Process introduction and techno-economic analysis on pure salt recovery crystallization for high salinity wastewater

It is of great importance to provide optimal pure salt recovery crystallization process designs and maximize recovery of pure salts at the lowest cost while achieving zero liquid discharge for the high salinity wastewater at coal chemical and other industries.In this paper,various typical pure salt recovery crystallization processes for high salinity wastewater were described and discussed.Exemplary pure salt recovery process designs were then provided and discussed with a high salinity coal chemical wastewater as the feed stream.Quantitative techno-economic analysis was further performed for the thermal and the membrane-based pure salt recovery crystallization processes.The results indicate that the membrane-based process shows 30% higher capital cost but saves 30% operation cost as a result of 37.8 higher percentage recovery rate of pure salts.It is concluded that the membrane-based process is a better solution in this case especially when the disposal cost of the mixed salt waste is high.