COST ESTIMATES FOR MEMBRANE FILTRATION AND CONVENTIONAL TREATMENT

Costs of several ultrafiltration and nanofiltration processes are comp ared with the cost of conventional liquid-solid separation with and wi thout GAC adsorption for small facilities. Data on raw-water quality, permeate flux, recovery, frequency of backflushing, and chemical dosag e obtained from a pilot study were used with a previously developed mo del for membrane costs to calculate anticipated capital and operating costs for each instance. Data from the US Environmental Protection Age ncy were used to estimate conventional treatment costs. All of the mem brane process calculations showed comparable or lower total costs per unit volume treated compared with conventional treatment for small fac ilities (<200,000 m3/d or about 5 mgd).