Influence of PGMD module design on the water productivity and energy efficiency in desalination

In this study, five hollow fibre PGMD modules have been tested to investigate the influence of different module designs on water productivity and energy efficiency in desalination. It is found that modules with low hollow fibre packing density and gap channel density had higher flux and better energy performance in terms of lower Specific Thermal Energy Consumption (STEC). Modules with higher hollow fibre packing density and gap channel density showed higher production of permeate and more efficient use of membrane surface area. It is also found that, the module with a more conductive cooling plate had a higher flux and lower STEC, which was mainly attributed to the lower thermal resistance of the cooling plate. The GOR from this study was in the range of 0.07-0.27, which was relatively low compared to other MD studies. This phenomenon was probably due to the small membrane surface area and insufficient internal heat recovery. Further improvements to this hollow fibre PGMD module have been suggested.