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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.
61

Aplica??o da parafina e do ?leo de linha?a como hidrofobizantes da vermiculita, para remo??o de derivados de ?leo diesel resentes em ?gua produzida sint?tica

Santos, Aline da Silva 29 October 2010 (has links)
Made available in DSpace on 2014-12-17T15:41:57Z (GMT). No. of bitstreams: 1 AlineSS_DISSERT.pdf: 1736350 bytes, checksum: c0d8fc169a3fee522a620adb1ae979a1 (MD5) Previous issue date: 2010-10-29 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Produced water has lately aroused interest due to their high degree of salinity, suspended oil particles, chemicals added in various manufacturing processes, heavy metals and radioactivity sometimes. Along with oil and due to its high volume production, water production is one of the pollutants of most concern in the process of oil extraction. PAHs due to their ubiquity and their characteristics carcinogenic or mutagenic and teratogenic even have attracted the attention of every scientific society. Formed from the incomplete combustion of organic matter may be natural or anthropogenic. Some materials have been researched with the goal of cleaning up environmental matrices that may be contaminated by hydrocarbons. Among these materials researched various clays have been employed, of which highlights the vermiculite. The family of phyllosilicates, vermiculite for its potential and its high hydrophobic surface area has been a tool widely used in the decontamination of water in processes of oil spills. However, when it loses its capacity expanded hydrophobic having the necessity of using a hidrofobizante to make it organophilic. Among the numerous hidrofobizantes researched and used the linseed oil was the pioneer. In this study sought to evaluate the capacity of removal of PAHs using the vermiculite hydrofobized with linseed oil and wax also, for it was made use of the 24 full factorial design as the main tool for the experiments. We also evaluated the clay grain size (-20 +48 and -48 +80 #), the percentage of hidrofobizante applied (5 and 10%) and salinity of the water produced synthesized in our laboratory (35,000 and 55,000 ppm). The molecular fluorescence spectroscopy due to its sensitivity and speed was used to verify the adsorption capacity of clay, as well as gas chromatography served as an auxiliary technique to identify and quantify the PAHs in solution. In order to characterize the vermiculite was made use of X-ray fluorescence and X-ray diffraction. The infrared and thermogravimetry were essential to note hydrophobization and the amount of coating of clay. According to the fluorescence analysis showed that the test 12 was the best result in about 98% adsorption of fluorescent compounds, however the high salinity, the smallest particle size, the highest percentage of hidrofobizante and the use of linseed oil showed greater efficiency in the removal capacity of these hydrocarbons, in accordance with the trend followed by the analysis of the major factors of the factorial design. To verify the adsorption capacity of clay using a fixed volume of water produced synthetically, used as the test base 12, at their respective levels and factors. Thus, it was observed that after adding about 1 ? liters of water solution produced synthetically, about 300 times its volume in mass, the vermiculite was able to adsorb 80% of fluorescent species present in solution / A ?gua produzida vem ultimamente despertando interesse devido ao seu elevado grau de salinidade, part?culas de ?leo em suspens?o, produtos qu?micos adicionados nos diversos processos de produ??o, metais pesados e algumas vezes radioatividade. Juntamente com o petr?leo e devido ao seu elevado volume de produ??o, a ?gua de produ??o ? um dos poluentes que mais preocupam no processo de extra??o do ?leo. Os HPAs devido a sua ubiq?idade e suas caracter?sticas carcinog?nicas/mutag?nicas e at? mesmo teratog?nicas v?m chamando a aten??o de toda sociedade cient?fica. Formados a partir da combust?o incompleta da mat?ria org?nica podem ser de origem natural ou antropog?nica. Alguns materiais v?m sendo pesquisados com o objetivo de despoluir matrizes ambientais que venham ser contaminadas por estes hidrocarbonetos. Dentre estes materiais pesquisados v?rias argilas t?m sido empregadas, das quais se destaca a vermiculita. Da fam?lia dos filossilicatos, a vermiculita por seu potencial hidrof?bico e sua elevada ?rea superficial tem sido um utens?lio bastante utilizado na descontamina??o de ?guas em processos de derramamento de ?leo. Contudo, quando expandida esta perde sua capacidade hidrof?bica havendo a necessidade do uso de um hidrofobizante para torn?-la organof?lica. Dentre os in?meros hidrofobizantes pesquisados e utilizados o ?leo de linha?a foi o pioneiro. Neste trabalho procurou-se avaliar a capacidade de remo??o de HPAs utilizando a vermiculita hidrofobizada com ?leo de linha?a e tamb?m a parafina, para isto fez-se uso do planejamento fatorial completo 24 como ferramenta principal para realiza??o dos experimentos. Avaliou-se tamb?m a granulometria da argila (-20+48 e -48+80 #), o percentual de hidrofobizante aplicado (5 e 10 %) e a salinidade da ?gua produzida sintetizada em laborat?rio (35.000 e 55.000 ppm). A espectroscopia de fluoresc?ncia molecular devido a sua sensibilidade e rapidez foi utilizada para verificar a capacidade de adsor??o da argila, bem como a cromatografia gasosa serviu como t?cnica auxiliar a fim de quantificar e identificar os HPAs presentes em solu??o. A fim de caracterizar a vermiculita fez-se uso da fluoresc?ncia de raios X e difra??o de raios X. O infravermelho e a termogravimetria foram essenciais para constatar a hidrofobiza??o e a quantidade de recobrimento do argilomineral. De acordo com as an?lises de fluoresc?ncia verificou-se que o ensaio 12 obteve o melhor resultado em torno de 98 % de adsor??o dos compostos fluorescentes, contudo a elevada salinidade, a menor granulometria, o maior percentual de hidrofobizante e o uso do ?leo de linha?a apresentaram maior efici?ncia na capacidade de remo??o destes hidrocarbonetos, de acordo com a tend?ncia seguida pela an?lise dos fatores principais do planejamento fatorial. Para verificar a capacidade de adsor??o da argila utilizando um volume fixo de ?gua produzida sint?tica, usou-se como base o ensaio 12, nos seus respectivos n?veis e fatores. Deste modo, observou-se que ap?s a adi??o de aproximadamente 1 ? litro de solu??o de ?gua produzida sint?tica, cerca de 300 vezes o seu volume em massa, a vermiculita foi capaz de adsorver 80 % das esp?cies fluorescentes presentes em solu??o
62

Remo??o, por flota??o, de ?leo em ?guas produzidas na ind?stria de petr?leo: efici?ncia e modelagem do processo

Andrade, Jo?o Marconi de 30 March 2009 (has links)
Made available in DSpace on 2014-12-17T15:42:05Z (GMT). No. of bitstreams: 1 JoaoMApdf.pdf: 2174206 bytes, checksum: a1de24fc592da4515b2bf51d89278503 (MD5) Previous issue date: 2009-03-30 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The separation oil-water by the use of flotation process is characterized by the involvement between the liquid and gas phases. For the comprehension of this process, it s necessary to analyze the physical and chemical properties command float flotation, defining the nature and forces over the particles. The interface chemistry has an important role on the flotation technology once, by dispersion of a gas phase into a liquid mixture the particles desired get stuck into air bubbles, being conduced to a superficial layer where can be physically separated. Through the study of interface interaction involved in the system used for this work, was possible to apply the results in an mathematical model able to determine the probability of flotation using a different view related to petroleum emulsions such as oil-water. The terms of probability of flotation correlate the collision and addition between particles of oil and air bubbles, that as more collisions, better is the probability of flotation. The additional probability was analyzed by the isotherm of absorption from Freundlich, represents itself the add probability between air bubbles and oil particles. The mathematical scheme for float flotation involved the injected air flow, the size of bubbles and quantity for second, the volume of float cell, viscosity of environment and concentration of demulsifier. The results shown that the float agent developed by castor oil, pos pH variation, salt quantity, temperature, concentration and water-oil quantity, presented efficient extraction of oil from water, up to 95%, using concentrations around 11 ppm of demulsifier. The best results were compared to other commercial products, codified by ―W‖ and ―Z‖, being observed an equivalent demulsifier power between Agflot and commercial product ―W‖ and superior to commercial product ―Z‖ / A separa??o ?leo/?gua pelo processo de flota??o ? caracterizada pelo envolvimento entre as fases l?quida e gasosa. Para a compreens?o desse processo, ? necess?rio estudar as propriedades f?sicas e qu?micas que governam a flota??o, estabelecendo a natureza e as for?as entre as part?culas. A qu?mica de interfaces desempenha um papel importante na tecnologia de flota??o, onde, por dispers?o de uma fase gasosa em uma mistura na fase l?quida, as part?culas a serem flotadas prendem-se ?s bolhas de ar e s?o conduzidas at? a camada superficial da solu??o, onde s?o separadas fisicamente. Atrav?s do estudo das intera??es interfaciais envolvidas, foi poss?vel aplicar seus resultados em uma equa??o que determina a probabilidade de flota??o por uma nova ?tica relacionada ?s emuls?es de petr?leo do tipo ?leo/?gua. Os termos da probabilidade de flota??o correlacionam os fen?menos de colis?o e de ades?o entre as part?culas de ?leo e as bolhas de ar. Na probabilidade de colis?o observa-se que quanto maior o n?mero de colis?es maior a probabilidade de flota??o. A probabilidade de ades?o foi analisada atrav?s da isoterma de adsor??o de Freundlich, que representa a probabilidade de ades?o entre as bolhas de ar e as part?culas de ?leo. A modelagem matem?tica para a flota??o envolveu o fluxo de ar injetado, o tamanho das bolhas de ar, a quantidade de bolhas por segundo, o volume da c?lula de flota??o, a viscosidade e a concentra??o do desemulsificante. Os resultados mostraram que o agente de flota??o desenvolvido a partir do ?leo de mamona, ap?s a varia??o do pH, salinidade, temperatura, concentra??o de desemulsificante e teor de ?leo/?gua, apresentou uma efici?ncia de remo??o de ?leo em ?gua acima dos 95%, usando uma concentra??o em torno de 11 ppm de desemulsificante. Os melhores resultados foram comparados com outros produtos comerciais, codificados por ―W‖ e ―Z‖, sendo observado um poder desemulsificante equivalente entre o Agflot e o produto comercial ―W‖ e superior ao produto comercial ‖Z‖
63

Desenvolvimento e teste de um modelo estat?stico de identifica??o das propor??es de ?gua produzida em zonas de produ??o de um campo maduro de petr?leo

Figueredo, Kyt?ria Sabina Lopes de 26 February 2013 (has links)
Made available in DSpace on 2014-12-17T15:42:17Z (GMT). No. of bitstreams: 1 KyteriaSLF_TESE.pdf: 2934284 bytes, checksum: 962e569af56d47cdfb0e3425d7b7a8b9 (MD5) Previous issue date: 2013-02-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This study investigates the chemical species produced water from the reservoir areas of oil production in the field of Monte Alegre (onshore production) with a proposal of developing a model applied to the identification of the water produced in different zones or groups of zones.Starting from the concentrations of anions and c?tions from water produced as input parameters in Linear Discriminate Analysis, it was possible to estimate and compare the model predictions respecting the particularities of their methods in order to ascertain which one would be most appropriate. The methods Resubstitution, Holdout Method and Lachenbruch were used for adjustment and general evaluation of the built models. Of the estimated models for Wells producing water for a single production area, the most suitable method was the "Holdout Method and had a hit rate of 90%. Discriminant functions (CV1, CV2 and CV3) estimated in this model were used to modeling new functions for samples ofartificial mixtures of produced water (producedin our laboratory) and samples of mixtures actualproduced water (water collected inwellsproducingmore thanonezone).The experiment with these mixtures was carried out according to a schedule experimental mixtures simplex type-centroid also was simulated in which the presence of water from steam injectionin these tanks fora part of amostras. Using graphs of two and three dimensions was possible to estimate the proportion of water in the production area / Esse estudo investiga as esp?cies qu?micas presentes na ?gua produzida proveniente das zonas reservat?rio de produ??o de petr?leo no campo de Monte Alegre (produ??o onshore ) com a proposta de desenvolver um modelo aplicado ? identifica??o da ?gua produzida nas diferentes zonas ou grupos de zonas. A partir das concentra??es de ?nions e c?tions da ?gua produzida como par?metros de entrada na An?lise Discriminante Linear, foi poss?velcomparar os modelos de previs?o, respeitando as particularidades dos m?todos aplicados, a fim de indagar qual deles seria o mais adequado. Os m?todos Resubstitui??o, "Holdout Method" e Lachenbruch foram utilizados para ajuste e avalia??o geral dos modelos constru?dos. Dos modelos estimados para po?os produzindo ?gua por uma ?nica zona de produ??o, o m?todo mais adequado foi o "Holdout Method que apresentou taxa de acerto de 90%. As fun??es discriminantes (CV1, CV2 e CV3) estimadas nesse modelo foram utilizadas para modelar novas fun??es para amostras de misturas artificiais de ?gua produzida (produzidas em laborat?rio) e amostras de misturas reais de ?gua produzida (coletadas em po?os produzindo ?gua por mais de uma zona). O experimento com as referidas misturas foi executado de acordo com um planejamento experimental para misturas do tipo simplex-centroid no qual tamb?m, foi simulada a presen?a de ?gua proveniente de inje??o de vapor nestes reservat?rios para uma parte das amostras. Utilizando gr?ficos de duas e tr?s dimens?es foi poss?vel estimar a propor??o de ?gua nas zona de produ??o
64

Polyamide desalination membrane characterization and surface modification to enhance fouling resistance

Van Wagner, Elizabeth Marie 31 January 2011 (has links)
The market for polyamide desalination membranes is expected to continue to grow during the coming decades. Purification of alternative water sources will also be necessary to meet growing water demands. Purification of produced water, a byproduct of oil and gas production, is of interest due to its dual potential to provide water for beneficial use as well as to reduce wastewater disposal costs. However, current polyamide membranes are prone to fouling, which decreases water flux and shortens membrane lifetime. This research explored surface modification using poly(ethylene glycol) diglycidyl ether (PEGDE) to improve the fouling resistance of commercial polyamide membranes. Characterization of commercial polyamide membrane performance was a necessary first step before undertaking surface modification studies. Membrane performance was found to be sensitive to crossflow testing conditions. Concentration polarization and feed pH strongly influenced NaCl rejection, and the use of continuous feed filtration led to higher water flux and lower NaCl rejection than was observed for similar tests performed using unfiltered feed. Two commercial polyamide membranes, including one reverse osmosis and one nanofiltration membrane, were modified by grafting PEGDE to their surfaces. Two different PEG molecular weights (200 and 1000) and treatment concentrations (1% (w/w) and 15% (w/w)) were studied. Water flux decreased and NaCl rejection increased with PEGDE graft density ([microgram]/cm2), although the largest changes were observed for low PEGDE graft densities. Surface properties including hydrophilicity, roughness and charge were minimally affected by surface modification. The fouling resistance of modified and unmodified membranes was compared in crossflow filtration studies using model foulant solutions consisting of either a charged surfactant or an oil in water emulsion containing n-decane and a charged surfactant. Several PEGDE-modified membranes demonstrated improved fouling resistance compared to unmodified membranes of similar initial water flux, possibly due to steric hindrance imparted by the PEG chains. Fouling resistance was higher for membranes modified with higher molecular weight PEG. Fouling was more extensive for feeds containing the cationic surfactant, potentially due to electrostatic attraction with the negatively charged membranes. However, fouling was also observed in the presence of the anionic surfactant, indicating hydrodynamic forces are also responsible for fouling. / text
65

Evaluation of Membrane Treatment Technology to Optimize and Reduce Hypersalinity Content of Produced Brine for Reuse in Unconventional Gas Wells

Eboagwu, Uche 2011 August 1900 (has links)
Over 18 billion barrels of waste fluids are generated annually from oil and gas production in the United States. As a large amount of water is used for oilfield operations, treating and reusing produced water can cut the consumption of fresh water in well sites. This research has helped to develop a membrane process train for a mobile produced water treatment unit for treating oilfield produced brine for reuse. To design the process train, over 30 sets of combination tests at pilot laboratory scale were performed using pretreatment, microfiltration and nanofiltration processes. Membrane performance was selected based on high flux separation efficiency, high tolerance for solids and fluid treatments. Over 95 % solids rejection and greater than 80 % oil removal efficiency were obtained in all these tests. Process train (pre-treatment and membrane) performance was monitored by chemical analysis of permeate and models fitting experimental data for the process. From the results, hydrocarbon rejection was analyzed; total organic carbon rejection was 47.9 %, total carbon content averaged 37.3 % rejection and total inorganic carbon rejection was at 3.66 %. BTEX removal efficiency ranged from 0.98 % to 52.7 % with the progressive pretreatment methods of using cartridge filters. The nanofiltration membrane showed significant reduction in total dissolved solids and in both anionic and cationic species. The process train is seen to follow a sequence of treatment from cartridge and oil removal filter treatment to microfiltration treatment to ultrafiltration, followed by nanofiltration for the purpose of this research. Further research still needs to be done on to determine the kind of analytical test which will give real time feedback on effectiveness of filters. In summary, the process train developed by TAMU-GPRI possesses distinct advantages in treating oilfield produced brine using membrane technology. These advantages include high quality of permeate, reduced sludge and the possibility of total recycle water systems. The small space requirement, moderate capital costs and ease of operation associated with the use of the mobile unit membrane technology also makes it a very competitive alternative to conventional technologies.
66

Desempenho e validação de um sistema com automação para processos de separação água/óleo com membranas cerâmicas. / Performance and validation of a system with automation processes for separating water / oil with ceramic membranes.

BARBOSA, Tellys Lins Almeida. 30 April 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-30T17:51:31Z No. of bitstreams: 1 TELLYS LINS DE ALMEIDA BARBOSA - DISSERTAÇÃO PPGEQ 2014..pdf: 2340446 bytes, checksum: 3a2ea16e16c4359a82b431379410d16c (MD5) / Made available in DSpace on 2018-04-30T17:51:31Z (GMT). No. of bitstreams: 1 TELLYS LINS DE ALMEIDA BARBOSA - DISSERTAÇÃO PPGEQ 2014..pdf: 2340446 bytes, checksum: 3a2ea16e16c4359a82b431379410d16c (MD5) Previous issue date: 2014-09-26 / O presente trabalho visa estudar o desempenho e validação de um sistema com automação para processos de separação de águas oleosas com membranas cerâmicas. O trabalho foi dividido em duas partes: testes em escala de bancada e no sistema com automação. Nos ensaios em escala de bancada foram realizados experimentos de caracterização da membrana cerâmica com água deionizada e com efluente sintético, com intuito de estimar o comportamento das membranas para auxiliar no desenvolvimento do sistema com automação. Para avaliar o desempenho dos sistemas de separação água/óleo com membranas cerâmicas os seguintes parâmetros foram analisados: fluxo do permeado (J, em L/h.m2) e taxa de rejeição de óleo. Nos experimentos no sistema com automação foi avaliado o desempenho no processo de separação água/óleo com membranas cerâmicas, o efluente sintético utilizado obedeceu às mesmas condições do sistema de bancada. Os experimentos com efluente sintético foram simulados com concentração de óleo fixada em 20 mg/L. Observou-se que a redução do fluxo de permeado com o tempo de operação é fortemente dependente da pressão e do teor de óleo emulsionado, podendo ser relacionada aos fenômenos de polarização por concentração, inerentes aos PSM. Contudo, a redução do fluxo no permeado foi atenuada no sistema com automação que possui processos de limpeza backpulse e backwash. Quanto à taxa de rejeição da fase dispersa, para todas as condições analisadas, apresentou-se maior que 97%. A utilização do backwash tendo como agente de limpeza uma solução de hidróxido de sódio não foi eficaz na recuperação do fluxo do permeado, porém o comportamento do processo de limpeza foi extremamente satisfatório o que indica com a mudança do agente de limpeza no processo terá uma melhor recuperação do fluxo do permeado. A partir dos experimentos realizados no sistema com automação os resultados obtidos demostram potencial para separação com membranas cerâmica, para o tratamento de águas oleosas. / This work aims to study the performance and validation of system with automation to oily water separation processes with ceramic membranes. It was divided into two phases: laboratory-scale tests and tests with the system with automation. In the laboratory-scale tests, experiments to characterize the ceramic membrane were carried out with deionized water and synthetic effluent, aiming to estimate the behavior of membranes to assist the developing of the system with automation. To evaluate the performance of the water-oil separation systems with ceramic membranes the following parameters were analyzed: permeate flow (J, L/h.m2) and oil rejection rate. In the experiments with the automatic system the performance was evaluated in oil-water separating process with ceramic membrane, the synthetic effluent used followed the same conditions as the benchtop system. The experiments with synthetic effluent were simulated with oil concentration set at 20 mg/L. It was observed that the reduction of the permeate flux with the operation time is strongly dependent of the pressure and emulsified oil content, may be related to concentration polarization, inherent to membrane separation processes. However, the reduction of permeate flow was attenuated in the system with automation where backpulse and blackwash cleaning processes were used. The dispersed phase rejection rate, for all conditions analyzed, was greater than 97%. The backwash cleaning system having sodium hydroxide as cleaning agent was not effective to increase the permeate flow, but the cleaning agent performance was extremely satisfactory which indicates that the change of the cleaning agent in the process will increase the flow in the permeate stream. From the experiments carried out with the system with automation results demonstrate the potential for separation with ceramic membranes, for oily water treatment.
67

Uso de argilominerais e diatomita como adsorvente de fen?is em ?guas produzidas na ind?stria de petr?leo

Braga, Renata Martins 06 October 2008 (has links)
Made available in DSpace on 2014-12-17T14:08:30Z (GMT). No. of bitstreams: 1 RenataMB.pdf: 1298674 bytes, checksum: 2e9416ef564ec644655637fb323bdd4d (MD5) Previous issue date: 2008-10-06 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The oil production in Brazil has been increasing each year. Consequently, increasing volumes of water produced are generated with large quantities of contaminants, which brings many problems in disposing of these waters. The concern that the concentrations of contaminants in water produced meet existing laws for disposal of effluents, has been extremely important for the development of different techniques for treatment of water produced. The study of clay minerals as adsorbents of organic contaminants has grown considerably so in order to combine the low cost with the efficiency of environmental preservation and health issues. Thus, this study aims to understand the characteristics of vermiculite clay, sodium bentonite, calcium bentonite and diatomite and evaluate their performance as adsorbents for phenol in the water produced. Through adsorption isotherms it was possible to observe the behavior of these adsorptive clay and diatomite for adsorption of phenol, the main phenolic compound found in water produced. Different concentrations of synthetic solutions of phenol were put in touch with these adsorbents under same conditions of agitation and temperature. The adsorbents were composted adsorptive favorable, but the vermiculite and diatomite showed little capacity for absorption, being suggested for absorbs small concentrations of phenol in the balance isothermal / A produ??o de petr?leo no Brasil vem aumentando a cada ano. Em conseq??ncia, volumes crescentes de ?gua de produ??o s?o gerados com grandes quantidades de contaminantes, o que traz v?rios problemas no descarte dessas ?guas. A preocupa??o para que as concentra??es dos contaminantes da ?gua produzida atendam as legisla??es vigentes para descarte de efluentes, tem sido extremamente importante para o desenvolvimento de diferentes t?cnicas de tratamentos da ?gua produzida. O estudo de argilominerais como adsorventes de contaminantes org?nicos tem crescido de forma consider?vel, a fim de se aliar o baixo custo com a efici?ncia da preserva??o ambiental e sa?de publica. Assim, este trabalho tem como objetivo conhecer as caracter?sticas dos argilominerais vermiculita, bentonita s?dica, bentonita c?lcica e da diatomita e avaliar seus desempenhos como adsorventes de fen?is na ?gua produzida. Atrav?s das isotermas de adsor??o p?de-se abservar os comportamentos adsortivos desses argilominerais e da diatomita para adsor??o do fenol, principal composto fen?lico encontrado na ?gua produzida. Diferentes concentra??es de solu??es sint?ticas de fenol foram postas em contato com estes adsorventes sob agita??o e mesmas condi??es de temperatura. Os adsorventes apresentaram comportamento adsortivo favor?vel, por?m a vermiculita e diatomita apresentaram pequena capacidade de adsor??o, sendo sugeridas para adsorver pequenas concentra??es de fenol no equil?brio isot?rmico
68

Estudo de reatores eletroqu?micos para remo??o de Cu2+ , Zn2+, Fenol e BTEX em ?gua produzida

Ramalho, Adriana Margarida Zanbotto 01 August 2008 (has links)
Made available in DSpace on 2014-12-17T14:08:31Z (GMT). No. of bitstreams: 1 AdrianaMZR.pdf: 1640551 bytes, checksum: 6e342552b459e9af8b4b603e028a87b3 (MD5) Previous issue date: 2008-08-01 / The production of water has become one of the most important wastes in the petroleum industry, specifically in the up stream segment. The treatment of this kind of effluents is complex and normally requires high costs. In this context, the electrochemical treatment emerges as an alternative methodology for treating the wastewaters. It employs electrochemical reactions to increase the capability and efficiency of the traditional chemical treatments for associated produced water. The use of electrochemical reactors can be effective with small changes in traditional treatments, generally not representing a significant additional surface area for new equipments (due to the high cost of square meter on offshore platforms) and also it can use almost the same equipments, in continuous or batch flow, without others high costs investments. Electrochemical treatment causes low environmental impact, because the process uses electrons as reagent and generates small amount of wastes. In this work, it was studied two types of electrochemical reactors: eletroflocculation and eletroflotation, with the aim of removing of Cu2+, Zn2+, phenol and BTEX mixture of produced water. In eletroflocculation, an electrical potential was applied to an aqueous solution containing NaCl. For this, it was used iron electrodes, which promote the dissolution of metal ions, generating Fe2+ and gases which, in appropriate pH, promote also clotting-flocculation reactions, removing Cu2+ and Zn2+. In eletroflotation, a carbon steel cathode and a DSA type anode (Ti/TiO2-RuO2-SnO2) were used in a NaCl solution. It was applied an electrical current, producing strong oxidant agents as Cl2 and HOCl, increasing the degradation rate of BTEX and phenol. Under different flow rates, the Zn2+ was removed by electrodeposition or by ZnOH formation, due the increasing of pH during the reaction. To better understand the electrochemical process, a statistical protocol factor (22) with central point was conducted to analyze the sensitivity of operating parameters on removing Zn2+ by eletroflotation, confirming that the current density affected the process negatively and the flow rate positively. For economical viability of these two electrochemical treatments, the energy consumption was calculated, taking in account the kWh given by ANEEL. The treatment cost obtained were quite attractive in comparison with the current treatments used in Rio Grande do Norte state. In addition, it could still be reduced for the case of using other alternative energy source such as solar, wind or gas generated directly from the Petrochemical Plant or offshore platforms / A produ??o de ?gua tem sido a maior corrente de res?duos da ind?stria do petr?leo no segmento de Explora??o e Produ??o E&P. O tratamento deste efluente al?m de ser complexo, requer um alto custo. Neste contexto, surge o tratamento eletroqu?mico como uma metodologia alternativa que empregando rea??es de eletr?lise possibilita aumentar a capacidade e a efici?ncia do tratamento f?sico-qu?mico tradicional da ?gua produzida. A implanta??o de reatores eletroqu?micos pode ser efetivada com pequena modifica??o numa esta??o de tratamento tradicional, sem demandar ?rea significativa (tendo em vista o alto custo do metro quadrado nas plataformas em alto mar), aproveitando os equipamentos existentes, podendo realizar tratamento cont?nuo ou em bateladas, sem a necessidade de investimentos elevados. O tratamento eletrol?tico causa baixo impacto ambiental, pois o processo utiliza el?trons como reagente e gera poucos res?duos. Neste trabalho foram estudados dois tipos de reatores eletroqu?micos: um eletrofloculador e um eletroflotador, tendo como objetivo a remo??o de Cu2+, Zn2+ , fenol e BTEX presentes na ?gua produzida. No eletrofloculador aplicou-se um potencial el?trico a uma solu??o aquosa contendo NaCl, atrav?s de eletrodos de ferro, que promovendo a dissolu??o deste metal com a gera??o de ?ons Fe2+ e gases que em pH apropriado formou rea??es de coagula??o-flocula??o removendo Cu2+ e Zn2+. No eletroflotador utilizou-se c?todo de a?o carbono e ?nodo do tipo DSA de Ti/TiO2-RuO2-SnO2, em solu??o contendo NaCl, que atrav?s de uma corrente el?trica produziu agentes oxidantes fortes como Cl2 e HOCl que ajudaram a degradar o BTEX e fenol em diferentes vaz?es; o Zn2+ foi removido por eletrodeposi??o ou pela forma??o de ZnOH devido ao aumento de pH durante a rea??o. Para compreender o processo eletroqu?mico foi realizado um planejamento fatorial 22 com ponto central para avaliar a sensibilidade dos par?metros operacionais que influenciaram no processo de remo??o de Zn2+ na eletroflota??o, de forma que a densidade de corrente influenciou positivamente e a vaz?o negativamente. Como indicador da viabilidade econ?mica do tratamento eletroqu?mico foram analisados os consumos energ?ticos dos reatores tomando como base o valor kWh cobrado pela ANEEL. Os custos dos tratamentos desta pesquisa foram mais atrativos quando comparados ao utilizado atualmente no Rio Grande do Norte, podendo ser reduzidos caso seja utilizada fontes de energia alternativas, como solar, e?lica ou a g?s gerada no pr?prio P?lo Petroqu?mico ou plataformas
69

Estudo de adsorvente obtido de terras diatom?ceas para remo??o de metais pesados em ?guas produzidas: processamento, caracteriza??o e din?mica em leito fixo

Fontes, Vilsin?ia dos Anjos 02 August 2010 (has links)
Made available in DSpace on 2014-12-17T14:08:40Z (GMT). No. of bitstreams: 1 VilsineiaAF_DISSERT.pdf: 2438653 bytes, checksum: 9241425e98a35008922b9e1dd051a3af (MD5) Previous issue date: 2010-08-02 / The acceleration of industrial growth in recent decades on all continents aroused the interest of the companies to counter the impacts produced on the environment, spurred primarily by major disasters in the petroleum industry. In this context, the water produced is responsible for the largest volume of effluent from the production and extraction of oil and natural gas. This effluent has in its composition some critical components such as inorganic salts, heavy metals (Fe, Cu, Zn, Pb, Cd, ), presence of oil and chemicals added in the various production processes. In response to impact, have been triggered by research alternative adsorbent materials for water treatment and water produced, in order to removing oils and acids and heavy metals. Many surveys of diatomaceous earth (diatomite) in Brazil involve studies on the physico-chemical, mineral deposits, extraction, processing and applications. The official estimated Jazi are around 2.5 million tonnes, the main located in the states of Bahia (44%) and Rio Grande do Norte (37,4%). Moreover, these two states appear as large offshore producers, earning a prominent role in research of adsorbents such as diatomite for treatment of water produced. Its main applications are as an agent of filtration, adsorption of oils and greases, industrial load and thermal insulator. The objective of this work was the processing and characterization of diatomite diatomaceous earth obtained from the municipality of Maca?ba-RN (known locally as tabatinga) as a low cost regenerative adsorbent for removal of heavy metals in the application of water produced treatment. In this work we adopted a methodology for batch processing, practiced by small businesses located in producing regions of Brazil. The characterization was made by X-ray diffraction (XRD), scanning electron microscopy (SEM) and specific surface area (BET). Research conducted showed that the improvement process used was effective for small volume production of diatomite concentrated. The diatomite obtained was treated by calcination at temperature of 900 oC for 2 hours, with and without fluxing Na2CO3 (4%), according to optimal results in the literature. Column adsorption experiments were conducted to percolation of the in nature, calcined and calcined fluxing diatomites. Effluent was used as a saline solution containing ions of Cu, Zn, Na, Ca and Mg simulating the composition of produced waters in the state of Rio Grande do Norte, Brazil. The breakthrough curves for simultaneous removal of copper ions and zinc as a result, 84.3% for calcined diatomite and diatomite with 97.3 % for fluxing. The calcined fluxing diatomite was more efficient permeability through the bed and removal of copper and zinc ions. The fresh diatomite had trouble with the permeability through the bed under the conditions tested, compared with the other obtained diatomite. The results are presented as promising for application in the petroleum industry / A acelera??o do crescimento industrial nas ?ltimas d?cadas despertou em todos os continentes o interesse das empresas em se contrapor aos impactos produzidos sobre o meio ambiente, incentivadas principalmente pelas grandes cat?strofes ocorridas na ind?stria do petr?leo. Nesse contexto, a ?gua produzida ? respons?vel pelo maior volume de efluentes provenientes de processos de produ??o e extra??o de petr?leo e g?s natural. Este efluente tem em sua composi??o alguns componentes cr?ticos como sais inorg?nicos, metais pesados (Fe, Cu, Zn, Pb, Cd,...), presen?a de ?leo e de produtos qu?micos adicionados nos diversos processos de produ??o. Como resposta a estes problemas foram desencadeadas pesquisas com materiais adsorventes alternativos para o tratamento de ?guas produzidas e ?guas residuais, com a finalidade de remo??o de ?leos e graxos e de metais pesados. Muitas pesquisas feitas com terras de diatom?ceas (diatomita) no Brasil envolvem estudos sobre as caracter?sticas f?sico-qu?micas, jazidas, extra??o, beneficiamento e aplica??es. As jaziadas oficiais estimadas s?o da ordem de 2,5 milh?es de toneladas, sendo as principais localizadas nos estados da Bahia (44%) e Rio Grande do Norte (37,4%). Por outro lado, esses dois estados apresentam-se como grandes produtores de petr?leo em terra, merecendo um destaque importante nas pesquisas de adsorventes como a diatomita para tratamento de ?gua produzida. Suas principais aplica??es s?o como agente de filtra??o, adsor??o de ?leos e graxas, carga industrial e isolante t?rmico. Esse trabalho tem como objetivo o beneficiamento e a caracteriza??o da diatomita do munic?pio de Maca?ba-RN (conhecida na regi?o como tabatinga) como um adsorvente regenerativo de baixo custo para fins de remo??o de metais pesados na aplica??o do tratamento de ?guas produzidas. No presente trabalho adotou-se uma metodologia de beneficiamento por batelada, praticada por pequenas empresas estabelecidas nas regi?es produtoras do Brasil. A caracteriza??o foi feita por difra??o de raios-X (DRX), microscopia eletr?nica de varredura (MEV) e ?rea superficial espec?fica (BET). A investiga??o conduzida mostrou que o processo de beneficiamento utilizado foi eficaz para produ??o em pequena escala de diatomita concentrada. A diatomita obtida foi tratada por calcina??o na temperatura de 900 oC por 2 horas, sem e com fluxante carbonato de s?dio (Na2CO3, 4 %), de acordo com resultados otimizados na literatura. Ensaios de adsor??o em coluna de percola??o foram realizados para as diatomitas in natura, calcinada, e calcinada com fluxante. Como efluente foi utilizado uma solu??o sint?tica contendo ?ons de Cu, Zn, Na, Ca e Mg, simulando a composi??o de ?guas produzidas no estado do Rio Grande do Norte-Brasil. As curvas de ruptura para remo??o simult?nea dos ?ons de cobre e zinco apresentaram como resultados, 84,3 % para diatomita calcinada e 97,3 % para diatomita com fluxante. A diatomita calcinada com fluxante apresentou maior efici?ncia na permeabilidade atrav?s do leito e na remo??o dos ions de cobre e zinco. A diatomita in natura teve dificuldade com a permeabilidade atrav?s do leito nas condi??es testadas, comparada com as outras diatomitas. Os resultados obtidos apresentam-se como promissores para aplica??o na ind?stria do petr?leo
70

Extra??o de metais (K, Mg, Ba, Ca, Cr, Mn, Li, Fe) de ?gua produzida utilizando sistema microemulsionado

Nascimento, Yasmine ?sis Fernandes do 07 January 2014 (has links)
Made available in DSpace on 2014-12-17T14:08:54Z (GMT). No. of bitstreams: 1 YasmineIFN_DISSERT.pdf: 3060416 bytes, checksum: 9c16a86ed5e6a8b081b1d3520826bad4 (MD5) Previous issue date: 2014-01-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The produced water is a byproduct formed due to production of petroleum and carries with it a high amount of contaminants such as oil particles in suspension, organic compounds and metals. Thus, these latter pollutants are very difficult to treat because of its high solubility in water. The objective of this work is to use and evaluate a microemulsioned system to remove metals ( K , Mg , Ba , Ca , Cr , Mn , Li , Fe ) of synthetic produced water. For the extraction of metals, it was used a pseudoternary diagram containing the following phases: synthetic produced water as the aqueous phase (AP), hexane as organic phase (OP), and a cosurfactant/surfactant ratio equal to four (C/S = 4) as the third phase, where the OCS (saponified coconut oil) was used as surfactant and n-butanol as cosurfactant. The synthetic produced water was prepared in a bench scale and the region of interest in the diagram for the removal of metals was determined by experimental design called. Ten points located in the phase Winsor II were selected in an area with a large amount of water and small amounts of reagents. The samples were analyzed in atomic absorption spectrometer, and the results were evaluated through a statistical assesment, allowing the efficiency analysis of the effects and their interactions. The results showed percentages of extraction above 90% for the metals manganese, iron, chromium, calcium, barium and magnesium, and around 45% for metals lithium and potassium. The optimal point for the simultaneous removal of metals was calculated using statistical artifact multiple response function (MR). This calculation showed that the point of greatest extraction of metals occurs was the J point, with the composition [72% AP, 9% OP, 19% C/S], obtaining a global extraction percentage about 80%. Considering the aspects analyzed, the microemulsioned system has shown itself to be an effective alternative in the extraction of metals on synthetic produced water remediation / A ?gua produzida ? um subproduto gerado na produ??o do petr?leo e possui uma grande quantidade de contaminantes, tais como part?culas de ?leo em suspens?o, compostos org?nicos e metais, sendo estes ?ltimos poluentes de dif?cil tratamento devido a sua alta solubilidade em ?gua. O objetivo deste trabalho ? utilizar e avaliar um sistema microemulsionado na extra??o de metais (K, Mg, Ba, Ca, Cr, Mn, Li, Fe) contidos na ?gua produzida. Utilizou-se um diagrama pseudotern?rio de um sistema contendo em sua composi??o: ?gua produzida sint?tica como fase aquosa (FA), hexano como fase org?nica (FO), e uma raz?o cotensoativo/tensoativo igual a quatro (C/T=4), sendo utilizado o OCS (?leo de coco saponificado) como tensoativo e n-butanol como cotensoativo. A ?gua produzida sint?tica foi preparada em escala de bancada e a regi?o de interesse para a remo??o dos metais foi determinada atrav?s do planejamento experimental de mistura, sendo escolhidos dez pontos localizados na fase de Winsor II, em uma ?rea com uma grande quantidade de ?gua e pouca quantidade de mat?ria ativa ou solvente. As amostras foram analisadas no espectr?metro de absor??o at?mica, e os resultados obtidos foram avaliados atrav?s de um tratamento estat?stico permitindo a an?lise da efici?ncia dos efeitos das vari?veis estudadas e suas intera??es. Os resultados apresentaram percentuais de extra??o acima de 90% para os metais mangan?s, ferro, cromo, c?lcio, b?rio e magn?sio, e em torno de 45% para o l?tio e o pot?ssio. O ponto ?timo para a remo??o simult?nea dos metais foi calculado atrav?s do recurso estat?stico de m?ltipla fun??o de resposta (MR). O c?lculo permitiu observar que o ponto onde ocorre o maior percentual de extra??o dos metais foi o ponto J com a composi??o [72% FA, 9% FO, 19% C/T], obtendo percentual de extra??o global em torno de 80% de todos os metais. Tendo em vista os aspectos analisados, o sistema microemulsionado estudado mostrou-se como uma eficiente alternativa na extra??o de metais de ?gua produzida sint?tica

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