Water recycling from mixed chromic acid waste effluents by membrane technology

Approaching zero discharge waste on site requires economical treatment technologies for the plating industry, recovering high quality rinse water for reuse. The combination of membranes and evaporation could be an efficient way to downsize the cost and the energy intensive evaporation equipment. In this work a combination of membrane processes is evaluated for efficient reduction of the waste water volume before evaporation. A stable process is developed showing that pre-concentration by 51% is possible. Chemical stable membranes are evaluated and optimum process parameters are determined.