碱性浸矿细菌是处理碱性脉石矿物的新型高效菌株. 为提高碱性浸矿细菌( Providencia sp. )的浸矿适应性和浸出率,首次对其进行铜矿浆驯化和紫外诱变改良. 使用Design Expert-8软件对改良菌株进行三因素三水平Box-Behnken试验设计与结果分析,考察矿浆中固相质量浓度、接种量和温度三个因素与浸出率之间的关系,利用Design Expert-8软件对试验条件进行优化,确定改良菌株最佳浸出条件,并得到浸出率预测模型. 在最佳浸出条件下对改良菌株与原始菌株别进行浸出试验,比较二者在改良前后生长及浸出率的变化情况. 结果显示:改良菌株能更好适应矿浆环境,细菌浓度最高时可达6. 5 × 108 mL-1左右,浸出率达到了50. 57%;而改良前细菌浓度最高只有3 × 108 mL-1 ,浸出率也只有29. 03%.%Alkaline leaching bacteria are new efficient strains for processing alkaline minerals. Slurry gradient domestication and ultraviolet mutagenesis were introduced to improve the adaptive capacity to environment and leaching rate of the strains. With the help of Design Expert-8 software, a three-factor three-level Box-Behnken experiment was conducted to investigate the influence of pulp density, initial bacteria inoculation and temperature on the leaching rate. The optimal experimental condition was determined by Design Expert-8 software and a prediction model was proposed in this paper. Comparative experiment was conducted to investigate the differences before and after this improvement experiment under the optimal conditions. The results show that the improved strain can adapt to the pulp condition better. The population of the improved strain can up to 6. 5 × 108 mL-1 and the leaching rate reaches to 50. 57%, while the population of the original strain can up to 3 × 108 mL-1 and the leaching rate reaches only to 29. 03%.
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