微生物燃料电池用于低品位锰矿浸提的研究

为提高低品位锰矿的利用,实现有机废水对锰矿物粉的浸提,通过改造微生物燃料电池(MFC),在阴极反应池中增加电解室及矿物质室,构建用于锰矿湿法浸提的MFC反应器,实现有机废水与锰矿物粉的还原氧化反应的分离。结果显示,以乙酸钠为碳源,以低品位锰矿粉为阴极的MFC输出电压最高可达0.81 V,是以K₃Fe(CN)₆]为阴极液(0.631 V)的1.23倍。在相同条件下,矿物浸提MFC对COD的去除率可达90.9%,高于对照组(87.5%),而降解时间为3 d,显著少于对照组(5.2 d)。在降解COD能力的提升上,可实现对低品位锰矿粉中MnO₂的还原,其锰含量由原矿粉的23%降至0.98%,浸提率可达95.7%。进一步通过高通量测序对阳极端菌群结构进行分析发现,其主要菌群为地杆菌属(Geobacter),相对于对照组的85%,矿物浸提MFC中该属比例占总菌群的95%。结果表明,矿物浸提MFC可有效地将有机降解与矿物浸提耦合,避免两者直接混合反应带来的二次废水污染及浸提产物硫酸锰的净化问题,在提高MFC产电效率、处理废水的同时,实现对低品位锰矿的浸提。

Study on Microbial Fuel Cell for Low-grade Manganese Ore Leaching

In order to improve the utilization of low-grade manganese ore and realize the leaching of manganese ore powder by organic waste water,by modifying the Microbial Fuel Cell (MFC),adding electrolysis chamber and mineral chamber in the cathode reaction tank,MFC reactor for wet leaching of manganese ore was constructed to realize the separation of organic wastewater and manganese mineral powder.The results show that the maximum output voltage of MFC with sodium acetate as carbon source and low-grade manganese ore powder as cathode can reach up to 0.81 V,which is 1.23 times of that with K₃Fe(CN)₆] as cathode liquid (0.631 V).Under the same conditions,the removal rate of COD by mineral leaching MFC can reach 90.9%,which is higher than 87.5% of the control group,and the degradation time is 3 d,which is significantly less than 5.2 d of the control group.In terms of the improvement of COD degradation ability,the reduction of MnO₂ in low grade manganese ore powder can be realized.The manganese content decreases from 23% of raw ore powder to 0.98%,and the leaching rate can reach 95.7%.Further high-throughput sequencing was used to analyze the structure of positive flora,which was mainly Geobacter.Compared with 85% of the control group,the proportion of Geobacter in ore leaching MFC accounted for 95%.The results show that the ore leaching MFC can effectively couple the organic degradation and ore leaching,avoid the secondary wastewater pollution caused by the direct mixed reaction of the two and the purification of the leaching product manganese sulfate.The leaching of low-grade manganese ore is realized while improving the power generation efficiency of MFC and treating wastewater.