Desalitech and CH2M are to supply a ReFlex Max system for a six-month pilot study to be conducted at Orange County Water District’s Groundwater Replenishment System (GWRS).

The study will evaluate Desalitech Closed Circuit Desalination (CCD) technology for treating reverse osmosis concentrate, and will aim to maximise overall water recovery, minimise the volume of concentrate to be disposed of, and reduce energy consumption.

The pilot will run at the 100 MGD (380,000 m3/d) GWRS in Fountain Valley, California, US, where a three-stage reverse osmosis system achieves 85 per cent recovery.

“Orange County plans to expand to 130 MGD (500,000 m3/d) in the near future, which, at 85 per cent recovery, means we’ll be disposing of 23 MGD (87,000 m3/d) of concentrate. Technologies like CCD could enable us to recover more of that water,” said Orange County Water District research and development director, Megan Plumlee.

The Orange County Water District GWRS is the world’s largest advanced water purification system of its kind for potable reuse, taking treated municipal wastewater that would otherwise be discharged into the Pacific Ocean, and purifying it by a three-step advanced purification process consisting of micro filtration, reverse osmosis, and ultraviolet light with hydrogen peroxide. It produces high quality water to recharge the Orange County Groundwater Basin.

“CH2M recognises the potential for Desalitech CCD technology to be a game changer for a wide range of desalination applications, and in particular to increase reverse osmosis energy efficiency and water recovery, in a reliable manner, while reducing the costs associated with concentrate management. We look forward to partnering with Desalitech and Orange County Water District in the pilot testing,” said global technology leader, desalination, at CH2M, Jim Lozier.