• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 160
  • 44
  • 16
  • 6
  • 5
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 2
  • 1
  • Tagged with
  • 297
  • 297
  • 130
  • 80
  • 79
  • 56
  • 50
  • 49
  • 48
  • 37
  • 31
  • 30
  • 29
  • 27
  • 27
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Flexible design and operation of multi-stage reverse osmosis desalination process for producing different grades of water with maintenance and cleaning opportunity

Al-Obaidi, Mudhar A.A.R., Rasn, K.H., Aladhwani, S.H., Kadhom, M., Mujtaba, Iqbal 20 April 2022 (has links)
Yes / The use of Reverse Osmosis (RO) process in seawater desalination to provide high-quality drinking water is progressively increased compared to thermal technologies. In this paper, multistage spiral wound RO desalination process is considered. Each stage consists of several pressure vessels (PVs) organised in parallel with membrane modules in each PV being organised in series. This allows disconnecting a set of PVs and membrane modules depending on the requirement of cleaning and maintenance. While this flexibility offers the opportunity of generating several RO configurations, we presented only four such configurations of the RO system and analysed them via simulation and optimisation. Production of different grades of water catering different needs of a city is also considered for each of these configurations. The optimisation has resulted in the optimal operating conditions, which maximises the water productivity and minimises the specific energy consumption of the proposed configurations for a given water grade in terms of salinity. For instance, the results indicate that the proposed RO networks can produce drinking water of 500 ppm salinity with a minimum specific energy consumption of 3.755 kWh/m3. The strategy offers the production of different grades of water without plant shutdown while maintaining the membrane modules throughout the year.
82

Optimal design and operation of reverse osmosis desalination process with membrane fouling

Sassi, Kamal M., Mujtaba, Iqbal January 2011 (has links)
No description available.
83

Operation and modelling of RO desalination process in batch mode

Barello, M., Manca, D., Patel, Rajnikant, Mujtaba, Iqbal 28 May 2015 (has links)
Yes / The performance of a batch reverse osmosis (RO) desalination process in terms of permeate quantity and salinity as a function of feed pressure and feed salinity is evaluated by using laboratory experiments and process modelling. Special attention is paid to the water and salt permeability constants (Kw, Ks) which affect the permeate and salt flux across the membrane. Kw and Ks are found to be strongly pressure-dependent for the batch system which is in-line with earlier observations for continuous RO systems. However, the most important findings of this work are the dependence of Kw and Ks on feed salinity, something that have never been observed or reported in the literature. In order to better qualify these observations, further experiments with the batch system are conducted with a constant feed salinity so that the operating condition resembles that of a continuous RO process.
84

Removal of organic contaminants from groundwater by reverse osmosis

Robinson, Michael A. 14 March 2009 (has links)
The performance of a poly(ether/urea) membrane has been evaluated in a full scale reverse osmosis system. A series of experiments were conducted with six aromatic compounds - anthracene, pyrene, fluorene, 2-chlorobiphenyl, 2,4,6 trichlorophenol, and pentachlorophenol- and four volatile compounds - trichloromethane, bromodichloromethane, dibromochloromethane, and trichloroethene - as single and multi-solute contaminants. The objectives of the experiments were to determine if poly(ether/urea) membranes could produce a permeate that met maximum contaminant levels (MCL) set by the Safe Drinking Water Act (SDWA) and to correlate membrane performance with physical/chemical properties of the solute contaminants. Aromatic contaminants were removed to concentrations below the current MCLs. However, volatile contaminants were not sufficiently rejected by the membrane to meet either the MCL for total trihalomethanes or trichloroethene. Sorption onto the poly(ether/urea) was found to occur for several of the aromatic compounds tested in this research. This prevented developing any relationship between membrane performance and physical/chemical properties of the solute. / Master of Science
85

Thermodynamic Limitations and Exergy Analysis of Brackish Water Reverse Osmosis Desalination Process

Alsarayreh, Alanood A., Al-Obaidi, Mudhar A.A.R., Ruiz-Garcia, A., Patel, Rajnikant, Mujtaba, Iqbal M. 28 March 2022 (has links)
Yes / The reverse osmosis (RO) process is one of the most popular membrane technologies for the generation of freshwater from seawater and brackish water resources. An industrial scale RO desalination consumes a considerable amount of energy due to the exergy destruction in several units of the process. To mitigate these limitations, several colleagues focused on delivering feasible options to resolve these issues. Most importantly, the intention was to specify the most units responsible for dissipating energy. However, in the literature, no research has been done on the analysis of exergy losses and thermodynamic limitations of the RO system of the Arab Potash Company (APC). Specifically, the RO system of the APC is designed as a medium-sized, multistage, multi pass spiral wound brackish water RO desalination plant with a capacity of 1200 m3/day. Therefore, this paper intends to fill this gap and critically investigate the distribution of exergy destruction by incorporating both physical and chemical exergies of several units and compartments of the RO system. To carry out this study, a sub-model of exergy analysis was collected from the open literature and embedded into the original RO model developed by the authors of this study. The simulation results explored the most sections that cause the highest energy destruction. Specifically, it is confirmed that the major exergy destruction happens in the product stream with 95.8% of the total exergy input. However, the lowest exergy destruction happens in the mixing location of permeate of the first pass of RO desalination system with 62.28% of the total exergy input.
86

Modeling and analysis of hybrid solar water desalination system for different scenarios in Indonesia

Fairuz, A., Umam, M.F., Hasanuzzaman, M., Rahim, N.A., Mutaba, Iqbal M. 13 July 2023 (has links)
Yes / Clean water demand has significantly increased due to the rise in the global population. However, most water on the Earth has high saline content that cannot be consumed directly; only about one over forty of the total water source is freshwater. Desalinated water is one of the potential solutions to meet the growing demand for freshwater, which is highly energy intensive. This paper analyses the energy, economic and environmental performance of a 5 m3/day PV (photovoltaic) powered reverse osmosis (RO) desalination system. Three scenarios of PV-RO with and without battery storage and diesel generator hybrid systems have been analyzed and investigated for the annual estimate load, net present value, and payback period of the water and electricity production costs. Also, the CO2 avoidance over the lifetime operation of all scearios is evaluated. This study shows that the PV-RO system without battery with 6.3 kW PV panels installed and with a 2-days water storage tank system is the most profitable economically f. For this scenario, the Levelized Cost of Electricity (LCOE), Levelized Cost of Water (LCOW), and Payback Period (PBP) are found to be $0.154/kWh, $0.627/m3, and five years, respectively. In addition, for this scenario, the CO2 emissions avoidance was the maximum (111,690 kg.CO2eq per year) compared to other scenarios.
87

Avsaltningsanläggning för dricksvatten : En undersökning av förutsättningarna att säkra färskvattentillgången i Mönsterås kommun / Desalination plant for drinking water

Larsson, Olof January 2023 (has links)
Detta arbete utreder möjligheten att säkra vattentillgången i Mönsterås kommun med hjälp av en avsaltningsanläggning för bräckvatten från östersjön. Det är högst troligt ett sådant vattenverk skulle kunna uppföras i kommunen och dessutom ge ett vatten med lägre halter av oönskade ämnen än vatten renat med konventionella metoder från yt- och grundvatten till en marginellt högre kostnad. I arbetet redovisas kortfattat principen för avsaltning med RO (Reverse osmosis).  Uppbyggnaden av två vattenverk som använder den tekniken och likt Mönsterås ligger i Kalmarsund beskrivs. Med information från sjökort och kartor har troliga råvattentillgångar i kommunen identifierats och utifrån dessa grundar sig förslagen för placering. Med hjälp från ett flertal kontakter i branschen har en enklare projektering gjorts för ett vattenverk med kapacitet på 3000 kubikmeter dricksvatten per dygn. I resultatet redovisas några förslag på placering av ett vattenverk. / This work investigates the possibility of securing the water supply in Mönsterås municipality with the help of a desalination plant for brackish water from the Baltic Sea. It is highly likely that such a waterworks could be built in the municipality and also provide water with lower levels of unwanted substances than water purified by conventional methods from surface and groundwater at a marginally higher cost. In the work, the principle of desalination with RO (Reverse osmosis) is briefly presented.  The construction of two waterworks that use this technology and, like Mönsterås, is located in Kalmarsund is described.  With information from nautical charts and maps, probable raw water resources in the municipality have been identified and based on these, the proposals for placement are based. With the help of several contacts in the industry, a simpler design has been made for a water treatment plant with a capacity of 3000 cubic meters of drinking water per day. The result presents some suggestions for placement of a desalination plant.
88

Assessment of a newly developed fouling-resistant low pressure ro membrane using raw and processed high organic surface water

Holmquist, Sonia M. 01 July 2002 (has links)
No description available.
89

Performance evaluation of reverse osmosis brackish water desalination plant with different recycled ratios of retentate

Alsarayreh, Alanood A., Al-Obaidi, Mudhar A.A.R., Al-Hroub, A.M., Patel, Rajnikant, Mujtaba, Iqbal 28 March 2022 (has links)
Yes / Reverse Osmosis (RO) process has become one of the most widely utilised technologies for brackish water desalination for its capabilities of producing high-quality water. This paper emphasis on investigating the feasibility of implementing the retentate recycle design on the original design of an industrial medium-sized multistage and multi-pass spiral wound brackish water RO desalination plant (1200 m³/day) of Arab Potash Company (APC) located in Jordan. Specifically, this research explores the impact of recycling the high salinity stream of the 1st pass (at different recycled percentages) to the feed stream on the process performance indicators include, the fresh water salinity, overall recovery rate, and specific energy consumption. The simulation is carried out using an earlier model developed by the same authors for the specified RO plant using gPROMS suits. This confirmed the possibility of increasing the product capacity by around 3% with 100% recycle percentage of the high salinity retentate stream.
90

Scope and limitations of the irreversible thermodynamics and the solution diffusion models for the separation of binary and multi-component systems in reverse osmosis process

Al-Obaidi, Mudhar A.A.R., Kara-Zaitri, Chakib, Mujtaba, Iqbal 05 February 2017 (has links)
Yes / Reverse osmosis process is used in many industrial applications ranging from solute-solvent to solvent-solvent and gaseous separation. A number of theoretical models have been developed to describe the separation and fluxes of solvent and solute in such processes. This paper looks into the scope and limitations of two main models (the irreversible thermodynamics and the solution diffusion models) used in the past by several researchers for solute-solvent feed separation. Despite the investigation of other complex models, the simple concepts of these models accelerate the feasibility of the implementation of reverse osmosis for different types of systems and variety of industries. Briefly, an extensive review of these mathematical models is conducted by collecting more than 70 examples from literature in this study. In addition, this review has covered the improvement of such models to make them compatible with multi-component systems with consideration of concentration polarization and solvent-solute-membrane interaction.

Page generated in 0.0494 seconds