The use of membranes as a treatment for granular media SFBW has been discussed but has yet to be applied. EE&T, Inc. has previously bench tested microfiltration (MF) membranes and pilot tested submerged hollow fiber membranes to treat SFBW (Cornwell et al., 2001). Although treatment was successful, the cost was quite high when compared to other options. In an effort to evaluate alternatives that might be more satisfactory, bench-scale testing of potentially lower cost, innovative membrane options were investigated.
There are reports in the literature of using crossflow MF and UF membranes for treating granular media SFBW in European pilot studies (Vigneswaran et al., Dotremont et al.), and in full scale operations (Brugger et al., 2001; Song et al., 2001). There is also an on-going Foundation TC Project (2568) that is specifically evaluating the use of four different manufacturers' membranes for the treatment of granular media SFBW in New York City (NY). No data is yet available and the project appears to be on a "long term hold".
There are four treatment facilities that use membranes to treat the reject from membranes used in a main filtration process: one in the US, two in the UK, and one in Canada . However, the focus of Foundation Project #3114 is innovative treatment options for granular media SFBW only.
See Chapter 4 of project report for a discussion of bench-scale evaluation of SFBW treatment with low pressure membranes (including hollow fiber, tubular, and ceramic materials) conducted at the University of Massachusetts as part of this project.