RO CONCENTRATE RECOVERY IN THE EASTERN US: RESULTS FROM BENCH AND PILOT TESTING

摘要

Several public water utilities in South Florida have turned to brackish water desalination with reverse osmosis (RO) in response to increasing demand for potable water and maximization of traditional fresh sources of water. The associated challenges with concentrate disposal can limit the use of alternative water sources in inland and coastal communities. For coastal communities,saltwater intrusion during droughts and the new ocean outfall legislation in Florida could severely impact the use of brackish sources of water. Currently, the desalination capacity in the South Florida Water Management District (SFWMD or District) is 206 mgd with a projected capacity of 540 mgd by 2025 (Akpoji, 2008). Increasing recovery efficiencies from the current average of 75 percent to about 95 percent will make over 100 mgd of water available for use through more effective concentrate management. Scale forming compounds in the membrane concentrate must be removed before additional product water may be recovered.