Experimental study of hollow fiber permeate gap membrane distillation and its performance comparison with DCMD and SGMD

A hollow fiber Permeate Gap Membrane Distillation (PGMD) module was tested and compared with that operated in Direct Contact Membrane Distillation (DCMD) and Sweeping Gas Membrane Distillation (SGMD) modes. The results showed that the flux increased with increasing feed velocity and feed temperature. The global mass transfer coefficient of PGMD increased initially at low feed temperatures and decreased at high temperatures. Hollow fiber PGMD showed a lower STEC compared to DCMD and SGMD when flux was the same. It also achieved a better balance between flux and specific thermal energy consumption compared to spiral wound and flat sheet PGMD modules.