AWWA MTC57554

This paper focuses on the iron removal characteristics of nanofiltration (NF) membranes evaluated in Ft. Lauderdale and Hallandale Beach, Florida. Both 2 stage and single element test skids were used in the evaluation of 6 different membranes on the Biscayne Aquifer with a primary iron goal of less than 0.15 mg/L in the permeate water. The raw water for this study contained a maximum Dissolved Oxygen (DO) level of 2.2 mg/L which resulted in a partial conversion of the 1.5 mg/L ferrous ion to ferrous hydroxide. While separate oxidation and filtration was a viable alternative, pH adjustment was deemed to be the easiest solution. Includes table, figures.