Exceeding 90% Recovery with Conventional and Closed-Circuit RO: Results from Parallel Pilot Systems

For inland reverse osmosis (RO) systems, brine disposal is often difficult and costly, and there is significant interest in increasing recovery and reducing brine volumes. The City of Buckeye, AZ owns brackish wells that have trace amounts of arsenic, nitrate, and various metals, and is considering RO treatment for these wells. Stantec performed a pilot study to evaluate the groundwater scaling regime and investigate how conventional vs. advanced flow RO configuration affected achievable recovery. This study showed that, through understanding and control of the scaling chemistry as well as the flow conditions in the pressure vessel array, aggressive recovery rates of 90% or more could be achieved in both a conventional and CCRO system.