(9)Remediation of acid mine drainage by microorganism

摘要

Acid mine drainage (AMD) is an environmental problem that mainly occursonce mining operations have closed. These liquids are generated by theexposure of sulfide minerals to oxygen and water present in the environment.The aim of this project is to develop a bioremediation treatment of drainsgenerated by the mine through the use of the bacteria Bacillus pasteurii. Thisprocess helps to reduce the concentration of heavy metals in AMD and alsoincreases the pH of the acidic water, allowing for the water to be recoveredand returned to productive mining processes or to the environment.The work methodology consists of obtaining a culture medium thatallows for goodmicrobial growth and enzymatic expression. We work withthree growth media at room temperature and with different nutritionalcharacteristics, analitycal grade as a reference and industrial grade to getan idea of large-scale application, allowing us to obtain a culture up to90% cheaper.Using 5% v/v of the culture medium with the microorganism andsynthetic AMD, it was possible to obtain a reduction of the Fe content by38.8%, Al 90.1%, Mn 5.3% and Mg 7.4% and increase the pH to 7.3. This iscaused by trapping the cations in the crystalline structure of calciumcarbonate and increasing the pH.