The Experts below are selected from a list of 9339 Experts worldwide ranked by ideXlab platform
Taishung Chung - One of the best experts on this subject based on the ideXlab platform.
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design of zero liquid discharge Desalination zldd systems consisting of freeze Desalination Membrane distillation and crystallization powered by green energies
Desalination, 2019Co-Authors: Kangjia Lu, Jian Chang, Zhen Lei Cheng, Taishung ChungAbstract:Abstract Zero liquid discharge Desalination (ZLDD) is a sustainable solution to the global water scarcity problem. It provides high water recovery, zero waste generation and valuable salt production. In this work, a mathematical model of a novel ZLDD system that consists of freeze Desalination (FD) and Membrane distillation-crystallization (MD-C) has been developed based on the theories of heat and mass transfer as well as experimental results. To improve the energy efficiency of the system, effects of important parameters, such as (1) the feed temperature, concentration, and distillate temperature of MD and (2) the recovery ratio of FD on system operating curves and energy consumptions have been systematically investigated with the aid of mathematical modelling. In addition, the potential of using green energies to power this hybrid system has been explored. For a lab-scale hybrid ZLDD system operating at optimized conditions with a daily seawater processing capacity of 72 kg, 50% of its heating energy can be supported by a 50.5 m2 solar panel and its cooling energy can be 100% provided by re-gasification of 207-kg liquefied natural gas (LNG). This work may provide useful guidance in designing a low-cost FD-MD-C hybrid system for ZLDD.
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a conceptual demonstration of freeze Desalination Membrane distillation fd md hybrid Desalination process utilizing liquefied natural gas lng cold energy
Water Research, 2012Co-Authors: Peng Wang, Taishung ChungAbstract:The severe global water scarcity and record-high fossil oil price have greatly stimulated the research interests on new Desalination technologies which can be driven by renewable energy or waste energy. In this study, a hybrid Desalination process comprising freeze Desalination and Membrane distillation (FD-MD) processes was developed and explored in an attempt to utilize the waste cold energy released from re-gasification of liquefied natural gas (LNG). The concept of this technology was demonstrated using indirect-contact freeze Desalination (ICFD) and direct-contact Membrane distillation (DCMD) configurations. By optimizing the ICFD operation parameters, namely, the usage of nucleate seeds, operation duration and feed concentration, high quality drinkable water with a low salinity ∼0.144 g/L was produced in the ICFD process. At the same time, using the optimized hollow fiber module length and packing density in the DCMD process, ultra pure water with a low salinity of 0.062 g/L was attained at a condition of high energy efficiency (EE). Overall, by combining FD and MD processes and adopting the optimized operation parameters, the hybrid FD-MD system has been successfully demonstrated. A high total water recovery of 71.5% was achieved, and the water quality obtained met the standard for drinkable water. In addition, with results from specific energy calculation, it was proven that the hybrid process is an energy-saving process and utilization of LNG cold energy could greatly reduce the total energy consumption.
Meni Wanunu - One of the best experts on this subject based on the ideXlab platform.
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High permeability sub-nanometre sieve composite MoS_2 Membranes
Nature Communications, 2020Co-Authors: Bedanga Sapkota, Wentao Liang, Armin Vahidmohammadi, Rohit Karnik, Aleksandr Noy, Meni WanunuAbstract:Molybdenum disulfide Membranes are attractive for filtration of nanoscale species but should be optimized for application. Here, the authors report composite Membranes with tunable surface charge, pore size and interlayer spacing, achieving efficient filtration of small-molecule dyes and osmosis. Two-dimensional Membranes have gained enormous interest due to their potential to deliver precision filtration of species with performance that can challenge current Desalination Membrane platforms. Molybdenum disulfide (MoS_2) laminar Membranes have recently demonstrated superior stability in aqueous environment to their extensively-studied analogs graphene-based Membranes; however, challenges such as low ion rejection for high salinity water, low water flux, and low stability over time delay their potential adoption as a viable technology. Here, we report composite laminate multilayer MoS_2 Membranes with stacked heterodimensional one- to two-layer-thick porous nanosheets and nanodisks. These Membranes have a multimodal porous network structure with tunable surface charge, pore size, and interlayer spacing. In forward osmosis, our Membranes reject more than 99% of salts at high salinities and, in reverse osmosis, small-molecule organic dyes and salts are efficiently filtered. Finally, our Membranes stably operate for over a month, implying their potential for use in commercial water purification applications.
Wansuk Choi - One of the best experts on this subject based on the ideXlab platform.
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layer by layer assembly of graphene oxide nanosheets on polyamide Membranes for durable reverse osmosis applications
ACS Applied Materials & Interfaces, 2013Co-Authors: Wansuk Choi, Jungkyu Choi, Joona BangAbstract:Improving Membrane durability associated with fouling and chlorine resistance remains one of the major challenges in Desalination Membrane technology. Here, we demonstrate that attractive features of graphene oxide (GO) nanosheets such as high hydrophilicity, chemical robustness, and ultrafast water permeation can be harnessed for a dual-action barrier coating layer that enhances resistance to both fouling and chlorine-induced degradation of polyamide (PA) thin-film composite (TFC) Membranes while preserving their separation performance. GO multilayers were coated on the PA-TFC Membrane surfaces via layer-by-layer (LbL) deposition of oppositely charged GO nanosheets. Consequently, it was shown that the conformal GO coating layer can increase the surface hydrophilicity and reduce the surface roughness, leading to the significantly improved antifouling performance against a protein foulant. It was also demonstrated that the chemically inert nature of GO nanosheets enables the GO coating layer to act as a ch...
Sanchuan Yu - One of the best experts on this subject based on the ideXlab platform.
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improving fouling resistance and chlorine stability of aromatic polyamide thin film composite ro Membrane by surface grafting of polyvinyl alcohol pva
Desalination, 2015Co-Authors: Qing Chen, Lizhong Wang, Sanchuan YuAbstract:Abstract Improving fouling resistance and chlorine stability of aromatic polyamide (PA) thin-film composite (TFC) reverse osmosis Membrane is still of considerable need in Desalination Membrane technology. Here, we reported the chemical linkage of neutral hydrophilic polymer polyvinyl alcohol (PVA) on the surface of a commercial PA TFC Membrane through a single step of grafting with potassium persulfate as thermal dissociation initiator and its role on the improvement of Membrane resistance to both chlorine and fouling. Membrane characterization was conducted through ATR-FTIR spectroscopy, SEM, AFM, measurements of streaming potential and contact angle and cross-flow permeation tests. It was found that Membrane surface became smoother, more hydrophilic and less charged after modification and the modified Membrane exhibited an increased slat rejection, a slightly declined water flux and improved fouling resistances to the model foulants of bovine serum albumin (BSA), sodium dodecyl sulfate (SDS) and dodecyltrimethyl ammonium bromide (DTAB). The chlorine exposure tests under accelerated conditions also indicated that the Membrane chlorine stability has been enhanced effectively. The PVA molecules on the Membrane surface could effectively enhance Membrane anti-adsorption capability and prevent the underlying polyamide backbones from chlorine attack, and thereby improving Membrane resistance to both fouling and chlorine.
Bedanga Sapkota - One of the best experts on this subject based on the ideXlab platform.
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High permeability sub-nanometre sieve composite MoS_2 Membranes
Nature Communications, 2020Co-Authors: Bedanga Sapkota, Wentao Liang, Armin Vahidmohammadi, Rohit Karnik, Aleksandr Noy, Meni WanunuAbstract:Molybdenum disulfide Membranes are attractive for filtration of nanoscale species but should be optimized for application. Here, the authors report composite Membranes with tunable surface charge, pore size and interlayer spacing, achieving efficient filtration of small-molecule dyes and osmosis. Two-dimensional Membranes have gained enormous interest due to their potential to deliver precision filtration of species with performance that can challenge current Desalination Membrane platforms. Molybdenum disulfide (MoS_2) laminar Membranes have recently demonstrated superior stability in aqueous environment to their extensively-studied analogs graphene-based Membranes; however, challenges such as low ion rejection for high salinity water, low water flux, and low stability over time delay their potential adoption as a viable technology. Here, we report composite laminate multilayer MoS_2 Membranes with stacked heterodimensional one- to two-layer-thick porous nanosheets and nanodisks. These Membranes have a multimodal porous network structure with tunable surface charge, pore size, and interlayer spacing. In forward osmosis, our Membranes reject more than 99% of salts at high salinities and, in reverse osmosis, small-molecule organic dyes and salts are efficiently filtered. Finally, our Membranes stably operate for over a month, implying their potential for use in commercial water purification applications.