Optimization of operating conditions for a continuous membrane distillation crystallization process with zero salty water discharge

Factors affecting the crystal size distribution were investigated and indicated that the sodium chloride crystals had a narrow size distribution. The feed flow rate and inlet temperature had more influence on the mean crystal size and crystal size distribution, whereas the permeate flow rate and inlet temperature had relatively less effect. Therefore, CMDC operation was found not only to produce a high quality water product but also sodium chloride crystals with a relatively narrow size distribution. These results are beneficial to a better understanding of the CMDC process and improving its performance to realize zero salty water discharge to the environment.