Driving force and activation energy in air-gap membrane distillation process

The present study investigated the impact of the driving force (Delta p) on the transport properties. All the experiments and calculations were performed for air-gap membrane distillation (AGMD). In the course of the experiments, it was found that an identical value of Delta p could be attained by applying different values of feed and permeate temperatures. It was highlighted that constant values of water fluxes could be achieved using the constant driving force created by different temperatures. Moreover, the relation between ln(J(H2O)) and 1/T-f was shown to be linear only for the J(H2O) created at Delta T = T-f -T-p > 35 K. This work's significant finding was to highlight the limitation of the Arrhenius-type equation applied in the activation energy calculations. (C) 2015 Institute of Chemistry, Slovak Academy of Sciences