变频刚柔搅拌反应器强化锰矿浸出及除铁过程

传统锰矿浸出过程采用刚性搅拌反应器，存在矿粉悬浮效果差、锰矿利用率低、浸出液中铁含量较高的问题。本文采用变频刚柔搅拌反应器强化锰矿的浸出过程，实验对比分析了不同桨叶类型、搅拌桨操作方式和变频间隔时间对锰矿浸出效果、搅拌功耗的影响，同时分析了变频刚柔桨耦合空气射流在除铁过程的效果。结果表明，变频刚柔桨通过柔性钢丝绳对流体的扰动作用以及变频操作对稳定流场的更新作用，提高浸出液中Mn²⁺含量；同时，由于体系变频操作的频率变化，降低了搅拌功耗。相同功耗下，刚柔组合桨体系浸出液中Mn²⁺含量相对于刚性桨体系提高了10.8%；相同转速下，刚柔组合桨体系在浸出过程的功率消耗相对于刚性桨体系提升了25.4%。变频间隔时间为30min时，变频刚柔桨体系浸出液中Mn²⁺含量相对于刚柔组合桨体系降低了2.17%，但相应搅拌功耗降低了28%。调节体系pH后，采用变频刚柔桨耦合偏心空气射流操作，可有效降低浸出液中Fe²⁺含量。在通气60min后，浸出液中Fe²⁺浓度已至较低水平，低于0.15mg/L。

Manganese ore leaching and iron removal intensified by variable frequency rigid-flexible stirred reactor

Traditional rigid stirring reactor used in manganese ore leaching process has poor suspending effect of mineral powder, low manganese ore utilization and high iron content in leaching solution. The effects of impeller type, operating mode and frequency conversion interval on manganese ore leaching and power consumption were investigated experimentally, and the effect of variable frequency rigid-flexible impeller coupled with air jet in iron removal process was analyzed. The results showed that the flexible wire rope could disturb the fluid and the variable frequency operation could update the stable flow field, which increased the content of Mn²⁺ in the leaching solution. Meanwhile, due to the frequency change of the system frequency conversion operation, the power consumption was reduced. Mn²⁺ content in rigid-flexible stirred reactor increased by 10.8% than the regular stirred reactor in same power consumption. Power consumption in rigid-flexible stirred reactor increased by 25.4% than the regular stirred reactor in same stirring speed. When the frequency conversion interval was 30min, the Mn²⁺ content in variable frequency rigid-flexible stirred reactor decreased by 2.17% than the rigid-flexible stirred reactor. While the power consumption decreased by 28%. After adjusted the pH of the system, variable frequency rigid-flexible impeller coupling eccentric air jet could effectively reduce the Fe²⁺ content in the leaching solution. After 60min of aeration, the concentration of Fe²⁺ in the leached solution reached a low level, less than 0.15mg/L.