Program Monday
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Wednesday 9:00 Song Jin, Ph.D., CHMM., Lead Scientist Western Research Institute
Author(s) Song Jin, Ph.D., CHMM.
Chemical neutralization, wetlands and other passive methods are widely used in treating acid mine drainage (AMD); however, none of these methods addresses the source of AMD, which continuously generates acid effluent and loads the treatment system with unlimited amount of acid water. Certain species of sulfate-reducing bacteria (SRB) can survive in acidic environments. The sulfate reducing metabolism consumes protons, resulting in the rise of pH and precipitation of metal sulfides. In this study, SRB consortium and substrates were amended to AMD to achieve a barrier of biofilm that coats the surface of metal sulfides, shielding oxidants from oxidizing AMD source compounds. Different sources of SRB and substrates were identified and evaluated. Microcosms containing AMD water were studied before the field applications. In the laboratory study, SRB activities were aggressive in AMD water with pH as low as 3.0. pH was raised to neutral range and stabilized for over a year upon the initial amendments of SRB and substrates. No sulfate reduction occurred in microcosms in which pH was below 3.0. By manipulating the dosage of SRB-substrate injection, biofilm formation and the metal-sulfides from the SRB metabolism can effectively consume the oxygen and mask the AMD source from being oxidized. The results from this study may offer a long-term and economical method of controlling AMD at its source. Field applications are currently undergoing at a coal mine in eastern Tennessee. Biography Dr. Song Jin is a Lead Scientist with the Western Research Institute in Laramie, Wyoming. He has a Ph.D. in Environmental Microbiology and an M.S. in Molecular Biology from the University of Wyoming. Dr. Jin’s research includes aerobic and anaerobic biodegradation of various contaminants in soils and groundwater. He is also directing studies in biological control of Acid Mine Drainage and enhancement of biogenic methane production from coal and oil shale.
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