Microbial Leaching Wenshan Low-grade, High-iron Sphalerite Pilot Study

Bio-leaching ores has the advantage of high leaching rate, low cost and little environmental pollution. It is very important for us to utilize low-grade ores in our country. The biggest shortcoming of bio-leaching is its low leaching velocity and long period, which hinders the practice of bio-leaching technology. Improving the quality of bacteria is the key factor to resolve this problem.In this paper, on the basis of the investigation of the property of the bacterium T. f, which was pretreated by acid, high temperature, metal ions, ferrosphalerite and microwave. The ferrosphalerite ore was leached by rude bacteria, domesticated bacteria and induced bacteria. The experimental results are satisfactory. This makes a good foundation for further study of bacteria leaching ferrosphalerite ores.The experimental results show that domesticated bacteria could improve leaching velocity and leaching rate which was as 30 times leaching rate as that of rude bacteria. After the ore was leached 15 days by domesticated bacteria, the leaching rate was about 30%. The leaching results of using induced bacteria were better than that of using rude bacteria and domesticated bacteria. After the ore wasleached 15 days, the leaching rate of using induced bacteria was higher 2.55% than that of using domesticated bacteria. After the ore was leached 3 day at the same pH condition(pH=2.2), the leaching rate of using domesticated bacteria was as 3 times as that of no bacteria. When pH was below 0.8, the leaching rate was lower than that of using domesticated bacteria (pH=2.2). Adding Cu2+ to leaching solution, the leaching rate was higher than that of no Cu2+ addition in the leaching solution.