https://cronfa.swan.ac.uk/Record/cronfa48864/Download/0048864-07032019141310.pdf

Reverse osmosis desalination: A state-of-the-art review

Advances in highly permeable reverse osmosis (RO) membranes have enabled desalting operations, in which it is practically feasible for the applied pressure to approach the osmotic pressure of the exit brine stream. However, energy cost remains a major contributor to the total cost of water produced by RO membrane desalination. Reduction of the overall cost of water production represents a major challenge and, in the present work, various elements of water production cost are evaluated from the viewpoint of optimization, with respect to various costs (energy, membrane area and permeability, brine management, and pressure drop), as well as the important thermodynamic cross-flow constraint, utilization of energy recovery devices, and operational feed and permeate flow rate constraints. More specifically, in the present study, an approach to the optimization of product water recovery at pressures that approach the osmotic pressure of the exit brine stream is presented via several simple RO process models that...

/pdf/effect-of-thermodynamic-restriction-on-energy-cost-144grxno66.pdf

Effect of Thermodynamic Restriction on Energy Cost Optimization of RO Membrane Water Desalination

Multi-objective optimization of RO desalination plants

Optimum design of reverse osmosis system under different feed concentration and product specification

Energy consumption is a key factor which influences the freshwater production cost in reverse osmosis (RO) process. Energy recovery and reuse options have already been very well explored in the current desalination industry. Achieving minimum theoretical specific energy consumption for water recovery is not feasible due to effects of concentration polarization, membrane fouling and hydraulic resistance to permeate flow. Due to these limitations, energy recovery along with water recovery can be a better alternative to improve energy consumption and economics of the RO process both in small and large scale applications. This paper reviews currently available process configurations, operating strategies, and discusses potential pathways to recover and recycle energy and water to improve the performance of the RO process.

Energy consumption and recovery in reverse osmosis

Optimum design of reverse osmosis seawater desalination system considering membrane cleaning and replacing

Membrane technology was widely used in the field of oil-water separation. In the process of water-in-oil emulsion treatment, surface contamination of hydrophobic and lipophilic membranes was a difficult problem. Therefore, the effect of hydrophobic membrane surface micro-rough structure on oil-water separation performance and its anti-fouling behavior has been investigated as a major focus of current research. Superhydrophobic-superoleophilic polyvinylidene fluoride (PVDF) membranes with micron-submicron hierarchical structure were prepared by combining thermally induced phase separation (TIPS) with rolling embossing. The influence of the roller temperature on the structure and performance of the membrane were discussed. The best achieved superhydrophobicity with a high water contact angle (WCA) of 154.8° and rolling angle (SA) of 1.9°, which was similar with lotus-effect. Meanwhile, the N2 flux was 197 L m−2 s−1 and LEP was 4.08 bar. Besides, the tensile strength of PVDF membrane was 1.89 MPa. The embossed membrane showed good lipophilicity, and the residence time of kerosene on the membrane surface was only 0.14 s. PVDF membranes with lotus leaf effect showed excellent demulsification performance and high recyclability in water in oil emulsion. The oil flux and rejection rate were 1258 L m−2 h−1 and 99.14%, respectively. In the separation experiment of PVDF membranes in diesel emulsion containing inorganic pollutant CaCO3, the results showed that the anti-fouling effect of PVDF membranes by cross-flow filtration method was obviously better than that by dead-end filtration method. When the operating temperature and pressure were 0.1 MPa and 45 °C, respectively, embossed membrane showed relatively excellent separation performance in cross-flow filtration. This study provided some guidance for the anti-fouling performance of roughened surface superhydrophobic-superoelophilicity membrane in oil-water separation experiment. 

Anti-fouling performance investigation of micron-submicron hierarchical structure PVDF membranes in water-in-oil emulsion separation

Experiment and Modeling of Hydrophobic Membranes for Removal of Organics from Aqueous Solution by Pervaporation

The optimal scheduling of multi-product batch process is studied. The relationship between production scale and production cost is analyzed. A new mathematics model is proposed which takes the maximum profit as objective function, which can be solved by the modified genetic algorithm (GA) with mixed coding (sequence coding and decimal coding) developed by us. The PMX crossover and reverse mutation are used for the sequence coding. At the same time, the arithmetic crossover and heteropic mutation are used for the decimal coding. An example is solved to demonstrate the effectiveness of the method.

Lian-Ying Wu

Papers

Optimum design of reverse osmosis system under different feed concentration and product specification

Optimum design of reverse osmosis seawater desalination system considering membrane cleaning and replacing

Anti-fouling performance investigation of micron-submicron hierarchical structure PVDF membranes in water-in-oil emulsion separation

Experiment and Modeling of Hydrophobic Membranes for Removal of Organics from Aqueous Solution by Pervaporation

Solving batch production scheduling using genetic algorithm