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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

Desenvolvimento de filtro cartucho de poliimida para altas temperaturas com resina ep?xi DGEBA e novo agente de cura

Ceron, Luciano Peske 27 March 2012 (has links)
Made available in DSpace on 2015-04-14T13:58:48Z (GMT). No. of bitstreams: 1 438589.pdf: 4872260 bytes, checksum: 7a7d4afb2e3e9cf2c377c01b09f71361 (MD5) Previous issue date: 2012-03-27 / This study evaluated the development of polyimide filter cartridge for use in high temperature particulate filtration of LDPE in the petrochemical industry. An epoxy prepared with DGEBA resin and a new curing agent formulation of polyaminoamide:amine 9:1 was evaluated for gluing pleating non-woven fabric to the cartridge metal borders. The research first step was to characterize LDPE particles (screening and SEM) of polyimide fiber (TGA and FTIR), polyimide non-woven fabric, polyester, and polyacrylonitrile copolymer (SEM) and epoxy (TGA, FTIR and DSC). The study second step was application in non-woven fabric for its dimensional alteration dimensional, permeability and inflammability. Polyamide non-woven fabric mechanical properties was analyzed by tensile strength under several temperatures in relation to time. Multifactor experiments for non-woven fabric filtration were analyzed using ANOVA. The third step was attributed to choosing an ideal formulation between DGEBA resin and curing agent through tensile strength test: regarding its preparation conditions, compared to other curing agents, thermal tests and humidity absorbance. Epoxy impact resistance was analyzed by izod. The last step was dedicated to cartridge filtration tests, laboratorial and industrial, in order to verify the construction set efficacy. Laboratory results obtained with cartridge prototypes show a better filtration performance with polyimide compared to other non-woven fabrics due its rapid onset of filtration cake, smaller load loss and low emission. After twenty-five months of industrial use of the polyimide cartridge filter with epoxy resin, it was observed good filtration conditions under up to 240?C with low particle emission, controlled load loss and power reuse in the industrial process. / Neste estudo avaliou-se o desenvolvimento de filtro cartucho de poliimida para uso em altas temperaturas, para filtra??o de particulados de PEBD em ind?stria petroqu?mica. Foi pesquisado um ep?xi, preparado com resina DGEBA e nova formula??o de agente de cura de poliaminoamida:amina 9:1, para a colagem do n?o tecido plissado nas extremidades met?licas do cartucho. A primeira etapa da pesquisa consistiu na caracteriza??o dos particulados de PEBD (peneiramento e MEV), da fibra de poliimida (TGA e FTIR), dos n?o tecidos de poliimida, do poli?ster e poliacrilonitrila copol?mero (MEV) e do ep?xi (TGA, FTIR e DSC). A segunda parte do estudo foi de desempenho em n?o tecidos, quanto ? altera??o dimensional, permeabilidade e inflamabilidade. Avaliou-se por tra??o as propriedades mec?nicas do n?o tecido de poliimida, submetido a diversas temperaturas em fun??o do tempo. Por meio da ANOVA realizou-se a an?lise dos experimentos multifatoriais de simula??o de filtra??o em n?o tecidos. A terceira parte envolveu a escolha da formula??o ideal entre resina DGEBA e agente de cura, atrav?s de ensaios de tra??o: quanto ?s condi??es de preparo, comparativos com outros agentes de curas, ensaios t?rmicos e absor??o de umidade. A resist?ncia ao impacto do ep?xi foi avaliada por izod. A ?ltima etapa foi dedicada aos testes de filtra??o em cartucho, laboratorial e industrial, para verificar a efic?cia do conjunto da constru??o. Os resultados laboratoriais obtidos com prot?tipos de cartuchos demonstraram a melhor performance de filtra??o com poliimida comparada aos outros n?o tecido, devido a r?pida forma??o da torta de filtra??o, pouca perda de carga e baixa emiss?o. Ap?s vinte e cinco meses de aplica??o industrial do filtro cartucho de poliimida com resina ep?xi, constatou-se boas condi??es de filtra??o at? 240?C, com baixa emiss?o de particulados, perda de carga controlada e reaproveitamento de energia no processo industrial.
2

Influ?ncia da granulometria e taxas de filtra??o no tratamento de ?gua utilizando dupla filtra??o / Influence of particle size and filtration rates for water treatment using double filtration

Cirne, Jos? Raniery Rodrigues 30 September 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-01-14T19:02:59Z No. of bitstreams: 1 JoseRanieryRodriguesCirne_DISSERT.pdf: 2528321 bytes, checksum: 2e7ed59317d15a3342a9ad456713f456 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-01-15T20:46:10Z (GMT) No. of bitstreams: 1 JoseRanieryRodriguesCirne_DISSERT.pdf: 2528321 bytes, checksum: 2e7ed59317d15a3342a9ad456713f456 (MD5) / Made available in DSpace on 2016-01-15T20:46:10Z (GMT). No. of bitstreams: 1 JoseRanieryRodriguesCirne_DISSERT.pdf: 2528321 bytes, checksum: 2e7ed59317d15a3342a9ad456713f456 (MD5) Previous issue date: 2014-09-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / A contamina??o dos mananciais de abastecimento p?blico de ?gua por res?duos originados pelas atividades antr?picas vem trazendo diversos riscos para a sa?de humana. Dentre as consequ?ncias de contaminantes pode-se destacar a flora??o de microalgas e cianobact?rias, que t?m o potencial de produzir toxinas perigosas para os seres humanos, e a presen?a de subst?ncias h?micas que s?o geradas pela decomposi??o da mat?ria org?nica natural (MON), tal como a vegeta??o, que quando encontradas em mananciais para abastecimento p?blico, apresentam aspectos negativos conferindo cor elevada, odor e sabor. A tecnologia de dupla filtra??o apresenta boa efici?ncia em ?guas com presen?a de cianobact?rias e varia??es distintas de qualidade. Portanto, este trabalho teve como objetivo avaliar o comportamento da t?cnica de dupla filtra??o com pr?-oxida??o, para a potabiliza??o da ?gua da Lagoa de Extremoz-RN, que atualmente apresenta concentra??es elevadas de cianobact?rias. A pesquisa se resumiu em quatro fases. A primeira fase voltou-se para ensaios est?ticos em equipamento de jarteste em laborat?rio e as fases subsequentes foram testadas em uma Instala??o Piloto de Dupla Filtra??o. Para a segunda e terceira fase foram testadas taxas de filtra??o de 120 e 180 m3 /m2 .dia para filtros ascendentes de pedregulhos e 160 e 240 m3 /m2 .dia filtros r?pidos descendentes de areia. A ?ltima fase objetivou avaliar a dupla filtra??o com pr?-oxida??o. Os resultados encontrados na instala??o piloto de dupla filtra??o demonstraram que o filtro ascendente de pedregulho 4, que apresentava a menor granulometria, demonstrou a melhor efici?ncia e as melhores m?dias de turbidez e cor aparente. O Filtro r?pido descendente de areia 1 foi mais eficiente na remo??o de turbidez alcan?ando remo??o em torno de 100%. Portanto, comprovou-se que quanto menor a granulometria dos filtros, maior a efici?ncia de remo??o de turbidez. O uso da pr?-oxida??o favoreceu a remo??o de cor no final dos ensaios, chegando a um percentual de remo??o em torno de 60%. Com rela??o ? remo??o da turbidez, a t?cnica de dupla filtra??o se mostrou eficiente. Por?m a remo??o de cor e de cianotoxinas presentes na ?gua s? foi eficiente com o aux?lio de um oxidante / The contamination of water sources of public drinking by waste originated by anthropogenic activities has brought various risks to human health. Among the consequences of such activities can highlight the bloom of microalgae and cyanobacteria, which have the potential to produce toxins dangerous to humans, and the presence of humic substances that are generated by the decomposition of natural organic matter (NOM), such as vegetation. When found in water sources for public supply, present negative aspects conferring high color, odor and taste. The double filtration technology has good efficiency in water with the presence of cyanobacteria and different quality variations. Therefore, this study aimed to evaluate the behavior of the technique of double filtration with pre-oxidation for water purifiers the lagoon of Extremoz-RN, which currently has high concentrations of cyanobacteria. The research is summarized in four phases: the first phase turned to static tests in jarteste equipment in the laboratory and subsequent phases were tested in the Pilot Plant of Double Filtration. For the second and third stage filtration rates were tested filtration rates of 120 and 180 m3 / m2 .day for ascending boulders filters and 160 and 240 m3 / m2 .day in the filters in quick sand descendants. The last phase aimed to evaluate the double filtration with pre-oxidation. The results demonstrated that the system could produce double filtration in all trials of good quality water according to the Decree n?. 2914/11 of the Ministry of Health. The use of preoxidation favored the removal of microcystin and color at the end of the tests, reaching a percentage of color removal around 60%. The analysis of variance in the data, enabled prove that the filtration rates of 180 m3 / m2.d the gravel filter and 240 m3 /m2 .d in rapid filters, were the most significant for the removal of turbidity. The ascending filter of boulder 4 with particle size finer filter layer showed the best performance and the best means of turbidity and apparent color. The rapid filter downward 1 was more efficient in removing turbidity reaching removal about 100%
3

Avalia??o da filtra??o de fluidos de perfura??o n?o Newtonianos utilizando a teoria simplificada da filtra??o / Analysis of non Newtonian drilling fluids filtration using the simplified theory of filtration

SILVA, Bianca Rangel Antunes da 21 December 2017 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-05-10T18:21:02Z No. of bitstreams: 1 2017 - Bianca Rangel Antunes da Silva.pdf: 2187606 bytes, checksum: 927fe528eb48db49953e8f982d4320d5 (MD5) / Made available in DSpace on 2018-05-10T18:21:02Z (GMT). No. of bitstreams: 1 2017 - Bianca Rangel Antunes da Silva.pdf: 2187606 bytes, checksum: 927fe528eb48db49953e8f982d4320d5 (MD5) Previous issue date: 2017-12-21 / During the drilling of oil wells, the pressure differential between the rock formation and the annular region can cause a filtration process and consequent invasion of drilling fluid into the rocks, causing irreversible damage to the well. Therefore, studies to control the properties of the well formed mudcake are fundamental. The mudcake formed should be thin and of low permeability, thus minimizing the filtration and the invasion of the fluid. The main purpose of this work was to study the characteristics of the filtration pie formed during the drilling process of oil wells, using non-Newtonian fluids that follow the Power law model, and applying the simplified theory of filtration adapted for non-Newtonian fluids to achieve the specific objective that was the lifting of the parameters of permeability, porosity, thickness and correction factor obtained from experimental data of filtered volume versus time, in Static conditions, at different pressures. Experimental results were obtained in different filtration conditions (pressure, viscosifier agent and weighting material) seeking to compare and know the mechanisms that control filtration in static conditions. Filtration tests were carried out at 300 psi, 500 psi and 700 psi, using a HTHP cell and prepared non-Newtonian drilling fluids containing xanthan gum (XG) and carboxymethylcellulose (CMC) as viscosifier agent, in addition to calcite and barite. Filtration parameters such as permeability, porosity, pie thickness, filtration time and filtered volume have been evaluated. The permeability of the pie was determined, with the aid of a software of estimation of parameters, using the simplified theory of filtration adapted for non Newtonian fluids proposed by Massarani and Coelho de Castro(1980). The results obtained were confronted with those obtained by other methodologies. The experimental tests also showed that the properties of the pie vary with the filtration pressure. / Durante o processo de perfura??o de po?os de petr?leo, o diferencial de press?o entre a forma??o rochosa e a regi?o anular pode ocasionar um processo de filtra??o e consequente invas?o de fluido de perfura??o nas rochas, causando opera??es irrevers?veis ao po?o. Por isso, s?o fundamentais estudos para controlar as propriedades da torta de filtra??o formada na parede do po?o. A torta formada deve ser fina e de baixa permeabilidade, minimizando assim a filtra??o e a invas?o do fluido. Este trabalho teve como objetivo principal estudar as caracter?sticas da torta de filtra??o formada durante o processo de perfura??o de po?os de petr?leo, utilizando fluidos n?o Newtonianos que seguem a lei da pot?ncia,e aplicando a teoria simplificada da filtra??o adaptada para fluidos n?o Newtonianos para atingir o objetivo espec?fico que foi o levantamento dos par?metros de permeabilidade, porosidade, espessura e fator de corre??o obtidos a partir de dados experimentais de volume de filtrado versus tempo, em condi??es est?ticas, em diferentes press?es.Foram obtidos resultados experimentais em diferentes condi??es de filtra??o (press?o, viscosificante e adensante) buscando comparar e conhecer os mecanismos que controlam a filtra??o em condi??es est?ticas. Foram realizados ensaios de filtra??o a 300 psi, 500 psi e 700 psi, utilizando uma c?lula HTHP e preparados fluidos de perfura??o n?o-Newtonianos contendo Goma Xantana (GX) e carboximetilcelulose (CMC) como viscosificantes, al?m de barita e calcita. Foram avaliados os par?metros da filtra??o como permeabilidade, porosidade, espessura da torta, tempo de filtra??o e volume de filtrado. A permeabilidadeda torta foideterminada, com o aux?lio de umsoftware de estima??o de par?metros, utilizando-sea teoria simplificada da filtra??o adaptada para fluidos n?o Newtonianos proposta por Massarani e Coelho de Castro (1980). Os resultados obtidos foram confrontados com os obtidos por outras metodologias. Os ensaios experimentais mostraram tamb?m que as propriedades da torta variam com a press?o de filtra??o.
4

Estudo sobre tratamento t?rmico e mudan?a superficial da diatomita de Puna?/RN para o desenvolvimento de um auxiliar de filtra??o

Nascimento, Carlos Rener do 30 December 2013 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2015-10-14T12:07:35Z No. of bitstreams: 1 CarlosRenerDoNascimento_DISSERT.pdf: 10760871 bytes, checksum: 485a7679240639021e896c02d64ad53a (MD5) / Approved for entry into archive by Maria Maia (aniolly@bczm.ufrn.br) on 2015-10-14T12:39:56Z (GMT) No. of bitstreams: 1 CarlosRenerDoNascimento_DISSERT.pdf: 10760871 bytes, checksum: 485a7679240639021e896c02d64ad53a (MD5) / Made available in DSpace on 2015-10-14T12:39:56Z (GMT). No. of bitstreams: 1 CarlosRenerDoNascimento_DISSERT.pdf: 10760871 bytes, checksum: 485a7679240639021e896c02d64ad53a (MD5) Previous issue date: 2013-12-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / A diatomita ? um material natural que possui in?meras aplica??es devido ?s mudan?as nas suas propriedades f?sica e qu?mica ap?s processamento. Atualmente, ? utilizada na ind?stria como isolante ac?stico, auxiliar de filtra??o e carga industrial. O material filtrante deve apresentar composi??o qu?mica de material inerte, o que confere ? diatomita um alto valor comercial e desempenho, n?o encontrados em outros materiais particulados, para esta aplica??o. A diatomita sofre altera??es superficiais ap?s tratamento t?rmico em altas temperaturas, a partir de 800?C, apresentando propriedades que permitem sua aplica??o nas ind?strias aliment?cias, de bebidas, farmac?uticas, t?xteis e cosm?ticas. Neste trabalho, desenvolveu-se um estudo sobre tratamento t?rmico em diatomita natural a fim de adequar suas propriedades ? aplica??o como auxiliar de filtra??o. Os tratamentos t?rmicos foram realizados em forno aberto nas temperaturas de 800?C, 1000?C e 1200?C, por um tempo de 24 horas. Foram adicionados tamb?m reagentes na constitui??o das amostras em an?lise. Os reagentes usados foram, o carbonato de s?dio (Na2CO3) e o cloreto de s?dio (NaCl). As amostras foram caracterizadas por difra??o de raios-x, fluoresc?ncia de raios-x, microscopia eletr?nica de varredura, an?lise de distribui??o e tamanho de part?culas, ?rea superficial especifica pelo m?todo BET, e volume de poros pelo m?todo BJH. Os resultados mostraram uma redu??o na porosidade do material bem como um incremento significativo da ?rea superficial especifica ap?s tratamento t?rmico e com os reagentes na propor??o de 3% em peso. As diatomitas, ap?s tratamento t?rmico, sofreram altera??es na sua colora??o, variando nas cores branca, creme e bege, que interferem diretamente na velocidade do processo de filtra??o de materiais. Todos os resultados obtidos antes e ap?s tratamento t?rmico do material foram comparados aos valores obtidos para as amostras j?a usadas industrialmente, da ind?stria brasileira e americana, que foram caracterizadas atrav?s dos mesmos m?todos experimentais realizados com as amostras em estudo, e indicaram uma efici?ncia promissora ao material estudado da regi?o de Puna? - RN, ap?s seu processamento; adi??o de reagentes e tratamento t?rmico, como elemento na composi??o de filtrante. / The diatomite is a natural material that has numerous applications due to changes in their physical and chemical properties after processing. It is currently used in the industry as a sound insulator , filter aid and industrial load . The filter material shall be inert chemical composition , which will diatomite confers a high commercial value and performance not found in other particulate materials , for this application. The diatomite surface undergoes changes after thermal treatment at high temperatures , from 800?C , with properties that enable its application in the food , beverage , pharmaceutical , cosmetic and textiles . In this work , we developed a study on thermal treatment on natural diatomite to adapt their properties to the application as a filter aid . The heat treatments were performed in an open oven at temperatures of 800?C , 1000?C and 1200?C for a time of 24 hours. Reagents were added in the constitution of the samples analyzed. The reagents used were sodium carbonate (Na2CO3 ) and sodium chloride (NaCl) . The samples were characterized by x - ray diffraction , x -ray fluorescence , scanning electron microscopy , analysis and particle size distribution , specific surface area by the BET method , and pore volume by BJH method. The results showed a reduction in porosity of the material as well as a significant increase in specific surface area after heat treatment and the reactants in the ratio of 3 wt%. The diatomaceous earth , after heat treatment , undergone changes in its coloration , varying in white, cream and beige , which directly interferes with the speed of filtration materials process. All results obtained before and after heat treatment of the material with the values obtained for samples already used industrially , Brazilian and American industry , which were characterized using the same test methods performed with the samples in the study were compared and showed promising efficiency when material studied in the region of Puna? - RN , after processing , reagent addition and heat treatment, as an element in the composition of filter .
5

Tratamento combinado da ?gua produzida de petr?leo: filtra??o, adsor??o e foto-Fenton / Combined treatment of oil produced water: filtration, adsorption and photo-Fenton

Carvalho, Patr?cia Cristina de Ara?jo Puglia de 05 August 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-10T16:07:57Z No. of bitstreams: 1 PatriciaCristinaDeAraujoPugliaDeCarvalho_TESE.pdf: 4319409 bytes, checksum: 4b6ca5c028beba5a80abf23ce490b97a (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-10T18:56:57Z (GMT) No. of bitstreams: 1 PatriciaCristinaDeAraujoPugliaDeCarvalho_TESE.pdf: 4319409 bytes, checksum: 4b6ca5c028beba5a80abf23ce490b97a (MD5) / Made available in DSpace on 2017-02-10T18:56:57Z (GMT). No. of bitstreams: 1 PatriciaCristinaDeAraujoPugliaDeCarvalho_TESE.pdf: 4319409 bytes, checksum: 4b6ca5c028beba5a80abf23ce490b97a (MD5) Previous issue date: 2016-08-05 / Ag?ncia Nacional do Petr?leo - ANP / Dentre os res?duos oriundos das opera??es de produ??o de ?leo e g?s ocorre a produ??o de ?gua comumente chamada de ?gua produzida (AP). ? o efluente que mais se destaca, em virtude de seu volume e sua composi??o qu?mica t?xica. Existem diversos tipos de tratamentos qu?mico, f?sico, f?sico-qu?mico e biol?gico, que podem ser combinados visando uma melhor efici?ncia no tratamento de efluentes. O presente trabalho tem como principal objetivo avaliar a combina??o dos processos de filtra??o, adsor??o e foto-Fenton na remo??o dos ?leos e graxas totais (TOG) e carbono org?nico total (TOC) presentes na AP. A filtra??o teve como principal meta a redu??o do TOG e favorecimento da adsor??o, que foi escolhida como segunda etapa para remover o TOC ? melhorar a efici?ncia da etapa seguinte. O foto-Fenton, tem como finalidade, remover a carga org?nica remanescente das etapas anteriores ficando em ?ltimo, devido ao seu maior custo. O processo combinado consiste na utiliza??o de um filtro de areia com granulometria mista (-12+16, + 35, -20 +28 e -12+16 mesh), uma coluna de carv?o ativado vegetal (carv?o ativado da casca do coco de baba?u) e processo foto-Fenton no qual foi utilizado um reator fotoqu?mico de l?mpada de 400 W de vapor de merc?rio. O efluente sint?tico foi preparado a partir de uma mistura de componentes (NaCl, fenol, heptano, xileno, ?gua destilada e petr?leos (15 e 22 API?). O efluente inicial foi passado nas colunas de filtra??o e adsor??o de forma continua at? obten??o de pelo menos 6 L de efluente parcialmente tratado. Ent?o o efluente foi levado para o reator fotoqu?mico para degradar os contaminantes remanescentes dos processos anteriores. Considerando a redu??o de TOG, o processo combinado obteve uma efici?ncia e 98,8 %, sendo somente na etapa da filtra??o uma redu??o de 90%. Com rela??o a redu??o do TOC, a efici?ncia total do processo combinado foi de 99%, sendo as etapas de adsor??o e foto-Fenton as de maior efici?ncia. A combina??o dos processos de filtra??o, adsor??o e foto-Fenton mostrou ser eficiente tanto na redu??o do TOG quanto na redu??o de TOC da ?gua produzida. / During the exploitation of oil and gas onshore and offshore, it is also simultaneously the production of water commonly called produced water or production water. Produced water (PW) is the that most prominent wastewater because of its large volume and its toxic chemical composition. There are several types of chemical, physical, physico-chemical and biological treatments that can be combined to better efficiency in wastewater treatment. This aims to evaluate the combination of filtration processes, adsorption and photo-Fenton in the removal of oils and greases Total (TOG) and total organic carbon (TOC) in the AP. The filtration had the main goal to reduce the TOG and facilitate adsorption which was chosen as a second step to remove the TOC is to improve efficiency in the fallowing step. The photo-Fenton, aims to remove the remaining load organic from the previous steps. The combined process consists of using a sand filter with mixed grain size (-12 + 16, + 35, -20 + 28 and -12 + 16 mesh), vegetable activated carbon column (activated carbon from babassu bark) and photo-Fenton process which was used in a photochemical reactor of 400 W mercury vapor lamp. The synthetic effluent was prepared from a mixture of components (NaCl, phenol, heptane, xylene, distilled water and oils (15 and 22 API ?). The initial effluent was passed into the filter column and adsorption continuously to obtain the least 6 L of partially treated effluent. Then the effluent was taken for the photochemical reactor to degrade the remaining contaminants of the prior processes. Considering the reduction TOG, the combined process and obtained a 98.8% efficiency, with only the filtration step a reduction of 90%. With regard to reduction of the TOC, the overall efficiency of the combined process was 99%, with the steps of absorption and photo-Fenton the greater efficiency. a combination of filtration processes, absorption and photo-Fenton was effective in both reducing the TOG as the TOC reduction of the water produced.
6

Intera??es entre a carboximetilcelulose, carbonato de c?lcio e bentonita: repercuss?es sobre as propriedades dos fluidos de perfura??o aquosos

Santana, Keila Regina 16 May 2014 (has links)
Made available in DSpace on 2014-12-17T15:42:30Z (GMT). No. of bitstreams: 1 KeilaRS_TESE.pdf: 2025404 bytes, checksum: f62ed0f0a6e3ff3ceed81829e8165b40 (MD5) Previous issue date: 2014-05-16 / Petr?leo Brasileiro SA - PETROBRAS / The role of carboxymethylcellulose (CMC) in association to calcium carbonate particles (CaCO3) in most water-based drilling fluids is to reduce the fluid loss to the surrounding formation. Another essential function is to provide rheological properties capable of maintaining in suspension the cuttings during drilling operation. Therefore, it is absolutely essential to correlate the polymer chemical structure (degree of substitution, molecular weight and distribution of substituent) with the physical-chemical properties of CaCO3, in order to obtain the better result at lower cost. Another important aspect refers to the clay hydration inhibitive properties of carboxymethylcellulose (CMC) in drilling fluids systems. The clay swelling promotes an undesirable damage that reduces the formation permeability and causes serious problems during the drilling operation. In this context, this thesis consists of two main parts. The first part refers to understanding of interactions CMC-CaCO3, as well as the corresponding effects on the fluid properties. The second part is related to understanding of mechanisms by which CMC adsorption occurs onto the clay surface, where, certainly, polymer chemical structure, ionic strength, molecular weight and its solvency in the medium are responsible to affect intrinsically the clay layers stabilization. Three samples of carboximetilcellulose with different molecular weight and degree of substitution (CMC A (9 x 104 gmol DS 0.7), CMC B (2.5 x 105 gmol DS 0.7) e CMC C (2.5 x 105 gmol DS 1.2)) and three samples of calcite with different average particle diameter and particle size distribution were used. The increase of CMC degree of substitution contributed to increase of polymer charge density and therefore, reduced its stability in brine, promoting the aggregation with the increase of filtrate volume. On the other hand, the increase of molecular weight promoted an increase of rheological properties with reduction of filtrate volume. Both effects are directly associated to hydrodynamic volume of polymer molecule in the medium. The granulometry of CaCO3 particles influenced not only the rheological properties, due to adsorption of polymers, but also the filtration properties. It was observed that the lower filtrate volume was obtained by using a CaCO3 sample of a low average size particle with wide dispersion in size. With regards to inhibition of clay swelling, the CMC performance was compared to other products often used (sodium chloride (NaCl), potassium chloride (KCl) and quaternary amine-based commercial inhibitor). The low molecular weight CMC (9 x 104 g/mol) showed slightly lower swelling degree compared to the high molecular weight (2.5 x 105 g/mol) along to 180 minutes. In parallel, it can be visualized by Scanning Electron Microscopy (SEM) that the high molecular weight CMC (2.5 x 105 g/mol e DS 0.7) promoted a reduction in pores formation and size of clay compared to low molecular weight CMC (9.0 x 104 g/mol e DS 0.7), after 1000 minutes in aqueous medium. This behavior was attributed to dynamic of interactions between clay and the hydrodynamic volume of CMC along the time, which is result of strong contribution of electrostatic interactions and hydrogen bounds between carboxylate groups and hydroxyls located along the polymer backbone and ionic and polar groups of clay surface. CMC adsorbs on clay surface promoting the skin formation , which is responsible to minimize the migration of water to porous medium. With the increase of degree of substitution, it was observed an increase of pores onto clay, suggesting that the higher charge density on polymer is responsible to decrease its flexibility and adsorption onto clay surface. The joint evaluation of these results indicate that high molecular weight is responsible to better results on control of rheological, filtration and clay swelling properties, however, the contrary effect is observed with the increase of degree of substitution. On its turn, the calcite presents better results of rheological and filtration properties with the decrease of average viii particle diameter and increase of particle size distribution. According to all properties evaluated, it has been obvious the interaction of CMC with the minerals (CaCO3 and clay) in the aqueous medium / O papel da carboximetilcelulose (CMC) em associa??o com o carbonato de c?lcio (CaCO3) na maioria dos fluidos de perfura??o base ?gua ? reduzir a perda de fluido para a forma??o. Outra fun??o essencial ? promover propriedades reol?gicas capazes de manter em suspens?o os cascalhos durante a opera??o de perfura??o. Dessa forma, ? absolutamente essencial correlacionar a estrutura qu?mica do pol?mero (grau de substitui??o, massa molar e distribui??o do substituinte) com as propriedades f?sicoqu?micas do CaCO3, de forma a obter o melhor resultado a mais baixo custo. Outro importante aspecto refere-se ?s propriedades de inibi??o da CMC em rela??o ? hidrata??o de argilas presentes na forma??o rochosa. O inchamento de argilas promove um dano indesej?vel que reduz a permeabilidade da forma??o e causa s?rios problemas durante a perfura??o. Nesse contexto, essa Tese consiste de duas partes principais. A primeira parte refere-se ao entendimento das intera??es CaCO3-CMC, assim como os efeitos correspondentes ?s propriedades do fluido. A segunda parte est? relacionada ao entendimento dos mecanismos pelos quais a adsor??o da CMC ocorre na aresta da argila, onde, certamente, a estrutura qu?mica do pol?mero, for?a i?nica, massa molar e sua solubilidade no meio s?o respons?veis por afetar intrinsecamente a estabiliza??o das camadas da argila. Foram utilizadas no estudo tr?s amostras de carboximetilcelulose com diferentes massas molares e graus de substitui??o: CMC A (9 x 104 gmol DS 0.7), CMC B (2.5 x 105 gmol DS 0.7) e CMC C (2.5 x 105 gmol DS 1.2)) e tr?s amostras de calcita (CaCO3), com diferentes di?metros m?dios de part?culas e curvas de distribui??o em tamanho. O aumento do grau de substitui??o da CMC contribuiu para o aumento da densidade de carga do pol?mero e dessa forma, reduziu sua estabilidade em salmoura, promovendo agrega??o e o aumento do volume de filtrado. Por sua vez, o aumento da massa molar promoveu um aumento das propriedades reol?gicas com a redu??o do volume de filtrado. Ambos os efeitos est?o diretamente ligados ao volume hidrodin?mico da mol?cula do pol?mero no meio. A granulometria das part?culas do CaCO3 influenciou n?o somente as propriedades reol?gicas, devido ? adsor??o de pol?meros em sua superf?cie, mas tamb?m as propriedades de filtra??o. Foi observado que o menor volume de filtrado foi obtido pelo uso da amostra de CaCO3 de menor tamanho de part?cula com a faixa mais ampla de dispers?o em tamanho. Com rela??o ? inibi??o de inchamento de argilas, a efici?ncia da CMC foi comparada a outros produtos comumente empregados (cloreto de s?dio (NaCl), cloreto de pot?ssio (KCl) e um inibidor comercial ? base de amina quatern?ria). A CMC de baixa massa molar (9 x 104 g/mol) propiciou grau de inchamento da bentonita ligeiramente mais baixo que a CMC de alta massa molar (2.5 x 105 g/mol), no decorrer de 180 minutos. Por outro lado, p?de ser visualizado por microscopia eletr?nica de varredura que a CMC de maior massa molar (2.5 x 105 g/mol e DS 0.7) promoveu uma redu??o na forma??o e no tamanho dos poros da argila comparada ? CMC de menor massa molar (9.0 x 104 g/mol e DS 0.7), ap?s 1000 minutos em meio aquoso. Esse comportamento foi atribu?do ? din?mica das intera??es entre a argila e a cadeia polim?rica da CMC ao longo do tempo, que ? resultado da forte contribui??o das intera??es eletrost?ticas e liga??es de hidrog?nio entre os grupos carboxilato e hidroxila localizados ao longo da cadeia polim?rica e os s?tios i?nicos e polares da superf?cie da argila. A CMC adsorve na superf?cie da matriz de argila promovendo a forma??o de uma pel?cula , a qual ? respons?vel por minimizar a migra??o da ?gua para o meio poroso. Com o aumento do grau de substitui??o, foi observado aumento de poros na matriz de argila, sugerindo que a maior densidade de cargas no pol?mero diminui a sua flexibilidade e a adsor??o sobre a matriz argilosa. A an?lise conjunta dos resultados vi indica que altas massas molares da CMC propiciam melhores resultados no controle das propriedades reol?gicas, de filtra??o e de inchamento de argilas, entretanto, efeito contr?rio ? observado com o aumento do grau de substitui??o. Por sua vez, o CaCO3 apresenta melhores resultados de propriedades reol?gicas e de filtra??o com a diminui??o do di?metro m?dio das part?culas e aumento da distribui??o em tamanho. Em todas as propriedades analisadas, foram evidentes os sinais de intera??o da CMC com os minerais (carbonato de c?lcio e argila) presentes no meio aquoso
7

Filtra??o e invas?o de fluidos de perfura??o: estudo comparativo, caracteriza??o da torta e modelagem

CALABREZ, N?bya Dalvi 23 August 2013 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-11-12T17:56:54Z No. of bitstreams: 1 2013 - N?bya Dalvi Calabrez.pdf: 2204521 bytes, checksum: 71b05e242a3884d827606854f30c0359 (MD5) / Made available in DSpace on 2018-11-12T17:56:54Z (GMT). No. of bitstreams: 1 2013 - N?bya Dalvi Calabrez.pdf: 2204521 bytes, checksum: 71b05e242a3884d827606854f30c0359 (MD5) Previous issue date: 2013-08-23 / CAPES / Petrobras / Filtration and invasion of drilling fluids are phenomena that occur during the process of drilling oil wells. It is necessary to know the filter cake behavior, which is formed in order to prevent unwanted invasion of filtrate, which can cause irreversible damage for the reservoir rock, making impossible the well to produce oil. The goals of this work were: to study filtration and invasion of drilling fluids, under static and dynamic conditions, characterize the mudcake, obtain comparative results between different fluids (water base mud and emulsion) and model static filtration. For this, experiments were conducted in a high temperature/high pressure cell filtration, using filter paper as filter medium. The cake formed from the filtration of these fluids was characterized according to parameters such as porosity, permeability, compressibility, thickness, shear strength and friction factor. In a comparison between different fluids, it was observed that the water-based mud provided a mudcake more permeable and more porous than emulsion mudcake. Thus, water-based mud allowed more filtrate passed through the filter medium. The factors relevant to the estimation of the friction factor were determined. It was concluded that the compressibility index of the filter cake was a factor which had great influence on the estimation of this parameter. The model allowed the prediction of static filtration, slowness and mudcake thickness curves as a function of time. / A filtra??o e a invas?o de fluidos de perfura??o s?o fen?menos que ocorrem durante o processo de perfura??o de po?os de petr?leo. ? necess?rio conhecer como se comporta a torta de filtra??o formada a fim de evitar invas?es indesejadas do filtrado, o que pode causar danos muitas vezes irrevers?veis a rocha reservat?rio, tornando o po?o invi?vel para a produ??o do ?leo. Os objetivos desse trabalho foram: estudar os fen?menos de filtra??o e invas?o de fluidos de perfura??o base ?gua e emuls?o, sob condi??es est?ticas e din?micas, caracterizar a torta formada, obter resultados comparativos entre diferentes fluidos (base ?gua e emuls?o) e modelar a filtra??o est?tica. Para isso, foram conduzidos experimentos em uma c?lula de filtra??o high temperature/high presssure, utilizando papel de filtro como meio filtrante. A torta formada, a partir da filtra??o desses fluidos, foi caracterizada de acordo com par?metros como: porosidade, permeabilidade, compressibilidade, espessura, resist?ncia ao cisalhamento e fator de fric??o. Na compara??o entre os resultados experimentais para diferentes fluidos, observou-se que o fluido a base ?gua, por formar uma torta mais perme?vel e mais porosa, permitiu que mais filtrado passasse pelo meio filtrante, quando comparado ao fluido base ?leo (emuls?o). Foram estudados os fatores relevantes na estima??o do fator de fric??o da torta de filtra??o e concluiu-se que a compressibilidade da torta foi um fator que teve grande influ?ncia na estima??o desse par?metro. A modelagem da filtra??o est?tica possibilitou a previs?o do comportamento das curvas de filtra??o, de slowness e da espessura da torta em fun??o do tempo.
8

Desenvolvimento de membranas porosas de alumina para fins de tratamento de efluente industrial t?xtil / Development of porous alumina membranes for treatment of textile effluent

Souto, K?sia Karina de Oliveira 01 July 2013 (has links)
Made available in DSpace on 2014-12-17T14:07:17Z (GMT). No. of bitstreams: 1 KesiaKOS_TESE_PARCIAL.pdf: 625810 bytes, checksum: ba2f0bf53a4151666220c09ffd2f2947 (MD5) Previous issue date: 2013-07-01 / Textile production has been considered as an activity of high environmental impact due to the generation of large volumes of waste water with high load of organic compounds and strongly colored effluents, toxic and difficult biodegradability. This thesis deals with obtaining porous alumina ceramic membranes for filtration of textile effluent in the removal of contaminants, mainly color and turbidity. Two types of alumina with different particle sizes as a basis for the preparation of formulation for mass production of ceramic samples and membranes. The technological properties of the samples were evaluated after using sintering conditions: 1,350?C-2H, 1,450?C-30M, 1,450?C-2H, 1,475?C-30M and 1,475?C-2H. The sintered samples were characterized by XRD, XRF, AG, TG, DSC, DL, AA, MEA, RL, MRF-3P, SEM and Intrusion Porosimetry by Mercury. After the characterization, a standard membrane was selected with their respective sintering condition for the filterability tests. The effluent was provided by a local Textile Industry and characterized at the entry and exit of the treatment plant. A statistical analysis was used to study the effluent using the following parameters: pH, temperature, EC, SS, SD, oil and grease, turbidity, COD, DO, total phosphorus, chlorides, phenols, metals and fecal coliform. The filtered effluent was evaluated by using the same parameters. These results demonstrate that the feasibility of the use of porous alumina ceramic membranes for removing contaminants from textile effluent with improved average pore size of 0.4 micrometre (distribution range varying from 0,025 to 2.0 micrometre), with total porosity of 29.66%, and average percentages of color removal efficiency of 89.02%, 92.49% of SS, turbidity of 94.55%, metals 2.70% (manganese) to 71.52% (iron) according to each metal and COD removal of 72.80% / A produ??o t?xtil tem sido considerada uma atividade de alto impacto ambiental, devido ? gera??o de grandes volumes de rejeitos com alta carga de compostos org?nicos e efluente fortemente colorido, t?xico e dif?cil biodegradabilidade. O presente trabalho trata da obten??o de membranas cer?micas porosas de alumina para filtra??o de efluente industrial t?xtil na remo??o de contaminantes, em especial, cor e turbidez. Utilizou-se dois tipos de alumina com granulometrias diferentes como base para o preparo de formula??es de massas cer?micas para a produ??o dos corpos de prova e membranas. As propriedades tecnol?gicas dos corpos de prova foram avaliadas ap?s suas sinteriza??es nas condi??es de: 1.350?C 2H, 1.450?C 30M, 1.450?C 2H, 1.475?C 30 M e 1.475?C 2H. Foram caracterizadas por DRX, FRX, AG, TG, DSC, DL, AA, MEA, RL, MRF-3P, MEV e Porosimetria por Intrus?o de Merc?rio. Ap?s essa caracteriza??o definiu-se uma membrana padr?o, com a sua respectiva condi??o de sinteriza??o, para os ensaios de filtrabilidade. O efluente foi fornecido por uma Ind?stria t?xtil do RN, e caracterizado nos pontos de entrada e sa?da da ETE. Utilizou-se um tratamento estat?stico dos resultados analisados no efluente atrav?s dos seguintes par?metros: pH, temperatura, CE, SS, SD, ?leos e graxas, turbidez, DQO, OD, f?sforo total, cloretos, fen?is, metais e coliformes termotolerantes. O permeado (EF) foi avaliado pelos mesmos par?metros. Os resultados obtidos demonstram a viabilidade no uso de membranas cer?micas porosas de alumina na remo??o de contaminantes de efluente industrial t?xtil, com melhor tamanho m?dio de poro de 0,4?m (faixa de distribui??o de tamanhos de poros variando de 0,025 a 2 ?m), com porosidade total de 29,66%, com percentuais m?dios de efici?ncia na remo??o de cor de 89,02%, SS de 92,49%, turbidez de 94,55%, metais variando de 2,70% (mangan?s) at? 71,52% (ferro) de acordo com cada metal e remo??o de DQO de 72,80% / 2020-01-01
9

Modelagem matem?tica e experimental da perda de injetividade em po?os canhoneados

Gomes, Vanessa Limeira Azevedo 20 November 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-06-10T19:20:11Z No. of bitstreams: 1 VanessaLimeiraAzevedoGomes_TESE.pdf: 3568027 bytes, checksum: 5b81da1eba84c90799bbf4cc69a3c6c1 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-13T20:36:35Z (GMT) No. of bitstreams: 1 VanessaLimeiraAzevedoGomes_TESE.pdf: 3568027 bytes, checksum: 5b81da1eba84c90799bbf4cc69a3c6c1 (MD5) / Made available in DSpace on 2016-06-13T20:36:35Z (GMT). No. of bitstreams: 1 VanessaLimeiraAzevedoGomes_TESE.pdf: 3568027 bytes, checksum: 5b81da1eba84c90799bbf4cc69a3c6c1 (MD5) Previous issue date: 2015-11-20 / Ag?ncia Nacional do Petr?leo - ANP / A inje??o de ?gua em reservat?rios de petr?leo ? uma t?cnica de recupera??o amplamente utilizada para a recupera??o de ?leo. No entanto, a ?gua injetada cont?m part?culas suspensas que podem ser retidas, causando dano ? forma??o e perda de injetividade. Nesses casos, ? necess?rio estimular a forma??o danificada com o intuito de restaurar a injetividade dos po?os injetores. A perda de injetividade causa um grande impacto negativo ? economia de produ??o de petr?leo e, por isso, prever a injetividade ? importante para o gerenciamento de projetos de inje??o de ?gua. Modelos matem?ticos para perda de injetividade permitem estudar o efeito da qualidade da ?gua injetada bem como das caracter?sticas do po?o e da forma??o. Dessa forma, foi desenvolvido um modelo matem?tico da perda de injetividade para po?os injetores canhoneados. A novidade cient?fica deste trabalho refere-se ? modelagem e previs?o da perda de injetividade em po?os canhoneados injetores, considerando a filtra??o profunda e forma??o do reboco externo em canhoneados esferoidais. A modelagem cl?ssica para a filtra??o profunda foi reescrita em coordenadas esferoidais. A solu??o para a concentra??o de part?culas em suspens?o foi obtida analiticamente e a concentra??o de part?culas retidas, que causam dano ? forma??o, foi resolvida numericamente. Considerando uma vaz?o injetada constante e utilizando a lei de Darcy modificada, estimamos a imped?ncia, definida como sendo o inverso da injetividade normalizada pelo inverso da injetividade inicial. Finalmente, foram realizados testes de injetividade cl?ssicos para fluxo linear, em amostras de Arenito Berea, e tamb?m em amostras "canhoneadas". Os par?metros do modelo, coeficientes de filtra??o e de dano ? forma??o, obtidos a partir do tratamento dos dados, foram utilizados para a verifica??o da modelagem proposta. As simula??es mostraram um bom ajuste aos dados experimentais, sendo observado que a raz?o entre o tamanho das part?culas e dos poros tem grande influ?ncia no comportamento da perda de injetividade. / Water injection in oil reservoirs is a recovery technique widely used for oil recovery. However, the injected water contains suspended particles that can be trapped, causing formation damage and injectivity decline. In such cases, it is necessary to stimulate the damaged formation looking forward to restore the injectivity of the injection wells. Injectivity decline causes a major negative impact to the economy of oil production, which is why, it is important to foresee the injectivity behavior for a good waterflooding management project. Mathematical models for injectivity losses allow studying the effect of the injected water quality, also the well and formation characteristics. Therefore, a mathematical model of injectivity losses for perforated injection wells was developed. The scientific novelty of this work relates to the modeling and prediction of injectivity decline in perforated injection wells, considering deep filtration and the formation of external cake in spheroidal perforations. The classic modeling for deep filtration was rewritten using spheroidal coordinates. The solution to the concentration of suspended particles was obtained analytically and the concentration of the retained particles, which cause formation damage, was solved numerically. The acquisition of the solution to impedance assumed a constant injection rate and the modified Darcy?s Law, defined as being the inverse of the normalized injectivity by the inverse of the initial injectivity. Finally, classic linear flow injectivity tests were performed within Berea sandstone samples, and within perforated samples. The parameters of the model, filtration and formation damage coefficients, obtained from the data, were used to verify the proposed modeling. The simulations showed a good fit to the experimental data, it was observed that the ratio between the particle size and pore has a large influence on the behavior of injectivity decline.
10

Influ?ncia da press?o e da vaz?o de concentrado sobre o desempenho de ultrafiltra??o no p?s-tratamento de esgotos

Barros Filho, Marcos Andr? Capitulino de 14 December 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-06-23T20:18:47Z No. of bitstreams: 1 MarcosAndreCapitulinoDeBarrosFilho_DISSERT.pdf: 1391023 bytes, checksum: c9de84ee4fe7550a9fa173f8a04d4002 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-27T21:06:25Z (GMT) No. of bitstreams: 1 MarcosAndreCapitulinoDeBarrosFilho_DISSERT.pdf: 1391023 bytes, checksum: c9de84ee4fe7550a9fa173f8a04d4002 (MD5) / Made available in DSpace on 2016-06-27T21:06:25Z (GMT). No. of bitstreams: 1 MarcosAndreCapitulinoDeBarrosFilho_DISSERT.pdf: 1391023 bytes, checksum: c9de84ee4fe7550a9fa173f8a04d4002 (MD5) Previous issue date: 2015-12-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Apesar das in?meras vantagens advindas do uso da tecnologia de membranas filtrantes, algumas limita??es inerentes ao processo de incrusta??o tornam-se relevantes para sua aplicabilidade. O controle das condi??es operacionais consiste em importante ferramenta para mitigar o fouling e alcan?ar bons n?veis de efici?ncia. Nesse sentido, o objetivo deste trabalho foi investigar o efeito da press?o transmembrana e da vaz?o de concentrado no desempenho da ultrafiltra??o, aplicada ao p?s-tratamento de esgoto sanit?rio. O processo foi avaliado e otimizado variando-se a press?o (0,5 e 1,5 bar) e a vaz?o de concentrado (300 e 600 L/h), por meio de um planejamento fatorial 22, a fim de investigar os efeitos no fluxo permeado e na qualidade dos efluentes gerados, em cada condi??o operacional. Avaliaram-se os seguintes indicadores de qualidade para os permeados: pH, Condutividade El?trica, S?lidos Suspensos Totais, Turbidez, C?lcio e Demanda Qu?mica de Oxig?nio (DQO). Em todos os ensaios, observou-se diminui??o acentuada do fluxo permeado nos instantes iniciais, seguida de uma queda lenta que se prolongou at? atingir um patamar relativamente constante por volta dos 120 minutos de filtra??o. O aumento da press?o resultou em maior fluxo permeado inicial, por?m a queda do fluxo com o tempo foi maior para os ensaios realizados a press?o mais elevada, evidenciando um processo de incrusta??o mais pronunciado. Por outro lado, o aumento da vaz?o de concentrado resultou em queda mais lenta de fluxo permeado com o tempo de filtra??o. Com rela??o a qualidade dos permeados, a press?o transmembrana de 0,5 bar foi a que permitiu melhores resultados, sendo confirmado estatisticamente, por meio do teste da ANOVA two-way com medidas repetidas, efeito significativo da press?o sobre a turbidez do permeado. A vaz?o de concentrado, por sua vez, n?o apresentou influ?ncia significativa sobre nenhum dos par?metros de qualidade. Dessa forma, considerando que o efeito do aumento da vaz?o de concentrado no retardamento do fouling n?o resultou em melhoria significativa do fluxo permeado, conclui-se que a condi??o operacional otimizada para a gera??o de permeados com maior grau de pureza, associado a gera??o de um menor volume de res?duo, consiste naquela em que se aplica uma press?o transmembrana baixa associada a uma vaz?o menor de concentrado. / Despite the numerous advantages resulting from the use of membrane filters technology, intrinsic limitations fouling process become relevant to its applicability. The control of operating conditions is an important tool to mitigate fouling and achieve good levels of efficiency. In this sense, the objective of this study was to investigate the effect of transmembrane pressure and concentrate flow in the performance of ultrafiltration, applied to the post-treatment of domestic sewage. The process was evaluated and optimized by varying the pressure (0.5 and 1.5 bar) and the concentrate flow (300 and 600 L/h), using a 22 factorial design, in order to investigate the effects on the permeate flow and quality of effluents generated at each operating condition. We evaluated the following quality indicators for permeate: pH, electrical conductivity, total suspended solids, turbidity, calcium and Chemical Oxygen Demand (COD). In all tests, we observed marked reduction in the permeate flux at the early stages, followed by a slow decline that lasted until it reaches a relatively constant level, around 120 minutes of filtration. The increased pressure resulted in a higher initial permeate flux, but the decrease of the flow with time is greater for tests at higher pressure, indicating a more pronounced fouling process. On the other hand, increasing the concentrate flow resulted in a slower decline in permeate flux with the filtration time. Regarding the quality of permeate, the transmembrane pressure of 0,5 bar was the one that allowed better results, and was statistically confirmed through the two-way ANOVA test with repeated measures, significant effect of pressure on the turbidity of the permeate. The concentrate flow, in turn, showed no significant influence on any of the quality parameters. Thus, we conclude that, from an economic and environmental point of view, it is more interesting to operate ultrafiltration membrane system with a lower concentrate flow associated with a low transmembrane pressure, since under these conditions will produce less waste, and the permeate will present lower concentrations of the analyzed constituent, especially lower turbidity.

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