AWWA MTC64598

This paper presents a study on the development and validation of a laboratory-scalemembrane testing protocol to select viable membranes for pilot- and full-scale operation.This selection protocol balanced operational characteristics (such as pressure, flux andpotential for fouling) with product water quality and allowed for a pre-selection ofpotentially viable candidate membranes. Membranes considered for selection werecharacterized as thin-film composite (TFC) polyamide membranes and includedcommercially available ULPRO (TFC-ULP, Koch Membrane Systems; XLE,Dow/Filmtec; TMG10, Toray America; RE-BLR, Saehan) and nanofiltration (NF) membrane products(NF-90, NF-270, NF-200 and NF-4040, Dow/Filmtec; TFC-S, Koch Membrane Systems;ESNA1-LF, Hydranautics; MX07, Osmonics; NE-90, Saehan).Three candidate membranes were selected and tested using a 68 L/min (18 gpm)membrane pilot skid that was designed, constructed and operated during this study. Thethree selected candidate membranes were each tested for at least 1,300 hours onmicrofiltered feed water at two full-scale facilities. The different feed waters representednon-nitrified microfiltered effluent provided by the West Basin Water Recycling Plant(WBWRP) in El Segundo, CA and nitrified/denitrified microfiltered effluent provided bythe Scottsdale Water Campus (SWC), Arizona. Operational performance and rejection of trace organics, nutrients and total organic carbon were monitored during pilot-scale testing andcompared to the performance of full-scale trains operating on the same feedwateremploying conventional RO membranes (i.e., TFC-HR, Koch Membrane Systems andESPA2, Hydranautics). During several occasions, challenge tests were conducted at pilot-scaleto examine rejection of trace organics during periods of elevated feedconcentrations. The best performing ULPRO membrane was also selected for testing over5,000 hours in a 6.6 m³/min (2.5-mgd) full-scale reverse osmosis (RO) train to further verify findings frompilot-scale and to determine rejection behavior and operating costs under full-scaleconditions.The study was assisted through state-of-the-art membrane characterization todescribe the fouling character of NF/ULPRO membranes and its role on operation (e.g.,flux decline) and rejection. A comprehensive membrane autopsy was performed aftereach pilot-scale testing period to determine the nature of the observed flux decline andcharacterize the type and location of fouling. Includes 12 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

03/01/2007

Number of Pages:

10

File Size:

1 file , 740 KB