TRANSPORT MODE OF MEMBRANE DISTILLATION PROCESS AND THE VMD METHOD TODETERMINE THE MEMBRANE CONFIGURATIONAL NUMBER

A vacuum membrane distillation (VMD) method was employed for the direc t determination of configurational number r epsilon/tau for porous mem branes used in the MD process. For the same purpose, the transport mod e was investigated experimentally. Results showed that mass transfer o f the MD process is predominated by Knudsen diffusion in our experimen tal system. Although greatly discrepant from the predicted value based on assumption, the directly obtained r epsilon/tau value correlates w ell with flux, pressure and temperature.