Pilot testing of reverse osmosis for salinity and organics control in a coastal supply source

Abstract The results of pilot testing demonstrate that RO can be used successfully on conventionally treated Northwest River water to control seasonal salinity increases and reduce disinfection by-products in the finished water to the more stringent levels anticipated under the forthcoming disinfectants/disinfection by-products (D/DBP) rule. Both cellulose acetate (CA) and thin-film composite (TFC) membranes can be operated satisfactorily on alumtreated river water. As anticipated, the CA membranes demonstrate lower levels of fouling; however, the TFC membrane provide greater organics removals. The membranes most appropriate for the future full-scale plant will be determined from a present-worth cost evaluation of CA and TFC membrane capital and operating costs.