Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2013-04-23T12:03:04Z No. of bitstreams: 1 Joilma Menezes.pdf: 1646474 bytes, checksum: 55d6d57db450f3ab1ef86b3ac1a50087 (MD5) / Made available in DSpace on 2013-04-23T12:03:04Z (GMT). No. of bitstreams: 1 Joilma Menezes.pdf: 1646474 bytes, checksum: 55d6d57db450f3ab1ef86b3ac1a50087 (MD5) Previous issue date: 2009 / Para tornar potáveis águas salobras ou salinas, é necessário fazer a dessalinização, processo que normalmente exige alto investimento e recursos tecnológicos complexos para a produção em larga escala. Neste caso, o preço da água para o consumidor final torna-se muito mais elevado, devido à menor oferta e gastos envolvidos. O objetivo geral desse trabalho foi desenvolver um dispositivo caseiro para dessalinização de pequenas quantidades de água para o uso em dessedentação humana para aplicação em regiões com água de salinidade inadequada para beber, utilizando material biológico, como sementes de espécies de plantas do Semi-Árido baiano ou com possível cultivo naquela região. A metodologia empregada no trabalho foi baseada na medida da salinidade da água antes e após o contato com o material biológico. Dez tipos diferentes de sementes foram estudados: Amendoa (Terminalia Catappa L.), Umbu (Spondndias Tuberosa Cheg. Cam.), Moringa (Moringa Oleifera Lam), Mulungu (Erythrina verna Vell), Umburana (Erythrina verna Vell), Bucha Vegetal (Luffa Cylindrica), Algaroba (Prosopis juliflora), Abobora (Cucúrbita Pepo L., ), Girassol (Helianthus Annus), e Mesocarpo e Endocarpo do Coco (Cocos Nucifera) e para os experimentos utilizou-se água de salinidade 0,7o/oo (baixa salobridade de ocorrência freqüentemente no semi-árido baiano). Após o contato da água salobra com o material biológico determinava-se a concentração de sódio remanescente na água, representando o NaCl, não sorvido pelo material biológico, principal sal responsável pela salinidade da água. Para análise de sódio foi usado a técnica analítica da fotometria de chama (Micronal, Mod. B462). Na escolha final do sorvente a ser usado no dispositivo caseiro foi considerado prioritário, além da maior capacidade de sorção de sais, menor teor de sal intrínseco e abundância na região semi-árida e/ou com possibilidade de adaptação para cultivo naquela região. A semente de umbu (Spondndias Tuberosa Cheg. Cam.) apresentou maior capacidade de sorção de sais da água salobra, principalmente quando seca a 250º C, por 1 hora. Dessa forma desenvolveu-se um dispositivo caseiro para dessalinização de água, em pequenas quantidades, suficientes para o uso familiar em dessedentação humana, a partir desta semente tratada segundo indicação neste trabalho, podendo transformar água de baixa salobridade, mas imprópria para beber (> 0,5 a 1,5 o/oo) em água doce e baixar a alta dureza de águas a níveis de aceitação para consumo humano. O estudo da adsorção dos sais em umbu realizado para explicar o processo de dessalinização da água salobra usando-se material produzido por secagem e moagem da semente do umbu, atendeu ao modelo de Langmuir e permitiu estimar a capacidade máxima de adsorção de sódio pelo umbu a 30, 40 e 50°C em: 52,6, 165 e 250 mg g-1 respectivamente. Desta forma, 1 L de água salobra de salinidade entre 0,6 e como aquelas do Semi Árido baiano testadas, pode ter seu teor de sal removido com apenas 1g daquelas sementes tratadas segundo indicação neste trabalho e aquecendo a água a 50°C. / Salvador

Eastern Europe comprises a significant part of the native ranges for indigenous crayfish species (ICS) belonging to the genus Astacus. This region has been largely overlooked by astacologists and considered relatively immune to the impacts of non-indigenous crayfish species (NICS). The recent discovery of two marbled crayfish Procambarus fallax f. virginalis populations in Ukraine has changed this view. The potential increased propagule pressure (mainly due to pet trade), has raised concerns of NICS which may negatively impair the ecosystems of Azov, Black and Caspian Seas and their tributaries inhabited by ICS. In this study, we provide the first insight into salinity tolerance of marbled crayfish. We performed a 155-day experiment using 5 different salinities (6, 9, 12, 15, and 18 ppt) and a freshwater control. Evaluation of survival, growth and reproduction suggests that marbled crayfish have a lower salinity tolerance than other crayfish species, which may limit their invasive potential in brackish environments. However, its ability to survive for more than 90 days at 18 ppt opens up the possibility of gradual dispersion and adaptation to brackish conditions. Our study highlights the need for further studies elucidating the potential for marbled crayfish to negatively impair these ecosystems.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-03-09T20:44:52Z No. of bitstreams: 1 FRANCISCO RUBENS MACEDO DE QUEIROZ - TESE PPGEQ 2017..pdf: 6491313 bytes, checksum: 6c4f94936ecedff528d64322072a5f31 (MD5) / Made available in DSpace on 2018-03-09T20:44:52Z (GMT). No. of bitstreams: 1 FRANCISCO RUBENS MACEDO DE QUEIROZ - TESE PPGEQ 2017..pdf: 6491313 bytes, checksum: 6c4f94936ecedff528d64322072a5f31 (MD5) Previous issue date: 2016-12-09 / Capes / Um dos grandes desafios da atualidade vem sendo a conservação e manutenção dos corpos de águas do mundo, devido as suas contaminações em função das atividades humana. A diversidade das substâncias toxicas de diferentes naturezas são veiculadas como fontes de doenças de alto risco para todos os seres e vegetações do planeta. Um dos pontos preliminares é o acesso ao saneamento básico que a maioria das cidades brasileiras não possuem e que carreiam seus resíduos para mananciais superficiais e subterrâneas, deixando-os com altos índices de bactérias, inclusive com o aumento da concentração de nitrato nas águas subterrâneas. O presente trabalho visa estudar o desempenho de dois sistemas de membranas para reduzir a concentração de nitrato presente em águas de poços doces e salobros, contendo índices de nitrato acima dos padrões de potabilidade da legislação brasileira. Os desempenhos dos sistemas de membranas de microfiltração/nanofiltração e ultrafiltração/osmose inversa, foram estudados em função de seus limites de pressões de operações para diferentes níveis de concentrações de nitrato presentes nos meios aquosos. Os níveis das pressões de operações para todas as águas estudadas foram obtidos com auxílio de um simulador de processos de membranas (Reverse Osmose System Analysis), o qual contribui para realizar o planejamento experimental em função das pressões de operações versus concentrações nitrato. A primeira fase do trabalho os dois sistemas operaram com uma solução de nitrato na faixa de 0,67 mg.L-1 ≤ [N-N03-] ≤ 23,3 mg.L-1 visando explorar os níveis das taxas rejeição do nitrato em função de suas pressões de operações. Os desempenhos dos dois sistemas de membranas foram estudados com água doce de poço contaminada com nitrato, água de abastecimento da rede do LABDES e água de poço salobra, ambas com adição de 20,8 mg.L-1 de nitrato. Os resultados das taxas de rejeição de nitrato para os dois sistemas foram comparados em função do tipo de água de alimentação e seus níveis de concentrações de nitrato. Observou-se que o sistema de membranas de ultrafiltração/osmose inversa apresentou uma remoção de nitrato superior para todos os casos estudados, quando comparados com os obtidos pelo sistema de microfiltração/nanofiltração. Comparando os resultados para uma pressão de operação comum para os dois sistemas de membranas estudados de 3,2 bar o sistema de membrana de microfiltração/nanofiltração conseguiu uma taxa de remoção de 54,50% e o sistema de ultrafiltração/osmose inversa foi de 86,10% para uma concentração de 20,8 mg.L-1 de nitrato na água doce de poço. Observou-se que uma redução de nitrato e dos sólidos totais dissolvidos em águas doces para os padrões de potabilidade foram significativas para o sistema de ultrafiltração/osmose inversa do que a do sistema de microfiltração/nanofiltração, em função da pressão de operação. Com auxilio do MINITAB Versão 17.0 os modelos foram validados a partir das curvas dos dados experimentais para os dois sistemas de membranas estudados. / One of the great challenges of the present time has been the conservation and maintenance of the bodies of water of the world, due to its contaminations due to human activities. The diversity of toxic substances of different natures are conveyed as sources of high risk diseases for all beings and vegetations of the planet. One of the preliminary points is access to basic sanitation that most Brazilian cities do not have and that carry their waste to surface and underground springs, leaving them with high rates of bacteria, including with increasing nitrate concentration in groundwater. The present work aims to study the performance of two membrane systems to reduce the concentration of nitrate present in waters of sweet and brackish wells, containing nitrate indices above the potability standards of Brazilian legislation. The performances of the microfiltration/nanofiltration and ultrafiltration/reverse osmosis membranes systems were studied as a function of their operating pressure limits for different levels of nitrate concentrations present in the aqueous media. The operating pressure levels for all studied waters were obtained using a Reverse Osmose System Analysis, which contributes to perform the experimental planning as a function of the operating pressures versus nitrate concentrations. In the first phase of the work the two systems operated with a nitrate solution in the range of 0,67 mg.L-1 ≤ [N-N03-] ≤ 23,3 mg.L-1 to explore the levels of nitrate rejection rates as a function of their pressures Operations. The performances of the two membrane systems were studied with fresh water from well contaminated with nitrate, LABDES network water supply and brackish water, both with addition of 20,8 mg.L-1 of nitrate. The results of the nitrate rejection rates for the two systems were compared according to the type of feed water and their levels of nitrate concentrations. It was observed that the ultrafiltration / reverse osmosis membrane system showed superior nitrate removal for all the studied cases when compared to those obtained by the microfiltration / nanofiltration system. Comparing the results to a common operating pressure for the two 3,2 bar membrane systems studied, the microfiltration/nanofiltration membrane system achieved a removal rate of 54,50% and the ultrafiltration/reverse osmosis system was 86,10% for a concentration of 20,8 mg.L-1 nitrate in freshwater well. It was observed that a reduction of nitrate and total solids dissolved in fresh water to the potability standards were significant for the ultrafiltration / reverse osmosis system than that of the microfiltration/nanofiltration system as a function of the operating pressure. With the help of MINITAB Version 17.0 the models were validated from the curves of the experimental data for the two systems of membranes studied.

Fresh water in Kuwait is produced by non- conventional methods. About 95% of this water comes from desalinated seawater using multi-stage flash distillation technique and the remainder comes from underground brackish water. The blended water containes organic, inorganic and trace metal impurities within the recommended international standard limits. The purpose of this work is to identify the source of selected trace metals present in the drinking water in Kuwait. Chromium, copper, iron, lead, manganese, nickel, vanadium and zinc have been analysed using atomic absorption spectroscopy (AAS) and inductively coupled plasma mass spectroscopy (ICPMS). Efforts were made to improve the preconcentration of the selected metals and their separation from the high concentration of salts in seawater which affect the accuracy and cause major interference in the analysis. Solid-liquid extraction (chelex-100 resin) and liquid-liquid extraction (methyl iso-butyl ketone and freon) with and without back-extraction into nitric acid were investigated. Liquid-liquid extraction without back-extraction proved to give optimum recovery of the selected metals. Results confirmed that both AAS and ICP-MS are suitable for the analysis of trace metals in Kuwait's waters. Although AAS technique proved to be more accurate in analysing the selected metals than ICP-MS, the latter was adopted since its accuracy is acceptable (1.1-4.4%) and it is easier and faster than the former technique. The study revealed that the source of copper, iron, nickel and zinc is the construction materials of the distillation plants, while the source of lead and vanadium is the brackish water. Manganese and chromium concentrations are very low in all sources. No direct relationship between the metal concentration in the seawater and the distillate could be deduced.

Water scarcity for agriculture is one of the most important challenges to improve food security worldwide. In this thesis we study the potential to develop a low-cost controller for a small scale brackish desalination plant that consists of proven water treatment technologies, reverse osmosis, cation exchange, and nanofiltration to treat groundwater into two final products: drinking water and irrigation water. The plant is powered by a combination of wind and solar power systems. The low-cost controller uses Arduino Mega, and Arduino DUE, which consist of ATmega2560 and Atmel SAM3X8E ARM Cortex-M3 CPU microcontrollers. These are widely used systems characterized for good performance and low cost. However, Arduino also requires drivers and interfaces to allow the control and monitoring of sensors and actuators. The thesis explains the process, as well as the hardware and software implemented.

The drinking water plant in this case study is a combined groundwater and reverse osmosisplant in the Stockholm archipelago. The reverse osmosis purification step was added to theplant in 1995. This technique is relatively new in Sweden and there are possibilities for it tobecome a good complement to conventional drinking water treatment. The plant has used thistechnique for over 10 years with good results. It is therefore of great interest to evaluate anddocument it for the possibility to implement this technique in areas not connected toconventional drinking water production.Reverse osmosis separates the incoming water to a clean permeate and concentrate ofremoved particles, larger molecules and ions. This technique has a high purification degree. Itcan remove dissolved particles and microorganisms without disinfection. However, it isrelatively expensive due to a high electricity consumption compared to conventional drinkingwater treatment. The high electricity consumption in this kind of system depends on aphenomenon called membrane fouling caused by the constituents in the raw water, graduallybecoming enriched on the membrane surface.The aim of this thesis was to evaluate and document a drinking water plant in the Stockholmarchipelago from a social, economical, technical and environmental perspective. A socialsurvey in the form of a questionnaire was conducted to reveal opinions about the water qualityprovided by the plant. The economical evaluation was done to estimate the cost of drinkingwater production and find the water cost in Kr/m3. The technical part involved documentationof the plant layout and evaluation of its performance. To assess the performance historicalchemical and microbial analyses were evaluated. A mass balance was attempted to drawconclusions for the overall system. The environmental part of the plant assessment, includedan estimate of the electricity and chemicals use in the plant.The results revealed that from an overall perspective the water quality from the plant issatisfactory with some concerns about metal taste and turbidity that sometimes occur. Thepotential presence of dangerous algal toxins in the water was also a concern. The totalproduction cost in Kr/m3 is higher than expected and higher than sales price. In technicalterms, the plant has functioned well. However, there is a need to monitor more parameters inthe plant including; more flow parameters, concentrations of added chemicals and more waterquality parameters. Electricity consumption has been higher than expected. Control(throttling) valves in the brine reject are relatively large energy consumers and arecommendation is to investigate potential savings by changing them for pressure exchangevalves. / www.ima.kth.se

Global growing demand for agricultural production has put increased pressure on freshwater resources in various global locations. Many areas have saline groundwater resources which have not been utilized for agriculture due to the economics associated with water pumping and desalination. Limited availability to electricity and high operational costs of diesel generators are major obstacles to utilization of these resources. Reduced costs associated with large-scale renewable energy have renewed interest in understanding the potential impacts of developing distributed photovoltaic (PV) powered water pumping and desalination systems for agriculture. In order to determine the economic feasibility of solar-powered water pumping and desalination for agriculture, an engineering system model that performs hourly simulations of direct-coupled PV pumping and desalination systems by integrating environmental resource data and industrial component performance data was developed. Optimization algorithms were created to identify the best membrane type, control method and reverse osmosis system configuration for a given set of locational parameters. Economic analysis shows that PV-powered systems are more economical than diesel-powered systems for water pumping, with water desalination costs for PV- and diesel-powered systems being comparable. Grid-powered systems are able to pump and desalinate water for a lower cost than PV or diesel for all cases evaluated. A sensitivity analysis is performed to generalize results for different input parameters and illustrate the impact of input variables on water unit costs. Several case studies in the Jordan Valley were evaluated to illustrate the economic viability of solar-based systems with simulation results including a direct comparison to diesel- and grid-connected alternatives. Results indicate that under fair environmental conditions and irrigating greenhouse vegetables, the PV-, diesel-, and grid-powered systems produce favorable internal rates of return of 40%, 84%, and 248%, respectively. Under poor environmental conditions and less profitable crops the PV-, diesel-, and grid-powered systems all result in negative internal rates of return, illustrating the need for optimal location and crop selection for system implementation.

Capacitive deionization based on electrosorption has become a viable process for brackish water desalination. In this study, activated biochar was employed as low-cost and alternative carbon-based electrodes substituting activated carbon with comparable adsorption capacity. Effects of different activation temperatures of the biochar were studied by physical characterization (i.e. SEM, TEM, elemental analysis, and Raman spectroscopy) and electrochemical characterization (i.e. cyclic voltammetry and galvanostatic charge/discharge measurement) based on the electrical double layer theory. The highest specific capacitance obtained (118.50 F g-1) was from activated biochar electrode treated at 800°C. The removal capacity was investigated by AAS and conductivity measurements. Several limitations associated with them were identified to improve the measurements. The removal capacity of biochar electrode is ~ 2 mg g-1 with significant results for both one-sided and two-sided t-test. In summary, activated biochar can be used as a cheap-alternative electrode material for desalination based on capacitive deionization.

Yes / The implementation of Reverse Osmosis (RO) technology is noticeably increased to produce freshwater from brackish and seawater resources. In this work, performance analysis of a multistage multi pass medium-sized spiral wound brackish water RO (BWRO) desalination plant (1200 m³/day) of Arab Potash Company (APC) located in Jordan is evaluated using modelling and simulation. For this purpose, a mathematical model for the spiral wound RO process based on the principles of solution diffusion model is developed. The model is then used to simulate the operating conditions of low-salinity brackish water RO (BWRO) desalination plant. The results obtained are then compared against the real industrial data of BWRO desalination plant of APC which shows a high-level of consistency. Finally, the model is used to analysis the impact of the operating parameters such as salinity, pressure, temperature, and flow rate on the plant performance. The sensitivity analysis confirms that both feed flow rate and operating pressure as the critical parameters that positively affect the product salinity.

Yes / The Reverse Osmosis (RO) input parameters have key roles in mass transport and performance indicators. Several studies can be found in open literature. However, an experimental research on evaluating the brackish water RO input parameters influence on the performance metrics with justifying the interference between them via a robust model has not been addressed yet. This paper aims to design, construct, and experimentally evaluate the performance of a 50 m3/d RO pilot-plant to desalinate brackish water in Shahid Chamran University of Ahvaz, Iran. Water samples with various salinity ranging from 1000 to 5000 ppm were fed to a semi-permeable membrane under variable operating pressures from 5 to 13 bar. By evaluating permeate flux and brine flowrate, permeate and brine salinities, membrane water recovery, and salt rejection, some logical relations were derived. The results indicated that the performance of an RO unit is largely dependent on feed pressure and feed salinity. At a fixed feed concentration, an almost linear relationship was found to relate feed pressure and both permeate and brine flowrates. Statistically, it was found that 13 bar feed pressure results in a maximum salt rejection of 98.8% at a minimum permeate concentration of 12 ppm. Moreover, 73.3% reduction in permeate salinity and 30.8% increase in brine salinity are reported when feed pressure increases from 5 to 13 bar. Finally, it is concluded that the water transport coefficient is a function of feed pressure, salinity, and temperature, which is experimentally estimated to be 2.8552 L/(m2 h bar).