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1
Patel, Ramanbhai Motibhai. "Subirrigation with brackish water". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0020/NQ44550.pdf.
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Park, Gavin Lawrence. "Wind-powered membrane desalination of brackish water". Thesis, Heriot-Watt University, 2012. http://hdl.handle.net/10399/2532.
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This thesis presents a detailed investigation of the technical feasibility, challenges and performance issues associated with the direct-connection of a wind turbine to a membrane (wind-membrane) system for treating brackish water in remote communities. The direct-connection of these two technologies negates the reliance on energy storage in batteries, which are traditionally used, but result in reduced system efficiency and increased life-cycle costs. Furthermore, the lack of knowledge of the safe operating window in which transient operation of membrane systems is beneficial or tolerable can be addressed. The impact of wind speed fluctuations on the performance of the wind-membrane system (using a BW30-4040 membrane and feed waters of 2750 and 5500 mg/L NaCl) showed that the performance deteriorated most under fluctuations at low average wind speeds with high turbulence intensity and long periods of oscillation. Therefore, the main challenge of operating with renewable energy is not the size of the fluctuations, but the effect of the power switching off. Further examination of the impact of wind intermittency (over one hour intervals with intermittent periods from 0.5 – 3 min) showed that the increase in permeate concentration was highest at off-times < 60 s, highlighting the potential for improved performance using short-term energy buffering. The safe operating window and the key constraints to safe operation were determined for several membranes and feed water concentrations to establish the optimum operating strategy for the wind-membrane system. Supercapacitors were used to expand the safe operating window by providing energy during periods of intermittency and enhancing the power quality delivered to the membrane system by absorbing wind fluctuations. When tested over 24 hours using real wind speed data (average 6 m/s), the wind-membrane system produced 0.78 m3 of water with an average permeate concentration of 240 mg/L NaCl and average specific energy consumption (SEC) of 5.2 kWh/m3. With the addition of supercapacitor storage, the system performance improved significantly with 0.93 m3 of water produced with an average permeate concentration of 170 mg/L NaCl and SEC of 3.2 kWh/m3.
3
Hajarat, Rasha. "The use of nanofiltration membrane in desalinating brackish water". Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/the-use-of-nanofiltration-membrane-in-desalinating-brackish-water(870d69f0-073d-4474-b591-e9fe85a92af7).html.
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Harper, Grant. "Biomass-powered zero liquid discharge desalination of brackish water". Thesis, Harper, Grant (2018) Biomass-powered zero liquid discharge desalination of brackish water. Honours thesis, Murdoch University, 2018. https://researchrepository.murdoch.edu.au/id/eprint/44867/.
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Desalination is accepted as being a necessary technology to support the livelihood of communities. However, to prevent the harmful environmental impacts of brine, desalination needs to be designed with zero liquid discharge being the process rather than an afterthought. Existing approaches are often found to be inadequate and significant amounts of research into ways to prevent liquid waste are currently in place. The challenge is that the technology must be able to treat post-RO salinities (usually with high amounts of thermal energy) to be able to overcome the low heat capacities and high boiling points of saline solutions >70,000 mg/L.
This research honours project investigates a proposal developed by Enerbi Pty Ltd that incorporates heat, mechanical and electrical energy into a desalination unit that is powered by Biomass and produces a Zero Liquid Discharge product. The system was modeled in Excel and ChemCad and found to successfully produce a dry product with moderate quantities of biomass. The proposal was then modelled to treat 60ML per year under various scenarios using two particular types of Biomass, Plantation Waste, and Oil Mallee crops. These scenarios included high-value agricultural and horticultural crop scenarios using desalinated water for irrigation and salinity, with salinity problems on site being amended via saline water uptake and intervention crop planting.
The design was carried further to a Pilot Plant configuration specified using ‘off the shelf’ products, and the Pilot Plant design included upgrading the power configuration to allow for additional equipment. The Pilot Plant configuration was tested up to salinities of 85,000mg/L. It was found to successfully cope with this salinity, the most likely upper limit due to heat requirements of evaporation of hyper-saline solutions. A final concept 3D model was created to assist with placement and configuration.
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Caraballo, Ginna. "An Arduino Based Control System for a Brackish Water Desalination Plant". Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc804931/.
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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.
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Hawkins, David John. "Morphology and epidemiology of the ergasilid (Copepoda: Poecilostomatoida) parasites of British freshwater fish". Thesis, Royal Holloway, University of London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395934.
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Gigante, Bethany Marie. "SALINE ADAPTATION OF THE MICROALGA Scenedesmus dimorphus FROM FRESH WATER TO BRACKISH WATER". Cleveland State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=csu1382355969.
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Martinetti, C. Riziero. "Membrane contractor processes for desalination of brackish water reverse osmosis brines /". abstract and full text PDF (UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1455665.
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Thesis (M.S.)--University of Nevada, Reno, 2008."May, 2008." Includes bibliographical references (leaves 35-38). Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2008]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web.
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Pritchard, Mark. "Dynamics of a small tidal estuarine plume". Thesis, University of Plymouth, 2000. http://hdl.handle.net/10026.1/844.
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Small-scale estuarine plume discharges into adjacent seas are common inshore features responsible for the transportation and dispersion of brackish water in the coastal zone. However, the physics that govern small-scale mixing in the frontal regions of river plumes are still poorly understood. The current study quantified and compared the observed hydrodynamic properties present inside a radially spreading river plume discharge from the River Teign, Teignmouth, Devon, UK, to those predicted by a generic plume model. Numerical simulations designed to replicate time dependent radial plume spreading from a constant source predicted the development of an internal interfacial bore that lagged the surface plume front through radial distance and time from initial plume release. The model was scaled from time lapse X-band radar imagery that recorded several plume discharge events. Scaled model output predicted the internal bore to form approximately 180 m behind the leading surface front. Subsequent field studies employed instrumentation capable of recording high-resolution measurements of temperature, salinity and velocity, spatially and vertically throughout the plume's buoyant layer over two ebb tidal cycles. Results suggested the plume advanced at a rate dependent on a super-critical interfacial Froude number of O(1.3) and was a region of intense mixing and downward mass entrainment. Temperature contours recorded through the stratified plume gave no indication of an internal bore in its predicted position but did show an abrupt shallowing of the interfacial region some 40 to 60 m behind the surface plume front. Super-critical interfacial Froude and critical Gradient Richardson numbers present in this region of the plume implied that this was the position of the predicted bore. The form of the bore often appeared as an ensemble of undular internal hydraulic jumps rather than a singular discontinuity as predicted by the model. Bulk mixing analysis inside the leading front based on established gravity current theory suggested that the extent of turbulent exchange in the model frontal boundary condition P, was underestimated by about a factor of 2. With the required increase in P, model simulations showed a decrease in the lag distance of internal bore formation to one where critical Froude numbers were detected inside the actual plume. Throughout both surveys, the gravity head remained a reasonably constant size due to any increase in across frontal velocity over the ebb tidal cycle being matched by an increase in entrainment and mixing. The subsequent conclusions from the study show the outflow and mixing dynamics are controlled by the estuary's tidal modulation of estuarine brackish water outflow / plume inflow rate behind the leading plume frontal discontinuity.
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Jones, Michael A. "Systems Modeling and Economic Analysis of Photovoltaic (PV) Powered Water Pumping Brackish Water Desalination for Agriculture". DigitalCommons@USU, 2015. https://digitalcommons.usu.edu/etd/4265.
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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.
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Brown, Christopher J. "Planning decision framework for brackish water aquifer, storage and recovery (ASR) projects". [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0013031.
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Ferronato, Chiara <1984>. "Water, sediment and soil physicochemical interactions in freshwater, brackish and saline systems". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6881/.
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The physicochemical interactions between water, sediment and soil deeply influence the formation and development of the ecosystem. In this research, different freshwater, brackish and saline subaqueous environments of Northern Italy were chosen as study area to investigate the physicochemical processes which occur at the interface between water and sediments, as well as the effects of soil submergence on ecosystem development.
In the freshwater system of the Reno river basin, the main purpose was to define the heavy metals hazard in water and sediments of natural and artificial water courses. Heavy metals partitioning and speciation allowed to assess the environmental risk linked to the critical action of dredging canal sediments, for the maintenance of the hydraulic safety of plain lands. In addition, some bioremediation techniques were experimented for protecting sediments from heavy metals contamination, and for giving an answer to the problem of sediments management.
In the brackish system of S. Vitale park, the development of hydromorphic and subaqueous soils was investigated. The study of soil profiles highlighted the presence of a soil continuum among pedons subjected to different saturation degrees. This investigation allowed to the identification of both morphological and physicochemical indicators, which characterize the formation of subaqueous soils and describe the soil hydromorphism in transitional soil systems.
In the saline system of Grado lagoon, an ecosystem approach was used to define the role of water oscillation in soil characterization and plants colonization. This study highlighted the close relationship and the mutual influence of soil submergence and aeration, tide oscillation and vegetation cover, on the soil development. In view of climate change, this study contribute to understand and suppose how soil and landscape could evolve. However, a complete evaluation of hydromorphic soil functionality will be achieved only involving physiological and biochemical expertise in these kind of studies.
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Dahlgren, Kristin. "Food web structures and carbon transfer efficiencies in a brackish water ecosystem". Doctoral thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-38014.
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Two differently structured food webs can be distinguished in the pelagic habitat of aquatic systems; the classical one (autotrophic) with phytoplankton as a base and the microbial food web (heterotrophic) with bacteria as a base. Energy (produced at the basal trophic level) reaches higher trophic levels, i.e. zooplankton, directly in the classical food web in contrast to the microbial food web where it passes through additional trophic levels before reaching zooplankton. Energy is lost between each trophic level and therefore less energy should reach higher trophic levels in the microbial food web than in the classical food web. However, factors such as edibility of prey, temperature and properties of the predator, might also influence the food web structures and functions. In this thesis I studied which factors are important for an efficient carbon transfer and how a potential climate change might alter the food web efficiency in pelagic and pelagic-benthic food webs in the Baltic Sea. Furthermore, one of the most dominant zooplankton in the northern Baltic Sea, Limnocalanus macrurus, was studied in order to establish the seasonal pattern of lipid reserves in relation to food consumption. My studies showed that the carbon transfer efficiency during summer was not directly connected to the basal production, but factors such as the ratio between heterotrophs and autotrophs, the relationship between cladocerans and calanoid copepods and the size and community structure of both phytoplankton and zooplankton were important for the carbon transfer efficiency. In a climate change perspective, the temperature as well as the relative importance of the microbial food web is likely to increase. A temperature increase may have a positive effect on the pelagic food web efficiency, whereas increasing heterotrophy will have a negative effect on the pelagic and pelagic-benthic food web efficiency, reduce the fatty acid content of zooplankton and reduce the individual weight of both zooplankton and the benthic amphipod Monoporeia affinis. During the seasonal study on the calanoid copepod L. macrurus, I found that this species is mainly a carnivore, feeding on mesozooplankton during most of the year but switches to feeding on phytoplankton when these are abundant. Furthermore, when food is scarce, it utilizes lipids that are built up during the course of the year. From these studies I can draw some major conclusions; there are many factors that influence how efficient carbon is transferred in the food web and different factors are probably of various importance in different areas. In order to determine the carbon transfer efficiency, the various strategies exerted by different organism groups have to be considered, as for example that some zooplankton utilize lipid reserves instead of feeding all year around. Also, in a climate change perspective, the pelagic-benthic food web efficiency will decrease, as will the quality of zooplankton and M. affinis, possibly having implications for higher trophic levels such as fish.
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Al-Ghawas, Samir A. "Some fertility problems associated with Kuwaiti calcareous soil and brackish irrigation water". Thesis, Bangor University, 1994. https://research.bangor.ac.uk/portal/en/theses/some-fertility-problems-associated-with-kuwaiti-calcareous-soil-and-brackish-irrigation-water(d3c74d9d-cf4e-452a-8c2c-73d98636cffe).html.
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The study was undertaken to improve phosphorus (P), iron (Fe), zinc (Zn) and manganese (Mn) availability and crop uptake in Kuwaiti calcareous soils. Field, glass-house and laboratory studies investigated the effectiveness of i) pyrophosphate (PP) mixed with orthophosphate (OP) fertilizers and ii) elemental sulphur (S') as a soil acidulent. In the field PP was incorporated with OP at a PP: OP P ratio of 0: 100,5: 95 and 10: 90 and applied at recommended agronomic P rates to Zea mays (corn) and Triticum spp (wheat) with micronutrients as subtreatments. Crop yields did not differ for all treatments receiving P probably due to high P residual levels in the soil but plant P uptake and P-tissue concentrations were significantly higher with PP treatment and Zn-tissue concentrations increased above the control treatments by 17% and 34% for the corn and wheat respectively, whereas with OP only treatments there was a slight decline in Zntissue concentrations. A further two experiments were conducted in the glass-house utilising a similar soil and experimental design to grow Zea mays and Avena sativa (oat) under distilled or brackish water irrigation regimes. PP amended treatments increased plant yields in the glass-house experiments by 15-18% and 20-25% for the corn and oats, respectively, while plant P-uptake increased by 83% and 32% when PP was incorporated with OP for the corn and oats respectively. Similarly, PP treatments stimulated higher plant Zn-uptake. In the glass-house Zn concentrations in plant tissues were higher by 24-40% for treatments with PP than with OP only. These findings were supported by NaHC03 P and DTPA-Zn soil extraction, where levels moved from "marginal" to "adequate" ranges with the inclusion of PP with OP. Generally there were no significant improvements when PP/OP ratio increased from 5 to 10%. Furthermore, brackish water irrigation had no direct influence on PP soil reaction or hydrolysis. Elemental sulphur (S') was applied in quantities that could theoretically neutralise 0,25,50,100 and 200% of the soil CaCO3 with two rates of P and micronutrient combinations in a split-split plot design. In the field experiment corn and wheat were grown as test crops, while in the glass-house corn was grown with distilled or brackish water after the soil/S' mixture was incubated at 30'C and approximate field moisture capacity for six months. The oxidation of S' to H 2SO4 did not proceed in a linear fashion; there were lower rates of S' oxidation at the high S' application, better monitored by the generated SO42 than the decline in either soil pH or CaCO3 content. Soil pH decline was moderate until soil CaCO3 content dipped below 6%. At these levels soils became acidic. The dissolution of soil CaCO3 was proportional to the S' applied, but its effective size distribution changed from coarse clay/fine silt to that of coarse silt/fine sand with the highest S' rates. This would have profound effects on its surface area and activity. The S' treatment also resulted in higher soil salinity; EC increased from 3-4 to as high as 12 dSm-1. Simultaneously there was a build up of gypsum which under SEM examination revealed that soil particle surfaces were shielded by gypsum crystals. Plants did not respond favourably to S' inclusion, and yield declined by 35% with the highest S' rates. However, at moderate rates the yield was similar to the control. Soil-P increased (NaHCO3 P extraction) at moderate levels of S' and then declined at higher rates. Extractable soil-Fe (DTPA) significantly increased only at higher S' rates, while Zn (DTPA) did not have a clear response and DTPA-Mn steadily increased even with the lowest S' rate. Plant tissue concentration and element uptake were difficult to assess in the light of declining plant growth and changed soil nutrient availability. Nevertheless S' treatment equivalent to 25% CaCO3 neutralisation maintained yield, P and Zn uptake while significantly increasing Fe and Mn uptake by 63 and 12% respectively for the field grown wheat. In none of the studies was there consistent response to micronutrient fertilisation. Furthermore, brackish irrigation did not interfere with the soil nutrient extractions or plant uptake.
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Wright, Natasha C. (Natasha Catherine). "Design of cost-optimized village-scale electrodialysis systems for brackish water desalination". Thesis, Massachusetts Institute of Technology, 2018. https://hdl.handle.net/1721.1/122204.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2018Cataloged from PDF version of thesis.
Includes bibliographical references.
This thesis proposes methods of reducing the cost of electrodialysis brackish water desalination systems, specifically for use in rural India, where 60% of the groundwater is too saline to drink. Convergence of socioeconomic and technical factors led to the insight that photovoltaic (PV) powered electrodialysis (ED) has the potential for impact in rural water treatment. In order to design a system that can meet the necessary production requirements, a robust parametric model was created to predict the desalination rate, limiting current density, and total energy use in an ED system. The model agrees with experimental measurements across two diverse ED stack designs, differing in total membrane area, membrane manufacturers, and flow channel spacers. A commercial-scale ED stack was additionally tested in Chelluru, India, building confidence that the model is predictive for real groundwater, and that ED systems are feasible to operate in the rural Indian context.
The ED model was used within an optimization routine to determine the lowest cost operating mode and stack design, assuming existing, flat-stack architectures. Common operating modes including constant-voltage batch and multi-stage continuous systems were considered alongside novel operation modes including voltage-regulated batch and hybrid batch-continuous systems. For the production and desalination rates required for a village-scale application, a voltage-regulated hybrid system that is fully optimized for membrane width, length, and channel thickness reduces the 10-year total cost and capital cost of the system by 37% and 47%, respectively, in comparison to a commercially available stack optimized under the same operation modes. While matching of applied and limiting current densities can be achieved using a voltage-regulated batch operation (minimizing stack cost), this requires a potentially costly DC power supply and control system.
The final part of the thesis proposes a spiral ED stack architecture that allows for matching through the geometry of the stack alone. Both a standard Archimedean spiral and an ideal irregular spiral shape are presented. The ideal spiral shape would reduce the 10-year total cost and capital cost by 21% and 39%, respectively, in comparison to the Archimedean spiral, and is cost-competitive with a hybrid voltage-regulated flat-stack design.
by Natasha C. Wright.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Mechanical Engineering
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Pine, Harvey J. Boyd Claude E. "Investigations of brackish water aquaculture in the Blackland Prairie region of Western Alabama". Auburn, Ala, 2008. http://hdl.handle.net/10415/1455.
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Mustafa, Akhmad Biological Earth & Environmental Sciences Faculty of Science UNSW. "Improving acid sulfate soils for brackish water aquaculture ponds in South Sulawesi, Indonesia". Awarded by:University of New South Wales. Biological, Earth & Environmental Sciences, 2007. http://handle.unsw.edu.au/1959.4/40619.
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Brackish water aquaculture is one of the largest coastal industries in Indonesia. This farming system involves the construction of ponds m coastal sediments. Many ponds in Indonesia have been abandoned due to past development of ponds in acid 8ulfate soils (ASS); these soils produce sulfuric acid through the oxidation of pyrite du ring and after the sediments have been excavated. The soils also contain elevated concentrations of metal such as iron and aluminium which are harmful to farmed fish and shrimp. Acidification of pond soil causes recurrent fish and shrimp mortalities, poor growth rate in fish and shrimp, soft shell syndrome in shrimp and low plankton densities, Pond maintenance costs in ASS are also significantly higher than non-ASS ponds. There are over 6.7 million ha of ASS In Indonesia of which 35% has been developed for brackish water aquaculture. This study developed and trialled methods of soil remediation to restore abandoned ASS-affected ponds. The main objective was to develop methods at remediation that were scientifically sound but also practical and inexpensive for farmers. The research involved characterising, in detail, the chemical and physical properties of ponds soil followed by laboratory-based experiments to improve soil properties. The results of laboratory trials were the basis for large-scale field experiments to test soil remediation strategies. The study showed that pond bottoms could be improved by forced oxidation, flooding and water exchange followed by Iiming and fertilising. Up to 500% increases in productivity were achieved by this method and soils conditions Improved significantly. A further twofold productivity increase was achieved by an integrated liming method in which lime is added to rebuilt or new dykes in layers. A juvenile shrimp production system was developed for ponds that were too severely degraded or costly to remediate. The research developed methods of preventing metal toxicity in Juvenile shrimp. The study showed that aquaculture ponds built in ASS could be remediated and returned to viable production systems. Importantly, the study has developed a more detailed understanding of chemical properties In ASS-affected ponds.
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Ali, Wael [Verfasser], e Jochen S. [Akademischer Betreuer] Gutmann. "Brackish water desalination via stimuli-responsive polymeric hydrogels / Wael Ali ; Betreuer: Jochen S. Gutmann". Duisburg, 2019. http://d-nb.info/1200352890/34.
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Sakamoto, Kentaro. "STUDIES ON THE CELLULOSE DECOMPOSING ABILITY OF JAPANESE COMMON BRACKISH-WATER CLAM "Corbicula japonica". Kyoto University, 2009. http://hdl.handle.net/2433/123976.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第14664号
農博第1746号
新制||農||968(附属図書館)
学位論文||H21||N4437(農学部図書室)
UT51-2009-D376
京都大学大学院農学研究科応用生物科学専攻
(主査)准教授 豊原 治彦, 教授 松井 徹, 准教授 笠井 亮秀
学位規則第4条第1項該当
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Tucakovic, Ivana. "An automated blending device for brackish water desalination: Upscaling the laboratory-scale device for standardised water supply on farms". Thesis, Tucakovic, Ivana (2020) An automated blending device for brackish water desalination: Upscaling the laboratory-scale device for standardised water supply on farms. Honours thesis, Murdoch University, 2020. https://researchrepository.murdoch.edu.au/id/eprint/57272/.
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Farmers in many places across Australia are facing drought, with dryland salinity in Western Australia one of the biggest concerns in the rural Wheatbelt farming industry. This project seeks to address the salinity issue and how to improve groundwater consumption while still providing suitable quality water for diverse farming needs.
The method investigated and used to solve this issue is the automation of a blending device with a solar PV-powered brackish water desalination unit by reverse osmosis membrane (PVRO). The plant used brackish water provided from the borewell on the farm at Muresk Institute near the Wheatbelt town of Northam and permeate water from the PVRO device. The selection switch can be used to blend different concentrations of total dissolved solids (TDS) to suit different on farm requirements. Water with different TDS concentrations can be used to either water the crops, distribute to the cattle or be used for domestic purposes.
In this study, data is presented to show that Solar PVRO permeate and brackish water can be automatically blended using the Arduino platform. The equipment used is listed in the Materials and Methods chapter and is utilised to give the best possible results within the budget constraints.
The possibility of having the blending unit would aid many farmers as it would promote more extensive use of the brackish water. Likewise, the blending unit will improve the long life of the RO membranes by not using RO as much. The unit is portable and moved easily to the required location.
By assisting the user in controlling the quality, the system can reduce the energy required in running the PVRO module by around 10 MW per year with savings of around $300 per year. More detail can be seen in Table 8.
This piece of equipment can assist not just farmers but regional communities with their basic water needs. The blending unit can decrease the RO water processed by around 34 %. This means that there is a water-saving of 170 L per hour, assuming the RO unit operates for five and a half hours per day. Additionally, total savings per year is around $1,069, including the earnings from electricity sell back. The important thing to note is that in this case, assumptions were that feed water is around 2,000 ppm, and the desired quality is 900 ppm. In another case, cost-saving would be different, as well as water savings.
In regard to membrane life expectancy, most manufacturers document the typical RO membrane to have a life expectancy of approximately seven years, in normal operation. Due to the 36 % reduction of permeate water, from the inclusion of the blending unit, an additional estimated 11.62 years of life expectancy can be gained to the RO membrane.
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Tharamapalan, Jayapregasham. "Application and Optimization of Membrane Processes Treating Brackish and Surficial Groundwater for Potable Water Production". Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5530.
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The research presented in this dissertation provides the results of a comprehensive assessment of the water treatment requirements for the City of Sarasota. The City's drinking water supply originates from two sources: (1) brackish groundwater from the Downtown well field, and (2) Floridan surficial groundwater from the City's Verna well field. At the time the study was initiated, the City treated the brackish water supply using a reverse osmosis process that relied on sulfuric acid for pH adjustment as a pretreatment method. The Verna supply was aerated at the well field before transfer to the City's water treatment facility, either for softening using an ion exchange process, or for final blending before supply. For the first phase of the study to evaluate whether the City can operate its brackish groundwater RO process without acid pretreatment, a three-step approach was undertaken that involved: (1) pilot testing the plan to reduce the dependence on acid, (2) implementing the plan on the full-scale system with conservative pH increments, and (3) continuous screening for scale formation potential by means of a “canary” monitoring device. Implementation of the study was successful and the annual savings in operating expenditure to the City is projected to be about $120,000. From the acid elimination study, using the relationship between electrical conductivity in water and total dissolved solids in water samples tested, a dynamic approach to evaluate the performance of the reverse osmosis plant was developed. This trending approach uses the mass transfer coefficient principles of the Homogeneous Solution Diffusion Model. Empirical models were also developed to predict mass transfer coefficients for solutes in terms of total dissolved solids and sodium. In the second phase of the study, the use of nanofiltration technology to treat aerated Verna well field water was investigated. The goal was to replace the City's existing ion exchange process for the removal of hardness and total dissolved solids. Different pretreatment options were evaluated for the nanofiltration pilot to remove colloidal sulfur formed during pre-aeration of the groundwater. Sandfilters and ultrafiltration technology were evaluated as pretreatment. The sandfilter was inadequate as a pre-screen to the nanofiltration pilot. The ultrafiltration pilot (with and without a sandfilter as a pre-screen) proved to be an adequate pretreatment to remove particulates and colloids, especially the sulfur colloids in the surficial groundwater source. The nanofiltration pilot, was shown to be an efficient softening process for the Verna well field water, but it was impacted by biofoulants like algae. The algae growth was downstream of the ultrafiltration process, and so chlorination was used in the feed stream of the ultrafiltration process with dechlorination in the nanofiltration feed stream using excess bisulfite to achieve stable operations. Non-phosphonate based scale inhibitors were also used to reduce the availability of nutrients for biofilm growth on the nanofiltration membranes. The combined ultrafiltration-nanofiltration option for treatment of the highly fouling Verna water samples is feasible with chlorination (to control biofouling) and subsequent dechlorination. Alternatively, the study has shown that the City can also more economically and more reliably use ultrafiltration technology to filter all water from its Verna well field and use its current ion exchange process for removal of excess hardness in the water that it supplies.Ph.D.
Doctorate
Civil, Environmental, and Construction Engineering
Engineering and Computer Science
Environmental Engineering
22
Allen, Nancy J. "Computation of pseudosonic logs in shallow fresh/brackish water wells: a test case in Brunswick, Georgia". Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/44105.
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Due to the usefulness of sonic logs in formation evaluation, efforts have been made to develop a method for calculating pseudosonic logs for wells in which sonic logs were not originally obtained. These efforts attempt to use electrical resistivity data in the calculation of pseudosonic logs by means of empirical scale functions. The purpose of this study is to examine ways of applying these relationships in relatively shallow wells where the principal formation fluid is fresh or brackish water. Data from four wells situated in Brunswick, Georgia were used in this study.
Conventional focused resistivity logs are sensitive to beds as thin as one foot and can provide detail similar to that seen on sonic logs. Focused resistivity logs should be best for conversion to pseudosonic logs in shallow wells, where invasion is minimal and the water used for drilling fluid has electrical resistivity close to that of formation water. Sonic and resistivity logs from a representative well are needed in the procedure for finding an empirical relationship between sonic transit time and resistivity. Values of transit time plotted versus resistivity are read from corresponding depths on both types of logs. The graphs obtained in this study reveal significantly more scatter than previously published graphs based upon deep well data.
An important feature clearly evident in the graphs is the presence of groups of points which me offset from each other. A separate scale function relating transit time and resistivity can be obtained from each group of points. It is noted that the different groups correspond to differences ir1 the chlorinity of the formation water. The results of this study indicate that it is necessary to consider the salinity of the formation water as well as electrical resistivity for purposes of calculating pseudosonic logs. In previous studies three constant coefficients were deterrnined experimentally in order to obtain an empirical scale function. The present study suggests that it may be possible to replace these constants with chlorinity dependent coefficients. The final results of this study indicate that reasonably reliable pseudosonic logs can be obtained only by using high quality focused resistivity logs from wells where information about the salinity of the formation water is also available.
Master of Science
23
Valdes-Abellan, Javier. "Study of impacts on the vadose zone deriving from use of brackish inland aquifers desalted water". Doctoral thesis, Universidad de Alicante, 2013. http://hdl.handle.net/10045/84087.
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El uso de agua desalada en agricultura es una actividad cada vez más extendida, debido a la disminución de los recursos convencionales y al aumento de eficiencia de los procesos de desalación. La desalación no se limita ya únicamente al agua de mar, en los últimos tiempos está aumentando la desalación de agua procedente de acuíferos salinos continentales. El objetivo principal de esta tesis es evaluar el impacto que el uso prolongado de esta agua puede tener sobre la zona no saturada del terreno y sus propiedades hidráulicas. En el marco de este trabajo se ha establecido una parcela experimental en el campus de la Universidad de Alicante donde se han cultivado especies cespitosas regadas con agua desalada procedente del acuífero salobre continental de San Vicente del Raspeig. La gestión de la parcela se ha realizado según prácticas habituales realizadas en la zona. Se ha llevado un control del contenido de agua y succión del terreno durante un periodo de 20 meses, bajo dos sistemas de monitorización alternativos: uno manual y otro automático. La experiencia ha sido completada con un ensayo de trazador mediante el empleo de BrLi controlado durante un periodo de 160 días. Asimismo, se ha realizado en laboratorio la caracterización hidráulica de muestras extraídas de la propia parcela experimental. A partir de los datos adquiridos, de manera manual y automática, se ha elaborado un modelo de flujo con el programa HYDRUS 1D para cada una de los sets de datos, el cual se ha calibrado y validado para diferentes periodos. Por otro lado, el ensayo de trazador (transporte conservativo), también simulado mediante HYDRUS 1D, además de validar el modelo de flujo, ha permitido derivar parámetros de transporte (dispersividad) a escala de campo. Finalmente, se ha creado un modelo predictivo de transporte de masa reactivo que implementa procesos geoquímicos y cambios asociados en los parámetros hidráulicos de la zona no saturada, para largos periodos de tiempo (30 años). Este último modelo se elaboró mediante la aplicación HP1, que combina los códigos HYDRUS 1D y PHREEQC. Además del modelo predictivo bajo las condiciones actuales, otros tres escenarios, según varios criterios, han sido considerados. Los dos modelos de flujo resultantes, a partir de datos adquiridos manualmente y automáticamente, han descrito adecuadamente la dinámica del flujo en la zona no saturada, concluyendo que ambas estrategias son válidas para obtener tendencias generales del flujo. No obstante, la estrategia automática es más adecuada para detectar posibles cambios en las propiedades hidráulicas debido a su mayor sensibilidad y frecuencia en la toma de datos. Para la obtención de parámetros de transporte, la combinación en el ensayo de trazador de la determinación de Br total mediante rayos X, junto con la parametrización por método inverso, ha resultado ser un método rápido y fiable. Los modelos predictivos han puesto de manifiesto un proceso de disolución continuo del yeso contenido en el suelo, así como procesos de disolución (en la zona radicular) y posterior precipitación (bajo ésta) de la calcita en el terreno. Los resultados de la simulación indican cambios en la porosidad que supondrán cambios de conductividad hidráulica en un factor mayor de 2. Finalmente, el estudio de los diferentes escenarios resalta que: la ausencia de riego reduce los cambios esperados en el terreno; la ausencia de yeso en el terreno producirá una reducción de la conductividad hidráulica bajo la zona radicular; y la disminución de la presión parcial de CO2 en la zona radicular disminuye drásticamente las disoluciones de las especies carbonatadas participantes.
24
Tshuma, Ivonne. "Brackish water treatment using pressure retarded osmosis (PRO) as a driving force for reverse osmosis (RO)". Thesis, Tshuma, Ivonne (2021) Brackish water treatment using pressure retarded osmosis (PRO) as a driving force for reverse osmosis (RO). PhD thesis, Murdoch University, 2021. https://researchrepository.murdoch.edu.au/id/eprint/61548/.
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The desalination process removes salts and contaminants from water to make it suitable for drinking and other beneficial purposes. Although Reverse Osmosis (RO) is currently the most energy-efficient, widely used desalination technology, it still requires a great deal of energy to create the high pressure necessary to desalinate seawater. The largest operating cost is the energy consumed in overcoming osmotic pressure and membrane resistance. Pressure Retarded Osmosis (PRO), on the other hand, utilises the salinity gradient between two solutions of different salt content to produce pressure, which can subsequently be used to generate electrical energy.
This thesis describes how PRO can be used directly as the sole energy source for RO in an autonomous PRO-RO system without additional energy input without converting osmotic energy into electrical energy. The PRO-RO proof of concept was experimentally verified in a simple combined cell without cross-flow resulting in 12.5 bars of hydraulic pressure, and flux of 3.5 L m-2 hr-1 in the RO permeate. The PRO-RO system used PRO and RO brackish water feed solution and concentrated brine PRO draw solution (200 g/L NaCl).
PRO is typically driven by freshwater to seawater gradient, but far greater energy can be predicted using hypersaline draw solutions. This study investigates the power density and maximum flux obtainable from two such saltwater solutions. The experimental data was verified by a transient model that predicts well (within 10%) PRO flux for all draw solution concentrations coupled with deionised water as feed. However, lower agreement with laboratory results was found for draw concentrations above 100 g/L when coupled with salty feed. Draw and feed cross-flow velocity were optimised at 0.1 m/s and 0.17 m/s, respectively.
A cellulose tri-acetate forward osmosis membrane was used for experimental evaluation of power production by a PRO apparatus with pressure generation up to 40 bars. A numerical model was produced from the first principles and established theory on osmotic systems to aid understanding and project beyond the practical experimental results.
The concept of combining the PRO driven by hypersaline and brackish water with a brackish water RO was investigated by modelling and simple proof of concept experiments. Theory suggests that the energy recovered from a PRO system keeps increasing with the draw solution's salt concentration. However, draw concentrations above 150 g/L did not result in a further increase in observed flux and observed energy (with a maximum pressure of 40 bars). Despite no gain in flux, modelled optimal power densities of 1.29, 12.19, and 62.4 W/m2 were obtained with increasing draw solution concentrations of 70, 150, and 300 g/L, respectively, with seawater feed solutions.
A novel, autonomous pressure retarded osmosis (PRO) driven reverse osmosis (RO), with an energy recovery device (ERD), was proposed to replace RO high-pressure pumps. The experimental PRO power density outputs from seawater/brackish water feed with 300 g/L draw and RO power density requirements were analysed. Coupling PRO with RO at PRO maximum power densities was found not to be economically viable due to high pressures of 160 bars.
The power density of 19.1 W/m2, achieved with brackish (10 g/L) feed and 300g/L draw, was sufficient to desalinate brackish water by RO at 30 bar pressure. Overall, brackish water feed and 300 g/L draw solution were used to model direct PRO to RO coupling efficacy. Using these feed and draw concentrations and the projected fluxes using currently available membranes, direct PRO to RO coupling of 2 m2 of PRO membrane to 1 m2 of RO membrane would produce 12.4 L m2 hr-1 of RO permeate at 30 bar applied pressure in an autonomous PRO-RO system.
25
Hofman, Birgitta. "Effect of advective pore water flow on degradation of organic matter in permeable sandy sediment : - A study of fresh- and brackish water". Thesis, Linköping University, Department of Thematic Studies, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-3376.
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The carbon metabolism in costal sediments is of major importance for the global carbon cycle. Costal sediments are also subjected to physical forcing generating water fluxes above and through the sediments, but how the physical affect the carbon metabolism is currently poorly known. In this study, the effect of advective pore water flow on degradation of organic matter in permeable sandy sediment was investigated in a laboratory study during wintertime. Sediments were collected from both brackish water (Askö) and from a fresh water stream (Getå Stream). In two chamber experiments, with and without advective pore water flow, the degradation of organic matter was measured through carbon dioxide analysis from water and headspace. In Askö sediments mineralization rates ranged from 3.019 - 5.115 mmol C m-2 d-1 and 3.139 mmol C m-2 d-1 with and without advective pore water flow, respectively. Those results correspond with results from earlier studies of carbon mineralization rates in sediment in the North Sea and the Baltic Sea. There were no significant differences between the two groups in the Askö sediment. In Getå Stream sediments mineralization rates ranged between 4.059 mmol C m-2 d-1 and 6.806 mmol C m-2 d-1 with and without advective flow, respectively. The mineralization rates for Getå Stream correspond with earlier studies of carbon mineralization rates in a stream in New Hampshire.
26
Tran, Thanh Be, of Western Sydney Hawkesbury University, Faculty of Agriculture and Horticulture e School of Agriculture and Rural Development. "Sustainability of rice-shrimp farming system in a brackish water area in the Mekong Delta of Vietnam". THESIS_FAH_ARD_Tran_T.xml, 1994. http://handle.uws.edu.au:8081/1959.7/421.
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The Mekong Delta, which is considered as the main 'rice bowl and fish basket', is one of seven distinct agro-ecological regions of Vietnam and plays an important role in the economy of the country. Several rice-based farming systems have been developed in various areas of the MD. Rice-shrimp integrated system in brackish areas is a special farming system developed in this delta. It is a profitable system and seems to be environmentally safe on the one hand without the use of pesticides. On the other hand, use of brackish water in this system may result in degradation of land, as some previous studies have found. To understand how this farming system works and to identify the external and internal factors influencing its sustainability, the project 'Sustainability of rice-shrimp farming system in a brackish area in the Mekong delta of Vietnam' was carried out in 1992-1993 by an interdisciplinary team of researchers from the University of Cantho and staff of local district Agricultural Office, representing different fields of sciences. The research methodology was the Farming Systems Research approach with modifications towards soft systems thinking, involving farmers into the research process. One main result of this study is an insight into the rice-shrimp farming system. It includes various physical, biological, technological, economical and sociological aspects of rice production prior to integration and in integrated farm, naturally supplied shrimp growing and giant shrimp rearing, upland crop production as well as off-farm and non-farm work of farm households. Sustainability of the system studied is assessed, in comparison with rice monoculture, through various criteria of the three view points productivity, environmental safety and socio-economic effectiveness. In terms of such points of view, rice-shrimp farming system is rated higher than rice monoculture system. Thus the integrated system so far is considered to be more sustainable than the others.Master of Science (Hons)
27
Qiu, Tianyu. "Desalination of brackish water by a batch reverse osmosis desalink system for use with solar thermal energy". Thesis, Aston University, 2014. http://publications.aston.ac.uk/24333/.
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For remote, semi-arid areas, brackish groundwater (BW) desalination powered by solar energy may serve as the most technically and economically viable means to alleviate the water stresses. For such systems, high recovery ratio is desired because of the technical and economical difficulties of concentrate management. It has been demonstrated that the current, conventional solar reverse osmosis (RO) desalination can be improved by 40–200 times by eliminating unnecessary energy losses. In this work, a batch-RO system that can be powered by a thermal Rankine cycle has been developed. By directly recycling high pressure concentrates and by using a linkage connection to provide increasing feed pressures, the batch-RO has been shown to achieve a 70% saving in energy consumption compared to a continuous single-stage RO system. Theoretical investigations on the mass transfer phenomena, including dispersion and concentration polarization, have been carried out to complement and to guide experimental efforts. The performance evaluation of the batch-RO system, named DesaLink, has been based on extensive experimental tests performed upon it. Operating DesaLink using compressed air as power supply under laboratory conditions, a freshwater production of approximately 300 litres per day was recorded with a concentration of around 350 ppm, whilst the feed water had a concentration range of 2500–4500 ppm; the corresponding linkage efficiency was around 40%. In the computational aspect, simulation models have been developed and validated for each of the subsystems of DesaLink, upon which an integrated model has been realised for the whole system. The models, both the subsystem ones and the integrated one, have been demonstrated to predict accurately the system performance under specific operational conditions. A simulation case study has been performed using the developed model. Simulation results indicate that the system can be expected to achieve a water production of 200 m3 per year by using a widely available evacuated tube solar collector having an area of only 2 m2. This freshwater production would satisfy the drinking water needs of 163 habitants in the Rajasthan region, the area for which the case study was performed.
28
Malek, Payam. "Clean water from clean energy : removal of dissolved contaminants from brackish groundwater using wind energy powered electrodialysis". Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/11727.
Texto completo da fonteResumo:
Around 770 million people lack access to improved drinking water sources (WHO 2013), urgently necessitating implementation of contaminant removal by e.g. desalination systems on a large scale. To improve water quality and enable use of brackish water sources for human consumption in remote arid areas, a directly coupled wind – electrodialysis system (Wind-ED) was developed. Modularity, sustainability and above all suitability for the practical use in off-grid locations were the main motivations and design objectives. The direct coupling of wind energy with membranes reduces the system costs as well as technical drawbacks associated with using intermediate energy storage systems. During this research, systematic experiments were performed using the Wind-ED system in order to determine desalination performance and clean water production, specific energy consumption (SEC) and current efficiency (ηc) under relevant conditions, such as varying: i) wind speed, ii) wind turbulence intensity, iii) oscillation periods, iv) varying NaCl concentrations and v) flow rates. Moreover, the competitive removal of four commonly available inorganic contaminants in brackish groundwater sources, nitrate (NO3-), fluoride (F-), sulphate (SO42-) and chloride (Cl-), were investigated. Firstly, to establish a systematic understanding of how and to what extent energy fluctuations influence the transport of the salt (i.e. NaCl) ions across the membranes, experiments were conducted using pulsed electric field assisted electrodialysis (pulsed-ED) over a wide range of frequencies (0.001 – 10 Hz) and duty cycles (20 – 80). The results showed that pulsation applied in the sub-limiting regime resulted in reduced water production, explained by the delays caused by the off-periods during the pulsed desalination process. At higher current densities, pulsation led to considerable improvements in current (e.g. up to 95%, for a feed solution of 500 mg/L and a pulse regime of 1 Hz at 50 V peak voltage) and significant reduction in water dissociation, explained by a reduction of concentration polarisation. Importantly, the pulsation had no significant effect on energy consumption or current efficiency suggesting that ED could be suitable for direct coupling to fluctuating energy sources such as wind energy. ED was consequently coupled to a wind turbine system and a series of desalination tests were performed over a wide range of wind speeds (2-10 m/s), turbulence intensities (TI of 0-0.6) and oscillation periods (0-180 s). Results showed that water production and SEC increased with wind speed. However, both the water production and SEC stopped increasing as the power output from the turbine levelled off at wind speeds above the rated value (vrated: 7.9 – 8.4 m/s). The impact of wind speed fluctuations on the system performance were insignificant up to a TI of 0.4. The desalination performance declined under high turbulence intensity fluctuations (TIs ≥ 0.5) and long periods of oscillation (> 40 s), as the wind-ED system periodically cycled off in response to operation below the cut-in wind speed of the wind turbine (vcut-in: ~ 2 m/s). The off-cycling of the system caused significant delays in the desalination process, and thus resulted in reduced water production. Further reduction in the water production resulted as the wind-ED system operated under intermittent wind speed conditions with off-wind periods longer than 10 s. It was concluded that the main challenge in direct coupling of ED to a wind resource was not the magnitude of the fluctuations but the impact of the power cycling off during long periods of oscillation and lengthy periods of no wind. Interestingly, the SEC of the process remained relatively unaffected by the fluctuations and intermittencies in the wind resource. The effect of energy fluctuations on the competitive transport of F-, Cl-, NO3- and SO42- from artificial brackish water (TDS ~4350 mg/L) was investigated using different sets of real wind data. The ion removal, independent of the wind regime tested, followed the order: NO3- ≥ Cl- > F- > SO42-. The competitive removal of the ions was linked to differences in physicochemical properties (i.e. hydration energy, ionic mobility and valence). The specific selectivity (e.g. preferential transport of NO3- over SO42- ions) was found to increase with concentration polarisation being either minimised (by lowering the mean wind speed) or disrupted (by fluctuations in the wind resource). The results from flow rate and feed concentration experiments, showed that power production of the wind turbine depended on not only the available wind energy but also the resistance of the load (i.e. the ED stack). Thus, increasing the feed concentration and the flow rate resulted in reduced resistance in the ED stack (Rstack), which inversely influenced the current induction counter torque force applied on the shaft of the wind turbine and caused the rotor to spin at a lower angular velocity. This led to increased sensitivity of the wind-ED system to wind speed fluctuations (e.g. system cycled off due to extreme fluctuations and intermittencies with low TDS feed concentration of 2400 mg/L) and hence a reduction of desalination performance. Impact of flow rate on the SEC was found to be negligible; this was attributed to the automatic voltage to current adjustments done by the wind turbine, in order to minimise the impacts of Rstack on the power production by the turbine at a given wind speed. Increased flow rate and resulting shrinkage of the boundary layer’s thickness, caused the concentration profiles at the solution-membrane interface to become steeper. This favoured the transport of ions with the highest diffusion coefficients in the mixture (i.e. Cl- and NO3-). Decreased flow rate favoured the transport of ions with larger valence numbers and higher electric mobility inside the electrolyte (i.e. SO42-); as the former property governed the faster migration of SO42- ions through the thick boundary layer and the latter property assisted with the improved affinity of the ion-exchange membrane to SO42- ions compared to the monovalent anions in the mixture. Increasing the feed concentration of Cl- from 500 to 2,550 mg/L led to reduced transport numbers for the other anions in the mixture and significantly reducing their removal rate. The results obtained from both the pulsed-ED and wind-ED experiments showed that, despite direct coupling to the fluctuating energy source the SEC of the process remained relatively unaffected by the energy fluctuations. Although the desalination process might require more time to be completed when operating under extreme wind speed fluctuations and intermittencies, the quality of the drinking water produced was always within the WHO standards. In conclusion, the findings from this research prove the wind-ED system to be an energetically robust and a reliable off-grid desalination technique suitable for the treatment of brackish groundwater in water stressed remote regions.
29
Mason, Pamela Anne. "The Standing Stock of Organic Matter in a Man-Made Brackish Marsh and its Resource Management Implications". W&M ScholarWorks, 1989. https://scholarworks.wm.edu/etd/1539617607.
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Roque, Jennifer C. "Evaluation of an On-Line Device to Monitor Scale Formation in a Brackish Water Reverse Osmosis Membrane Process". Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5470.
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A modified two-element membrane pressure vessel assembly has been used to monitor process operational changes in a full-scale reverse osmosis (RO) water treatment plant (WTP). This study evaluated the effectiveness of the assembly as an on-line monitoring device intended to detect scale formation conditions when connected to an operating RO process train. This study was implemented to support the requirements of a larger University of Central Florida (UCF) research project ongoing at the city of Sarasota's Public Works and Utilities (City) water treatment facilities located in Sarasota, Florida. During the time-frame of this study, the City was in the process of eliminating their sulfuric acid feed from the pretreatment system of their existing 4.5 million gallon per day (MGD) RO membrane process. The City was motivated to eliminate its dependence on sulfuric acid to reduce operating costs as well as reduce operation health and safety risks associated with the use of the acid as a pretreatment chemical. Because the City was concerned with secondary process impacts associated with acid elimination, additional measures were desired in order to protect the full-scale process. This thesis reports on the design, fabrication and installation of a third-stage two membrane element pressure vessel “canary” sentinel monitoring device (Canary), its effectiveness as an on-line scaling monitor during full-scale acid elimination, and presents the results of the study. The Canary sentinel device was controlled using the normalized specific flux of the two membrane elements fed by a portion of the second stage concentrate of one of the City's full-scale RO process skids. Although the Canary demonstrated the ability to detect changes in an RO process operation, scaling did not occur under the conditions evaluated in this study. An autopsy of one of the Canary elements revealed that no scaling had occurred during the acid elimination process. Therefore, the Canary was found to be useful in its function as a sentinel, even though no scaling was detected by the device after acid elimination at the City's full-scale plant had been accomplished.ID: 031001503; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Adviser: Steven J. Duranceau.; Title from PDF title page (viewed July 26, 2013).; Thesis (M.S.Env.E.)--University of Central Florida, 2012.; Includes bibliographical references (p. 70-73).
M.S.Env.E.
Masters
Civil, Environmental, and Construction Engineering
Engineering and Computer Science
Environmental Engineering
31
Kambanda, Kaliki [Verfasser], e Wolfhard [Akademischer Betreuer] Symader. "Evaluation- of- desalination- techniques- for- treating the- brackish- water- of- Olushandja- subâ€basin- / Kaliki Kambanda ; Betreuer: Wolfhard Symader". Trier : Universität Trier, 2015. http://d-nb.info/1197701036/34.
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Osório, João Vasco de Carvalho. "Mucosal and physiological responses of Atlantic salmon (Salmo salar) in brackish water RAS following peracetic acid-based disinfection". Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2020. http://hdl.handle.net/10400.5/20695.
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Dissertação de Mestrado Integrado em Medicina VeterináriaPeracetic acid (PAA), a strong oxidative disinfectant, is effective against several microorganisms at low concentrations, requires short contact time and degrades rapidly into innocuous residues, thus considered a promising option for routine disinfection in aquaculture production. However, comprehensive knowledge of the impacts of the oxidant PAA on fish health is required for its safe application. This study documented the physiological impacts of periodic PAA exposure in Atlantic salmon (Salmo salar) post-smolts reared in brackish water recirculating aquaculture system. Salmon were exposed to PAA at a concentration of 1 mg/L every 3 days over 6 weeks. Three extensive tissue samplings were conducted (before exposure, 22 and 45 days of periodic PAA exposure). In addition, a stress test was performed before exposure and 45 days post-exposure to assess the effects of periodic exposure during a secondary stress encounter. There was no clear pattern on the changes in plasma stress parameters throughout the exposure trial, except with the glucose level, which significantly decreased over time. Oxidative stress was likely triggered by periodic oxidant exposure, as indicated by the documented significant increase in plasma antioxidants. PAA-induced expression of genes encoding for antioxidants, cytokines, heat shock proteins and mucins demonstrated a tissue-specific pattern: downregulation was observed in the gills and olfactory rosette, upregulation occurred in the skin, and no changes in the liver. Periodic oxidant exposure resulted in histological changes in key mucosal organs (olfactory rosette, skin and gills); pathological alterations were predominant in the gills where cases of epithelial lifting, hypertrophy, hyperplasia and lamellar clubbing were the most commonly identified. Lastly, periodic oxidant exposure did not alter the ability of salmon to mount robust physiological stress responses to a secondary stressor. Collectively, the present study demonstrated that periodic PAA exposure constituted an environmental stressor for which salmon were capable of mounting adaptive responses, both at the systemic and mucosal levels. In addition, periodic PAA exposure promoted the maintenance of stable microbiological water quality and did not affect the biofilter performance. The consequences of this disinfection protocol underscored the potential of PAA as a routine oxidant-based disinfection in salmon RAS production.
RESUMO - O ácido paracético (PAA), um desinfetante com fortes propriedades oxidantes, é eficaz contra diversos microrganismos a baixas concentrações, requer um curto tempo de contacto e degrada-se rapidamente em resíduos inócuos, sendo, portanto, considerado uma alternativa promissora para a desinfeção de rotina em aquacultura. No entanto, é necessário um extenso conhecimento relativo aos impactos do PAA na saúde dos peixes para garantir a sua utilização segura. Este estudo documentou as consequências fisiológicas da exposição periódica ao PAA em Salmão do Atlântico (Salmo salar) na fase “post-smolt”, produzido num sistema de recirculação em aquacultura (RAS) de água salobra. Os peixes foram expostos ao PAA a uma concentração de 1 mg/L a cada 3 dias durante 6 semanas. Foram realizadas três recolhas extensivas de tecidos (antes da exposição, e aos dias 22 e 45 de exposição periódica). Além disso, foi realizado um desafio de stress antes do início de exposição e no dia 45 de exposição para avaliar os efeitos da exposição periódica na resposta a um estímulo secundário de stress. Durante o estudo não foi observado nenhum padrão óbvio na evolução dos parâmetros plasmáticos de stress, excetuando os níveis de glucose, que desceram significativamente ao longo do tempo. O stress oxidativo foi induzido provavelmente pela exposição periódica ao oxidante, tal como indicado pelo aumento nos níveis de antioxidantes plasmáticos. A expressão dos genes que codificam antioxidantes, citoquinas, proteínas de choque térmico e mucinas revelou que existe um padrão tecidular específico em resposta ao PAA: foi registado um padrão de inibição nas brânquias e na roseta olfatória, um padrão de indução na pele, enquanto no fígado não foram registadas alterações. A exposição ao PAA provocou alterações histológicas nas brânquias, pele e roseta olfatória, sendo as alterações predominantemente observadas nas brânquias, onde as alterações mais comuns foram casos de edema epitelial, hipertrofia, hiperplasia e “lamelar clubbing”. A exposição periódica ao PAA não afetou a capacidade do salmão para estabelecer uma resposta fisiológica eficiente na presença de um estímulo indutor de stress. De forma geral, este estudo demonstrou que a exposição periódica ao PAA constituiu um estímulo stressante para o qual os peixes foram capazes de apresentar respostas adaptativas, tanto a nível sistémico como nas mucosas. Além disso, a exposição ao PAA promoveu a manutenção da qualidade microbiológica da água e não afetou a performance do biofiltro. As respostas observadas neste protocolo de desinfeção destacam o potencial do PAA como um desinfetante de rotina na produção de salmão em RAS.
N/A
33
Karlsson, Jenny. "Hazard Identification of Anti-fouling Paints and Contaminated Sediments by the Use of Biological Tests in Brackish Water /". Stockholm : Department of Applied Environmental Science (ITM), Stockholm Univeristy, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-29610.
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Diss. (sammanfattning) Stockholm : Stockholms universitet, 2009.At the time of the doctoral defense, the following papers were unpublished and had a status as follows:Paper 2: submitted; Paper 3: submitted; Paper 4: manuscript. Härtill 5 uppsatser.
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Bahman, Abdul-Redha Majeed. "Comparisons of date-palm leaves with barley straw and brackish water with fresh water for dairy cows given a high concentrate diet in Kuwait". Thesis, University of Aberdeen, 1991. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU602309.
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The main objectives of the work described in this thesis were to determine the technical feasibility of utilising date palm leaves as a potential source of roughage, and to study the effects of providing brackish water as a source of drinking water for dairy cows. Additionally, to investigate the effect of feeding a high concentrate diet on the performance of Friesian cows. Four experiments were performed during the course of three years (November 1988 - June 1991). Three experiments were carried out in Kuwait and one in the North of Scotland. Experiment 1 was designed to compare the effects of feeding locally produced date palm leaves (DPL) with imported barley straw (S) as roughages to milking cows given a high concentrate diet. Fifty-six cows were used from the fifth week of lactation for 12 weeks. Experiment 2 studied the performance of thirty eight non-lactating pregnant cows for about 15 weeks, with the same objective as experiment 1. Each of these experiments included a small trial for more detailed studies. In experiment 3 eight milking cows in the sixth week of lactation were studied for over six months to compare the effects of drinking brackish water (BW) with fresh water (FW) on the performance of the cows fed on a high concentrate diet in addition to DPL and freshly cut alfalfa. Experiment 4 was conducted in the North of Scotland to investigate the effects of feeding a high concentrate diet, similar to that of Kuwait, on the productivity and the ruminal fermentation of high yielding cows. The general conclusions drawn from these four experiments are: 1. Despite the low qulaity of DPL, it might be a suitable alternative to straw as a source of roughage for dairy cows in Kuwait. 2. Brackish water is a palatable and harmless source of drinking water, and its mineral content may be beneficial in contributing to the dairy cows dietary requirements. 3. Feeding a high level of concentrate in diets based on grass silage increases milk yield and favours body gain at the expense of milk fat content. 4. There is a need for better utilization and processing of local agricultural by-products in Kuwait for the feeding of ruminants. 5. Further research is required to investigate the performance of dairy cows under different environments, especially hot-arid conditions.
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Al, Anqah Laila. "Trace element contaminants in the Kuwait water production system". Thesis, Brunel University, 1996. http://bura.brunel.ac.uk/handle/2438/5012.
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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.
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Felix, Joseph David. "Methanol, formaldehyde, and acetaldehyde in rain ; Development of a method to determine [delta] ¹⁵N-NO₂⁻ and NO₃⁻ in fresh and brackish waters". View electronic thesis, 2008. http://dl.uncw.edu/etd/2008-3/felixj/josephfelix.pdf.
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Zhao, Yu. "Reverse osmosis desalination in a mini renewable energy power supply system". Thesis, Curtin University, 2006. http://hdl.handle.net/20.500.11937/2099.
Texto completo da fonteResumo:
The design, construction and testing of a reverse-osmosis (PV-RO) desalination system for fresh water shortage area is presented. The system operates from salt water or brackish water and can be embedded in a renewable energy power supply system, since many fresh shortage areas are remote and isolated. Special attention is given to the energy efficiency of small-scale reverse osmosis desalination systems. Limitations of conventional control strategy using toggle control are presented. Based on this, an objective of creating a small-scale reverse osmosis desalination system was set out. Initially, the background information is presented. This includes the natural resources crisis and main desalination technologies and the viability of the integration with renewable energy source. A reverse osmosis (RO) desalination system was assembled and set up at the Curtin University of Technology, Perth, Western Australia Supervisor Control And Data Acquisition (SCADA) system was built using a Human Machine Interface software and a programmable logic controller (PLC). Instrumentation that included signal conditioners was made in analysis of the system characteristics. Initial testing of the system was conducted after the system design and configuration was accomplished. Testing results were used as a guideline for the development of the whole system.Modelling and simulation of the system components in MATLABSimulink is presented, together with a discussion of the control systems modelling and design procedure, in which the aim was to improve the efficiency of the reverse osmosis system. Simulations show the designed reverse osmosis system with Proportional Integral and Derivative (PID) controller has better performance than other controllers. This consequently leads to a lower overall cost of the water, as well as reducing full maintenance cost of the electric drives in the reverse osmosis unit. Additionally, the configuration of the remote control system through General Package Radio System (GPRS) network is depicted. After the PID control algorithm was programmed into the Programmable Logic Controller (PLC), system experiments were carried out in short durations and long durations. System performance was monitored and experimental results prove that the new control strategy applied increase the water productivity and is able to improve the system efficiency up to 35%. Based on the data obtained from the simulations and experiments, Mundoo Island was chosen to be the location for a case study. The electric load profile of the island was derived from the Island Development Committee in Mundoo.A water demand profile was created and modelled in Matlab to be the input of the reverse osmosis system. The electric load of the reverse osmosis system was generated from Matlab simulation. This result was entered in Hybrid Optimisation Model for Electric Renewables (HOMER) simulator. Having the designed RO unit as one of the electric loads, the entire remote area power supply (RAPS) system was tested in simulations which shows the energy cost is AUS$0.174 per kWh, lower than the Island Development Committee budget estimation of AUS$0.25 per kWh. The cost of the water treatment is very promising at AUS$0.77 per m3.
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Salas, Massó Núria. "Epidemiology of arcobacter-related spp. In shellfish exposed to marine and brackish water with different levels of fecal pollution". Doctoral thesis, Universitat Rovira i Virgili, 2019. http://hdl.handle.net/10803/668373.
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El gènere Arcobacter, que ha estat recentment dividit en 7 nous gèneres, comprèn espècies zoonòtiques i patògenes. Aquests gèneres han estat detectats, amb un alt percentatge de positivitat en marisc i juntament amb el fet que aquests aliments són consumits poc cuinats, suposen un risc per al consumidor. En aquesta tesi, s'ha estudiat la relació entre aquests bacteris i bivalves exposats a aigües amb diferents nivells de contaminació fecal. El desenvolupament d'una nova metodologia, que consisteix en el suplement del brou Arcobacter-CAT amb 2.5% NaCl i el seu posterior cultiu en agar marí, ha millorat l'aïllament d'espècies relacionades amb Arcobacter d'ambients salobres i marins. Una correlació positiva entre els nivells de Escherichia coli i Arcobacter va ser observada en bivalves i la seva aigua circumdant. No obstant això, quan els bivalves són cultivats en aigua amb temperatures superiors a 26.2ºC, E. coli no prediu la presència d'aquests patògens. L'avaluació de la distribució de Arcobacter en els teixits de musclos i ostrons, va mostrar que el líquid intervalval és el compartiment amb major prevalença de Arcobacter. La depuració de E coli, A. butzleri i M. molluscorum en musclo i ostró sota diferents condicions de càrrega bacteriana i en dues estacions diferents (estiu i hivern) va ser analitzada. Es va observar que aquest procés no elimina del tot Arcobacter dels bivalves, i que depèn de la temperatura. També es va desenvolupar una v-qPCR per a la detecció de cèl·lules viables de Arcobacter spp. en diferents bivalves. Aquest mètode va aconseguir una inhibició de l'amplificació de l'ADN procedent de cèl·lules mortes en el 85% de les espècies de Arcobacter examinades. Com a resultat de tots aquests experiments, juntament amb l'ús en paral·lel de la metodologia enriquida i no enriquida amb NaCl, s'han aïllat i descrit set noves espècies pertanyents a quatre nous gèneres.El género Arcobacter, que ha sido recientemente dividió en 7 nuevos géneros, comprende especies zoonoticas y patógenas. Estos géneros han sido detectados, con un alto porcentaje de positividad en marisco y junto con el hecho de que estos alimentos son consumidos poco cocinados, suponen un riesgo para el consumidor. En esta tesis, se ha estudiado la relación entre estas bacterias y bivalvos expuestos a aguas con diferentes niveles de contaminación fecal. El desarrollo de una nueva metodología, consistente en el suplemento del caldo Arcobacter-CAT con 2.5%NaCl y su posterior cultivo en agar marino, ha mejorado el aislamiento de especies relacionadas con Arcobacter de ambientes salobres y marinos. Una correlación positiva entre los niveles de Escherichia coli y Arcobacter fue observada en bivalvos y su agua circundante. Sin embargo, cuando los bivalvos son cultivados en agua con temperaturas superiores a 26.2ºC, E. coli no predice la presencia de estos patógenos. La evaluación de la distribución de Arcobacter en los tejidos de mejillones y ostrones, mostró que el líquido intervalval es el compartimento con mayor prevalencia de Arcobacter. La depuración de E. coli, A. butzleri y M. molluscorum en mejillón y ostrón bajo distintas condiciones de carga bacteriana y en dos estaciones distintas (verano e invierno) fue analizada. Se observó que este proceso no elimina del todo Arcobacter de los bivalvos, y que es dependiente de la temperatura. También se desarrolló una v-qPCR para la detección de células viables de Arcobacter spp. en diferentes bivalvos. Este método consiguió una inhibición de la amplificación del ADN procedente de células muertas en el 85% de las especies de Arcobacter examinadas. Como resultado de todos estos experimentos, junto con el uso en paralelo la metodología enriquecida y no enriquecida con NaCl, se han aislado y descrito siete nuevas especies pertenecientes a cuatro nuevos géneros.
The genus Arcobacter, which recently has been divided into 7 new genera, comprises species that have been considered zoonotic agents and emergent pathogens. Arcobacter-related species have been recovered with a high positivity from seafood, posing a risk for the consumer as they are consumed raw or slightly cooked. In this thesis, the relationship between these bacteria and shellfish exposed to water with different levels of fecal pollution has been studied. A new approach, for improving the recovery of Arcobacter-related genera from marine and brackish environments was developed and consisted on the supplementation of Arcobacter-CAT broth with 2.5% NaCl and posterior culture in marine agar. The correlation between the levels of Escherichia coli and Arcobacter was also examined in shellfish and their surrounding water, showing positive results. However, when shellfish were harvested from water with a temperature above 26.2ºC, E. coli would fail to predict the presence of these pathogens. The distribution of Arcobacter-related genera within the tissues of mussels and oysters showed that the intervalval liquid was the compartment with higher prevalence of Arcobacter. Depuration of E. coli, A. butzleri and M. molluscorum in mussels and oysters under different bacterial loads and in two seasons (summer and winter) was analyzed. The efficacy of the conventional depuration process may not fully eliminate Arcobacter from shellfish and, probably, it is a temperature dependent process. A viable qPCR method for the detection of viable Arcobacter spp. cells in different shellfish matrixes was developed with a satisfactory inhibition of DNA amplification from dead cells in 85% of the Arcobacter species tested. As results of all these experiments, together with the use in parallel of the NaCl.enriched and non-enriched approaches, the isolation and description of seven new species belonging to four new different genera was performed.
39
Hubbard, Stephen Michial. "Sedimentology and ichnology of brackish water deposits in the Bluesky Formation and Ostracode Zone, Peace River Oil Sands, Alberta". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0017/MQ47042.pdf.
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Kullmann, Björn [Verfasser], e Ralf [Akademischer Betreuer] Thiel. "Growth and condition of stocked glass and farmed eels in a brackish water system / Björn Kullmann ; Betreuer: Ralf Thiel". Hamburg : Staats- und Universitätsbibliothek Hamburg, 2018. http://d-nb.info/1169358314/34.
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Banasiak, Laura Joan. "Removal of inorganic and trace organic contaminants by electrodialysis". Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/3998.
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With the continual concern over the presence of naturally occurring and anthropogenic inorganic and trace organic contaminants in the aquatic environment there is a growing need for the implementation of innovative treatment processes for the elimination of these contaminants from natural waters and wastewater effluents. While conventional treatment methods are ineffective in the removal of emerging contaminants such as steroidal hormones and pesticides, membrane technology, including electrodialysis (ED), has been highlighted as a potential treatment option. However, the clear lack of fundamental understanding of the behaviour of contaminants in ED is a current limitation for its extensive utilisation and is a critical issue that needs to be addressed. ED processing potentialities have not been fully exploited and more research is needed to account for all the key parameters such as contaminant physicochemical properties, solution chemistry and the presence of organic matter. The purpose of this study was to elucidate the mechanisms of inorganic and trace organic contaminant removal by ED. The inorganic contaminants fluoride, nitrate and boron were selected due to their ubiquitous nature in the environment and public health concerns resulting from longterm exposure. The hydrated radius and strength of hydration shells played a significant role in ionic transport, whereby nitrate with a smaller hydrated radius was removed more effectively (94.1 %) than fluoride (68.3 %) with a larger hydrated radius. While fluoride and nitrate removal was pH independent, the pH dependent speciation of boron enhanced its removal with increasing pH. Territorial binding and/or complexation of the inorganics with organic matter enhanced removal. The removal of a range of trace inorganics (e.g. arsenic, calcium, magnesium, uranium) from a brackish groundwater from a remote Australian community was investigated. Undissociated inorganics were not transported through the membranes, whereas dissociated inorganics were due to electrostatic attraction. At acidic-neutral conditions ionic transport was the dominant removal mechanism. At neutral to alkaline conditions insoluble carbonate species precipitated and deposited as a membrane scaling layer (60 μm). This has serious implications for the long-term practical applicability of ED to treat real waters as scaling increased ED stack resistance (pH 3: 27.5 4, pH 11: 50 4) and decreased total dissolved solids removal (pH 3: 99 %, pH 11: 89.5 %). While the treatment of trace organics by other membrane processes has been widely studied, their fate in ED and interaction with ED membranes is relatively unknown. Trace contaminant-membrane interaction studies were undertaken to quantify the partitioning of trace organics; namely steroidal hormones and the pesticide endosulfan, to ED membranes by measuring membrane-water partition coefficients (log KM). The extremely high sorption capacity of the membranes was attributed to hydrogen bonding between the trace organic and membrane functional groups. Hormone sorption during ED was influenced by solution pH and organic matter. In the case of estrone, membrane sorption decreased at pH 11 (487 μg/cm3) compared to pH 7 (591 μg/cm3) due to dissociation and membrane electrostatic repulsion .At pH 11, repulsion between dissociated estrone and HA coupled with membrane electrostatic attraction resulted in increased sorption. The findings from this study highlight that the transport of trace contaminants will depend largely on the characteristics of the membranes used in the ED process as well as the physicochemical characteristics of the contaminants, their interaction with the ED membranes and the presence of other inorganic and/or organic compounds. The knowledge gained has direct applications to current problems and uncertainties in water and wastewater treatment with regards to the fate and transport of contaminants.
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Stevenson, James Ronald. "Sustainability of brackish-water pond aquaculture systems : a farm-level analysis of economic, social and ecological dimensions in the Philippines". Thesis, University of Reading, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427839.
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Zhao, Yu. "Reverse osmosis desalination in a mini renewable energy power supply system". Curtin University of Technology, Dept. of Electrical and Computer Engineering, 2006. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=18552.
Texto completo da fonteResumo:
The design, construction and testing of a reverse-osmosis (PV-RO) desalination system for fresh water shortage area is presented. The system operates from salt water or brackish water and can be embedded in a renewable energy power supply system, since many fresh shortage areas are remote and isolated. Special attention is given to the energy efficiency of small-scale reverse osmosis desalination systems. Limitations of conventional control strategy using toggle control are presented. Based on this, an objective of creating a small-scale reverse osmosis desalination system was set out. Initially, the background information is presented. This includes the natural resources crisis and main desalination technologies and the viability of the integration with renewable energy source. A reverse osmosis (RO) desalination system was assembled and set up at the Curtin University of Technology, Perth, Western Australia Supervisor Control And Data Acquisition (SCADA) system was built using a Human Machine Interface software and a programmable logic controller (PLC). Instrumentation that included signal conditioners was made in analysis of the system characteristics. Initial testing of the system was conducted after the system design and configuration was accomplished. Testing results were used as a guideline for the development of the whole system.Modelling and simulation of the system components in MATLABSimulink is presented, together with a discussion of the control systems modelling and design procedure, in which the aim was to improve the efficiency of the reverse osmosis system. Simulations show the designed reverse osmosis system with Proportional Integral and Derivative (PID) controller has better performance than other controllers. This consequently leads to a lower overall cost of the water, as well as reducing full maintenance cost of the electric drives in the reverse osmosis unit. Additionally, the configuration of the remote control system through General Package Radio System (GPRS) network is depicted. After the PID control algorithm was programmed into the Programmable Logic Controller (PLC), system experiments were carried out in short durations and long durations. System performance was monitored and experimental results prove that the new control strategy applied increase the water productivity and is able to improve the system efficiency up to 35%. Based on the data obtained from the simulations and experiments, Mundoo Island was chosen to be the location for a case study. The electric load profile of the island was derived from the Island Development Committee in Mundoo.
A water demand profile was created and modelled in Matlab to be the input of the reverse osmosis system. The electric load of the reverse osmosis system was generated from Matlab simulation. This result was entered in Hybrid Optimisation Model for Electric Renewables (HOMER) simulator. Having the designed RO unit as one of the electric loads, the entire remote area power supply (RAPS) system was tested in simulations which shows the energy cost is AUS$0.174 per kWh, lower than the Island Development Committee budget estimation of AUS$0.25 per kWh. The cost of the water treatment is very promising at AUS$0.77 per m3.
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Menezes, Joilma da Silva. "Desenvolvimento de dispositivo caseiro para dessalinização de água salobra para dessedentação humana". Programa de Pós-Graduação em Química da UFBA, 2009. http://www.repositorio.ufba.br/ri/handle/ri/9998.
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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
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Lindkvist, Jonas. "Social, Economical and Technical Evaluation of a reverse osmosis drinking water plant in the Stockholm Archipelago". Thesis, KTH, Industriell ekologi, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-32777.
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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
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Ståhlberg, Carina. "Mineralisation rates of natural organic matter in surface sediments affected by physical forces : a study of fresh- and brackish-water sediments subjected to changed redox conditions, resuspension, and advective pore water flow /". Linköping : Department of Water and Environmental Studies, [The Tema Institute], Linköping University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8332.
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Rodrigues, Ana Carolina Martins. ""Balanço de massa de um sistema de ultrafiltração e osmose reversa para desssalinização de água salobra"". Universidade Estadual de Ponta Grossa, 2018. http://tede2.uepg.br/jspui/handle/prefix/2551.
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Fundação Araucária de Apoio ao Desenvolvimento Científico e Tecnológico do Paraná
A má distribuição de água doce no mundo, o crescimento populacional acentuado, as mudanças climáticas e as consequências das ações antropológicas traz a necessidade da busca de fontes alternativas para suprir a demanda de água aos seres humanos, animais e plantas. A abundância de água salgada ou salobra é muitas vezes, a única fonte de água disponível para sobrevivência de algumas comunidades no planeta, isso tem impulsionado o uso de técnicas de dessalinização. Com o objetivo de estudar alternativas para adaptações climáticas, antecipar tendências e problemas hídricos futuros foi implantado um sistema de dessalinização de água salobra, em escala piloto, nas dependências da Estação de Tratamento de Água (ETA) da Sanepar, em Praia de Leste, no município de Pontal do Paraná no litoral do estado. O sistema piloto foi provido de ultrafiltração (UF) como pré-tratamento seguido de abrandamento e da dessalinização por osmose reversa (OR). Com capacidade para produzir 1 m3.h-1 de água tratada. A água salobra foi padronizada nas concentrações de 1000 ± 50 mg.L-1 e 1500 ± 20 mg.L-1 de sólidos dissolvidos totais (SDT), por meio da mistura da água do mar e da água bruta do Rio das Pombas, manancial que abastece o balneário. Avaliou-se o sistema global a partir de dados de produção e consumo de água, balanço de massa e das taxas de recuperação para configurações diferentes do sistema de OR. Para isso, foram realizados quatro experimentos, variando a configuração de abertura do registro do concentrado da OR: o primeiro com abertura de 72,71% de concentrado (A); o segundo 59,20 % (B); o terceiro 39,70% (C), estes com 1500 ± 20 mg.L-1 de SDT; o quarto experimento foi realizado para 1000 ± 50 mg.L-1 de SDT com abertura de 32,90% de concentrado (D). Aproximadamente 15% do volume de alimentação era utilizado na limpeza hidráulica das membranas da UF e da OR. Quanto maiores as vazões do concentrado da OR, maior a vazão de alimentação, e consequentemente, menor a taxa de recuperação e pressão osmótica. A maior taxa de recuperação obtida foi de 69,13% para o experimento D, sendo considerada a configuração mais otimizada.
With the unequal distribution of fresh water in the world, strong population growth, climate change and the consequences of anthropological actions it is necessary to look for alternative sources to supply the water demand for human beings, animals and plants. Salt water or brackish water has been the only source of water available for survival in some communities on the planet. This issue has driven the use of desalination techniques. With the objective of studying alternatives for climate adaptation, anticipating of trends and problems and water problems, a brackish water desalination system in pilot scale was implemented on the premises of the Water Treatment Plant Station, in Praia de Leste, in the Pontal do Paraná City, coast of the State. The pilot system was provided with ultrafiltration (UF) as a pretreatment followed by softening and reverse osmosis (RO), with the capacity to produce 1m3.h-1 of permeate. Brackish water was produced at concentrations of 1,000 ± 50 mg.L-1 and 1,500 ± 20 mg.L-1 of total dissolved solids (TDS), by mixing sea water and fresh water from the Pombas River, which supplies the town. The global system was evaluated from production and water consumption data, mass balance and recovery rates for different configurations of the reverse osmosis system. For this, four experiments were performed, varying the configuration of the valve which controls the flow of the brine: the first one with 72.71% (A); the second with 59.20%(B); the third with 39.70% (C), these with 1,500 ± 20 mg.L-1 of TDS; the fourth experiment was also performed for 1,000 ± 50 mg.L-1 of TDS with 32.90% of the brine (D). About 15% of volume of water produced was used in the hydraulic cleaning of the UF and RO membranes. When the flow rates of the concentrate were higher, the feed rates were also higher and consequently, the recovery rates and osmotic pressure were lower. The highest recovery rate was 69.13% for the experiment D, being considered the most optimized configuration.
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Bovaroti, Tatiane. "Avaliação de um sistema de dessalinização de água salobra em escala piloto". Universidade Estadual de Ponta Grossa, 2018. http://tede2.uepg.br/jspui/handle/prefix/2578.
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Preocupados com a intrusão de água do mar, escassez e má qualidade das reservas de água doce no mundo, diversos países têm estudado e proposto sistemas de alta tecnologia que sejam viáveis para a dessalinização de água salobra ou salina. Este trabalho teve como objetivo principal avaliar a eficiência de um sistema de ultrafiltração (UF) como pré-tratamento, seguido de abrandamento e osmose reversa (OR) para a dessalinização de água salobra em escala piloto, instalado no balneário de Praia de Leste, litoral do estado do Paraná. Para a obtenção da água salobra foi realizada a mistura da água do rio das Pombas com a água do mar até a concentração de 1500 (± 100) mg. L-1 de sólidos dissolvidos totais (SDT). O sistema foi projetado para a produção de 1 m3.h-1 de água doce (permeado da OR) e operou por aproximadamente 3h por dia durante vinte dias não consecutivos. Analisaram-se amostras de nove pontos de coleta durante a primeira (A), segunda (B) e terceira (C) hora de operação. Para a avaliação da qualidade da água os parâmetros analisados foram: SDT, condutividade elétrica, pH, temperatura, cor aparente, turbidez, alcalinidade total, dureza total, cálcio, cloreto, sulfato, coliformes totais e E.coli. Para avaliação da eficiência do sistema, calculou-se a taxa de recuperação e o fluxo de filtração, bem como a leitura de outros parâmetros operacionais como a pressão osmótica. O sistema de UF apresentou remoção média de 95,1% de turbidez e de 98,6% de cor aparente na água salobra. Constatou-se ausência de coliformes totais e E.coli no permeado. Houve variação quanto à remoção de dureza total e cálcio pelo abrandador devido ao tempo de regeneração do sistema. O sistema de OR obteve remoção média de 99,4% de SDT e a maior taxa de recuperação global (UF e OR) foi de 57,4%.
Concerned about the intrusion of sea water, scarcity and poor quality of freshwater reserves in the world, several countries have studied and proposed high technology systems that are feasible for the desalination of brackish or saline water. The main objective of this work was to evaluate the efficiency of an ultrafiltration (UF) system as a pretreatment, followed by slowing and reverse osmosis (RO) for pilot scale saline water desalination, installed in Praia de Leste – coast of the state of Paraná. To obtain the brackish water, the water of the Pombas River was mixed with sea water up to the concentration of 1500 (± 100) mg. L-1 total dissolved solids (TDS). The system was designed to produce 1 m3.h-1 of freshwater (permeate from the RO) and was operated by approximately 3 hours per day during twenty non-consecutive days. Samples from nine collection points were analyzed during the first (A), second (B) and third (C) hours of operation. In order to evaluate the water quality, the parameters evaluated were: TDS, electric conductivity, pH, temperature, apparent color, turbidity, total alkalinity, total hardness, calcium, chloride, sulfate, total coliforms and E.coli. To evaluate the efficiency of the system, the recovery rate and the filtration flow were calculated, as well as the reading of other operational parameters such as osmotic pressure. It was found absence of total coliforms and E. coli in the permeate. There was variation regarding to the removal of total hardness and calcium by the softener due to the regeneration time of the system. The RO system obtained an average of 99.4% of the TDS removal and the highest overall (UF and RO) recovery rate was 57.4%.
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Mexicano, Vargas Maria de Lourdes. "Remote Sensing Methods To Classify a Desert Wetland". Diss., The University of Arizona, 2012. http://hdl.handle.net/10150/232457.
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The Cienega de Santa Clara is a 5600 ha, anthropogenic wetland in the delta of the Colorado River in Mexico. It is the inadvertent creation of the disposal of brackish agricultural waste water from the U.S. into the intertidal zone of the river delta in Mexico, but has become an internationally important wetland for resident and migratory water birds. The marsh is dominated by Typha domengensis with Phragmites australis as a sub-dominant species in shallower marsh areas. The most important factor controlling vegetation density was fire. The second significant (P<0.01) factor controlling NDVI was flow rate of agricultural drain water from the U.S. into the marsh. Reduced summer flows in 2001 due to canal repairs, and in 2010 during the YDP test run, produced the two lowest NDVI values of the time series from 2000 to 2011 (P<0.05). Salinity is a further determinant of vegetation dynamics as determined by greenhouse experiments, but was nearly constant over the period 2000 to 2011, so it was not a significant variable in regression analyses. Evapotranspiration (ET) and other water balance components were measured in Cienega de Santa Clara; we used a remote sensing algorithm to estimate ET from meteorological data and Enhanced Vegetation Index values from the Moderate Resolution Imaging Spectrometer (MODIS) sensors on the Terra satellite. We used Landsat NDVI imagery from 1978-2011 to determine the area and intensity of vegetation and to estimate evapotranspiration (ET) to construct a water balance. Remote sensing data was supplemented with hydrological data, site surveys and literature citations. The vegetated area increased from 1978 to 1995 and has been constant at about 4200 ha since then. The dominant vegetation type is Typha domingensis (southern cattail), and peak summer NDVI since 1995 has been stable at 0.379 (SD = 0.016), about half of NDVI(max). About 30% of the inflow water is consumed in ET, with the remainder exiting the Cienega as outflow water, mainly during winter months when T. domingensis is dormant.
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Shawahna, Ayman A. M. [Verfasser], Martin [Akademischer Betreuer] Sauter, Bernd [Gutachter] Rusteberg e Bernd [Gutachter] Rusteberg. "Water management strategies towards sustainable agricultural development, taking Managed Aquifer Recharge (MAR) and brackish water utilization into Account: Case Study: Auja, LJV, Palestine. / Ayman A.M Shawahna ; Gutachter: Bernd Rusteberg, Bernd Rusteberg ; Betreuer: Martin Sauter". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/1188464833/34.
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