Past, present and future for treating selenium-impacted water

摘要

Water quality in selected regions of the US is impaired due to selenium, which typically originates from shale formations that were deposited in a marine environment. In many respects, the geochemical behavior of selenium is similar to sulfur; they both share a common group in the periodic table of elements. Early research work in sulfate reducing bioreactors revealed that selenium was reduced biologically in concert with sulfate. The paper discusses various past, present and future approaches for the treatment of dissolved selenium in either neutral runoff from agricultural lands or neutral to acidic Mining Influenced Water (MIW) from both coal and metal mining. Both active and passive treatment technologies are considered. Selenium biochemical reactor design principles are similar to those developed for sulfate reducing bioreactors commonly used for the treatment of high concentration metal-laden acidic MIW.