Modeling on the distillate fluxes of DCMD and VMD in desalination

• Main Authors: Tzu-Pei Liao, 廖子霈
• Other Authors: Tung-Wen Cheng
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/94059062941747959858

碩士 === 淡江大學 === 化學工程與材料工程學系碩士班 === 100 === The objectives of this study included the flux estimation of DCMD and VMD in seawater desalination and their comparisons, and aimed to investigate the optimal operating conditions for seawater desalination. The operating parameters in the simulation included the feed flow rate, temperature and concentration. The simulation results based on considering the combination of Dusty-Gas model with the seawater properties agree very well with the experimental data. The results also show that the temperature polarization has a significant influence on the flux. The polarization phenomena in the VMD system can be easier improved to increase the distillate flux. However, the operating cost of VMD increases with the increase of distillate flux. The cost evaluation shows that the DCMD system is more economic than the VMD system. Both the temperature and concentration phenomena can be reduced by increasing the flow rates in the DCMD system. It is noted that increasing the feed side flow rate also enhances the thermal efficiency, while increasing the flow rate in distillate side will raise the heat conduction through the membrane and result in lowering the thermal efficiency.