AWWA MTC64550

This slide presentation outlines a study on comparing the effectivenessof microfiltration (MF) vs. ultrafiltration (UF) pretreatment on nanofiltration (NF)and reverse osmosis (RO) membrane performance related towater quality, fouling rates, andvirus rejection. The study also autopsied high-pressure membranesto evaluate foulant accumulation, and developed bench-scale teststo measure the effect of operatingconditions on long-term fouling related tobackwash, FeCl₃ dose, andfoulant accumulation. Experimental methods included:MF/RO and UF/RO operated in parallel; monitored flows and pressures;periodic measurement of water quality (WQ) parameters;simultaneous bench-scale testing;virus challenge studies; and,membrane autopsy at end of study. A program at the North Buffalo WRF inGreensboro, North Carolina is outlined. Conclusions drawn included: less RO fouling by UF than MFpretreatment;extent of RO fouling is still significant;polysaccharides implicated as foulant,though little difference in dissolved organic carbon (DOC) rejectionbetween UF and MF;colloidal removal by FeCl₃ in UFnot understood; 4-5 log removal of virus by RO, but virusfound in some permeates;virus removal increases with foulingof MF and UF;membrane permeate quality suitablefor many reuse applications; and,additional work necessary to evaluateengineering significance of results. Includes tables, figures.

Product Details

Edition:

Vol. - No.

Published:

03/01/2007

Number of Pages:

54

File Size:

1 file , 1 MB