Experimental study on vacuum membrane distillation based on brine desalination by PVDF

Abstract

Based on polyvinylidene fluoride (PVDF) hollow fiber hydrophobic porous membrane, vacuum membrane distillation desalination test bench was built to study the effects of operating parameters such as temperature of feed solution, flow rate of feed solution, concentration of feed solution and vacuum degree on the performance of vacuum membrane distillation process. Experimental results showed that with an increase in the vacuum degree and temperature of the flux of membrane is increased. While with an increase in the concentration of feed solution of the flux of membrane is decreased and retention rate were essentially the same, with an increase in the flow rate of feed solution of he flux of membrane changed slowly (increase slightly). When temperature of the feed solution was 88°C, the flow rate of feed solution was 270cm/min, the vacuum degree was 0.081MPa, the concentration of feed solution was 5%, the flux of membrane was 14.1kg/ (m2.h), the retention rate was 99.8%, the electrical conductivity of fresh water was maintained at 12us/cm.