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Avalia??o de floculante natural ? base de Moringa oleifera no tratamento de ?gua produzida na ind?stria do petr?leo: aplica??o da t?cnica combinada flocula??o/flota??o / Assess the natural flocculent based on Moringa oleifera in the treatment of the produced water in the oil industry: employment of the flocculating-flotation combined technicalMagalh?es, Emilianny Rafaely Batista 30 July 2014 (has links)
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Previous issue date: 2014-07-30 / O principal efluente presente na ind?stria do petr?leo ? a ?gua produzida, que normalmente est? associada ao ?leo produzido, apresentando um consider?vel volume de produ??o e podendo refletir em efeitos nocivos ao meio ambiente e ? sociedade caso seu descarte seja inadequado, sendo imprescind?vel, portanto, um valoroso cuidado para estabelecer e manter a sua gest?o. O tratamento convencional para este efluente associa as t?cnicas de flocula??o e flota??o. Na flocula??o s?o utilizados floculantes convencionais que, al?m do alto custo, s?o fornecidos com pouca informa??o t?cnica. A flota??o ? a etapa na qual ? poss?vel obter a separa??o das part?culas coloidais presentes no efluente, sendo a flota??o por ar dissolvido (FAD) uma t?cnica que vem se consolidando economicamente e apresentantdo grande confiabilidade ambiental ao se comparar com outros processos. A FAD se apresenta como um processo largamente empregado em v?rios campos de tratamento de ?guas de abastecimento e de efluentes industriais em todo o planeta. Neste sentido, esse trabalho objetivou avaliar o potencial de um floculante alternativo natural ? base de Moringa oleifera na redu??o do teor de ?leos e graxas (TOG) da ?gua produzida na ind?stria do petr?leo atrav?s do m?todo de flocula??o/FAD. Avaliou-se a efici?ncia do floculante natural e se comparou sua efici?ncia com dois floculantes comerciais normalmente utilizados pela ind?stria do petr?leo (A e B). Os resultados de efici?ncias globais para todos os floculantes foram tratados atrav?s de planejamentos estat?sticos experimentais com base na utiliza??o do software STATISTICA vers?o 10.0. Obteve-se no planejamento experimental superf?cies de contorno e de resposta que foram interpretadas em termos da vari?vel resposta efici?ncia de remo??o de TOG (Teor de ?leos e/ou Graxas). O planejamento permitiu ainda a obten??o de modelos matem?ticos para c?lculo da vari?vel resposta nas condi??es estudadas. Os floculantes comerciais A e B apresentaram comportamentos similares, com efici?ncia global m?dia de 90% na efici?ncia de remo??o do ?leo, sendo a an?lise econ?mica o fator decisivo para a escolha de utiliza??o desses floculantes no processo. O floculante alternativo natural, ? base de Moringa oleifera, apresentou menor efici?ncia de separa??o que ?quelas de A e B (em m?dia 70%), por outro lado este floculante se apresenta ambientalmente correto e de menor custo. / The principal effluent in the oil industry is the produced water, which is commonly
associated to the produced oil. It presents a pronounced volume of production and it can be
reflected on the environment and society, if its discharge is unappropriated. Therefore, it is
indispensable a valuable careful to establish and maintain its management. The traditional
treatment of produced water, usualy includes both tecniques, flocculation and flotation. At
flocculation processes, there are traditional floculant agents that aren?t well specified by
tecnichal information tables and still expensive. As for the flotation process, it?s the step in
which is possible to separate the suspended particles in the effluent. The dissolved air
flotation (DAF) is a technique that has been consolidating economically and environmentally,
presenting great reliability when compared with other processes. The DAF is presented as a
process widely used in various fields of water and wastewater treatment around the globe. In
this regard, this study was aimed to evaluate the potential of an alternative natural flocculant
agent based on Moringa oleifera to reduce the amount of oil and grease (TOG) in produced
water from the oil industry by the method of flocculation/DAF. the natural flocculant agent
was evaluated by its efficacy, as well as its efficiency when compared with two commercial
flocculant agents normally used by the petroleum industry. The experiments were conducted
following an experimental design and the overall efficiencies for all flocculants were treated
through statistical calculation based on the use of STATISTICA software version 10.0.
Therefore, contour surfaces were obtained from the experimental design and were interpreted
in terms of the response variable removal efficiency TOG (total oil and greases). The plan still
allowed to obtain mathematical models for calculating the response variable in the studied
conditions. Commercial flocculants showed similar behavior, with an average overall
efficiency of 90% for oil removal, however it is the economical analysis the decisive factor to
choose one of these flocculant agents to the process. The natural alternative flocculant agent
based on Moringa oleifera showed lower separation efficiency than those of commercials one
(average 70%), on the other hand this flocculant causes less environmental impacts and it?s
less expensive
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Tratamento de ?gua produzida utilizando a t?cnica combinada flocula??o/flota??o por ar dissolvido com mistura de polieletr?litos e moringa ole?fera / Treatment of produced water using combined technique flocculation/dissolved air flotation with the mix of polyelectrolyte and moringa ole?feraFreitas, J?ssica Isabelle de Souza 29 July 2016 (has links)
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Previous issue date: 2016-07-29 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / A ind?stria de petr?leo ? um dos setores com maior potencial de degrada??o ambiental, sendo a ?gua produzida o res?duo mais relevante. A complexa composi??o qu?mica e o elevado volume gerado deste efluente exigem um rigoroso controle e gerenciamento. Assim, antes de ser descartada, reinjetada em po?os ou para outra finalidade esta ?gua deve ser tratada de acordo com a legisla??o ambiental vigente. No que se refere ao tratamento de ?gua produzida para remo??o do teor de ?leos e graxas, a t?cnica combinada flocula??o/flota??o por ar dissolvido vem sendo bastante estudada. Na etapa de flocula??o vem sendo utilizado floculantes qu?micos convencionais de elevado custo e n?o-biodegrad?veis. Nesse contexto, avaliou-se a efici?ncia de remo??o do teor de ?leos e graxas da ?gua produzida atrav?s da t?cnica combinada flocula??o/flota??o por ar dissolvido utilizando a mistura de floculantes natural de Moringa ole?fera e dois floculantes comerciais ?C? e ?D? (j? utilizados na ind?stria), objetivando deixar a ?gua produzida nas condi??es de descarte. Os ensaios foram realizados segundo planejamento experimental para avalia??o estat?stica da influ?ncia da concentra??o total de floculante, tempo de mistura lenta e tempo de flota??o na efici?ncia de remo??o do teor de ?leos e graxas. Al?m disso, para cada mistura e suas respectivas propor??es estudadas, obtiveram-se modelos matem?ticos. O tratamento do efluente utilizando a mistura do floculante Moringa ole?fera e floculante comercial ?D?, com propor??o de mistura em base volum?trica 50:50%, atendeu os requisitos ambientais em todas as condi??es avaliadas; enquanto, nas mesmas condi??es, n?o foi poss?vel utilizando a mistura do floculante Moringa ole?fera e floculante comercial ?C?. Tamb?m verificou-se a efici?ncia de remo??o de ?leos e graxas com mistura do floculante Moringa ole?fera e floculante comercial ?D? com propor??o de mistura em base volum?trica 70:30% (respectivamente) sendo esta condi??o de interesse ambiental, uma vez que foi poss?vel atender os requisitos ambientais para descarte da ?gua produzida. Todas as misturas do floculante de Moringa ole?fera e floculantes comerciais ?C? e ?D? estudadas mostraram-se eficazes na adequa??o da ?gua produzida para descarte. Finalmente, avaliou-se o efeito potencializador da Moringa ole?fera sobre o floculante comercial ?D? na remo??o do teor de ?leos e graxas da ?gua produzida. / The Oil Industry is one of the sectors with greatest potential for environmental degradation and the produced water is the largest waste stream generated in this industry. The complex chemical composition and the high volume generated of this effluent hold a strict control and management. In accordance with current environmental legislation the water should be treated before final disposal, reuse or recycle including underground injected vapor to increase oil production. In view of the treatment of produced water for oil and grease content removal, the combined technique flocculation/dissolved air flotation has been extensively studied. In the flocculation step has been used high cost flocculants of chemical industry which are non-biodegradable. In this context it was evaluated the removal efficiency of oil and grease content from produced water by the combined technique flocculation/dissolved air flotation using Moringa Ole?iferaM.O) a natural flocculant blended with two commercial flocculants ?C? and ?D? (currently used in the oil industry), aiming to let the water produced in the disposal conditions. The experiments were conducted by means of statistical experimental design evaluating the influence of the total concentration of flocculants, slow mixing time and flotation time over the efficiency of oil and grease content removal. Moreover, for each mixture and their respective ratios studied, were obtained mathematical models. The effluent treatment using the mixture of Moringa ole?fera and commercial ?D? flocculants with mixing ratio of 50:50 (%, volume basis) achieved the environmental requirements in all conditions evaluated, while, under the same conditions it wasn?t possible using the mixture of Moringa Ole?fera and commercial ?C? flocculant. The oil and grease removal content efficiency using a mixing ratio of 70:30 (%, volume basis of M. O and commercial flocculant, respectively) showed to be an interesting condition to reach the environmental requirements for produced water disposal once all mixtures of Moringa Ole?fera and commercial flocculants ?C? and ?D? achieved satisfactory experimental results for produced water disposal. Finally, we evaluated the effect of improvement of Moringa ole?fera into commercial flocculant ?D? on oil and grease removal content efficiency.
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Flota??o por ar dissolvido como p?s-tratamento de efluentes de lagoas de estabiliza??oBrito, Andr? C?mara de 08 July 2016 (has links)
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Previous issue date: 2016-07-08 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Para tratamento de esgotos dom?sticos lagoas de estabiliza??o possuem importantes vantagens, como elevada efici?ncia na remo??o de mat?ria org?nica e organismos patog?nicos, n?o utiliza??o de energia el?trica e facilidade operacional, principalmente em regi?es de clima tropical. Por outro lado, uma de suas desvantagens ? a elevada concentra??o de s?lidos suspensos, principalmente devido a biomassa algal. O objetivo desta pesquisa foi avaliar a efici?ncia de remo??o da flota??o por ar dissolvido (FAD) no p?s-tratamento de efluentes de lagoas de estabiliza??o. Para os ensaios com a FAD (coagula??o-flocula??o-flota??o) foi utilizado um flotateste de bancada. Foi planejado um delineamento experimental tipo fatorial aleat?rio, utilizando o crit?rio ka-1, em que k ? o n?mero de n?veis (k=3: menor, central, maior) e a ? o n?mero de fatores (a=4: dose de coagulante, taxa de recircula??o de ?gua saturada, pH e tempo de flocula??o), com ensaios realizados em triplicata, para os coagulantes policloreto de alum?nio e cloreto f?rrico em efluente de lagoas de facultativa prim?ria e lagoa de matura??o. As amostras do efluente da lagoa facultativa e efluente final da ETE Ponta Negra (Natal) foram coletadas semanalmente, no per?odo da manh?. As seguintes vari?veis foram avaliadas nos efluentes brutos e ap?s os ensaios com FAD: turbidez, s?lidos suspensos totais, cor aparente, DQO, clorofila ?a?, fosforo total, ortofosfato sol?vel e nitrog?nio amoniacal e org?nico. A vari?vel operacional com maior influ?ncia na remo??o as vari?veis avaliadas foi a dose de coagulante para o coagulante PAC e para o coagulante cloreto f?rrico a maior influ?ncia na remo??o das vari?veis foi o pH seguido da dosagem de coagulante. A partir da dosagem otimizada as remo??es nos par?metros analisados atingiram valores entre 66% e 97%. O p?s-tratamento na lagoa facultativa obteve o maior percentual de remo??o nas vari?veis analisadas para os dois coagulantes, assim como o cloreto f?rrico obtive maiores percentuais de remo??o em todas as situa??es. / For treatment of wastewater stabilization ponds have important advantages, such as high efficiency in removing organic matter and pathogens, non-use of electricity and operational ease, especially in tropical regions. On the other hand, one of its disadvantages is the high concentration of suspended solids, mostly due to algal biomass. The objective of this research was to evaluate the removal efficiency flotation by dissolved air (FAD) in the post-treatment stabilization ponds effluent. For tests with the FAD (coagulation-flocculation-flotation) we used a bench flotateste. a random factorial experimental design was planned using the ka-1 criterion, where k is the number of levels (k = 3: low, middle, major) and a is the number of factors (a = 4: coagulant dose saturated, water recirculation rate, pH and flocculation time) with assays performed in triplicate for the coagulant polyaluminium chloride, ferric chloride effluent primary facultative lagoons and maturation pond. Samples of the effluent from the facultative pond and final effluent from the WWTP Ponta Negra (Natal) were collected weekly in the morning. The following variables were evaluated in the raw wastewater and after the tests with FAD: turbidity, total suspended solids, apparent color, COD, chlorophyll "a", total phosphorus, orthophosphate soluble and ammonia and organic nitrogen. The operational variable with higher influence on the removal variables was evaluated coagulant dose for the PAC coagulant and the coagulant ferric chloride to remove the greatest influence variable was the pH followed by coagulant dosage. From the optimized dosage removals in the analyzed parameters reached values between 66% and 97%. The post-treatment in the facultative pond had the highest percentage removal in variables for the two coagulants, and ferric chloride got higher removal percentages in all situations.
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Flota??o por ar dissolvido para os minerais quartzo e feldspato utilizando coletores cati?nicosBarbalho, Bruno Castro 04 May 2012 (has links)
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Previous issue date: 2012-05-04 / The pegmatite rocks in Rio Grande do Norte are responsible for much of the production of industrial minerals like quartz and feldspar. Quartz and feldspar are minerals from pegmatite which may occur in pockets with metric to centimetric dimensions or as millimetric to sub millimetric intergrowths. The correct physical liberation of the mineral of interest, in case of intergrowths, requires an appropriate particle size, acquired by size reduction operations. The method for treating mineral which has a high efficiency fines particles recovery is flotation. The main purpose of the present study is to evaluate the recovery of quartz and potassium feldspar using cationic diamine and quaternary ammonium salt as collectors by means of dissolved air flotation DAF. The tests were performed based on a central composite design 24, by which the influence of process variables was statistically verified: concentration of the quaternary ammonium salt and diamine collectors, pH and conditioning time. The efficiency of flotation was calculated from the removal of turbidity of the solution. Results of maximum flotation efficiency (60%) were found in the level curves, plotted in conditions of low concentrations of collectors (1,0 x 10-5 mol.L-1). These high flotation efficiencies were obtained when operating at pH 4 to 8 with conditioning time ranging from 3 to 5 minutes. Thus, the results showed that the process variables have played important roles in the dissolved air flotation process concerning the flotability of the minerals. / No Rio Grande do Norte os pegmatitos respondem por grande parte da produ??o dos minerais industriais quartzo e feldspato. O quartzo e feldspato dos pegmatitos podem ocorrer em bols?es com dimens?es centim?tricas a m?tricas ou na forma de intercrescimentos milim?tricos a submilim?tricos. No caso dos intercrescimentos, a libera??o f?sica correta do mineral de interesse envolve a adequa??o granulom?trica atrav?s de opera??es de redu??o de tamanho. O m?todo no tratamento mineral que apresenta alta efici?ncia na recupera??o de finos ? a flota??o. O presente trabalho tem como objetivo principal avaliar a recupera??o de quartzo e feldspato pot?ssico utilizando os coletores cati?nicos diamina e sal quatern?rio de am?nio no processo de flota??o por ar dissolvido FAD. Os testes foram realizados baseados em um planejamento central composto 24, atrav?s do qual verificou-se estatisticamente a influ?ncia das vari?veis de processo: concentra??o dos coletores sal quatern?rio de am?nio e diamina, pH e tempo de condicionamento. A efici?ncia de flota??o foi calculada a partir do grau de remo??o de turbidez da solu??o. Resultados de m?xima efici?ncia de flota??o (60%) foram encontrados nas curvas de n?vel, plotadas nas condi??es de baixas concentra??es dos coletores (1,0x10-5 mol.L-1). Estas altas efici?ncias de flota??o foram obtidas operando-se na faixa de pH 4 8 com tempo de condicionamento variando de 3 a 5 minutos. Sendo assim, os resultados obtidos mostraram que as vari?veis de processo desempenharam pap?is importantes no processo de flota??o por ar dissolvido em rela??o ? flotabilidade dos minerais.
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Separa??o de cristais de estruvita de percolado de lodo por flota??o por ar dissolvidoSilva, Lorena Albuquerque Adriano da 06 September 2013 (has links)
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Previous issue date: 2013-09-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The struvite precipitation in wastewater treatments plants offer advantages to obtaining a economically viable product, containing phosphorus, nitrogen and magnesium, in a bioavailable conditions to plants. The precipitation process requires ideal conditions, but all of these aspects are difficult to obtain and may result in resistance to collect crystals during the sedimentation process. Therefore, instead find the best conditions for precipitation, we propose the dissolved air flotation as another method to retrieve the crystals. The application of dissolved air flotation method to promote separation of struvite crystals from sewage supernatant, was evaluated in a precipitation-flotation reactor (flotatest) and were compared with the precipitation-sedimentation assays (jar test). Finally, were observed that the dissolved air flotation process was as feasible as sedimentation to promote struvite crystals separation, and the pH are the most influencer factor for an efficient separation / A precipita??o de estruvita em Esta??es de Tratamento de Esgoto oferece como vantagem a obten??o de um produto economicamente vi?vel, com f?sforo, nitrog?nio e magn?sio em sua composi??o e biologicamente dispon?vel para as plantas. Este processo necessita de condi??es ideais para que ocorra a precipita??o, por?m a dificuldade de atingir tais condi??es pode resultar em resist?ncia na coleta de cristais durante o processo de sedimenta??o. Assim, em vez de buscar as melhores condi??es de precipita??o, que em muitos casos n?o podem ser atingidas, propomos utilizar a flota??o por ar dissolvido (FAD) como uma alternativa ? sedimenta??o de part?culas. A avalia??o da aplicabilidade do processo de Flota??o por Ar Dissolvido (FAD) na separa??o de cristais de estruvita em percolado de lodo foi realizada em reator de precipita??o-flota??o (flotateste) e comparada com ensaios de precipita??o-sedimenta??o (jar teste). Por fim, foi observado que a flota??o por ar dissolvido ? vi?vel na separa??o de cristais de estruvita tanto quanto a sedimenta??o, sendo o pH o fator que exerceu maior influ?ncia sobre a efici?ncia de separa??o
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Flota??o por ar dissolvido na clarifica??o de ?guas com baixa turbidez utilizando sulfato de alum?nio e sementes de Moringa oleifera como coagulantes / Dissolved air Flotation , for clarifying water with low turbidity using aluminum sulphate and Moringa oleifera seeds as coagulantsL?do, Patr?cia Guilhermina da Silva 22 December 2008 (has links)
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Previous issue date: 2008-12-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work aims to investigate the process of Dissolved air Flotation (DAF) for clarifying water samples with low turbidity using aluminum sulphate and Moringa oleifera seeds as coagulants. The experimental procedure was carried out in a bench scale flotation unit. The influences on the pre-treatment conditions (coagulant dosage and flocculation time) and flotation parameters (superficial application rate and recirculation rate) were evaluated considering the efficiency of the process. The efficiency was evaluated by determining the turbidity of the untreated and treated water samples. The results obtained showed that turbidity reduction can be obtained very efficiently by using DAF and the latter coagulant in low turbidity water. Using aluminum sulphate in pH?s 5.0 and 6.0 better efficiencies were obtained with low concentrations (15 mg/L), achieving values of 92% of turbidity reduction. In the case of use of Moringa oleifera better efficiencies of reduction of turbidity were reported when using a concentration of 50 mg/L in all range of pH?s, achieving 86% of reduction. The zeta potential was also determined, in an attempt to aid comprehension of the coagulation mechanisms involved. The coagulation mechanisms with Moringa oleifera seeds were shown to be adsorption and charge neutralization, as well as adsorption and bridging. Concerning aluminum sulphate, the predominant mechanisms are adsorption and charge neutralization and enmeshment in a precipitate. The results indicate that for low turbidity water, Moringa oleifera seeds could potentially be a viable substitute for aluminum sulphate / O presente trabalho tem como objetivo investigar o processo da flota??o por ar dissolvido sob press?o - FAD para clarifica??o de ?guas com baixa turbidez utilizando sulfato de alum?nio e sementes de Moringa oleifera como coagulantes. O procedimento experimental foi realizado em uma unidade de flota??o em escala de bancada. Foram avaliadas as influ?ncias das condi??es do pr?-tratamento (dosagem de coagulante e tempo de flocula??o) e par?metros de processo da flota??o (taxa de aplica??o superficial e taxa de recircula??o) na efici?ncia do processo. A efici?ncia foi avaliada pela determina??o de turbidez nas amostras de ?gua bruta e tratada. Os resultados obtidos mostraram que elevadas efici?ncias de redu??o da turbidez podem ser conseguidas com o uso da FAD em ?guas com baixa turbidez utilizando estes coagulantes. Para o sulfato de alum?nio, nos pHs 5,0 e 6,0 as melhores efici?ncias foram alcan?adas com baixas dosagens (15 mg/L), alcan?ando valores de at? 92% de redu??o. Para a Moringa oleifera, as melhores efici?ncias de redu??o de turbidez foram ? dosagem aproximada de 50 mg/L para todos os pHs, alcan?ando valores de 86% de redu??o. Determinou-se tamb?m o potencial zeta, com o objetivo de auxiliar na compreens?o dos mecanismos envolvidos na coagula??o. Os mecanismos de coagula??o com sementes de Moringa oleifera indicam ser adsor??o e neutraliza??o de cargas e adsor??o e forma??o de pontes. No que diz respeito ao sulfato de alum?nio os mecanismos predominantes s?o adsor??o e neutraliza??o de cargas e varredura. Os resultados indicam que para ?guas de baixa turbidez, as sementes de Moringa oleifera podem ser um substituto potencialmente vi?vel em rela??o ao sulfato de alum?nio
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