THE CURRENT STATUS OF THE USE OF MEMBRANES FOR WASTEWATER TREATMENT

摘要

The Water Environment Research Foundation’s (WERF’s) Project on the use of membrane treatment of secondary effluent for subsequent use (No. 01-CTS-6) has developed both an inventory and a survey of municipal full-scale wastewater facilities using membrane technology as tertiary treatment. Over 100 facilities have been identified worldwide, with more than 50 percent concentrated in the United States (U.S.). More than 80 percent of the plants have a membrane treatment design capacity less than 5 mgd. The survey collected specific plant information (site data, concentrate disposal methods, operational/maintenance data, description/performance of membrane, and capital and operation/maintenance costs) from 11 facilities (10 in the U.S. and one in Singapore). The main findings of the survey were: 1) reverse osmosis (RO) is the membrane of choice to remove TDS and organics in more than 80 percent of the surveyed plants, 2) ocean outfall and evaporation pond/discharge to the sanitary sewer system are the preferred concentrate disposal methods for coastal and inlands plants, respectively, 3) urban irrigation and creation of a barrier against sea intrusion are the primary permeate uses for heartland and coastal facilities, respectively, and 4) capital costs of the membrane facilities average US$6.81/gpd whereas the annual operation/maintenance cost is estimated at US$1.27/Kgal.