AWWA MTC61164

The overall goal of this research was to evaluate the feasibility, efficiency, and limitations of using pressure driven membrane processes, reverse osmosis (RO) or nanofiltration (NF), to reduce total dissolved solids (TDS) loading from the Truckee Meadows Water Reclamation Facility (TMWRF) into the Truckee River. Specifically, this study focused on three primary objectives: to select the most appropriate commercially available RO and NF membranes to efficiently remove TDS from TMWRF's effluent water; to evaluate the performance, including TDS rejection, production rate, and fouling rate of NF membranes compared to RO membranes in treating reclaimed wastewater under varying operating conditions; and, to determine if additional pretreatment (pretreatment in addition to the existing dual media filtration used in the treatment plant) is necessary and to evaluate appropriate pretreatment options. The research was divided into three sections of testing. Stirred cell tests were used to obtain short-term performance data for ten commercially available membranes. Bench-scale tests were used to obtain longer-term flux and rejection data. Pilot-scale tests were used to obtain data on water flux and rejection on a larger scale and in a continuous flow setup. The feed water used for all runs was taken from a location directly after the dechlorination basin at TMWRF. For stirred cell and bench-scale runs, samples were collected as needed because of concern that biological growth would occur if one large sample was collected. Pilot-scale runs were setup at TMWRF so a continuous flow of dechlorinated water was used. Includes 9 references, table, figures.