China Nonferrous Metallurgy

Indigenous microorganisms is used for controlling pollution of U(VI) and Zn(II) in uranium tailings wastewater in situ due to their advantages of diverse species, strong adaptability and co-metabolism. The effect of the selected and domesticated indigenous microbial flora on removal of low-concentration uranium and zinc was studied. The effects of bacterial liquid dosage, temperature, pH, U(VI) and Zn(Ⅱ) initial concentration on the removal of uranium and zinc from indigenous microbial flora were investigated. The results showed that for the neutral mixed solution containing 1mg/L U(VI) and 10mg/L Zn(II), the bacterial flora of indigenous microorganisms (Acinetobacter 44.69%, Acetobacter 31.48%, Aureus spp. 13.81%) at a temperature of 35℃ and a dosage of 10% the bacterial solution, the removal effect of two heavy metal elements is the best, the removal rate of uranium and zinc can reach more than 94%, and the reaction is rapid, basically reaching balance in 60min. The characterization analysis of microorganisms showed that a certain amount of sheet-like substances appeared around the cells after the colony reacted with metal ions, and the newly emerged U peak and Zn peak accounted for 6.6% and 0.62% of the cell proportion, respectively. The study provides a certain technical support for treatment of uranium and heavy metals in uranium tailings pond wastewater.