Managing Brackish RO Concentrates

Average brackish water RO recovery is about 75% in southern Florida. With an anticipated capacity of 540 mgd by 2025 and increase in recovery to 95% would yield over 100 mgd of potable water. A two phase study was conducted to evaluate possible concentrate management techniques to increase RO recovery. Stage 1 involved a literature review and feasibility analysis and Stage 2 included pilot testing of the chosen method. The test train included RO-perceptive softening to remove concentrated salts-Media filtration-Second Stage RO and blending. The testing proved to produce a combined permeate TDS of 250 mg/L, below the goal of 500 mg/L.