Reverse Osmosis Water Treatment Plants, Hyde County and Ocracoke Island, North Carolina
Rivers designed one of the first reverse osmosis (R/O) water treatment plants for local governments in North Carolina. Rivers has designed three R/O plants including the Hyde County Ponzer and Fairfield Plants and the Ocracoke Sanitary District R/O plant.
Hyde County Plants:
Two 400 GPM production wells alternate to produce water for treatment by two 150 GPM reverse osmosis modules, with 100 GPM of reject concentrate. The water passes through 5 micron cartridge filters to the high pressure R/O feed pump. Acid and an antiscalant are added before the water passes to the R/O membrane. The water is treated when it passes through the R/O membrane under pressure, leaving a concentration behind. The concentrate stream is piped to a nearby ditch and regulated by an NPDES permit. Caustic is fed into the treated water for pH adjustment. The treated water then passes through a forced draft aerator for hydrogen sulfide removal. The finished water is stored in a 400,000 gallon detention tank, from which it is pumped to the distribution system. The project included distribution piping, an elevated tank, three booster pump stations and a telemetry system.