Treatment of Acid Mine Drainage in a Uranium Deposit by Means of a Passive System
Acid drainage waters generated in the uranium deposit Curilo,Bulgaria,were treated by means of a pilot-scale passive system consisting of a permeable reactive multibarrier and a constructed wetland connected in a series.The multibarrier had a total volume of 23 m3 and consisted of an alkalizing limestone drain and an anoxic section for microbial dissimilatory sulphate reduction,biosorption and additional chemical neutralization.The waters had a pH in the range of about 2.5～4.0 and contained radionuclides (uranium,radium),heavy metals (copper,zinc,cadmium,lead,nickel,cobalt,iron,manganese),arsenic and sulphates in concentrations usually much higher than the relevant permissible levels for waters intended for use in agriculture and/or industry.The water flow rate through the multibarrier varied in the range of about 1～17 m3/24 h,reflecting water residence times of about 300～18 hours.An efficient removal of pollutants was achieved by the multibarrier during different climatic seasons,even during cold winter days at external air and water temperatures close to 0℃.The multibarrier effluents were enriched in dissolved organic compounds and in some cases still contained manganese and iron in concentrations higher than the relevant permissible levels.These pollutants were removed in the constructed wetland as a result of the activity of different heterotrophic microorganisms,including some bacteria able to oxidize the bivalent manganese and iron ions to Mn4+ and Fe3+,respectively.
Acid mine drainage Passive systems Multibarrier Radionuclides Non-ferrous metals
S.Groudev I.Spasova M.Nicolova P.Georgiev A.Angelov
Department of Engineering Geoecology,University of Mining and Geology Saint Ivan Rilski,Sofia,Bulgaria
国际会议
XXIV International Mineral Processing Congress(第24届国际矿物加工大会)
北京
英文
3854-3860
2008-09-24（万方平台首次上网日期，不代表论文的发表时间）