I would agree with Don's ...

Published October 31, 2018 15:15 by Terry Scheurman, President at Applied Specialties, Inc.

I would agree with Don's reply and the answer is often simple but complex.

Here is an example of where separation is easy to determine. A power plant had a consolidated wastewater stream that was treated and then concentrated by RO. Permeate was reused and reject went to evap ponds. Maximum reject TDS were 66,000ppm. Into the plant wastewater stream, they added demineralizer regenerant waste at a combined 90,000ppm. Removing the regenerant waste decreased a significant salt load to the RO. Further segregating the phases of the regenerant decreased the volume of total brine waste going to their evap ponds.

This was easy because it was obvious, the combined plant waste stream to the evap ponds was 66,000 and the regenerant waste was 90,000 of nearly 1.5x.