Made available in DSpace on 2017-07-20T13:42:00Z (GMT). No. of bitstreams: 1 Juliano Almeida.pdf: 2689795 bytes, checksum: e2c63ba0cfcdfb76d39a3d5e44e5dcf9 (MD5) Previous issue date: 2017-04-20 / Considering the shortage of fresh water availability and an increased demand for water in the world, including Brazil, one of the alternatives for water supply are the water desalination system, which remove salts from brackish or seawater. The objective of this study was to evaluate the efficiency of treated water desalination system with production capacity of 1.0 m3 h-1 of treated water, installed in a water treatment plant of Sanepar (Water and Sanitation Company of the State of Parana), in Praia de Leste located in the coast of the state of Paraná, Brazil. In this study, the seawater was diluted with fresh water to make brackish water. The brackish water was prepared from the water mixture of the Pombas River, source of fresh water supply to the region, and sea water. The mixtures were performed to obtain concentrations of 1000 and 1500 mg L-1 of total dissolved solids (TDS). The system was composed of ultrafiltration (UF) as a pre-treatment to reverse osmosis (RO). Experiments were performed during 15 days for each TDS concentration of brackish water and TDS removal efficiencies were 99.0 and 99.1%, respectively. Besides TDS, other water quality parameters such as: electrical conductivity, turbidity, apparent colour, alkalinity, total hardness, calcium, magnesium, chlorides, sulphates and pH were monitored. Oxidation-reduction potential (ORP) and osmotic pressure, filtration rate and membrane recovery rate were also measured for the RO. The pilot plant system could remove all water quality parameters studied. / Com a escassez da disponibilidade de água doce e o aumento da demanda de água no mundo e também no Brasil, uma das alternativas para o suprimento de água são os sistemas de dessalinização de água, que removem os sais da água salobra ou salgada. Este trabalho teve como objetivo avaliar a eficiência de um sistema piloto de dessalinização de água salobra com capacidade de produção de 1,0 m3 h-1 de água tratada, instalado na estação de tratamento de água (ETA) da Sanepar, no balneário de Praia de Leste, no litoral do estado do Paraná. A água salobra foi preparada a partir da mistura da água bruta do Rio das Pombas, manancial que abastece o balneário, e água do mar. As misturas foram realizadas até obter concentrações de 1000 e 1500 ± 100 mg L-1 de sólidos dissolvidos totais (SDT). O sistema foi composto de ultrafiltração como pré-tratamento à osmose reversa. Os experimentos foram realizados durante o período de 15 dias para cada concentração de SDT da água salobra obtendo-se remoções de 99,0 e 99,1%, para 1500 ± 100 mg L-1 e 1000 ± 100 mg L-1, respectivamente. Além dos SDT, foram avaliados outros parâmetros de qualidade da água como: condutividade elétrica, turbidez, cor aparente, alcalinidade, dureza total, cálcio, magnésio, cloretos, sulfatos, pH e temperatura. Durante os experimentos foram avaliados potencial de oxirredução (ORP) e a pressão osmótica, a taxa de filtração e a taxa de recuperação na membrana de osmose reversa. O sistema de ultrafiltração foi mais eficiente na remoção de turbidez e cor aparente, sendo que o sistema de osmose reversa apresentou melhor eficiência na remoção de sólidos dissolvidos totais.

O objetivo deste estudo foi analisar o desempenho de um sistema de captação e tratamento de água do rio Sarapuí, por meio de uma estação de tratamento composta por um sistema de pré-tratamento convencional, ligado a um sistema de separação por membranas de osmose inversa, no Município de Belford Roxo RJ, instalado para fornecer água de processo a instalações industriais. Foi verificado que a água captada encontra-se em condição bastante degradada e que a unidade de tratamento removeu, em média, 97% do teor dos poluentes presentes na água, enquadrando-a nos parâmetros requeridos pelo processo industrial. Foi possível comprovar que o processo de separação por osmose inversa pode ser utilizado em escala industrial, proporcionando ganhos econômicos consideráveis, além de evitar o consumo de água potável para fins de processos industriais e, ainda, contribuir para a retirada de carga orgânica de uma fonte degradada / The objective of this study was to analyze the performance of a system to capture and treat water from Sarapuí river through a treatment system consisting of a conventional pré-treatment stage, linked to a reverse osmosis separation system membranes, in the city of Belford Roxo - RJ, installed to provide process water for industrial plants. It was found that the water is captured in highly degraded condition and the treatment plant removed an average of 97% of the pollutants in the water, fitting the parameters required by the industrial process. It could be demonstrated that the separation process by reverse osmosis can be used on an industrial scale, providing significant economic gains, and avoid the consumption of potable water for industrial processes and also contribute to the removal of organic pollutants from a degraded source

<p>Deponijski gas koji nastaje kao rezultat anaerobnih procesa unutar<br />otpada na deponiji može da se iskoristi kao obnovljivi izvor<br />energije, smanjujući ujedno i zagađenje vazduha. Tretman procedne vode<br />u savremenim postrojenjima za prečišćavanje reverznom osmozom daje<br />neželjeni ostatak &ndash; koncentrat, koji se uobičajeno recirkuliše na<br />deponiju kao vid tretmana. Ova disertacija se bavi uticajem<br />recirkulacije na produkciju deponijskog gasa, kako bi se omogućila<br />bolja upravljivost i predikcija čitavog procesa upravljanja otpadom<br />sa ciljem održanja stabilne proizvodnje deponijskog gasa i povećanja<br />mogućnosti njegovog iskorišćenja u termo-energetskim postrojenjima.</p> / <p>Landfill gas resulting from the anaerobic processes in the waste at the landfill<br />can be used as a renewable energy source, reducing both air<br />pollution. Treatment of leachate in modern plants for the purification using<br />reverse osmosis gives unwanted residue - concentrate, which is typically<br />recirculated back to the landfill as a form of its treatment. This thesis deals<br />with the influence of recirculation in the production of landfill gas, to allow for<br />better handling and prediction of entire process of waste management in<br />order to maintain stable production of landfill gas and increasing<br />opportunities for its utilization in thermal and power plants.</p>

No / The water permeability constant, (K-w), is one of the many important parameters that affect optimal design and operation of RO processes. In model based studies, e.g. within the RO process model, estimation of W-w is therefore important There are only two available literature correlations for calculating the dynamic K-w values. However, each of them is only applicable for a given membrane type, given feed salinity over a certain operating pressure range. In this work, we develop a time dependent neural network (NN) based correlation to predict K-w in RO desalination processes under fouling conditions. It is found that the NN based correlation can predict the K-w values very closely to those obtained by the existing correlations for the same membrane type, operating pressure range and feed salinity. However, the novel feature of this correlation is that it is able to predict K-w values for any of the two membrane types and for any operating pressure and any feed salinity within a wide range. In addition, for the first time the effect of feed salinity on Kw values at low pressure operation is reported. Whilst developing the correlation, the effect of numbers of hidden layers and neurons in each layer and the transfer functions is also investigated. (C) 2014 Elsevier B.V. All rights reserved.

The ability to produce potable water economically is the primary focus of seawater desalination research. There are numerous methods to desalinate water, including reverse osmosis, multi-stage flash distillation, and multi-effect evaporation. These methods cost more than potable water produced from natural resources; hence an attempt is made in this research project to produce potable water using a modified high-efficiency jet ejector in vapor-compression distillation. The greater efficiency of the jet ejector is achieved by properly mixing propelled and motive streams. From experiments conducted using air, the pressure rise across the jet ejector is better in case of one or two mixing vanes and the highest back pressure (pinch valve closed 83.33%). At other pinch valve closings, the air velocity through the jet ejector was high, so the extra surface area from the mixing vanes caused excessive friction and lowered the efficiency.

Fresh water resources in many of the world's oil producing regions, such as western Texas, are scarce, while produced water from oil wells is plentiful, though unfit for most applications due to high salinity and other contamination. Disposing of this water is a great expense to oil producers. This research seeks to advance a technology developed to treat produced water by reverse osmosis and other means to render it suitable for agricultural or industrial use, while simultaneously reducing disposal costs. Pilot testing of the process thus far has demonstrated the technology's capability to produce good-quality water, but process optimization and control were yet to be fully addressed and are focuses of this work. Also, the use of renewable resources (wind and solar) are analyzed as potential power sources for the process, and an overview of reverse osmosis membrane fouling is presented. A computer model of the process was created using a dynamic simulator, Aspen Dynamics, to determine energy consumption of various process design alternatives, and to test control strategies. By preserving the mechanical energy of the concentrate stream of the reverse osmosis membrane, process energy requirements can be reduced several fold from that of the current configuration. Process control schemes utilizing basic feedback control methods with proportional-integral (PI) controllers are proposed, with the feasibility of the strategy for the most complex process design verified by successful dynamic simulation. A macro-driven spreadsheet was created to allow for quick and easy cost comparisons of renewable energy sources in a variety of locations. Using this tool, wind and solar costs were compared for cities in regions throughout Texas. The renewable energy resource showing the greatest potential was wind power, with the analysis showing that in windy regions such as the Texas Panhandle, wind-generated power costs are approximately equal to those generated with diesel fuel.

The ability to produce potable water economically is the primary focus of seawater desalination research. There are numerous methods to desalinate water, including reverse osmosis, multi-stage flash distillation, and multi-effect evaporation. These methods cost more than potable water produced from natural resources; hence an attempt is made in this research project to produce potable water using a modified high-efficiency jet ejector in vapor-compression distillation. The greater efficiency of the jet ejector is achieved by properly mixing propelled and motive streams. From experiments conducted using air, the pressure rise across the jet ejector is better in case of one or two mixing vanes and the highest back pressure (pinch valve closed 83.33%). At other pinch valve closings, the air velocity through the jet ejector was high, so the extra surface area from the mixing vanes caused excessive friction and lowered the efficiency.

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

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.

This study was to investigate theory and application of Osmotic Distillation (OD). OD is a new novel membrane separation process used for the concentration of aqueous solutions such as fruit juices without the application of heat. The present work was undertaken to investigate flux limitations focusing on feedside, membrane and stripper side characteristics of OD. Once the limiting areas were identified, further studies were undertaken to determine methods of minimizing those limitations without losing the quality and integrity of the liquid feed. A laboratory scale OD system was used to simulate the industrial process which takes place during the production of grape juice concentrate for the fruit juice industry. Results of a UF pretreatment study showed that the use of UF membranes with pore diameters of 0.1 fÝm or less as a pretreatment for the subsequent OD of grape juice resulted in significant increases in OD flux over that observed for juice not subjected to UF. The study of the physical properties of the feed played an important role in the explanation of the OD process. The increase in OD flux was attributed to a reduction in juice viscosity as the result of the removal of protein and other high molecular weight components. Apart from an increase in OD flux, UF pretreatment of the grape juice proved to be beneficial in other areas of the OD process. HPLC measurements showed that the normal concentration of fermentable sugars in standard 68 oBrix concentrate can be achieved at a lower Brix value in feed subjected to UF pretreatment, further reducing the need to handle highly viscous feeds. UF pretreatment also resulted in an increase in juice surface tension consequently reducing the tendency for membrane wet-out to occur. The study of the deoxygenation of the feed solution shows that the removal of dissolved gases by the pre boiling method and the perstraction with chemical reaction (PCR) method both had a positive affect on OD flux. Pre boiling the brine resulted in an indirect reduction in dissolved oxygen in the feed. Pre boiling both the feed and brine, further increased the flux. Throughout the PCR study, it was evident that stripper side mass transfer of O2 was not limited by flowrate but was limited by higher stripper concentration. However, the latter had an insignificant effect when the sulfite-oxygen reaction was catalysed. The use of a catalyst and increase in temperature gave a significant improvement in overall mass transfer coefficient. Ten types of hydrophobic microporous membranes were tested for their influence on OD flux. While the pore diameter is a considerable factor in mass transport of gases through the membrane, it was also noted that the type of membrane material used had an affect on the overall mass transfer. All top three performing membranes had pore diameters of 0.2 x 10-6 m and were made from polytetrafluoroethylene (PTFE). The choice of brine to use as the stripper was based on criteria that were confirmed by the brine studies performed here. The best performing stripper solutions demonstrating the greatest improvement in OD flux over the most commonly used brines, NaCl, CaCl2 and CH3COOK were aqueous solutions of potassium salts of phosphoric acid, pyrophosphoric acid and blends thereof. These salts agreed with all the required characteristics of a suitable brine, demonstrating high solubility rates, supporting the ability to lower water vapour pressure. The study of the corrosion effects of brine salts confirmed the phosphate salts are superior demonstrating some of the lowest corrosion rates and highest pH.