Performance evaluation of ePTFE and PVDF flat-sheet module direct contact membrane distillation

摘要

This paper reports experiments using a flat-sheet module with 0.18 , 0.45 mm ePTFE (expandednpolytetrafluoroethylene) and PVDF (polyvinylidene fluoride) membranes to show the effects ofnmembrane properties, salt concentration and fluid hydrodynamics on the permeate flux and saltnrejection of DCMD (direct contact membrane distillation). A theoretical prediction of the permeatenflux was carried out, and was in close agreement with the experimental results. In addition, thenenergy integration of the process was also analyzed in order to evaluate module design tonincrease energy efficiency. According to the simulated results of the energy integration design,na combination of simultaneous cooling of the permeate stream and an additional heat exchangernto lower the temperature of the permeate stream not only enhances the MD flux, but alsonreduces energy consumption.