Biological Removal of Selenium from Mining Influenced Waters: A Critical Review of Challenges
Nkansah-Boadu, Frank; Baldwin, Susan
University of British Columbia, Canada
Biological treatment of selenium (Se) contaminated mining-influenced water (MIW) has gained popularity in recent years. Some commonly used bioreactor configurations include; constructed wetlands, fluidized-bed bioreactors (FBR), packed-bed bioreactors (PBR), hydrogen-based membrane biofilm reactors (H2-MBfR) and upflow anaerobic sludge blanket bioreactors (UASB). The successful operation of these bioreactors is dependent on seeding with mixed microbial consortium capable of removing selenium oxyanions without interference from competing co-contaminants. This review found that these bioreactors achieved widely varying selenium removal extents ranging from 59% – 99%. However, many of these technologies were studied under pilot and laboratory-scale conditions, with only a few implemented at full-scale operations.