微生物硫化浮选低品位氧化型镍矿界面作用研究

Because of the difficulty in disposing refractory low-grade nickel oxide ore, handling the ore causes not only the waste of resources, but also great harm to the environment and people's health. A new technology for the sulfuration of Jinchuan low-grade nickel oxide ore by using curing agent produced biologically with sulfate-reducing bacteria (SRB) is proposed. The two key scientific issues, interfacial interactions between SRB and the nickel oxide ore, and rule of controllable preparation of biological curing agent will be investigated. Performance and regulatory law of biological curing agent will be studied, the metabolism of different electron donors and the effect of calcium and magnesium carbonate precipitation in pH and sulfide concentration will be revealed. Immobilization technique with polyurethane foam acting as a carrier will be mastered. Furthermore, the impact of different factors on the production of the curing agent and sulfuration process will be evaluated. Mathematical absorption model of extracellular polymeric substances and mineral will be established based on Aspen adsorption software. On this basis, the appropriate operating process will be designed, and the basic data will be provided for the realization of efficient disposing refractory low-grade Jinchuan nickel oxide ore by the new hydrometallurgical process.

低品位氧化型镍矿难以通过浮选富集，一般只能堆存处理，不但造成资源的浪费，而且给环境和人们的生命健康造成巨大危害。本项目提出微生物硫酸盐还原菌还原生产硫化剂用于低品位氧化型金属矿硫化浮选的新思路。利用实验和模型分析方法，围绕硫酸盐还原菌与氧化型矿的界面作用规律和生物硫化剂可控制备方法这两个关键科学问题，研究生物硫化剂的性能和调控规律，揭示不同电子供体的代谢和钙镁碳酸盐沉淀、复溶过程对反应液pH、硫化物浓度的影响规律，掌握聚氨酯泡沫材料充当载体的微生物固定化技术；评价不同因素对硫化剂制备和硫化过程的影响规律，基于Aspen adsorption软件建立胞外聚合物与矿物吸附的数学模型，指导难处理金川低品位氧化型镍矿分离富集绿色湿法冶金工艺的工程设计和优化改造。

低品位氧化型镍矿难以通过浮选富集，一般只能堆存处理，不但造成资源的浪费，而且给环境和人们的生命健康造成巨大危害。本项目提出微生物硫酸盐还原菌还原生产硫化剂用于低品位氧化型金属矿硫化浮选的新思路。项目建设已来，围绕生物硫化剂性能调控规律、SRB-氧化型镍矿界面作用规律以及硫化条件作用影响规律三个主要研究内容开展研究。研究发现:(1)适量添加Fe3+([Fe3+]=1 g•L-1)对SRB的还原活性是有利的，硫酸根去除率较高。因为铁离子是硫酸盐还原菌酶的激活剂，可以促进酶的活性，削弱金属毒性。（2）硫化后的矿物疏水性较强，对硫化剂的吸附能力较强。随着硫化剂的用量增加，矿物对硫化剂的吸附能力也逐渐增加。（3）孔雀石矿生物硫化最适宜的条件：温度为35℃，矿物粒径为200目左右，实际菌液用量为理论值的2.5倍，硫化时间为30min效果最好。（4）氧化型镍矿的适宜生物硫化浮选条件：搅拌时间为5min，硫化剂用量为理论值的0.85倍，pH值为8.5，抑制剂水玻璃的用量为220g/t，捕收剂丁基黄药用量为150g/t。