Download or read book A new method of seawater desalination via acrylic acid based hydrogels Synthesis characterisation and experimental realisation written by Höpfner, Johannes and published by KIT Scientific Publishing. This book was released on 2014-02-04 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: The scarcity of potable water is a great challenge. It may be resolved by the desalination of seawater. In this work, the possibilities of a new desalination technique using polymeric hydrogels as a separation medium for water and salt is explored. The bound charges in such a polymeric network prevent salt from entering it - under pressure the desalinated water is released from the gel. It is demonstrated that the method is viable and the influence of various process parameters investigated.

Download or read book Membrane Based Desalination written by Enrico Drioli and published by IWA Publishing. This book was released on 2011-04-14 with total page 247 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reverse osmosis is the dominant technology in water desalination. However, some critical issues remain open: improvement of water quality, enhancement of the recovery factor, reduction of the unit water cost, minimizing the brine disposal impact. This book aims to solve these problems with an innovative approach based on the integration of different membrane operations in pre-treatment and post-treatment stages. Membrane-Based Desalination: An Integrated Approach (acronym MEDINA) has been a three year project funded by the European Commission within the 6th Framework Program. The project team has developed a work programme aiming to improve the current design and operation practices of membrane systems used for water desalination, trying to solve or, at least, to decrease the critical issues of sea and brackish water desalination systems. In the book, the main results achieved in the nine Work Packages constituting the project will be described, and dismissed by the leaders of the various WPs. The following areas are explored in the book: the development of advanced analytical methods for feed water characterization, appropriate fouling indicators and prediction tools, procedures and protocols at full-scale desalination facilities; the identification of optimal seawater pre-treatment strategies by designing advanced hybrid membrane processes (submerged hollow fibre filtration/reaction, adsorption/ion exchange/ozonation) and comparison with conventional methods; the optimisation of RO membrane module configuration, cleaning strategies, reduction of scaling potential by NF; the development of strategies aiming to approach the concept of Zero Liquid Discharge (increasing the water recovery factor up to 95% by using Membrane Distillation - MD; bringing concentrates to solids by Membrane Crystallization or Wind Intensified Enhanced Evaporation) and to reduce the brine disposal environmental impact and cost; increase the sustainability of desalination process by reducing energy consumption (evaluation of MD, demonstration of a new energy recovery device for SWRO installations) and use of renewable energy (wind and solar). Colour figures (PDF, 6MB) Visit the IWA WaterWiki to read and share material related to this title: http://www.iwawaterwiki.org/xwiki/bin/view/Articles/WaterdesalinationandEuropeanresearch

Download or read book Algal Blooms and Membrane Based Desalination Technology written by LOREEN OPLE. VILLACORTE and published by CRC Press. This book was released on 2018-09-27 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seawater desalination is rapidly growing in terms of installed capacity ( 80 million m3/day in 2013), plant size and global application. An emerging threat to this technology is the seasonal proliferation of microscopic algae in seawater known as algal blooms. Such blooms have caused operational problems in seawater reverse osmosis (SWRO) plants due to clogging and poor effluent quality of the pre-treatment system which eventually forced the shutdown of the plant to avoid irreversible fouling of downstream SWRO membranes. As more extra large SWRO plants (>500,000 m3/day) are expected to be constructed in the coming years, frequent chemical cleaning (>1/year) of SWRO installations will not be feasible, and more reliable pre-treatment system will be required. To maintain stable operation in SWRO plants during algal bloom periods, pre-treatment using ultrafiltration (UF) membranes has been proposed. This thesis addresses the effect of algal blooms on the operation of UF pre-treatment and SWRO. Experimental investigations demonstrated that marine algal blooms can impact the backwashability of UF and can accelerate biological fouling in RO. However, it is unlikely that algae themselves are the main causes of fouling but rather the transparent exopolymer particles (TEPs) that they produce. To better monitor TEPs, a new method capable of measuring TEP as small as 10 kDa was developed and showed that TEPs can be effectively removed by UF pre-treatment prior to SWRO. This work also demonstrated that although TEPs and other algal-derived material (AOM) are very sticky and can adhere to UF and RO membranes, adhesion can be much stronger on membranes already fouled with AOM. Moreover, a model was developed to predict the accumulation of algal cells in capillary UF membranes which further demonstrated that the role of algal cells in UF fouling is not as significant as that of AOM and TEPs. Overall, this study demonstrates that better analytical methods and tools are essential in elucidating the adverse impacts of algal blooms in seawater on the operation of membrane-based desalination plants (UF-RO). It also highlighted the importance of developing effective pre-treatment processes to remove AOM from the raw water and reduce the membrane fouling potential of the feed water for downstream SWRO membranes.

Download or read book Seawater Desalination by Reverse Osmosis written by Kok Teng Chua and published by . This book was released on 2002 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synthesis and Characterization of Acrylic Acid containing Dextran Hydrogels written by 邱信程 and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Desalination Technologies written by Iqbal M. Mujtaba and published by Elsevier. This book was released on 2022-06-28 with total page 662 pages. Available in PDF, EPUB and Kindle. Book excerpt: Desalination Technologies: Design and Operation sets the scene for desalination technologies as a long-term solution to freshwater demand by analyzing the current demand for water, available water resources and future predicted demand. The book captures recent developments in thermal desalination (multistage flash desalination, multi-effect evaporation, vapor compression), membrane desalination (forward osmosis, reverse osmosis, pressure retarded, electrodialysis, membrane distillation, ultra-, nano-, and micro-filtration), and alternative processes such as freezing and ion exchange. Both dynamic and steady state models (from short cut, simple, to detail) of various desalination processes are discussed. The book is intended for (under)graduate students in chemical engineering and postgraduate researchers and industrial practitioners in desalination. - Provides the fundamentals of different desalination processes - Includes desalination modeling from short and simple, to detailed and more advanced - Discusses desalination optimization and synthesis to reduce environmental impact - Handles thermo-physical property models and correlations - Includes case studies to give a clearer understanding of desalination

Download or read book Study on Hydrodynamic Characteristics of the Raft type Wave Powered Desalination Device written by Siming Zheng and published by Springer. This book was released on 2017-09-06 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis proposes a new raft-type wave-powered desalination device that can convert wave power into hydraulic energy and use reverse osmosis (RO) to directly desalinate seawater. Both analytical and numerical methods are used to study the hydrodynamic characteristics of the device. Further, the thesis investigates the maximum power extraction and multiple parameter effects on power absorption and averaged permeate water flux. Lastly, it proposes and assesses two power extraction enhancing strategies. The thesis offers a valuable and important reference guide to ocean-wave-and-structure interaction and wave-powered seawater desalination for scientists and engineers alike.

Download or read book Reverse Osmosis and Ultrafiltration Membrane Surface Nano Structuring with Tethered Hydrophilic Polymer Layers for Seawater Desalination written by Soomin Kim and published by . This book was released on 2020 with total page 247 pages. Available in PDF, EPUB and Kindle. Book excerpt: A systematic investigation of membrane surface nano-structuring (SNS) with surface tethered hydrophilic polymer layers was conducted in order to mitigate fouling of reverse osmosis (RO) and ultrafiltration (UF) membranes and tune membrane performance in seawater desalination. Surface tethered hydrophilic polymer (i.e., polyacrylic acid (PAA)) layers were synthesized onto base polysulfone (PSf) UF and polyamide (PA) thin film composite (TFC) RO membranes via membrane surface activation with an atmospheric pressure plasma (APP), followed by graft polymerization (GP) of acrylic acid. Both APP surface activation and GP conditions impacted the structure of the synthesized tethered PAA layers and RO membrane desalination performance. Detailed characterization of tethered PAA chain extension length via atomic force microscopy (AFM) based force spectroscopy (FS) revealed that the number average molecular weight of the synthesized tethered PAA chains was estimated to be in the range of 13,000-35,000 with chain-chain separation of 1.5-2.4 nm. Extension of the tethered PAA chains in DI water was significantly greater in DI water than in high salinity aqueous environment. UF fouling stress tests with alginic acid in high salinity water and post-cleaning with non-saline water demonstrated permeability restoration of up to 90-100% for a surface nano-structured (SNS)-PAA-PSf membrane relative to 50-70% for the native PSf membrane. Synthesized SNS-PAA-PA BWRO and SWRO membranes having water and salt permeability coefficient in the range of 2.3 - 3.4 L m-2 h-1 bar-1 and 0.15 - 0.54 L m-2 h-1 revealed that membrane surface structuring with a tethered PAA layer enabled tuning membrane performance (in terms of Lp and B) to achieve water/salt selectivity (evaluated as Lp:B ratio) that was significantly higher (by up to 56%) relative to the base PA membranes. It was demonstrated that, depending on APP surface activation and GP conditions, PA TFC membranes could be tuned to have essentially the same salt rejection over a wide permeability range or a given permeability over a range of salt rejection. It was also shown that membrane performance could be achieved that overcomes the permeability-selectivity trade-off. Lastly, the present study developed an approach to scale up the APP surface activation and GP process by performing membrane surface nano-structuring for large PA TFC flat sheet membranes that are suitable for fabricating 2.5" x 21" spiral wound RO elements.

Download or read book A Theoretical and Experimental Study of Seawater Desalination Using Dewvaporation written by Bassem Mustapha Hamieh and published by . This book was released on 2001 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design and Characterization of Salicylic Acid based Hydrogels for Protein Delivery Applications written by Bahar Demirdirek and published by . This book was released on 2016 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: Combination drug delivery has received much attention in the pharmaceutical industry to meet the need for increased efficacy and improved patient compliance. Hydrogels are cross-linked networks of hydrophilic polymers that resembles natural tissue and thus successfully developed for drug delivery applications. In three separate chapters, this dissertation describes novel salicylic acid-based hydrogel systems that concurrently deliver salicylic acid as well as the encapsulated protein. The hydrogels systems described herein are formed via physically and chemically cross-linking techniques. First, salicylic acid-based poly(anhydride-esters) were physically cross-linked with poly(N-isopropylacrylamide-co-acrylic acid) via a solvent-casting technique to form injectable hydrogel systems. The physical interactions between these polymer systems were characterized by Fourier transform infrared spectroscopy. Bovine serum albumin, a representative protein, was successfully incorporated into the hydrogel systems. The release profiles of both salicylic acid and bovine serum albumin were ascertained. Second, salicylic acid-based poly(anhydride-esters) were physically cross-linked with poly(acrylic acid) to develop pH-sensitive hydrogels for oral protein delivery. These systems were characterized using spectroscopic techniques such as Fourier transform infrared spectroscopy. Insulin was incorporated into these systems, release of both insulin and salicylic acid was determined to be pH-dependent. The physical and chemical stability of insulin was characterized following release from the hydrogel system. In addition, these systems displayed mucoadhesive behavior which may further enable insulin bioavailability. The results suggest that these systems may be useful for oral administration of insulin and salicylic acid. Third, salicylic acid was chemically incorporated into hydrogel systems via attachment of salicylic acid to an itaconate moiety followed by cross-linking using acrylic acid and poly(ethylene glycol)-diacrylate via UV. The structure, swelling behavior, pore structure, salicylic acid release, rheological, and mucoadhesion behavior of these hydrogels were studied. These hydrogels systems showed pH-responsive behavior: collapsing at acidic pH levels and leading to slower salicylic acid release, and swelling at higher pH conditions leading to salicylic acid release within 24 hours. Pore structure analysis showed a promising pore size for physically encapsulating of proteins. In conclusion, these results suggested that these systems can potentially be used in combination delivery of proteins and salicylic acid.

Download or read book Desalination written by Irena A. Urbonienė and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reviews research in the field of desalination including the growth of scientific and commercial interest to cogenerative and hybrid technologies for desalination and power generation; Membrane Distillaion (MD) process as a new membrane technology used for desalination and recycling; and, more.

Download or read book A New Method of the Desalination of the Sea Water written by Michael Shoikhedbrod and published by . This book was released on 2018-09-24 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hydrogels written by Fabricio Vitor Câmara and published by Nova Science Publishers. This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrogels are polymeric networks with three-dimensional configurations capable of imbibing high amounts of water or biological fluids. The application of hydrogels technology is being widely used in the pharmaceutical industry as drug delivery systems. In this book, the authors present current research in the study of the synthesis, characterisation and applications of hydrogels. Topics include the synthesis of protein-based hydrogels for biomedical applications; the role of hydrogels in the development of artificial bone substitutes; protein-based hydrogels from fish industrialisation wastes; silk fibroin hydrogels; PVP-Based hydrogels; and the tribological properties of polyvinyl alcohol hydrogels as artificial articular cartilage.

Download or read book Synthesis and Characterization of Poly acrylic Acid Based Microgels for Formulation Applications written by Nettraporn Doungsong and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mechanistic Modeling and Experimental Analysis of Direct Contact Membrane Distillation for Seawater Desalination written by Badr Abdulla Salem Bin Ashoor Al-Mahri and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Material Design and Molecular Engineering of Hydrogels for Solar Desalination written by Xingyi Zhou and published by . This book was released on 2021 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: Growing concern over water scarcity leads to increased research interest in advanced water purification technologies. Solar desalination, which utilizes solar energy to separate water and impurities through vaporization, enables the utilization of sustainable solar energy and abundant seawater to alleviate water scarcity. However, the essential process of solar desalination to remove impurities is energy-intensive. The vapor generation rate is limited due to insufficient solar absorption and thermal loss, lowering the freshwater production yield. Diffuse natural sunlight cannot satisfy the intrinsic energy consumption for rapid water vaporization. Therefore, developing new material platforms that can simultaneously provide high solar absorption, effective energy utilization, and low energy consumption for water vaporization to achieve highly efficient solar desalination under natural sunlight is anticipated. This dissertation adopts hydrogels as the new material platform for seawater desalination based on solar vapor generation (SVG). The unique water state in hydrogels could reduce energy consumption for water vaporization, facilitating vapor generation. To enable hydrogel materials for solar desalination as the vapor generators, rationally material and structural designs, as well as polymer network engineering are applied to achieve highly efficient freshwater production under natural conditions. Hydrogel-based solar vapor generators are constructed by introducing solar absorbers into polymeric networks of hydrogels to enable solar energy harvesting and conversion, providing thermal energy for vapor generation. To overcome the slow swollen rate of hydrogels during interfacial evaporation, different water pathways are constructed in hydrogel-based solar vapor generators to transport water to the evaporation surface for continuous vapor generation (Chapter 3). Moreover, the utilization of solar absorbers with different sizes and dimensions in hydrogels influences the water management and energy utilization efficiency of solar desalination, providing possibilities for enhanced SVG performance. The water state in hydrogels defines the vaporization behavior of water. Thus, the polymeric networks of hydrogels can be architected to tune the water state and further reduce the energy consumption of water vaporization. Polymeric chains with different hydrophilic functional groups are used to tailor the water-polymer interaction, varying the water state and phase change behaviors. Different polymeric networks, such as interpenetrating networks and copolymer networks, could be constructed for effective water management and further reduced evaporation energy consumption (Chapter 4). By incorporating functional components, the hydrogel-based solar vapor generators have also been endowed with multiple functionalities, such as antifouling, self-cleaning, and thermal responsiveness, to improve water collection and enable freshwater production from other water sources (Chapter 5). Finally, the development of hydrogel-based solar vapor generators is summarized and possible future directions are provided (Chapter 6)

Download or read book Materials Design and Surface Engineering of Functional Hydrogels for Solar Desalination and Water Purification written by Youhong Guo and published by . This book was released on 2021 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water scarcity caused by the growing population and pollution in the wake of natural disasters or supply system damage is a severe threat to our society. Thermal and membrane-based technologies have been developed to deliver clean water via seawater desalination and wastewater recycling; however, the requirements of high energy consumption and frequent maintenance of infrastructures have raised a barrier for off-grid regions. Solar-powered distillation has regained attention as a potential solution to water shortage because solar energy dwarfs all other fossil-based energy resources in abundance and environmental benignity. A feasible solar-assisted water purification system not only requires scientific breakthroughs to enable efficient energy capture/conversion and a high rate of clean water production but also needs to be affordable for communities that suffer from economic water scarcity. Hydrogels are an emerging material platform for applications in sustainable water-energy-environmental nexus because gelation chemistry endows them with tunable physicochemical properties and ease of integration with versatile functionalities. This Dissertation focuses on designing hydrogel materials for solar desalination and water purification technologies. First, solar-absorbing nanoparticles are introduced into the hydrogel matrix to efficiently harvest and convert solar energy, powering water evaporation within molecular meshes. The energy utilization and water transport of the systems are investigated based on tuning polymer-water and polymer-particle interactions in hydrogel networks. Next, since evaporation occurs at the hydrogel-air interface, the surface property of hydrogels plays a vital role in the interfacial evaporation process. Taking advantage of intermolecular interactions between polymer chains and solvents, the surface topography of hydrogel evaporators can be tailored in nanoscale to achieve an enhanced water evaporation process. Furthermore, through chemical functionalization, surface wettability can be regulated to boost water evaporation performance. Last, by modifying the functional groups on polymer backbones and absorbers, heavy metal-ion adsorption, antibacterial, and anti-biofouling features are incorporated into hydrogel evaporators. It is anticipated that the studies presented can promote a better understanding of the water evaporation behavior at the hydrogel-air interface and inspire the future design of solar distillation devices/systems with higher clean water production and lower cost, overcoming the dependency on electricity supply to achieve decentralized water purification