氧化亚铁硫杆菌浸出某低品位磷矿的试验研究

Experimental Study on Leaching of a Low-grade Phosphate Ore with Thiobacillus Ferrooxidans

采用氧化亚铁硫杆菌浸出低品位磷矿,探究氧化亚铁硫杆菌的最优生长条件,并通过逐级转移驯化得到能耐受高矿浆浓度的细菌,采用驯化细菌浸出磷矿,达到提高浸出率的目的。试验结果表明:以P_(2)O_(5)品位为13.17%的贵州某磷矿为研究对象,在温度为33℃、初始pH为1.6氧化亚铁硫杆菌活性较强,浓度较高为1.63×10^(8)mL^(-1)。驯化后氧化亚铁硫杆菌浸出磷矿效率为76.6%,未经驯化的氧化亚铁硫杆菌浸出磷矿效率仅为60.3%。在矿浆质量浓度为1%、3%、5%、7%、9%时,磷矿浸出率分别为56.4%、70.4%、75.2%、64%、44.7%。以黄铁矿为营养物时磷矿的浸出率为78.6%,比以硫磺为营养物时浸出率高17.1百分点。该研究提高了低品位磷矿的浸出率,缩短了磷矿浸出时间。

Thiobacillus ferrooxidans was used to leach a low-grade phosphate ore.The optimal growth conditions of Thiobacillus ferrooxidans was investigated,and the bacteria that could resistant to high slurry concentrations was obtained by step-by-step transfer of domestication.Domesticated bacteria was used to leach phosphate ore to achieve the purpose of improving the leaching rate.A phosphate mine in Guizhou with a grade of 13.17%P_(2)O_(5)was used as the research object.The results showed that the activity of Thiobacillus ferrooxidans oxide was strong under the conditions of temperature of 33℃and initial pH of 1.6,and the higher concentration was 1.63×10^(8)mL^(-1).The P_(2)O_(5)leaching rate of thiobacillus ferrooxidans after domestication was 76.6%,and the corresponding thiobacillus ferrooxidans without domestication was only 60.3%.When the mass concentration of slurry was 1%,3%,5%,7%and 9%,the leaching rates of phosphate ore were 56.4%,70.4%,75.2%,64%and 44.7%,respectively.The leaching rate of phosphate ore with pyrite as nutrient was 78.6%,which was 17.1 percentage points higher than the leaching rate with sulfur as a nutrient.The study improves the leaching rate of low-grade phosphate ore,and it shortens the phosphate leaching time.