在单因素实验的基础上,研究操作过程各因素对除铁率及钴回收率的影响,并采用中心复合设计实验方法对除铁过程进行优化建模。结果表明:部分水解针铁矿法(即E.Z针铁矿法)适用于含钴生物浸出液的除铁过程,得到的数学模型与实验结果具有较高吻合度,偏差的绝对值小于1%。该模型的方差分析结果显示,在 pH 值为3.5~4.5的范围内,除铁率的主要影响因素为温度、晶种量及其交互作用,而pH值与晶种量之间的交互作用对除铁率的影响可被忽略;钴回收率的主要影响因素为 pH 值及 pH 值与晶种量之间的交互作用。该模型可用于生产中针铁矿除铁过程控制参数的优化。
The central composite design experimental method was employed to establish and optimize the model of iron removal process on the basis of the single factor experiment. Meanwhile, the influencing factors of the iron removal rate and the cobalt recovery were also discussed. The results show that, E.Z goethite method is suitable for the iron removal process from the cobaltiferous bioleaching solution, and its mathematical model is well fitted with the trial result. Their absolute deviation is less than 1%. The results of model variance analysis show that, when the pH value is in the range of 3.5?4.5. Temperature, the amount of seed crystal and the interaction between them are the main control factors for the iron removal rate. The interaction between the amount of seed crystal and pH value affects the iron removal rate weakly. It is also found that the cobalt recovery changes markedly with pH value, and the interaction between pH value and the amount of seed crystal. Besides, the model can be used to optimize the control parameters of the iron removal process.