Research For Treatment Of Acid Mine Drainage Diluted By Municipal Sewage With Sulfate-reducing Bacteria

Acid mine drainage is produced mining, ore processing and tailings pilling.,etc.The type of wastewater which is characterized by low pH, high sulfate concentrationand heavy metal concentration is one of the major factors of polluting theenvironment and affectting human health. If directly discharged into the environment,the impact on the environment, human, animal and plant caused great harm. There area lot of technologies to deal with this type of wastewater. Among wastewatertreatment technologies, Sulfate-reducing method by SRB has become focus ofresearch at home and abroad, because of the following advantages, such as treatingmuch more substances, having stable and thorough treatment process, and having nosecondary pollution, etc. This method is studied in-depth. The key factors of treatmentfor acid mine drainage with SRB are a affordable carbon source and the pH ofwastewater. The two factors are the limiting factors for industrialized treatment ofacid mine wastewater with SRB.The research object of this paper is the simulated acid mine drainage of JilinIWC Gold Corp. gold smelter and use municipal waste water as diluenter. Theresearch of this paper is treatment of acid mine drainage diluted by municipal sewagewith sulfate-reducing bacteria.(1)For the issue, the water samples of municipal sewage is collected atdifferent temperatures, the experiment is the change of the water samples withinseven days which include metal ions, acidity, alkalinity, chemical oxygen demand,redox potential, volatile fatty acids, ammonia nitrogen, total nitrogen, total pHosphorus and sulfate, etc. The results showed that the concentration of inorganic ionsof municipal wastewater unchanged and other ingredients changed little. So when thetime, temperature and other problems change, the municipal wastewater which usedas diluter can not affect the growth and activity of SRB.(2)This paper studied the relationship between dilution, the wastewatercomposition and pH changes when use municipal wastewater to dilute acid mine drainage. The results showed that municipal waste water can effectively raise the pHof acidic water for its acidity buffer capacity. However, the hydrolysis acidity ofdifferent metal ions is different. The solution which contains some one metal ion isdiluted by the same factor, the pH varies different. In short, the dilution factor of10orso, the pH value of the waste water can be diluted to6.0within factor of10which canbe achieved by SRB for treating wastewater.(3)The research explored the activity of SRB with different carbon sources. Theresults showed that municipal waste may provide part of the carbon source for growthof SRB. The activity of SRB can increase when added other auxiliary carbon sources,such as soybean meal.(4)Based on these experiments, with soybean meal as a secondary source ofcarbon, this paper studied the treatment of acid mine drainage diluted municipalwastewater with SRB by changing the water’s pH, sulfate concentration and the ratioof carbon and sulfur. The results showed that the components of treatment systemshave different changed. The effluent pH value reached6.71when the influent pH is4.5. The sulfate removal rate was82.6%when influent sulfate concentration is1200mg/L. And the removal rate of metal ions were higher. The best C/S wasdetermined2.0.The experimental results showd, municipal wastewater can adjust the acidity ofthe wastewater and provide some carbon source for growth of SRB when manage acidmine drainage by SRB. That makes it be possible to treatment acid mine drainageindustrializated with SRB.