Energy consumption for Brine solution recovery in Direct Contact Membrane Distillation Sothyreak Chhun 1,2,a* , Watsa Khongnakorn 1,2,b , Wirote Youravong 2,3,c 1 Department of Civil Engineering, Faculty of Engineering Prince of Songkla University, Hat Yai, Songkla 90112, Thailand 2 Membrane Science and Technology Research Center, Prince of Songkla University, Hat Yai, Songkla 90112, Thailand 3 Department of Food Technology, Faculty of Agro-Industry, Prince of Songkla University, Hat Yai, 90112, Thailand Email: a* sothyreakchhun@gmail.com , b watsa.k@psu.ac.th , c wirote.y@psu.ac.th Keywords: Direct contact membrane distillation, Hollow fiber membrane, Temperature polarization coefficient, Evaporation efficiency, Energy consumption. Abstract: Direct contact membrane distillation (DCMD) process was applied for brine solution recovery. The energy consumption of the process was evaluated as varying feed temperature and cross flow velocity (CFV). The evaporation efficiency and energy consumption were also studied. The experiments was carried out using a hollow fiber PVDF membrane with pore size of 0.1 µm and NaCl 3.5 %wt as feed solution. The operating feed temperature and CFV were in range of 40 °C-70 °C and 0.14-0.42 m/s (laminar and transition flow region), respectively. The temperature and CFV of permeate were fixed at 20 °C and 1.97 m/s respectively. It was found that the flux rate was in function with the temperature, CFV and temperature polarization coefficient (TPC). The best result in terms of energy consumption and evaporation efficiency were obtained at CFV and temperature of 0.28 m/s and 70 °C about 188.6 W and 41.1 %, respectively. Introduction Direct contact membrane distillation (DCMD) is a membrane separation process driven by vapor pressure gradient across through the microporous hydrophobic membrane. DCMD has been studied to employ in water purification. It has found to achieve in part of treatment at lower temperature preferred which could be save for energy consumption and higher water quality. Termpiyakul et al. [1] studied heat and mass transfer in DCMD under differences concentrations of brine solution. They found that the temperature polarization coefficient increased with increasing feed velocity and concentration. In addition, it is also operated at atmospheric pressure without need to supply pressure energy. As a result, feed temperature is considered as an important process parameter to produce vapor pressure. Evaporation efficiency and energy consumption were investigated by Deshmukh et al [2]. The objective of this paper was to determine the energy consumption and heat loss of the DCMD system for brine recovery and desalination for reverse osmosis (RO). Theory Polyvinylidene fluoride (PVDF) hollow fiber membrane was used to fabricate in 9 mm of diameter module with fibers diameter 1.2/0.7 mm, length 240 mm, giving an effective membrane area of 0.011 m 2 . The membrane module was installed vertically to omit the effect of free convection and to remove air bubble [3]. Brine solution (NaCl solution 3.5 %wt) was used as a feed. The feed temperature and cross flow velocity (CFV, using the laminar and transition flow) were varied in range of 40-70 °C and 0.14-0.42 m/s, respectively. Simultaneously, the temperature of DI water circulated in permeate side was kept constant at 20 °C. Advanced Materials Research Vols. 931-932 (2014) pp 256-260 © (2014) Trans Tech Publications, Switzerland doi:10.4028/www.scientific.net/AMR.931-932.256 All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of TTP, www.ttp.net. (ID: 202.12.73.65-02/05/14,08:53:05)