compared with self-reducing pellets. Three steps mainly describes how to obtaining briquettes: mixture, cold briquetting and heat treatment. Fines of raw material are mixed and cold briquetting process results in a compact mixture. This might lead to closer contact between particles of iron ore and coal. Finally, heat treatment is performed to achieve a cohesive body and solid shape containing self-reducing agglomerated. The main purpose of this job is to comprehend the fundamentals on how to obtain self-reducing cold briquettes of agglomerated carbon and iron, by understanding the background of it variables along the manufacturing process, and using mechanical resistance as reference. The variables list is: the particle size of the coal, coal aging, percentage of coal in the mixture, adding binders, briquetting pressure and temperature of heat treatment. The results of this study indicate that these variables affect significantly the mechanical strength. Using Chipanga coal, the best compressive strength achieved was 19.82 MPa. It was considered the following manufacturing variables: the mixture ratio of 75:25 (wt% of iron ore and coal), fines of coal containing less than 0.075 mm, without binders, and heat treatment was performed at the temperature of coal´s maximum fluidity. Moreover, it was observed that the particles of iron ore were concentrated in the peripheral regions of the briquette after heat treatment, and that coal´s aging negatively affects the property of thermo-plasticity.
8

Painéis aglomerados produzidos com partículas de pinus e bagaço de cana empregando-se ureia formaldeido e poliuretano à base de mamona / Particleboards produced with pine and sugarcane bagasse particles using urea formaldehyde and polyurethane based on castor oil

Buzo, Ana Laura Soler Cunha 27 July 2018 (has links)
Submitted by Ana Laura Soler Cunha Buzo (analaurasolercunha@gmail.com) on 2018-09-28T22:21:33Z No. of bitstreams: 1 DISSERTAÇÃO FINAL .pdf: 3047917 bytes, checksum: 4b9d9190322307f4e23c7de4f21936e9 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-10-01T13:05:23Z (GMT) No. of bitstreams: 1 buzo_alsc_me_ilha.pdf: 3047917 bytes, checksum: 4b9d9190322307f4e23c7de4f21936e9 (MD5) / Made available in DSpace on 2018-10-01T13:05:23Z (GMT). No. of bitstreams: 1 buzo_alsc_me_ilha.pdf: 3047917 bytes, checksum: 4b9d9190322307f4e23c7de4f21936e9 (MD5) Previous issue date: 2018-07-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O desenvolvimento de estudos para produção de derivados de madeira tem representado uma real alternativa para contribuir as políticas de sustentabilidade, principalmente de espécies arbóreas nativas. Nesse contexto, o reaproveitamento de resíduos lignocelulósicos tem contribuído como uma alternativa para a produção industrial de painéis de madeira. Dentro desse contexto este trabalho se constitui do estudo para produção e avaliação de painéis aglomerados, empregando-se partículas de bagaço de cana-de-açúcar (Saccharum officinarum) e partículas de madeira de pinus (Pinus taeda; Pinus elliottii) e utilizando-se dois tipos de aglutinantes, o Poliuretano derivado do óleo de mamona (PU-M) e a Resina Ureia-formaldeído (UF). Para produção dos painéis foram propostos diferentes tratamentos com variações entre as proporções de massas das partículas, densidade nominal dos painéis de 0,80 g/cm3 e pressão de prensagem de 50 kgf/cm2 durante 10 min. As misturas de partículas foram utilizadas com 10% de umidade para o adesivo PU-M e 3% de umidade para a resina UF ambos com um conteúdo de 10% em relação à massa seca das partículas. Para prensagem dos painéis com PU-M empregou-se 100 ºC e para os painéis com UF 130 ºC. Os painéis foram submetidos a ensaios para avaliação das propriedades físicas (densidade, umidade e inchamento) e mecânicas (módulo de elasticidade, módulo de ruptura à flexão e tração perpendicular) de acordo com a ABNT NBR 14810-1 e 2 (2013). Os resultados obtidos evidenciaram ser possível a utilização das partículas provenientes do bagaço de cana e de pinus para a produção de painéis aglomerados de alta densidade. Verificou-se que os painéis produzidos com o poliuretano apresentaram maior eficiência e suas propriedades físicas e mecânicas encontram-se compatíveis com os requisitos da Norma Brasileira para painéis do tipo P6 - Painéis estruturais para uso em condições severas de carga, em condições secas. Entretanto, verificou-se que os painéis produzidos com UF podem ser classificados como painéis do Tipo P2 - Painéis não estruturais para uso em condições secas. / The development of studies for the production of wood derivatives has represented a real alternative to improve sustainability policies, mainly of native tree species. In this context, the reuse of lignocellulosic waste has contributed as an alternative to the industrial production of wood panels. This way, this work aims to produce and evaluate chipboards using particles of sugarcane bagasse (Saccharum officinarum) and particles of pine wood (Pinus taeda; Pinus elliottii) and using two types of binders, the Polyurethane derived from castor oil (PU-Castor) and Urea formaldehyde resin (UF). Different treatments were proposed for the production of boards with variations between the particle mass ratios, panels’ nominal density of 0.80 g/cm3 and pressing pressure of 50 kgf/cm2 for 10 minutes. Particle mixtures were used at 10% moisture for the PU-Castor adhesive and 3% moisture for the UF resin both with a content of 10% relative to the dry mass of the particles. For the pressing of panels with PU-Castor was used 100 °C and of panels with UF was used 130 °C. The boards were submitted to tests to evaluate the physical properties (density, moisture and swelling after 24 hours) and mechanical (modulus of elasticity, modulus of resistance to bending and perpendicular traction) according to the ABNT NBR 14810-1 and 2 (2013). The results showed that it is possible to use particles from sugarcane bagasse and pine wood for high density chipboards production. It was found that the boards produced with polyurethane presented higher efficiency and their physical and mechanical properties are compatible with the requirements of Brazilian Standard Regulations for P6 boards (Structural boards for use under severe load conditions for dry conditions use). However, it has been found that panels made with UF can be classified as type P2 panels – Non-structural boards for dry conditions use. / CAPES - DS
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Painéis aglomerados produzidos com partículas de pinus e bagaço de cana empregando-se ureia formaldeido e poliuretano à base de mamona /

Buzo, Ana Laura Soler Cunha January 2018 (has links)
Orientador: Sérgio Augusto Mello da Silva / Resumo: O desenvolvimento de estudos para produção de derivados de madeira tem representado uma real alternativa para contribuir as políticas de sustentabilidade, principalmente de espécies arbóreas nativas. Nesse contexto, o reaproveitamento de resíduos lignocelulósicos tem contribuído como uma alternativa para a produção industrial de painéis de madeira. Dentro desse contexto este trabalho se constitui do estudo para produção e avaliação de painéis aglomerados, empregando-se partículas de bagaço de cana-de-açúcar (Saccharum officinarum) e partículas de madeira de pinus (Pinus taeda; Pinus elliottii) e utilizando-se dois tipos de aglutinantes, o Poliuretano derivado do óleo de mamona (PU-M) e a Resina Ureia-formaldeído (UF). Para produção dos painéis foram propostos diferentes tratamentos com variações entre as proporções de massas das partículas, densidade nominal dos painéis de 0,80 g/cm3 e pressão de prensagem de 50 kgf/cm2 durante 10 min. As misturas de partículas foram utilizadas com 10% de umidade para o adesivo PU-M e 3% de umidade para a resina UF ambos com um conteúdo de 10% em relação à massa seca das partículas. Para prensagem dos painéis com PU-M empregou-se 100 ºC e para os painéis com UF 130 ºC. Os painéis foram submetidos a ensaios para avaliação das propriedades físicas (densidade, umidade e inchamento) e mecânicas (módulo de elasticidade, módulo de ruptura à flexão e tração perpendicular) de acordo com a ABNT NBR 14810-1 e 2 (2013). Os resultados obtidos evidenciara... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The development of studies for the production of wood derivatives has represented a real alternative to improve sustainability policies, mainly of native tree species. In this context, the reuse of lignocellulosic waste has contributed as an alternative to the industrial production of wood panels. This way, this work aims to produce and evaluate chipboards using particles of sugarcane bagasse (Saccharum officinarum) and particles of pine wood (Pinus taeda; Pinus elliottii) and using two types of binders, the Polyurethane derived from castor oil (PU-Castor) and Urea formaldehyde resin (UF). Different treatments were proposed for the production of boards with variations between the particle mass ratios, panels’ nominal density of 0.80 g/cm3 and pressing pressure of 50 kgf/cm2 for 10 minutes. Particle mixtures were used at 10% moisture for the PU-Castor adhesive and 3% moisture for the UF resin both with a content of 10% relative to the dry mass of the particles. For the pressing of panels with PU-Castor was used 100 °C and of panels with UF was used 130 °C. The boards were submitted to tests to evaluate the physical properties (density, moisture and swelling after 24 hours) and mechanical (modulus of elasticity, modulus of resistance to bending and perpendicular traction) according to the ABNT NBR 14810-1 and 2 (2013). The results showed that it is possible to use particles from sugarcane bagasse and pine wood for high density chipboards production. It was found that the boards... (Complete abstract click electronic access below) / Mestre
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Estudo experimental de briquetes autorredutores e auto-aglomerantes de minério de ferro e carvão fóssil. / Experimental study of self-reducing self-agglomerated iron ore and brown coal briquettes.

Marcio Toshio Tanaka 27 March 2014 (has links)
Este trabalho consiste no estudo da obtenção de aglomerados autorredutores na forma de briquetes a frio tratados termicamente, utilizando minério de ferro e carvão fóssil como matérias-primas. Esta promissora tecnologia tem como premissa a utilização da termo-plasticidade do carvão fóssil para conferir resistência e promover a auto-aglomeração. A obtenção de briquetes dá-se através de três etapas: condicionamento da mistura, briquetagem a frio e tratamento térmico. Os finos de carvão e minério são misturados e homogeneizados. A mistura, então, passa por processo de briquetagem a frio para compactação, promove o aumento de contato entre as partículas de carvão e minério. Finalmente tratamento térmico é realizado para obter a forma de um corpo sólido e coeso de auto-aglomerado autorredutor. O objetivo deste trabalho é determinar as melhores condições de obtenção de briquetes através do estudo de variáveis ao longo do processo de fabricação, utilizando a resistência mecânica como parâmetro. As variáveis estudadas são: granulometria do carvão, envelhecimento do carvão, percentual de carvão na mistura, adição de aglomerantes, pressão de compactação na briquetagem e temperatura de tratamento térmico. Os resultados obtidos neste estudo indicam que estas variáveis afetam significativamente a resistência mecânica. Utilizando-se o carvão Chipanga, o melhor resultado de resistência à compressão foi de 19,82 Mpa. Foram consideradas as seguintes condições de fabricação: mistura na proporção de 75:25 (% em massa) de minério para carvão Chipanga, o carvão continha finos inferiores à 0,075 mm, sem a adição de aglomerantes, e o tratamento térmico foi realizado na temperatura de máxima fluidez do carvão. Além disto, foi observado que as partículas de minério de ferro foram concentradas nas regiões periféricas do briquete após tratamento térmico, e que o envelhecimento do carvão afeta negativamente a propriedade de termo-plasticidade. / This work is focused in the study of obtaining self-reducing cold briquettes of agglomerates, by using iron ore and coal as raw materials. This promising technology has its foundation on the thermo plasticity of coal to manage high mechanical resistance when it is compared with self-reducing pellets. Three steps mainly describes how to obtaining briquettes: mixture, cold briquetting and heat treatment. Fines of raw material are mixed and cold briquetting process results in a compact mixture. This might lead to closer contact between particles of iron ore and coal. Finally, heat treatment is performed to achieve a cohesive body and solid shape containing self-reducing agglomerated. The main purpose of this job is to comprehend the fundamentals on how to obtain self-reducing cold briquettes of agglomerated carbon and iron, by understanding the background of it variables along the manufacturing process, and using mechanical resistance as reference. The variables list is: the particle size of the coal, coal aging, percentage of coal in the mixture, adding binders, briquetting pressure and temperature of heat treatment. The results of this study indicate that these variables affect significantly the mechanical strength. Using Chipanga coal, the best compressive strength achieved was 19.82 MPa. It was considered the following manufacturing variables: the mixture ratio of 75:25 (wt% of iron ore and coal), fines of coal containing less than 0.075 mm, without binders, and heat treatment was performed at the temperature of coal´s maximum fluidity. Moreover, it was observed that the particles of iron ore were concentrated in the peripheral regions of the briquette after heat treatment, and that coal´s aging negatively affects the property of thermo-plasticity.

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