A novel process for low grade heat driven desalination

Low grade process heat and geothermal energy with temperatures typically below 100. °C are significant untapped environmentally friendly resources for desalination. This article reports on a novel multi-effect distillation (MED) desalination process that is boosted by a multi-stage flashing process. Specifically the low grade heat first heats up the multi-effect distillation plant and is then maximally exploited through a multi-stage flashing process, with the produced steam of which being judiciously introduced into the multi-effect distillation plant for enhanced freshwater production. Compared with optimized conventional MED processes, the performance improvement is up to around 50% better in terms of freshwater production, with a modest increase in the pumping power consumption and 4% to 6% decrease in the specific capital cost. © 2014 Elsevier B.V.