Evaluation of the Specific Energy Consumption of Sea Water Reverse Osmosis Integrated with Membrane Distillation and Pressure–Retarded Osmosis Processes with Theoretical Models

Membranes

Zhen Wang¹  Geng-Sheng Lin¹  Wei-Zhi Huang¹  Kuo-Lun Tung¹  Shao-Chi Tsai²  Ching-Jung Chuang² 

[1] Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan;R&D Center for Membrane Technology, Department of Chemical Engineering, Chung Yuan Christian University, Taoyuan 320, Taiwan;

关键词: reverse osmosis;    pressure-retarded osmosis;    membrane distillation;    process integration;    specific energy consumption;   

DOI  :  10.3390/membranes12040432

来源: DOAJ

【 摘 要 】

In this study, theoretical models for specific energy consumption (SEC) were established for water recovery in different integrated processes, such as RO-PRO, RO-MD and RO-MD-PRO. Our models can evaluate SEC under different water recovery conditions and for various proportions of supplied waste heat. Simulation results showed that SEC in RO increases with the water recovery rate when the rate is greater than 30%. For the RO-PRO process, the SEC also increases with the water recovery rate when the rate is higher than 38%, but an opposite trend can be observed at lower water recovery rates. If sufficient waste heat is available as the heat source for MD, the integration of MD with the RO or RO-PRO process can significantly reduce SEC. If the total water recovery rate is 50% and MD accounts for 10% of the recovery when sufficient waste heat is available, the SEC values of RO, RO-PRO, RO-MD and RO-MD-PRO are found to be 2.28, 1.47, 1.75 and 0.67 kWh/m³, respectively. These critical analyses provide a road map for the future development of process integration for desalination.

【 授权许可】

Unknown