AWWA ACE70793

This paper discusses a 13-month pilot test of four different filtration systems to determine theoptimum pretreatment approach to minimize fouling on seawater desalination reverse osmosis (RO)membranes. Of the nine major project investigations that were done, this paper focuses on a comparison of pretreatment alternatives that include: slow sand filters;conventional treatment - coagulation andclarification + granular media filters;immersed ultrafiltration (UF) membranes;pressure UF membranes;UF operated with and without coagulation andclarification; and,each pretreatment system is followed by aseparate RO train. Background on a red tide simulation event is presented, along with results of pretreatment testing, and RO fouling trends. Study conclusions indicate that: both biological filtration and ultrafiltration canprovide successful pretreatment for seawater ROdesalination;granular media filters require more carefuloptimization than UF or slow sand filters;effective removal of algal cells upstream ofgranular media filters or UF will reducebiofouling; and,slow sand filters are simple and effective, butrequire a 50% larger footprint. Includes tables, figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2009

Number of Pages:

44

File Size:

1 file , 2.1 MB