LACSD signs up Desalitech for chloride‑removal test
Desalination system developer Desalitech is to support a pilot project with the Los Angeles County Sanitation Districts (LACSD) to upgrade two Santa Clarita Valley wastewater treatment plants in order to meet state‑mandated chloride limits, the company announced on 2 October 2013.The State of California has determined that high levels of chloride are harming salt‑sensitive crops downstream and has ordered the LACSD to lower chloride levels in treated wastewater.
Desalitech's Closed Circuit Desalination solution is capable of achieving high recovery with reverse-osmosis (RO) from challenging water compositions. High recovery will effectively reduce effluent discharge and brine disposal costs, which can represent over 50% of total water treatment project costs.
The pilot study will be completed at the Whittier Narrows Water Reclamation Plant (WRP) to model data for the Valencia facility 100 miles (160 km) north of Los Angeles. The Desalitech system will process 15 GPM (0.95 L/s) of municipal wastewater effluent as part of the districts' research efforts to evaluate technologies to reduce chlorides in discharges from treatment plants in the Santa Clarita Valley.
The pilot study will be conducted for 2,000 hours at 85‑93% recoveries, while monitoring average specific energy, permeate quality and scaling potential. Successful testing could lead to implementation of a full‑scale system at the Valencia WRP, which produces 22 MGD of municipal effluent.
"One of the main challenges of operating typical RO systems at the WRPs is the amount of waste they generate," said Phil Ackman, supervising engineer wastewater research for LACSD. "Disposal of this waste from inland locations can be complicated and expensive, and Desalitech's solution has the flexibility and reliability to help us meet our objectives. The potential of the Desalitech process to increase recovery and reduce waste could save the districts a tremendous amount of resources."