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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.
21

Produ??o de enzimas celulol?ticas e xilanol?ticas por fungos filamentosos utilizando res?duos da cadeia do biodiesel como fonte de carbono / Production of cellulolytic and xylanolytic enzymes by filamentous fungi utilizing wastes from biodiesel production chain as carbon source

Santos, Ricardo Salviano dos 11 December 2012 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-19T13:34:44Z No. of bitstreams: 5 ric.pdf: 5207435 bytes, checksum: f03a11b8bcdc89eef456751ccb1f74f2 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-20T10:28:40Z (GMT) No. of bitstreams: 5 ric.pdf: 5207435 bytes, checksum: f03a11b8bcdc89eef456751ccb1f74f2 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Made available in DSpace on 2015-02-20T10:28:40Z (GMT). No. of bitstreams: 5 ric.pdf: 5207435 bytes, checksum: f03a11b8bcdc89eef456751ccb1f74f2 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) Previous issue date: 2013-09-20 / A pesquisa b?sica e aplicada voltada para o conhecimento e produ??o de celulases e xilanases microbianas constituem-se em valorosa a??o para o desenvolvimento de produtos e processos biotecnol?gicos. Estas enzimas t?m sido utilizadas na ind?stria de alimentos, cervejarias, vin?colas, produ??o de ra??o, ind?stria t?xtil e fabrica??o de papel. A demanda por tais catalisadores tem crescido rapidamente, encorajada principalmente pela ind?stria de biocombust?veis, em especial para a produ??o de etanol de 2? Gera??o. Neste contexto, o objetivo deste trabalho foi produzir enzimas celulol?ticas e xilanol?ticas com o uso de fungos filamentosos de ocorr?ncia natural, utilizando res?duos s?lidos da cadeia produtiva do biodiesel como fontes de carbono. Tr?s linhagens de fungos filamentosos isoladas de amostras ambientais foram avaliadas para produ??o de celulases e xilanases. Como par?metro de compara??o, utilizou-se o Trichoderma reesei CCT2768, linhagem conhecida como produtora de celulases. Dentre as linhagens avaliadas, um isolado denominado Aspergillus sp AN1257 foi o que se destacou para a produ??o de enzimas celulol?ticas e xilanol?ticas, superando inclusive a produ??o de celulases por T. reesei nas mesmas condi??es fermentativas. A fonte de carbono que melhor induziu a produ??o das enzimas investigadas pelo Aspergillus sp AN1257 foi a torta de caro?o de algod?o. Em busca da condi??o ?tima para a produ??o das enzimas estudadas foi realizado um planejamento fatorial e posteriormente aplicado um delineamento composto central rotacional (DCCR). Ap?s a aplica??o das condi??es ?timas para a produ??o enzim?tica desejada, o extrato obtido apresentou valores de 3,12 U/mL para atividade endoglucan?sica e 76,4 U/mL para a atividade xilan?sica. O extrato enzim?tico produzido apresentou atividade promissora quando utilizado na hidr?lise de lignocelulose em alguns res?duos agroindustriais. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2012. / ABSTRACT The basic and applied research focused on the knowledge and production of microbial cellulases and xylanases constitute a valuable action for the development of biotechnology products and processes. These enzymes have been used in the food industry, breweries, wineries, feed production, textile and paper manufacturing. The demand for such catalysts has grown rapidly, encouraged mainly by the biofuels industry, in particular for the production of 2nd Generation ethanol. In this context, the aim of this work was to produce cellulolytic and xylanolytic enzymes using naturally occurring filamentous fungi and solid waste of the biodiesel productive chain as carbon source. Three strains of filamentous fungi isolated from ambient samples have been evaluated for production of cellulases and xylanases. As reference microbial strain, it was used Trichoderma reesei CCT2768, known a good producer of cellulases. Among the strains tested, an isolated named Aspergillus sp AN1257 stood out for the production of cellulolytic and xylanolytic activity, surpassing even the production of cellulases by T. reesei under the same fermentation conditions. The carbon source which better induced the production of the investigated enzymes by Aspergillus sp AN1257 was cottonseed cake. In search of the optimum condition for the production of the investigated enzymes it was performed a factorial design and then it was applied a rotational central composite design (RCCD). After application of optimal condiction for enzyme production, the extract obtained showed values ??of 3.12 U/mL for endoglucanasic activity and 76.4 U/mL for xylanolytic activity. The enzyme extract produced showed promising application when used in the hydrolysis of lignocellulose in some agro-industrial residues.
22

Pir?lise t?rmica e catal?tica de res?duos de v?cuo gerados no refino de petr?leo

Lima, Regineide de Oliveira 17 February 2012 (has links)
Made available in DSpace on 2014-12-17T14:08:50Z (GMT). No. of bitstreams: 1 RegineideOL_DISSERT.pdf: 1906684 bytes, checksum: 6ab6bc4b30db454754e3cd6ba142d8d7 (MD5) Previous issue date: 2012-02-17 / In this study, was used a very promising technique called of pyrolysis, which can be used for obtaining products with higher added value. From oils and residues, since the contribution of heavier oils and residues has intensified to the world refining industry, due to the growing demand for fuel, for example, liquid hydrocarbons in the range of gasoline and diesel. The catalytic pyrolysis of vacuum residues was performed with the use of a mesoporous material belonging the M41S family, which was discovered in the early 90s by researchers Mobil Oil Corporation, allowing new perspectives in the field of catalysis. One of the most important members of this family is the MCM-41, which has a hexagonal arrangement of mesopores with pore diameters between 2 and 10 nm and a high specific surface area, making it very promising for use as a catalyst in petroleum refining for catalytic cracking, and their mesopores facilitate the access of large hydrocarbon molecules. The addition of aluminum in the structure of MCM-41 increases the acidity of the material, making it more positive for application in the petrochemical industry. The mesoporous material of the type Al-MCM41 (ratio Si / Al = 50) was synthesized by hydrothermal method starting from the silica gel, NaOH and distilled water added to the gel pseudobohemita synthesis. Driver was used as structural CTMABr. Removal of organic driver (CTMABr) was observed by TG / DTG and FTIR, but this material was characterized by XRD, which was observed the formation of the main peaks characteristic of mesoporous materials. The analysis of adsorption / desorption of nitrogen this material textural parameters were determined. The vacuum residues (VR's) that are products of the bottom of the vacuum distillation tower used in this study are different from oil fields (regions of Cear? and Rio de Janeiro). Previously characterized by various techniques such as FTIR, viscosity, density, SARA, elemental analysis and thermogravimetry, which was performed by thermal and catalytic degradation of vacuum residues. The effect of AlMCM-41 was satisfactory, since promoted a decrease in certain ranges of temperature required in the process of conversion of hydrocarbons, but also promoted a decrease in energy required in the process. Thus enabling lower costs related to energy expenditure from degradation during processing of the waste / No presente trabalho, foi utilizada uma t?cnica bastante promissora denominada de pir?lise, a qual pode ser usada para obten??o de produtos com maior valor agregado. Partindo de ?leos e res?duos, visto que a contribui??o desses petr?leos mais pesados e res?duos tem se intensificado para o mundo da ind?stria do refino, em virtude da crescente demanda por combust?veis, como por exemplo, hidrocarbonetos l?quidos na faixa de gasolina e ?leo diesel. Os res?duos de v?cuo (RV?S) que s?o produtos de fundo da torre de destila??o a v?cuo utilizados neste trabalho, foram provenientes de diferentes petr?leos (regi?es do Cear? e Rio de Janeiro). Estes res?duos foram previamente caracterizados por v?rias t?cnicas como: FTIR, viscosidade, densidade, SARA, an?lise elementar e termogravimetria, pela qual foi realizada a degrada??o t?rmica e catal?tica dos res?duos de v?cuo. A pir?lise catal?tica dos res?duos de v?cuo foi realizada com a utiliza??o de um material mesoporoso pertencente ? fam?lia M41S, que foi descoberto no in?cio dos anos 90 por pesquisadores da Mobil Oil Corporation, possibilitando assim novas perspectivas no ramo da cat?lise. Um dos mais importantes membros desta fam?lia ? o MCM-41, que possui um arranjo hexagonal de mesoporos com di?metros de poros entre 2 a 10 nm e uma alta ?rea espec?fica, tornando-o bastante promissor para ser utilizado como catalisador no refino do petr?leo para o craqueamento catal?tico, j? que seus mesoporos facilitam o acesso de mol?culas grandes de hidrocarbonetos. A incorpora??o do alum?nio na rede do material MCM-41 proporciona a acidez ao material, possibilitando sua aplica??o na ind?stria petroqu?mica. O material mesoporoso do tipo Al- MCM41 (raz?o Si/Al=50) foi sintetizado atrav?s do m?todo hidrot?rmico partindo da S?lica gel, NaOH e ?gua destilada, acrescentado de pseudobohemita no gel de s?ntese. O efeito do AlMCM-41 foi satisfat?rio, pois promoveu uma diminui??o de determinadas faixas de temperatura requeridas no processo de convers?es dos hidrocarbonetos, como tamb?m promoveu uma diminui??o na energia necess?ria do processo. Possibilitando assim, menos custos relacionados ao gasto de energia para a degrada??o durante o processamento desses res?duos. Como direcionador estrutural foi utilizado CTMABr. A remo??o do direcionador org?nico (CTMABr) foi verificado por TG/DTG e FTIR, como tamb?m este material foi caracterizado por DRX, o qual foi constatado a forma??o dos principais picos caracter?sticos dos materiais mesoporosos. Pela an?lise de adsor??o/dessor??o de nitrog?nio deste material foram determinados os par?metros texturais
23

Caracteriza??o mec?nica, t?rmica e ac?stica de um comp?sito que utiliza rejeitos de m?rmore, granito e EPS para a fabrica??o de blocos para a constru??o civil

Santos, Natanaeyfle Randemberg Gomes dos 05 February 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-02-01T21:32:18Z No. of bitstreams: 1 NatanaeyfleRandembergGomesDosSantos_TESE.pdf: 3542697 bytes, checksum: 97843b739f0b1a5bdcb53b7f88ac2d7a (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2016-02-16T20:41:39Z (GMT) No. of bitstreams: 1 NatanaeyfleRandembergGomesDosSantos_TESE.pdf: 3542697 bytes, checksum: 97843b739f0b1a5bdcb53b7f88ac2d7a (MD5) / Made available in DSpace on 2016-02-16T20:41:39Z (GMT). No. of bitstreams: 1 NatanaeyfleRandembergGomesDosSantos_TESE.pdf: 3542697 bytes, checksum: 97843b739f0b1a5bdcb53b7f88ac2d7a (MD5) Previous issue date: 2015-02-05 / A utiliza??o de materiais comp?sitos para a constru??o civil tem sido tema de in?meros trabalhos cient?ficos no Brasil e no mundo. Um dos fatores que motivam essa busca ? o d?ficit habitacional que os pa?ses principalmente do terceiro mundo enfrentam. No Brasil esse d?ficit alcan?a mais de 6,5 milh?es de moradias, em torno de 12% dos domic?lios do pa?s. Esse trabalho apresenta um comp?sito que foi obtido a partir de res?duos gerados nos processos de obten??o de placas de granito e m?rmore, cimento, gesso, areia, EPS triturado e ?gua. Esses res?duos causam grandes danos ao meio ambiente e s?o jogados em aterros em grandes quantidades. O ineditismo do trabalho est? no estudo combinado t?rmico, mec?nico e ac?stica do comp?sito obtido, em situa??o real, de c?modos que fazem parte de uma habita??o experimental. Foram confeccionados diversos blocos a partir de composi??es variadas e foram efetuados testes preliminares de resist?ncia mec?nica e t?rmica, escolhendo-se a propor??o mais apropriada. Ser?o apresentados os processos de fabrica??o e montagem dos blocos produzidos, em n?mero de 500, para a fabrica??o de uma resid?ncia experimental. Estudou-se qual o tipo de bloco e de res?duo, m?rmore ou granito, apresentou-se mais vi?vel para o fim proposto. A resist?ncia mec?nica dos blocos produzidos esteve acima de 3,0 MPa. A resist?ncia t?rmica dos blocos foi comprovada pela diferen?a m?xima entre as paredes interna e externa dos c?modos edificados em torno 8,0 ?C. A absor??o ac?stica para o c?modo mais eficiente ficou em torno 31. Demonstrou-se a viabilidade de utiliza??o dos blocos fabricados com o material comp?sito proposto para a constru??o civil. / The use of composite materials for the construction industry has been the subject of numerous scientific papers in Brazil and in the world. One of the factors that motivate this quest is the housing deficit that countries especially the third world face. In Brazil this deficit reaches more than 6.5 million homes, around 12% of all US households . This paper presents a composite that was obtained from waste generated in processes for the production of granite and marble slabs, cement, gypsum, sand, crushed EPS and water. These wastes cause great damage to the environment and are thrown into landfi lls in bulk. The novelty of the work is in the combined study thermal, mechanical and acoustic composite obtained in real situation of rooms that are part of an experimental housing. Many blocks were made from cement compositions, plaster, foam, sand, marb le and / or granite, preliminary tests of mechanical and thermal resistance were made by choosing the most appropriate proportion. Will be given the manufacturing processes and assembly units 500 units 10 x 80 x 28 cm produced for the construction of an ex perimental home. We studied what kind of block and residue, marble or granite, made it more feasible for the intended purpose. The mechanical strength of the produced blocks were above 3.0 MPa. The thermal resistance of the blocks was confirmed by the maxi mum temperature difference between the inner and outer walls of rooms built around 8.0 ? C. The sound absorption for optimal room was around 31%. Demonstrated the feasibility of using the blocks manufactured with composite material proposed for construction.
24

Caracteriza??o de ?gua de lavagem de filtros em esta??es de tratamento de ?gua de filtra??o direta

Campos, Hilderica Lima 09 February 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-02-05T22:39:44Z No. of bitstreams: 1 HildericaLimaCampos_DISSERT.pdf: 1518298 bytes, checksum: 41cac6ede5b5c76dd7cadea1205d049e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-02-16T19:46:12Z (GMT) No. of bitstreams: 1 HildericaLimaCampos_DISSERT.pdf: 1518298 bytes, checksum: 41cac6ede5b5c76dd7cadea1205d049e (MD5) / Made available in DSpace on 2016-02-16T19:46:12Z (GMT). No. of bitstreams: 1 HildericaLimaCampos_DISSERT.pdf: 1518298 bytes, checksum: 41cac6ede5b5c76dd7cadea1205d049e (MD5) Previous issue date: 2015-02-09 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / O tratamento de ?gua para abastecimento ? considerado como um grande benef?cio, tendo em vista que, se for realizado de forma eficiente, propicia sa?de ?s pessoas. Entretanto, ao considerar que uma ETA (Esta??o de Tratamento de ?gua) ? uma ind?stria, pois em seu processo produtivo h? insumos e res?duos, ? necess?rio que haja avalia??o e monitoramento constantes em cada ETA para verificar a melhor e mais adequada maneira de tratar e dispor seus res?duos, minimizando, portanto, os potenciais impactos ao meio ambiente. Os res?duos mais relevantes em ETA de filtra??o r?pida s?o os provenientes das ?guas de lavagem de filtros. A realidade mais observada em nosso pa?s ? o lan?amento destes res?duos (sem tratamento) em mananciais, os quais s?o utilizados, na maioria das vezes, como fonte de abastecimento de uma popula??o a jusante. O presente estudo avaliou indicadores quantitativos e qualitativos de ?gua de lavagem de filtros em tr?s ETA - Itaitinga, Maranguape e Pacatuba. Verificou-se que a ETA Maranguape, em termos de capacidade instalada, ? a de maior porte. A ETA Itaitinga ? a que mais consome ?gua na lavagem de filtros. A ETA Pacatuba exibiu maior concentra??o de s?lidos sediment?veis e suspensos totais, al?m de demanda qu?mica de oxig?nio e alum?nio na ?gua de lavagem dos filtros. Os par?metros s?lidos sediment?veis e s?lidos suspensos totais de todas as ETA estavam fora do padr?o de lan?amento de efluentes em corpo aqu?tico preconizado pela resolu??o 154/2002 da SEMACE (Superintend?ncia Estadual do Meio Ambiente do Cear?). Conclui-se que a ?gua de lavagem dos filtros das ETA em estudo ultrapassam os valores permitidos em legisla??o para serem descartados diretamente em manancial. Sugere-se como alternativa de tratamento de res?duos, a constru??o de lagoas de sedimenta??o de lodo e ainda, como forma de reaproveitamento da ?gua, o processo de recircula??o. / The water supply and treatment is considered as a great benefit considering that, if done efficiently, provides public health. However, considering the WTP (Water Treatment Plant) is an industry, with its inputs and waste generation, they must be constantly evaluated and monitored to verify the best and most appropriate way to process and dispose their waste, minimizing therefore the potential impacts to the environment. By volume, the most significant waste is the rapid filter backwash water. It is very common the disposal of this waste without treatment in water sources, which are used, for the most part, as a water supply source of a downstream population. This study evaluated quantitative and qualitative parameters in filter backwash water in three WTP - Itaitinga, Maranguape and Pacatuba, located in Cear? State, northeast of Brazil. It was found that the Maranguape WTP, in terms of treatment capacity, is the larger. The Itaitinga WTP is the one that consumes more water during filters washing. The Pacatuba WTP exhibited higher concentration of total suspended and settleable solids, COD and aluminum in the filters backwash water. It is noteworthy that the settleable solids and total suspended solids in all three WTP are above the effluent discharge standard recommended by Resolution 154/2002 of SEMACE (State Superintendent of Environment of Cear?). It was concluded that the filter backwash water from the study WTP exceeded the allowed values for legislation to be disposed directly into surface water bodies. It is suggested as an alternative to treat and recycle the filter backwashing water the construction of sludge settling ponds.
25

Estudo da adi??o de res?duos de quartzitos para obten??o de gr?s porcelanato

Souza, Marcondes Mendes de 17 April 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-04-08T23:17:04Z No. of bitstreams: 1 MarcondesMendesDeSouza_TESE.pdf: 3135857 bytes, checksum: 11e52ad3f92073cb71b4e3869890ab67 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-04-11T23:07:06Z (GMT) No. of bitstreams: 1 MarcondesMendesDeSouza_TESE.pdf: 3135857 bytes, checksum: 11e52ad3f92073cb71b4e3869890ab67 (MD5) / Made available in DSpace on 2016-04-11T23:07:06Z (GMT). No. of bitstreams: 1 MarcondesMendesDeSouza_TESE.pdf: 3135857 bytes, checksum: 11e52ad3f92073cb71b4e3869890ab67 (MD5) Previous issue date: 2015-04-17 / Nos estados da Para?ba e Rio Grande do Norte, no Brasil, as jazidas mais expressivas na produ??o de minerais industriais n?o-met?licos s?o as dos pegmatitos, quartzitos e granitos, que est?o localizadas na regi?o do Serid?. Os munic?pios de V?rzea - PB, Ouro Branco - RN e Parelhas - RN s?o os principais respons?veis pela extra??o de argila, quartzo, micas e feldspato. As empresas de minera??o que atuam na extra??o e beneficiamento dos quartzitos geram grandes volumes de res?duos, constituindo cerca de 90% de SiO2 na sua composi??o qu?mica proveniente do quartzo, que ? um dos constituintes b?sicos nas formula??es das massas cer?micas para a produ??o de revestimento cer?micos. Para tanto, este trabalho avalia o estudo da adi??o de res?duos de quartzito para obten??o do gr?s porcelanato atrav?s da caracteriza??o das mat?rias-primas por FRX, DRX, MEV, AG, ATG e DSC, utilizando cinco formula??es contendo 57% de feldspato, 37% de argila e 6% de res?duos de quartzitos com colora??es diferentes (branco, dourado, rosa, verde e preto), que foram sinterizadas em tr?s temperaturas: 1150?C, 1200?C e 1250?C, com isoterma de 1 hora e taxa de aquecimento de 10? C/min. Ap?s a sinteriza??o, os corpos-de-prova foram submetidos a ensaios de caracteriza??o f?sica como: absor??o de ?gua, retra??o linear, porosidade aparente, massa espec?fica aparente, resist?ncia ? flex?o em tr?s pontos. Os resultados obtidos apontavam para a possibilidade da utiliza??o do res?duo de quartzito em um percentual de 6% de adi??o na massa cer?mica. A utiliza??o de res?duos de quartzito em massa cer?mica proporcionou um produto final com propriedades tecnol?gicas que atendem ?s normas t?cnicas para a produ??o de gr?s porcelanato, sendo a temperatura de 1200?Ca que apresentou melhores resultados. De acordo com os resultados obtidos verificou-se um alto teor de ?xido de ferro no quartzito preto, sendo descartada a utiliza??o do mesmo em gr?s porcelanato por quest?o estrutural, pois o material fundiu a 1250?C. Todas as formula??es dos quartzitos obtiveram baixa absor??o de ?gua quando sinterizadas a 1200?C, obtendo AA entre 0,1% a 0,36% sem terem passado pelo processo de atomiza??o. Nos ensaios de resist?ncia ? flex?o todos os quartzitos encontram-se nos limites de aceita??o, segundo a norma europeia EN 100, superando 27 MPa na sinteriza??o a 1200?C. Com isso, o uso de res?duo de quartzito em massas cer?micas se apresenta como excelente potencial para a produ??o de gr?s porcelanato. / In States of Para?ba (PB) and Rio Grande do Norte (RN), northeast of Brazil, the most significant deposits of non-metallic industrial minerals are pegmatites, quartzites and granites, which are located in Serid? region. Extraction of clay, quartz, micas and feldspars occurs mainly in the cities of V?rzea (PB), OuroBranco (RN) and Parelhas (RN). Mining companies working in the extraction and processing of quartzite generate large volumes of waste containing about 90% SiO2 in their chemical composition coming from quartz that is one of the basic constituents of ceramic mass for the production of ceramic coating. Therefore, this work evaluates the utilization of these wastes on fabrication of high-quality ceramic products, such as porcelain stoneware, in industrial scale. Characterization of raw materials was based on XRF, XRD, GA, TGA and DSC analysis, on samples composed by 57% of feldspar, 37% of argil and 6% of quartzite residues, with 5 different colors (white, gold, pink, green and black). Samples were synthesized in three temperatures, 1150?C, 1200?C and 1250?C, with one hour isotherm and warming-up tax of 10?C/min. After synthesizing, the specimens were submit to physical characterization tests of water absorption, linear shrinkage, apparently porosity, density, flexural strain at three points. The addition of 6% of quartzite residue to ceramic mass provided a final product with technological properties attending technical norms for the production of porcelain stoneware; best results were observed at a temperature of 1200?C. According to the results there was a high iron oxide on black quartzite, being their use in porcelain stoneware discarded by ethic and structural question, because the material fused at 1250?C. All quartzite formulations had low water absorption when synthesized at 1200?C, getting 0.1% to 0.36% without having gone through the atomization process. Besides, flexural strain tests overcame 27 MPa reaching the acceptance limits of the European Directive EN 100, at 1200?C synthesizing. Thus, the use of quartzite residues in ceramic masses poses as great potential for the production of porcelain stoneware.
26

Estudo do aproveitamento de res?duos PAE no desenvolvimento de materiais cer?micos

Borges, Aldo Nonato 29 August 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-06-09T23:48:15Z No. of bitstreams: 1 AldoNonatoBorges_TESE.pdf: 15608480 bytes, checksum: 60c4bf5bb7ac9afa99560b220ddce23d (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-10T20:43:53Z (GMT) No. of bitstreams: 1 AldoNonatoBorges_TESE.pdf: 15608480 bytes, checksum: 60c4bf5bb7ac9afa99560b220ddce23d (MD5) / Made available in DSpace on 2016-06-10T20:43:53Z (GMT). No. of bitstreams: 1 AldoNonatoBorges_TESE.pdf: 15608480 bytes, checksum: 60c4bf5bb7ac9afa99560b220ddce23d (MD5) Previous issue date: 2014-08-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Neste trabalho ? apresentado um novo material cer?mico obtido por meio da incorpora??o de res?duos s?lidos, provenientes do setor sider?rgico e conhecido como p? de despoeiramento ? res?duo PAE ? em formula??es cer?micas ? base de argila, feldspatos s?dicos e pot?ssicos, caulim e talco. Formula??es cer?micas foram preparadas com teores de res?duos de 0% (massa b?sica ? MB), 2%, 4% e 8%, submetidas ? queima nas temperaturas de 1000?C, 1050?C, 1100?C e 1150?C, durante os per?odos de 15 min. e 120 min. As propriedades f?sico-qu?micas e mec?nicas dessas formula??es cer?micas foram determinadas em fun??o da temperatura de queima, tempo de perman?ncia em forno e do percentual de res?duos. J? as propriedades f?sico-qu?micas e mec?nicas dos materiais sinterizados foram avaliadas atrav?s de t?cnicas de an?lise qu?mica (Fluoresc?ncia de Raios-X ? FRX), distribui??o granulom?trica, superf?cie espec?fica, massa espec?fica aparente, an?lise estrutural por difra??o de raios-X (DRX) e caracteriza??o de superf?cie por microscopia eletr?nica de varredura (MEV). A resposta magn?tica, as caracter?sticas e o padr?o magn?tico das ferritas foram analisados nas condi??es de ensaio das amostras, constatando-se que a susceptibilidade magn?tica de satura??o independe da temperatura de sinteriza??o do material, estando relacionada ? sua estrutura cristalina. A partir da an?lise dos resultados, concluiu-se que o material cer?mico com melhores propriedades f?sicas e mec?nicas ? obtido quando ? adicionado 8% do res?duo PAE ? formula??o padr?o, sob o tempo de queima de 15 minutos e temperatura de 1150?C. / This work presents a new ceramic material obtained through the incorporation of solid waste from the steel industry and known as dedusting powder PAE - in ceramic formulations based on clay, potassium and sodium feldspars, kaolin and talc. Formulations were prepared with ceramic residue levels of 0% (basic mass - MB), 2%, 4% and 8%, subjected to firing at temperatures of 1000 ? C, 1050?C, 1100?C and 1150?C for periods of 15 min. and 120 min. The physicchemical and mechanical properties of these ceramic formulations were determined based on the firing temperature, residence time in the oven and the percentage of waste. Since the physicochemical and mechanical properties of the sintered materials were evaluated by chemical analysis techniques (fluorescence X-rays - FRX), particle size distribution, specific surface area, apparent density, structural analysis by diffraction of X-rays (DRX) and characterization of surface by scanning electron microscopy (SEM). The magnetic response characteristics and the pattern of magnetic ferrites of the samples were analyzed in the assay conditions, having noticed that the saturation magnetic susceptibility depend on the sintering temperature of the material and it is associated with its crystal structure. From the analysis results, it was concluded that the ceramic material with better physical and mechanical properties is obtained when the 8% from PAE residue is added to standard formulation under the burn time of 15 minutes and temperature of 1150?C.
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Estudo da incorpora??o de cinza e chamote gerado pela cer?mica vermelha ao pr?prio processo industrial / Study of the incorporation of ash and chamote generated by red ceramic to own industrial process

Almeida, Melise Carina Duarte de 27 November 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-22T15:34:02Z No. of bitstreams: 1 MeliseCarinaDuarteDeAlmeida_DISSERT.pdf: 4982538 bytes, checksum: 7e42f255bc7d008f276d0c784126c575 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-27T22:49:26Z (GMT) No. of bitstreams: 1 MeliseCarinaDuarteDeAlmeida_DISSERT.pdf: 4982538 bytes, checksum: 7e42f255bc7d008f276d0c784126c575 (MD5) / Made available in DSpace on 2016-07-27T22:49:26Z (GMT). No. of bitstreams: 1 MeliseCarinaDuarteDeAlmeida_DISSERT.pdf: 4982538 bytes, checksum: 7e42f255bc7d008f276d0c784126c575 (MD5) Previous issue date: 2015-11-27 / A ind?stria ceramista gera res?duos em v?rias etapas de seu processo, por produtos defeituosos, res?duos da queima de combust?veis s?lidos, entre outros. Esses res?duos s?o despejados em aterros, lix?es ou diretamente nas vias, o que causa um impacto ambiental negativo. Este trabalho apresenta um estudo para incorporar os res?duos de cinza de lenha da algaroba e chamote (pe?as de refugo de cer?micas j? sinterizadas), nas massas cer?micas para confec??o de Blocos de Veda??o. Os procedimentos metodol?gicos consistem na caracteriza??o qu?mica e mineral?gica dos res?duos e das mat?rias-primas, e caracteriza??o f?sico-mec?nica das formula??es das misturas com argila, silte e res?duos. Foram produzidos corpos de prova por prensagem, com varia??es de composi??es no intervalo de 0%, 5%, 10% e 15% em massa de res?duo. A sinteriza??o foi realizada em forno tipo mufla, com patamares nas temperaturas de 850 ?C, 900 ?C, 950 ?C, 1000 ?C e 1050 ?C. As propriedades f?sico-mec?nicas avaliadas foram: Absor??o de ?gua, Retra??o Linear de Queima, Porosidade Aparente, Massa Espec?fica Aparente e Resist?ncia Mec?nica ? Flex?o. Foi realizada an?lise por Microscopia Eletr?nica de Varredura nas superf?cies de fratura dos corpos de prova. Foram avaliadas as propriedades de Retra??o Linear de Secagem e Queima, Absor??o de ?gua e Resist?ncia Mec?nica ? Compress?o dos Blocos de Veda??o com 5% de res?duo de cinza da lenha de algaroba, sinterizados no patamar de temperatura de 900 ?C. Como resultados principais, concluiu-se sobre a viabilidade em se utilizar os res?duos de cinza da lenha de algaroba para conferir propriedades refrat?rias ao produto cer?mico. J? o res?duo de chamote, por ser derivado do pr?prio produto cer?mico, n?o interferiu nas propriedades finais. Os estudos comprovaram que a incorpora??o desses res?duos seria uma alternativa tecnol?gica para reduzir o impacto ambiental causado pelo setor industrial. / The ceramics industry generates waste at various stages of that process, defective products, waste from burning solid fuels, among others. This waste is dumped in landfills, garbage dumps or directly on roads, which has a negative environmental impact. This paper presents a study to incorporate the waste of algaroba wood and chamote (scrap pieces of ceramic already sintered), in to the ceramic material for making sealing blocks. The methodological procedures consist in the characterization of chemical and mineralogical residues, raw materials, and physical-mechanical of the formulations of mixes with clay, silt and waste. By pressing test pieces were produced using a pressure of 200 kgf/cm?, varying compositions in the range of 0%, 5%, 10% and 15% by weight of residue. The sintering was performed in a muffle furnace, with the temperature levels of 850 ? C, 900 ? C, 950 ? C, 1000 ? C and 1050 ? C. The evaluated physical and mechanical properties were: Water Absorption, Linear Shrinkage Burning, Apparent Porosity, Apparent Density and Mechanical Resistance to Flexion. Analysis was carried out by Scanning Electron Microscopy on fracture surfaces of the specimens. Evaluation of linear shrinkage property drying and firing , water absorption and mechanical resistance to compression of the sealing blocks 5% wood ash residue, sintered at 900 ?C hold temperature in the laboratory the products manufactured on an industrial scale. The main results, it was found on the viability of using the residues of algaroba wood and to confer refractory properties of the ceramic product. The main results, it was concluded feasibility of using the ash residues algaroba wood to impart refractory properties to the ceramic product and the residue of chamote, being derived from the own ceramic product not interfere with the properties, when used in a percentage of up to 5%.Since the residue of chamote being derived from the ceramic product itself had no effect on the properties. Studies in the laboratory have shown that the incorporation of up to 5% of these residues may be adopted as an alternative technology to reduce the environmental impact caused by the industrial sector, without compromising the final properties of the material, since the results on an industrial scale showed absorption values 11.66 and 11.74 of water and waste products respectively, within the parameters of NBR - 15,270, since the mechanical strength was 1.25 MPa and 0.94 MPa respectively for products with and without residue, lower than the minimum required by the technical standard that is 1.5 MPa.
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Gerenciamento de res?duos s?lidos recicl?veis: estudo de caso das cooperativas do munic?pio de Natal/RN

Bispo, Cristina de Souza 20 September 2013 (has links)
Made available in DSpace on 2014-12-17T14:53:16Z (GMT). No. of bitstreams: 1 CristinaSB_DISSERT.pdf: 8141257 bytes, checksum: 871cd95d3a846703a2c9ec0b91319298 (MD5) Previous issue date: 2013-09-20 / This dissertation conducted in the years 2011 and 2012, an analysis of cooperatives waste pickers in the city of Natal, Rio Grande do Norte, aiming to identify improvements to be implemented to assist the management of waste from the municipality as well as to improve the living conditions of the workers who perform the selective collection, the environmental perspective. This analysis was performed by means of an investigation of the reality in which they live cooperatives and their local representation, using also the law. The research is characterized as a case study of an applied nature, documentary, consultations with the institutions related to the issue of solid waste in the national and local levels; exploratory and descriptive, the main methodological tools technical visits and structured interviews. From these methods was possible to obtain data regarding the organization of cooperatives, environmental perception of the collector of recyclable materials, among other issues. For the analysis of data matrices were used to include comments and method GUT, from which it was possible to identify numerous difficulties faced by recycling cooperatives, and develop proposals for possible improvements in various aspects of their operation, such as infrastructure and production process , which can improve both the waste management and the quality of life of workers involved in the selective collection system city / A presente disserta??o realizou, nos anos de 2011 e 2012, uma an?lise das cooperativas de catadores de materiais recicl?veis da cidade de Natal, Rio Grande do Norte, tendo como objetivo identificar melhorias a serem implementadas para auxiliar o gerenciamento dos res?duos do munic?pio, bem como para a melhoria das condi??es de vida dos trabalhadores que realizam a coleta seletiva, na perspectiva socioambiental. Tal an?lise realizou-se por meio de uma investiga??o da realidade na qual vivem as cooperativas e de sua representatividade local, utilizando-se tamb?m da legisla??o vigente. A pesquisa caracteriza-se como um estudo de caso de natureza aplicada; documental, com consultas ?s institui??es relacionadas ? quest?o dos res?duos s?lidos nos cen?rio nacional e local; explorat?ria e descritiva, tendo como principais instrumentos metodol?gicos visitas t?cnicas e entrevistas semiestruturadas. A partir dos referidos m?todos foi poss?vel obter dados referentes ? organiza??o das cooperativas, percep??o ambiental do catador de materiais recicl?veis, entre outras quest?es. Para a an?lise dos dados foram utilizadas matrizes de inclus?o de coment?rios e o m?todo GUT, a partir dos quais foi poss?vel identificar in?meras dificuldades enfrentadas pelas cooperativas de catadores, al?m de elaborar propostas de poss?veis melhorias em diversos aspectos de seu funcionamento, como infraestrutura e processo produtivo, as quais possam aprimorar tanto a gest?o dos res?duos, quanto a qualidade de vida dos trabalhadores envolvidos no sistema de coleta seletiva municipal
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Avalia??o mec?nica e microestrutural de comp?sitos de poli?ster com adi??o de cargas minerais e res?duos industriais

Santos, Eylisson Andr? dos 26 July 2007 (has links)
Made available in DSpace on 2014-12-17T14:58:25Z (GMT). No. of bitstreams: 1 EylissonAS.pdf: 1489335 bytes, checksum: 8fcffdaaafca0f8691545bd2bc5dd5fc (MD5) Previous issue date: 2007-07-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / With the current growth in consumption of industrialized products and the resulting increase in garbage production, their adequate disposal has become one of the greatest challenges of modern society. The use of industrial solid residues as fillers in composite materials is an idea that emerges aiming at investigating alternatives for reusing these residues, and, at the same time, developing materials with superior properties. In this work, the influence of the addition of sand, diatomite, and industrial residues of polyester and EVA (ethylene vinyl acetate), on the mechanical properties of polymer matrix composites, was studied. The main objective was to evaluate the mechanical properties of the materials with the addition of recycled residue fillers, and compare to those of the pure polyester resin. Composite specimens were fabricated and tested for the evaluation of the flexural properties and Charpy impact resistance. After the mechanical tests, the fracture surface of the specimens was analyzed by scanning electron microscopy (SEM). The results indicate that some of the composites with fillers presented greater Young s modulus than the pure resin; in particular composites made with sand and diatomite, where the increase in modulus was about 168 %. The composites with polyester and EVA presented Young s modulus lower than the resin. Both strength and maximum strain were reduced when fillers were added. The impact resistance was reduced in all composites with fillers when compared to the pure resin, with the exception of the composites with EVA, where an increase of about 6 % was observed. Based on the mechanical tests, microscopy analyses and the compatibility of fillers with the polyester resin, the use of industrial solid residues in composites may be viable, considering that for each type of filler there will be a specific application / Com o crescimento acelerado do consumo de produtos industrializados, principalmente de produtos descart?veis, o aumento excessivo de lixo e sua disposi??o em lugares inadequados tornaramse um dos grandes problemas da sociedade moderna. A utiliza??o de res?duos s?lidos industriais como carga em comp?sitos ? uma id?ia que surge com o intuito de buscar alternativas adequadas para o reaproveitamento desses res?duos, visando tamb?m o desenvolvimento de materiais com propriedades superiores ?quelas dos materiais convencionais. Neste trabalho, estudouse a influ?ncia da adi??o de res?duos industriais de poli?ster e EVA (Etileno Acetato de Vinila), al?m de cargas de areia e diatomita, nas propriedades mec?nicas de comp?sitos de matriz poli?ster. O principal objetivo foi avaliar o comportamento mec?nico desses materiais com a adi??o de cargas de res?duo industrial, comparandoos com as propriedades da resina pura. Corposdeprova foram confeccionados e as propriedades mec?nicas dos comp?sitos obtidos foram analisadas, atrav?s de testes de flex?o e de impacto. Ap?s os ensaios mec?nicos, a superf?cie de fratura dos corposdeprova foi analisada por microscopia eletr?nica de varredura (MEV). Os resultados dos ensaios de flex?o mostraram que alguns comp?sitos apresentaram maior m?dulo, quando comparados com os resultados da resina pura; com destaque para os confeccionados com areia e diatomita, em que o aumento do m?dulo chegou a 168 %. Os comp?sitos confeccionados com adi??o de poli?ster e de EVA apresentaram m?dulo mais baixo que o da resina pura. Tanto o limite de resist?ncia quanto ? deforma??o m?xima, apresentaram redu??o nos seus valores, quando da adi??o de cargas. A resist?ncia ao impacto, em rela??o ? resina pura, foi reduzida em todos os comp?sitos com adi??o de cargas, exceto nos comp?sitos com a adi??o de EVA, onde houve um aumento de aproximadamente 6 %. Com base nos ensaios mec?nicos realizados, nas an?lises microsc?picas e na compatibilidade das cargas com a resina poli?ster, a utiliza??o das cargas de res?duos s?lidos industriais em comp?sitos mostrouse vi?vel, considerando que para cada tipo de carga haver? uma aplica??o espec?fica
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Obten??o e caracteriza??o de um comp?sito de matriz cer?mica com cargas de res?duos de eps e raspa de pneu para constru??o de casas populares

Lima, Fl?vio Anselmo Silva de 17 June 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-27T12:30:35Z No. of bitstreams: 1 FlavioAnselmoSilvaDeLima_TESE.pdf: 5034235 bytes, checksum: 5889588654d8773f78e4f287028fd71b (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-30T14:46:40Z (GMT) No. of bitstreams: 1 FlavioAnselmoSilvaDeLima_TESE.pdf: 5034235 bytes, checksum: 5889588654d8773f78e4f287028fd71b (MD5) / Made available in DSpace on 2017-01-30T14:46:40Z (GMT). No. of bitstreams: 1 FlavioAnselmoSilvaDeLima_TESE.pdf: 5034235 bytes, checksum: 5889588654d8773f78e4f287028fd71b (MD5) Previous issue date: 2016-06-17 / A utiliza??o de materiais comp?sitos na constru??o civil tem sido linha de pesquisa nos maiores centros de pesquisas do Brasil e do mundo. Um dos fatores que justifica essa busca ? o d?ficit habitacional dos pa?ses subdesenvolvidos e em desenvolvimento. No Brasil esse d?ficit alcan?a mais de 5,4 milh?es de moradias, em torno de 12% dos domic?lios do pa?s. Esse trabalho apresenta um comp?sito que foi obtido a partir de materiais convencionalmente utilizados, cimento, gesso e areia; res?duos industriais gerados, o EPS, raspa de pneu e ?gua O ineditismo do trabalho est? no estudo de caracteriza??o combinada, t?rmica e mec?nica do comp?sito obtido. Estudou-se tamb?m a influ?ncia de tr?s tipos de recheio, colocados nos blocos (79cm X 28cm X 10cm) fabricados com o material comp?sito destinado ? edifica??o de resid?ncias populares. Foram estudadas quatro formula??es para o estudo combinado, determinando-se a mais vi?vel. Ser?o apresentados os processos de fabrica??o e montagem dos blocos produzidos para a constru??o de resid?ncias populares. Determinou-se o tipo de recheio, placas de EPS recicladas, latas de cervejas e refrigerantes reutilizadas e garrafas PETs de ?gua mineral de 500ml. Foi tamb?m realizado um estudo preliminar de conforto t?rmico com blocos fabricados com os recheios utilizados em um espa?o edificado em uma Escola P?blica de Natal, denominado Espa?o Ci?ncia. A resist?ncia mec?nica do comp?sito para todas as formula??es est? classificada como alvenaria de veda??o, abaixo 3,0 MPa. A resist?ncia t?rmica dos blocos foi comprovada pela diferen?a de temperatura m?xima entre as paredes interna e externa do c?modo edificado em torno 8,0 ?C e condutividade t?rmica praticamente igual a do tijolo de oito furos e inferior a dos blocos de concreto e tijolos maci?os, o que demonstrou a viabilidade de utiliza??o dos blocos produzidos para o fim proposto. Outras caracter?sticas importantes dos blocos produzidos ? o seu bom acabamento, n?o necessitando de reboco, o que diminui o custo de m?o de obra em um processo construtivo e o seu r?pido tempo de cura, pela utiliza??o do gesso. A formula??o mais vi?vel para o estudo combinado, t?rmico e mec?nico foi 1,0 C + 1,0 G + 1,0 EPS + 1,0 RP. Para a fabrica??o de blocos essa formula??o seria a mais vi?vel com e com recheio de placas de EPS. / The use of composite materials in construction has been a line of research quite investigated in Brazil and worldwide. One of the factors justifying this search is the housing deficit of underdeveloped and developing countries. In Brazil this deficit reaches more than 5.4 million homes, approximately 12% of all country households according to IBGE 2012. To contribute to the reduction of this housing deficit presents the study of four formulations of a composite that was obtained from materials conventionally used in construction (cement, gypsum and sand), together with residue of own construction (Styrofoam) tire scrapings and water in order to manufacture blocks with dimensions (79 cm x 28 cm x 10 cm) for building affordable housing using different types of fillings inside the block, such as cans, bottles of mineral water and EPS boards. Was built a room using blocks with the fillings mentioned above in a Public School Christmas and conducted temperature checks on these blocks. They were also performed mechanical, thermal and physical testing to characterize the best formulation. The mechanical strength of the composite for all formulations are classified as sealing masonry below 3.0 MPa. The thermal resistance of the blocks was confirmed by the maximum temperature difference between the inner and outer walls of the room built around 8.0 ? C and thermal conductivity nearly equal to the eight holes wall and bottom of the concrete blocks and solid bricks, which demonstrated the feasibility of using blocks made for the intended purpose.

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