Sulfate-reducing bioreactors: Efficiency of three carbon sources and removal of arsenic and selenium from mine water.

摘要

The efficiency of three carbon sources (ethanol, ethylene glycol, and acetate) for sulfate-reducing bioreactors (SRB) was investigated in laboratory column studies. Ethanol was demonstrated to give the highest efficiency and most rapid acclimation. Ethylene glycol acclimated more slowly than ethanol, but still could be a useful SRB carbon source. Acetate acclimated very slowly and also buffered the system at a pH lower than that is optimal for SRB systems.; A lab-scale SRB column study was used to investigate removal of arsenic and selenium in a neutral to alkaline wastewater. Selenium was effectively removed as insoluble elemental selenium to below the MCL (50 mug/L). With the addition of ferrous chloride in the influent, arsenic was also effectively removed to near the MCL (10 mug/L).; Undissociated hydrogen sulfide was found to limit SRB activity in the range of 20∼40 mg/L and will need to be considered for SRB treatment system designs.