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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.
71

An?lise da adi??o de res?duo oriundo do tratamento de esgotos em massa cer?mica utilizada para fabrica??o de telhas

Lima, Andressa Dantas de 30 April 2009 (has links)
Made available in DSpace on 2014-12-17T15:03:20Z (GMT). No. of bitstreams: 1 AndressaDL.pdf: 2033503 bytes, checksum: bb95c834e7758cc771aaa11779a97e45 (MD5) Previous issue date: 2009-04-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Sludge of Wastewater Treatment Plants (WTPs) disposal is a problem for any municipality, for this reason the amount of sludge production is now a key issue in selecting treatment methods. It is necessary to investigate new applications for this waste type, due to the restrictions imposed by the environmental organs. The raw materials used in the Red Ceramic, are generally very heterogeneous, for this reason, such materials can tolerate the presence of different types of wastes. In Rio Grande do Norte, the roof tiles production corresponds to 60,61% from the total of ceramic units produced. Due to the importance of the ceramic industry of roof tiles for the state, allied to the environmental problem of the sludge disposal, this work had for objective to verify the possibility of the incorporation of sewage sludge in ceramic body used for production of roof tiles. In the research, sludge originating from drying beds of WTP of the Central Campus from UFRN and clays originating from a ceramic industry from Goianinha/RN were used. The raw materials were characterized by techniques of: analysis of particles distribution by diffraction to laser; real density; consistence limits; chemical analysis by X-ray fluorescence; mineralogical analysis by X-ray diffraction; organic matter; and solids content. Five batches of roof tiles were manufactured in the approximate dosages of 2%, 4%, 6%, 8% and 10%. To evaluate the properties of each final product, tests of water absorption, impermeability, bending strength, leachability and solubility were accomplished. The roof tiles manufactured with sludge presented characteristics similar to the roof tiles without sludge in relation to the environmental risk. The results showed that it is possible to use approximately up to 4% of sludge in ceramic bodies for production of roof tiles. However, it is observed that the high amount of organic matter (71%) present in the sludge is shown as factor that limits the sludge incorporation in ceramic bodies, worsening the quality of the roof tiles. It is necessary the use of mixtures of different raw materials under point of view of the granulometry and of the other chemical and mineralogical properties for the obtaining of a satisfactory mass to the production of ceramic roof tiles / A disposi??o de lodo de Esta??es de Tratamento de Esgotos (ETEs) ? um problema para qualquer municipalidade, por isso a quantidade de lodo produzido ? hoje um assunto fundamental na sele??o de m?todos de tratamento. Faz-se necess?rio investigar novas aplica??es para esse tipo de res?duo, face ?s restri??es impostas pelos ?rg?os ambientais. As mat?rias-primas utilizadas na Cer?mica Vermelha, em geral, s?o muito heterog?neas, por isso podem tolerar a presen?a de tipos diferentes de res?duos. No Rio Grande do Norte, a produ??o de telhas corresponde a 60,61% do total de pe?as cer?micas produzidas. Dada a import?ncia da ind?stria cer?mica de telhas para o estado, aliada ? problem?tica ambiental da disposi??o de lodo, este trabalho teve por objetivo verificar a possibilidade da incorpora??o de lodo de esgotos em massa cer?mica utilizada para fabrica??o de telhas. Foram utilizados na pesquisa lodo proveniente dos leitos de secagem da ETE do Campus Central da UFRN e argilas provenientes de uma ind?stria cer?mica de Goianinha/RN. As mat?rias-primas foram caracterizadas por t?cnicas de: an?lise de distribui??o de part?culas por difra??o ? laser; densidade real; limites de consist?ncia; an?lise qu?mica por fluoresc?ncia de raios X; an?lise mineral?gica por difra??o de raios X; mat?ria org?nica; e teor de s?lidos. Foram fabricados cinco lotes de telhas nas dosagens aproximadas de 2%, 4%, 6%, 8% e 10%. Para avaliar as propriedades de cada produto final, foram realizados ensaios de absor??o de ?gua, impermeabilidade, carga de ruptura ? flex?o, lixivia??o e solubiliza??o. As telhas fabricadas com lodo apresentaram caracter?sticas semelhantes ?s telhas sem lodo no que diz respeito ao risco ambiental. Os resultados mostraram que ? poss?vel utilizar aproximadamente at? 4% de lodo em massas cer?micas para fabrica??o de telhas. Contudo, observa-se que a elevada quantidade de mat?ria org?nica (71%) presente no lodo mostra-se como fator limitante na incorpora??o de lodo em massas cer?micas, comprometendo a qualidade das telhas. Destaca-se a necessidade de utiliza??o de misturas de diferentes mat?rias-primas do ponto de vista granulom?trico e das outras propriedades qu?micas e mineral?gicas para a obten??o de uma massa satisfat?ria ? produ??o de telhas cer?micas
72

A percep??o da desertifica??o e da mudan?a na paisagem no munic?pio de Parelhas/RN / The perception of desertification and change in the landscape in the city of Parelhas/RN

Ara?jo, Jane Azevedo de 29 August 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-09T23:07:11Z No. of bitstreams: 1 JaneAzevedoDeAraujo_TESE.pdf: 3701615 bytes, checksum: b82d98bec5dae84828bd4834307f582f (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-14T00:29:45Z (GMT) No. of bitstreams: 1 JaneAzevedoDeAraujo_TESE.pdf: 3701615 bytes, checksum: b82d98bec5dae84828bd4834307f582f (MD5) / Made available in DSpace on 2017-03-14T00:29:45Z (GMT). No. of bitstreams: 1 JaneAzevedoDeAraujo_TESE.pdf: 3701615 bytes, checksum: b82d98bec5dae84828bd4834307f582f (MD5) Previous issue date: 2016-08-29 / A inter-rela??o sociedade/natureza ocasiona mudan?as ao meio ambiente. Essas mudan?as ocorrem por meio do trabalho do homem, que utiliza os recursos naturais, em prol do seu desenvolvimento. Por essa raz?o, a sociedade, tem a capacidade construir e reconstruir os lugares onde vive, deixando registradas na paisagem as transforma??es ocorridas. A paisagem ? modificada ao longo dos anos, e o homem ? fundamental para esse processo, pois al?m de ser o autor das mudan?as, consegue descrev?-las atrav?s da percep??o que tem de um mesmo lugar, seja referente ao passado ou ao presente. O objetivo geral dessa pesquisa foi compreender a percep??o dos moradores do munic?pio de Parelhas/RN em rela??o ? desertifica??o e ? mudan?a na paisagem. A pesquisa foi realizada na ?rea urbana e em tr?s comunidades rurais ? Juazeiro, Cachoeira e Cobra. Foram aplicados 26 formul?rios com os empres?rios, gerentes e/ou respons?veis pelas cer?micas e 176 com parte da popula??o urbana (102) e nas comunidades rurais, Juazeiro, Cachoeira e Cobra (74). Os m?todos estat?sticos utilizados para a an?lise dos dados foram Qui-quadrado de Person (??), o teste de Fisher e a An?lise de Correspond?ncia. Para a descri??o dos dados sociais dos respondentes, elaboraram-se tabelas de conting?ncia e quadros. Os resultados mostraram que a ind?stria de cer?mica existe no munic?pio desde meados da d?cada de 1980. Os produtos fabricados pelas ind?strias s?o telhas, tijolos, lajotas, casquilhos, blocos e manilhas, sendo a telha o artefato mais produzido. A principal fonte energ?tica utilizada pelas cer?micas ? a lenha, e 73% ainda fazem uso exclusivamente da lenha. A retirada sem t?cnica da vegeta??o deixa ?reas desnudas e solos expostos a eros?o, contribuindo para aumentar a susceptibilidade ao fen?meno da desertifica??o no munic?pio. A an?lise comparativa da percep??o dos moradores da zona rural e urbana sobre desertifica??o mostrou que a maioria dos respondentes j? ouviu falar a respeito do tema; no entanto, as pessoas que residem na cidade (79,41%) ouviram falar mais do que as que moram na zona rural (52,70%). Dentre as alternativas sobre os causadores do processo de desertifica??o no munic?pio, a atividade ceramista foi a mais indicada. Acredita-se que essa escolha esteja relacionada com o alto consumo dos recursos naturais locais (lenha, argila e ?gua) que a atividade demanda na fabrica??o de seus produtos. Os resultados da percep??o sobre mudan?a na paisagem dos moradores das comunidades rurais Juazeiro, Cachoeira e Cobra, mostraram que a maioria percebe mudan?a da paisagem local. Do mesmo modo, mudan?as na vegeta??o, no solo e nas pastagens foram relatadas. Aqueles na faixa et?ria de 25 a 59 anos foram os que mais perceberam mudan?as na paisagem. Os respondestes que estudaram at? o Ensino Fundamental foram os que menos perceberam a mudan?a na paisagem, enquanto aqueles com ensino m?dio completo/incompleto e ensino superior completo/incompleto foram os que mais perceberam mudan?as na paisagem. Esses resultados podem servir de subs?dio ? defini??o de pol?ticas p?blicas a serem implementadas no semi?rido do Estado do Rio Grande do Norte, sob a ?tica da conserva??o dos recursos naturais, em uma ?rea suscet?vel ao fen?meno da desertifica??o. Sugest?es de a??es s?o apresentadas. / The interrelation society/nature causes changes to the environment. These changes occur through the work of man, which uses natural resources, to support his development. For that reason, the society has the ability to build and rebuild the places where lives, leaving registered on the landscape the changes occurred. The landscape is modified over the years, and the man is critical to this process because, in addition to being the author of the alterations can describe them through the perception from a same place, either from the past or from the present. The general objective of this research was to understand the perception of the residents of the city of Parelhas/RN in relation to desertification and to the change in the landscape. The survey was conducted in the urban area and in three rural communities-Juazeiro, Cachoeira and Cobra. Twenty-six forms were applied with the entrepreneurs, managers and/or responsible for ceramics and 176 with part of the urban population (102) and in rural communities Juazeiro, Cachoeira and Cobra (74). Statistical methods used for data analysis were Person Chi-square (??), the Fisher test and correlation analysis. To describe the social data of the respondents, contingency tables and data frames were prepared. The results showed that the ceramic industry exists in the city since the mid-1980. The products manufactured by the industries are roofing tiles, bricks, tiles, bushings, blocks and shackles, being tile the most produced artifact. The main energy source used for ceramics is the firewood, and 73% still make exclusively use of wood. The withdrawal of vegetation without any technique leaves bare areas and exposed soils to erosion, contributing to increase the susceptibility to the phenomenon of desertification in the municipality. The comparative analysis of the perception of the residents of the rural and urban area on desertification, showed that most respondents have heard on the subject; however, the people living in the city (79,41%) have heard more than those who live in the rural area (52,70%). Among the alternatives on the causes of desertification in the municipality, the ceramic industry was the most indicated activity. It is believed that this choice is related to the high consumption of the local natural resources (wood, clay and water) that this activity demands in manufacturing their products. The results of the perception of change in the landscape of the inhabitants of the rural communities Juazeiro, Cachoeira and Cobra, showed that most of them noticed changes in the local landscape. Likewise, changes in vegetation, soil and grassland have been reported. Those aged 25 to 59 years were the ones who most noticed changes in the landscape. The ones who studied until elementary school were the ones that least realized the modifications in landscape, while those with complete/incomplete secondary education and complete/incomplete higher education were the ones that most noticed changes in the landscape. These results can serve as a subsidy to the definition of public policies to be implemented in semi-arid of Rio Grande do Norte State, from the perspective of conservation of natural resources, in an area susceptible to the phenomenon of desertification. Suggestions of actions are presented.
73

Avalia??o da potencialidade dos res?duos de gesso de revestimento incorporados em formula??es de massas cer?micas

Silva, Jaquel?gia Brito da 08 October 2008 (has links)
Made available in DSpace on 2014-12-17T14:06:58Z (GMT). No. of bitstreams: 1 JaqueligiaBS_Capa_ate_referencias.pdf: 4148676 bytes, checksum: c08764d974461ebcf86494a06a296078 (MD5) Previous issue date: 2008-10-08 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In building, during the implementation process of major or even minor works, there is a considerable waste of plaster in the steps of coating, making it is a negative factor because of the loss of these processes constructive remains incorporated into buildings, as component, whose final dimensions are higher than those projected. Another negative factor is the disposal of waste gypsum in inappropriate places, thus contributing to the degradation of environmental quality, due to the leaching of this waste and may trigger the formation of sulfuric acid. Therefore, based on this picture, processing and reuse of waste coating, combined with the ceramics industry, which is a strong potential in the reuse of certain types of waste, promote mutual benefits. Thus the overall objective of this work is to conduct a search with scientific and technological aspects, to determine the effect of the incorporation of the residue of plaster for coating, from the building, the formulation of bodies for red ceramic. The residue of plaster coating was collected and characterized. They were also selected raw materials of two ceramic poles of the state of Rio Grande do Norte and formulations have been made with the intention of obtaining those with the best physical and mechanical properties, the residue was added the percentage of 5%, 10%, 15%, 20%, 25% and 30%, in the best formulation of ceramic industry 1 and, according the properties analyses, 5%, 10% and 15% as the best results of ceramic industry 2. The samples were sintered at temperatures of 850 ?C, 950 ?C and 1050 ?C, the heating rate of 5 ?C / min with isotherm of two hours. They were submitted to testing technology, such as lineal shrinkage, water absorption, apparent porosity, apparent density and bending resistence. The residue incorporation best results in the formulations of mass in red ceramic, were observed between the temperatures of 850 ?C and 950 ?C, in those formulations that have illite clays and medium plastic in their composition, in the range of 0% to 15% residue incorporated / Na constru??o civil, durante o processo de execu??o de grandes ou at? mesmo pequenas obras, h? um desperd?cio consider?vel de gesso nas etapas de revestimento, tornando-se este um fator negativo, pois parte das perdas destes processos construtivos permanece incorporada nas constru??es, na forma de componentes, cujas dimens?es finais s?o superiores ?quelas projetadas. Outro fator negativo ? a disposi??o dos res?duos de gesso em locais inadequados, contribuindo assim para a degrada??o da qualidade ambiental, devido ao processo de lixivia??o deste res?duo, podendo desencadear na forma??o de ?cido sulf?rico. Baseado neste panorama, a transforma??o e o reaproveitamento dos res?duos de revestimento, aliada ? ind?stria da cer?mica, que ? um forte potencial no reaproveitamento de alguns tipos de res?duos, promoveria benef?cios m?tuos. O objetivo geral deste trabalho foi de realizar uma pesquisa com aspectos cient?ficos e tecnol?gicos, para verificar o efeito da incorpora??o do res?duo de gesso para revestimento, proveniente da constru??o civil, na formula??o de massas para cer?mica vermelha. As mat?rias-primas foram coletadas de dois p?los cer?micos do Estado do Rio Grande do Norte e formuladas com o intuito de obter aquelas com as melhores propriedades f?sicas e mec?nica, tendo sido incorporados os percentuais 5%, 10%, 15%, 20%, 25% e 30% de res?duo, na melhor formula??o da ind?stria cer?mica 1 e, de acordo com a an?lise dos seus resultados, de 5%, 10% e 15% na melhor formula??o da ind?stria cer?mica 2. As amostras foram sinterizadas ?s temperaturas de 850 ?C, 950 ?C e 1050 ?C, ? taxa de aquecimento de 5 ?C/min com isoterma de duas horas e submetidas a ensaios tecnol?gicos, como retra??o linear de queima, absor??o de ?gua, porosidade aparente, massa espec?fica aparente e resist?ncia mec?nica ? flex?o. Os melhores resultados de incorpora??o do res?duo nas formula??es de massa de cer?mica vermelha foram observados na faixa de temperatura de 850 ?C a 950 ?C, naquelas que possuem argilas il?ticas e medianamente pl?sticas em sua composi??o, na faixa de 0% a 15% de res?duo incorporado
74

S?ntese e impregna??o de peneiras moleculares Fe MCM-41 derivada de s?lica da casca do arroz

Miranda, Auristela Carla de 28 November 2011 (has links)
Made available in DSpace on 2014-12-17T14:07:00Z (GMT). No. of bitstreams: 1 AuristelaCM_DISSERT.pdf: 1278248 bytes, checksum: cbdcf9cab5a2fc14113da4b21bc60b64 (MD5) Previous issue date: 2011-11-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The mesoporous molecular sieves of the MCM-41 and FeMCM-41 type are considered promissory as support for metals used as catalysts in oil-based materials refine processes and as adsorbents for environmental protection proposes. In this work MCM-41 and FeMCM41 were synthesized using rice husk ash - RHA as alternative to the conventional silica source. Hydrothermal synthesis was the method chosen to prepare the materials. Pre-defined synthesis parameters were 100?C for 168 hours, later the precursor was calcinated at 550?C for 2 hours under nitrogen and air flow. The sieves containing different proportions of iron were produced by two routes: introduction of iron salt direct synthesis; and a modification post synthesis consisting in iron salt 1 % and 5% impregnation in the material followed by thermal decomposition. The molecular sieves were characterized by X ray diffraction XRD, Fourier transform infrared spectroscopy FT-IR, X ray fluorescence spectroscopy XFR, scanning electronic microscopy SEM, specific surface area using the BET method, Termogravimetry TG. The kinetic model of Flynn Wall was used with the aim of determining the apparent activation energy of the surfactant remove (CTMABr) in the MCM- 41 porous. The analysis made possible the morphology characterization, identifying the presence of hexagonal structure typical for mesoporous materials, as well as observation of the MCM41 and iron of characteristic bands. / As peneiras moleculares mesoporosas do tipo MCM-41 e FeMCM-41, s?o consideradas promissoras como suporte para metais, usadas como catalisadores em processos de refino de materiais a base de petr?leo e como adsorventes com o prop?sito de prote??o ambiental. Neste trabalho MCM-41 e FeMCM-41 foram sintetizadas utilizando a cinza da casca de arroz CCA, como alternativa para a fonte de s?lica. O m?todo escolhido foi a s?ntese hidrotermal para o preparo dos materiais, a temperatura de 100 ?C por 168 horas em estufa, posteriormente foi calcinado a 550 ?C por 2 horas sob fluxo de nitrog?nio e ar. As peneiras moleculares contendo diferentes propor??es de ferro foram produzidas por duas rotas: introdu??o do sal de ferro no gel de s?ntese e impregna??o de 1% e 5% de ferro no MCM-41 sintetizado. As peneiras moleculares foram caracterizadas por difra??o de raios X DRX, espectroscopia no infravermelho por transformada de Fourier (Fourier transform infrared spectroscopy FT-IR), espectroscopia de fluoresc?ncia de raios X FRX, microscopia eletr?nica de varredura MEV, ?rea superficial espec?fica atrav?s do m?todo BET e Termogravimetria TG. O modelo cin?tico de Flynn Wall foi utilizado com o objetivo de determinar a energia de ativa??o aparente da remo??o do surfactante (CTMABr) nos poros do MCM-41. As an?lises possibilitaram a caracteriza??o morfol?gica, identificando a presen?a da estrutura hexagonal t?pica dos materiais mesoporosos, assim como das bandas caracter?sticas do MCM41 e do ferro.
75

Avalia??o da incorpora??o combinada dos res?duos de cascalho de perfura??o de po?o de petr?leo e de polimento do porcelanato em cer?mica vermelha

Silva, Moacir Guilhermino da 10 February 2012 (has links)
Made available in DSpace on 2014-12-17T14:07:20Z (GMT). No. of bitstreams: 1 MoacirGS_TESE.pdf: 4771867 bytes, checksum: f93165e08f62a97944b6eed01b488995 (MD5) Previous issue date: 2012-02-10 / Among the industries, those that produce ceramic porcelain for use in construction industry and oil, during the exploration and production period, play an important role in the production of waste. Much research has been carried out both by academia and the productive sector, sometimes reintroducing them in the same production line that generated them, sometimes in areas unrelated to their generation, as in the production of concrete and mortar for the construction, for example, but each one in an isolated way. In this research, the aim is to study the combined incorporation of the waste drill cuttings of oil well and the residue of the polishing of porcelain, generated in the final stage of finishing of this product in a clay matrix, for the production of red pottery, specifically bricks, ceramic blocks and tiles. The clay comes from the municipality of S?o Gon?alo, RN, the drilling waste is from the Natal basin, in Rio Grande do Norte, and the residue of the polishing proceeds from a ceramic porcelain of the State of Para?ba. For this purpose, we used a mixture of a plastic clay with a non-plastic, in a ratio of 50% each, settling formulations with the addition of these two residues in this clay matrix. In the formulations, both residues were incorporated with a minimum percentage of 2.5% and maximum of 12.5%, varying from 2.5% each, in each formulation, which the sum of the waste be no more than 15%. It should be noted that the residue of the polishing of ceramic porcelain is a IIa class (not inert). The materials were characterized by XRF, XRD, TG, DTA, laser granulometry and the plasticity index. The technological properties of water absorption, apparent porosity, linear shrinkage of burning, flexural tensile strength and bulk density were evaluated after the sintering of the pieces to 850 ?C, 950 ?C and 1050 ?C, with a burning time of 3 hr, 3 hr and 30 minutes, and 3 hr and 50 minutes, respectively, with a heating rate of 10 ?C/minute, for all formulations and landing of 30 minutes. To better understand the influence of each residue and temperature on the evaluated properties, we used the factorial planning and its surfaces of response for the interpretation of the results. It was found that the temperature has no statistical significance at a 95% of reliability level in flexural tensile strength and that it decreases the water absorption and the porosity, but increases the shrinkage and the bulk density. The results showed the feasibility of the desired incorporation, but adjusting the temperature to each product and formulation, and that the temperatures of 850 ?C and 950 ?C were the one that responded to the largest number of formulations / A ind?stria de produ??o de porcelanatos para uso na constru??o civil e a do petr?leo, na fase de explora??o e produ??o, exercem um papel importante na produ??o de res?duos. Muitas pesquisas t?m sido realizadas tanto pela academia quanto pelo setor produtivo, ora reintroduzindo esses res?duos na mesma linha de produ??o que os gerou, ora em setores alheios ao de sua gera??o, como na produ??o de concretos e argamassas para a constru??o civil, por exemplo, mas cada um de forma isolada. O objetivo desta pesquisa ? estudar a incorpora??o combinada do res?duo de cascalho de perfura??o de po?o petrol?fero e do res?duo do polimento do porcelanato, gerado na fase de acabamento final do produto, numa matriz argilosa, para a produ??o de cer?mica vermelha - especificamente tijolos, blocos cer?micos e telhas. A argila utilizada ? oriunda do munic?pio de S?o Gon?alo do Amarante, RN; o res?duo de perfura??o, da bacia potiguar, no Rio Grande do Norte; e o do polimento ? de uma cer?mica de porcelanato do Estado da Para?ba. Utilizou-se a mistura de uma argila pl?stica com uma n?o pl?stica, numa propor??o de 50 % de cada uma (que ? o percentual de mistura adotado na cer?mica fornecedora dessa argila), estabelecendo-se formula??es com a incorpora??o dos dois res?duos nessa matriz argilosa. Nas formula??es, os dois res?duos foram incorporados com um percentual m?nimo de 2,5 % e m?ximo de 12,5 %, variando-se em 2,5 % cada um, em cada formula??o, de modo que a soma dos res?duos fosse no m?ximo 15 %. ? oportuno registrar que o res?duo do polimento do porcelanato ? de classe IIa (n?o inerte). Os materiais foram caracterizados por FRX, DRX, TG, DTA, granulometria a laser e pelo ?ndice de plasticidade. As propriedades tecnol?gicas de absor??o de ?gua, porosidade aparente, retra??o linear de queima, tens?o de ruptura ? flex?o e massa espec?fica aparente, foram avaliadas ap?s a sinteriza??o das pe?as a 850 ?C, 950 ?C e 1050 ?C, com ciclo de queima de 3 h , 3 h e 30 min e 3 h e 50 min, respectivamente, com taxa de aquecimento de 10 ?C/min. e patamar de 30 min., para todas as formula??es. Para melhor compreender-se a influ?ncia de cada res?duo e de cada temperatura nas propriedades avaliadas, utilizou-se o planejamento fatorial e suas superf?cies de resposta para interpreta??o dos resultados. Verificou-se que a temperatura n?o tem signific?ncia estat?stica no n?vel de 95 % de confiabilidade na tens?o de ruptura ? flex?o e que ela diminui a absor??o de ?gua e a porosidade, mas aumenta a retra??o e a massa espec?fica aparente. Os resultados mostraram a viabilidade da incorpora??o pretendida, adequando-se a temperatura a cada produto e cada formula??o, e as temperaturas de 850 ?C e 950 ?C foram as que atenderam ao maior n?mero de formula??es
76

O circuito espacial da ind?stria de cer?mica vermelha no serid? potiguar

Nascimento, Judicleide de Azevedo 07 April 2011 (has links)
Made available in DSpace on 2015-03-13T17:10:46Z (GMT). No. of bitstreams: 1 JudicleideAN_DISSERT.pdf: 1718775 bytes, checksum: 1c64b7a22a787d96b10f62b600bd2ba2 (MD5) Previous issue date: 2011-04-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This research has as an empirical universe, the productive territory of red ware in the Serid? region of Rio Grande do Norte. In the last years this territory has gone through a process of appropriation that has been substantially changing the environmental and social dynamism of the place. However, the industry of red ware has been focusing in some areas, mainly, in the county of Parelhas and Carna?ba dos Dantas. From this point of view, the aim of this work consists in analyze the use of these areas by the red ware industry and the transformations occurred with the expansion of the number of industries and the productivity raise, that requires bigger amounts of earthenware and wood, resources that are low in referred territory. As the result of this process, the suitable alternative has been to acquire inputs in other Rio Grande do Norte counties, as well as in Para?ba counties. To reach the proposed objective, the methodology of this work was consisted of bibliographic and empirical research, regarding the occupation that this activity covers in the Serid? region. From the information obtained during the research, it can be stated that the inputs to the production execution in the red ware industry are acquired in the geographic nearby lands. The analysis of the stages of the production(acquisition of raw material, production and commercialization) showed that the activity acts in a continuous area, having as principal consumer market other northeastern states and the state of Par?. The present study revealed that the pottery activity is set as untenable, because of non-stopping use of the argil and wood, resources that are vanishing from the area, which consume causes a many problems such as deforestation and erosion. Besides, the sale of productive lands for the red ware industries makes harder its good use by the familiar agriculturists in the development of agriculture and cattle raising activity, which for many times is the main economic activity of the place. The precariousness reveals in the constant accidents at work, that most of them are neglected by the local authorities, without any penalty to the industries. Therefore, the industry of red ware in Serid? uses the territory as a resource, leaving its environmental problems that my compromise the quality of life of the actual and future generations / Esta pesquisa tem como universo emp?rico, o territ?rio produtor de cer?mica vermelha no Serid? potiguar. Nos ?ltimos anos esse territ?rio passou por um processo de apropria??o que tem alterado substancialmente a din?mica social e ambiental do lugar. No Serid?, a ind?stria de cer?mica vermelha tem se concentrado em algumas ?reas, sobretudo, nos munic?pios de Parelhas e Carna?ba dos Dantas. Nesta perspectiva, o objetivo desse trabalho consiste em analisar o uso do territ?rio pela ind?stria de cer?mica vermelha e as transforma??es ocorridas com a expans?o no n?mero de ind?strias e no aumento da produtividade, o que requer maiores quantidades de argila e de lenha, recursos escassos no referido territ?rio. Em decorr?ncia desse processo, a alternativa encontrada tem sido adquirir os insumos em outros munic?pios do Rio Grande do Norte, como tamb?m em munic?pios paraibanos. Para alcan?ar o objetivo proposto, o encaminhamento metodol?gico envolveu pesquisa bibliogr?fica e emp?rica, considerando a espacializa??o que essa atividade abrange no territ?rio seridoense. A partir das informa??es obtidas durante a pesquisa pode-se afirmar que os insumos para a realiza??o da produ??o na ind?stria de cer?mica vermelha s?o adquiridos no seu entorno geogr?fico. A an?lise das etapas do circuito de produ??o (aquisi??o da mat?ria-prima, produ??o e comercializa??o) mostrou que esta atividade atua numa ?rea cont?nua, tendo como principal mercado consumidor os demais estados do Nordeste e o estado do Par?. O presente estudo revelou ainda que a atividade ceramista configura-se como insustent?vel, haja vista a recorr?ncia permanente ? argila e ? lenha, insumos escassos no territ?rio, cuja aquisi??o provoca uma s?rie de problemas como o desmatamento e a eros?o. Al?m disso, a venda dos solos f?rteis para as cer?micas dificulta o seu aproveitamento pelos agricultores familiares, no desenvolvimento das atividades agropecu?rias, que muitas vezes configura-se na principal atividade econ?mica da propriedade. A precariedade da atividade se revela nos constantes acidentes de trabalho, que na grande maioria, s?o negligenciados pelas autoridades locais, sem aplica??o de nenhuma penalidade ?s empresas. Assim, a ind?stria de cer?mica vermelha no Serid? usa o territ?rio de forma seletiva e excludente, deixando s?rias problem?ticas ambientais, as quais podem comprometer a qualidade de vida das atuais e futuras gera??es
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Avalia??o dos impactos ambientais gerados por uma industria cer?mica t?pica da Regi?o do Serid?/RN

Nascimento, Wald?cio S?vio dos Anjos do 02 March 2007 (has links)
Made available in DSpace on 2014-12-17T14:58:25Z (GMT). No. of bitstreams: 1 WaldecioSAN.pdf: 2259202 bytes, checksum: 5cc6fb8a72468793d81d509b30ee2013 (MD5) Previous issue date: 2007-03-02 / The present work deals with an evaluation of the environmental impacts arised from a typical ceramics industry located in the Serid? region of Rio Grande do Norte State. That region contains the largest State s producing basin of red ceramics. The district of Parelhas stands out as the largest producing nucleus. The studied company is located in the rural zone of Parelhas, it was selected as study object because it possesses a great part of the representative characteristics of the Region s ceramics park as a whole. Impacts produced at the implantation and operation phases of the Company had been evaluated, being this last phase subdivided in stages of the productive process. Among found adverse impacts, they are distinguished: losses in air quality, undesirable noises, microclimatic alterations, impoverishment of the ground, elimination of the vegetal covering, agricultural exodus, crisis in cattle agriculture and, superficial and underground water contamination, beyond risks ocupational diseases and industrial accidents. The Leopold s interactive matrix, that summarizes results of the work, was presented in form of 15 (fifteen) tables that display impacts classified in qualitative and quantitative way. Totally, 175 (one hundred and seventy-five) significant impacts produced by this Company had been identified, being 114 (one hundred and fourteen) negative, 38 (thirty-eight) positive and 23 (twenty-three) among mixed, indefinite and inert ones. In the work, before the evaluation of impacts properly said, it was constructed a diagnostic table of the ambient situation at a previous moment to implantation of the Company, elaborated on basis of inferences and historical researches. It was proposed still, mitigative steps for adverse impacts identified, as also elaborated a program to accompaniment and observing that the fulfilment of indicated mitigative steps guarantees. The final part of the work contemplates conclusions and suggestions that aim to influence positively the presented sight in terms of environmental management / O presente trabalho trata de uma avalia??o de impactos ambientais gerados por uma ind?stria cer?mica t?pica da regi?o do Serid? do Rio Grande do Norte. Essa regi?o abriga a maior bacia produtora de cer?mica vermelha do Estado, destacando-se o munic?pio de Parelhas como maior n?cleo produtor. A empresa estudada localiza-se na zona rural do munic?pio de Parelhas, foi escolhida como objeto de estudo por reunir boa parte das caracter?sticas representativas do parque cer?mico da Regi?o como um todo. Foram avaliados os impactos produzidos nas fases de implanta??o e opera??o da Empresa, sendo esta ?ltima fase subdividida em etapas do processo produtivo. Entre os impactos adversos encontrados, destacam-se: perdas na qualidade do ar, ru?dos indesej?veis, altera??es no microclima, empobrecimento do solo, elimina??o da cobertura vegetal, ?xodo rural, crise na agricultura e pecu?ria, contamina??o de ?guas superficiais e subterr?neas, al?m de riscos de doen?as profissionais e acidentes de trabalho. A matriz interativa de Leopold, que resume os resultados do trabalho, foi apresentada na forma de 15 (quinze) tabelas que exp?em os impactos classificados de modo qualitativo e quantitativo. No total, foram identificados 175 (cento e setenta e cinco) impactos significativos produzidos por essa Empresa, sendo 114 (cento e quatorze) negativos, 38 (trinta e oito) positivos e outros 23 (vinte e tr?s) entre mistos, indefinidos e neutros. No trabalho, antes da avalia??o de impactos propriamente dita, foi constru?da uma tabela de diagn?stico da situa??o ambiental num momento anterior ? implanta??o da Empresa, elaborada com base em infer?ncias e pesquisas hist?ricas. Foram propostas ainda, medidas mitigadoras para impactos adversos identificados, como tamb?m elaborado um programa de acompanhamento e monitoramento que garanta o cumprimento das medidas mitigadoras indicadas. A parte final do trabalho contempla as conclus?es e sugest?es que visem influenciar positivamente o quadro apresentado em termos de gest?o ambiental
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Influ?ncia do teor e granulometria da calcita e da temperatura de sinteriza??o no desenvolvimento de massas cer?micas para revestimento poroso(BIII) / Influence of particle size and content of calcite and sintering temperature on the development of porous ceramic body coating

Galdino, Jos? Nildo 08 April 2010 (has links)
Made available in DSpace on 2014-12-17T15:01:51Z (GMT). No. of bitstreams: 1 JoseNG_TESE.pdf: 4686361 bytes, checksum: ece8f07ff848703fdc4412907a924e10 (MD5) Previous issue date: 2010-04-08 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work aims at studying the influence of the concentration of calcite, its grain size and sintering temperature to obtain porous coating formulations that meet the design specifications. The experiments involved the physical-chemical and mineralogical caracterization of the raw materials, and mechanical tests on specimens dried and sintered, performing a planning mixture and factorial experiment, using the response surface methodology. The ceramic bodies studied were prepared by dry process, characterized, placed in conformity by uniaxial pressing and sintered at temperatures of 940 ? C, 1000?C, 1060?C, 1120?C and 1180?C using a fast-firing cycle. The crystalline phases formed during sintering at temperatures under study, revealed the presence of anorthite and wolastonite, and quartz-phase remaining. These phases were mainly responsible for the physical and mechanical properties of the sintered especimens. The results shown that as increases the participation of carbonate in the composition of ceramic bodies there is an increase of water absorption and a slight reduction in linear shrinkage for all sintering temperatures. As for the mechanical strength it was observed that it tended to decrease for sintering at temperatures between 940 ? C and 1060 ? C and to increase for sintering at temperatures above 1060 ? C occurring with greater intensity for compositions with higher content of calcite. The resistence decreased with increasing participation of quartz in all sintering temperatures. The decrease in grain size of calcite caused a slight increase in water absorption for formulation with the same concentration of carbonate, remaining virtually unchanged the results of linear shrinkage and mechanical strength. In conclusion, porous ceramic coating (BIII) can be obtained using high concentrations of calcite and keeping the properties required in technical standards and that the particle size of calcite can be used as tuning parameter for the properties of ceramic products. / Este trabalho objetiva estudar a influ?ncia da concentra??o de calcita, sua granulometria e temperatura de sinteriza??o na obten??o de formula??es para revestimento poroso que atendam as especifica??es da norma. Os experimentos envolveram a caracteriza??o f?sico qu?mica e mineral?gica das mat?rias-primas, e ensaios mec?nicos nos corpos de prova secos e sinterizados, precedendo-se de um planejamento de experimento de mistura e fatorial, com o uso da metodologia de superf?cie de resposta. As massas cer?micas estudadas foram preparadas pelo processo via seca, caracterizada, conformada por prensagem uniaxial e sinterizadas nas temperaturas de 940?C, 1000?C, 1060?C, 1120?C, e 1180?C utilizando um ciclo de sinteriza??o r?pido. As fases cristalina formadas durante a sinteriza??o nas temperaturas em estudo, revelaram a presen?a de anortita e wolastonita, al?m de quartzo com fase remanescente. Estas fases foram as principais respons?veis pelas propriedades f?sico-mec?nica dos corpos de provas sinterizados. Verificou-se que conforme se aumenta a participa??o do carbonato na composi??o das massas cer?micas ocorre um incremento de absor??o de ?gua e uma pequena redu??o da retra??o linear para todas as temperaturas de sinteriza??o. J? para a resist?ncia mec?nica houve uma tend?ncia de redu??o para sinteriza??o entre 940?C e 1060?C e aumento para sinteriza??o acima da temperatura de 1060?C ocorrendo com maior intensidade para formula??es com maior teor de calcita, e houve diminui??o da resist?ncia com o aumento da participa??o do quartzo em todas as temperaturas de sinteriza??o. A diminui??o da granulometria da calcita provocou um leve aumento na Absor??o de ?gua para formula??o com a mesma concentra??o desse carbonato mantendo praticamente inalterados os resultados de retra??o linear e resist?ncia mec?nica. Conclui-se que produtos cer?micos para revestimento poroso (BIII) podem ser obtidos utilizando altas concentra??es de calcita e mantendo-se as propriedades exigidas em normas t?cnicas e que a granulometria da calcita pode ser usada como par?metro de ajuste para as propriedades dos produtos cer?micos

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