Out With The Old – In With The New: Working With a Regulator to Replace 9-Year Old UF Membranes

Many older proprietary microfiltration and ultrafiltration (MF/UF) membrane systems have been in service long enough to require replacement of the membrane elements. This paper presents methods to specify and select new replacement elements for existing proprietary systems allowing competitive bids between suitable manufacturers (rather than risking higher costs due to sole-sourcing) including bid evaluation and regulatory approval if an alternative membrane product is selected, illustrated by a real-world case, the 9-year-old 12-mgd UF membrane filtration plant in Mankato, Minnesota. The information presented is intended to help membrane system owners have options and save money on membrane replacement projects.