The Effect of Thiobacillus ferrooxidans on the Distribution of Metal Trace Elements of Acid Mine Drainage Resulting in Environmental Pollution
Lu Jian-Jun~1, Lu Xian-Cai~1, Zhu Chang-Jian~1, Sun Dong-Ping~2, Gao Jian-Feng~1, Wang Ru-Cheng~1 Research, Nanjing University, Nanjing, 210093,China; 2.Graduate School, Nanjing University of Science and Technology, Nanjing, 210094,China)
Acid mine drainage (AMD) is produced by interaction between sulfide ores, water, oxygen in air and bacterium in supergene environment and is a very important cause of serious environmental pollution. Tongling district is one of the clusters of mineralization typical of polymetal deposits in the middle to lower reach of Yangtze River. Large number of waste ores have been produced during long-term mining. Oxidation of the sulfide-bearing waste ores generated AMD harmful to ecological environment. Distribution of trace elements and Tiobacillus ferrooxidans in acid mine drainage and relationship between them in Jiguanshan ore district are investigated in this paper. The studies show that the formation of AMD is related to and promoted by Thiobacillus ferrooxidans, which is identified in AMD samples. Generally, the pH values of AMD range from 2.5 to 4.2 are suitable for growth of Thiobacillus ferrooxidans. The concentrations of trace elements are the lowest in AMD with pH value around 3.0, which is most suitable for growth of Thiobacillus ferrooxidans, implicating that distribution of trace elements are controlled by Thiobacillus ferrooxidans and pH values of AMD. Trace elements, especially heavy metal elements are enriched highly in AMD and their concentrations are thousand to ten million times higher than those dissolved in a river.