湿法炼锌沉铁过程氧化速率优化控制

湿法炼锌沉铁过程针铁矿沉淀形成的条件要求苛刻, 亚铁离子的氧化速率必须控制在合理的范围内才能保证溶液中的铁离子以针铁矿形式除去. 本文在沉铁过程动态模型的基础上, 根据针铁矿沉淀形成的条件和结合流程工艺要求, 优化设定每个反应器出口的亚铁离子浓度, 进而建立针铁矿法沉铁过程氧化速率优化控制模型. 采用控制参数化方法将最优控制求解问题转化为非线性规划, 通过状态转移优化算法求取最优的氧气和氧化锌控制率, 以合理控制沉铁过程亚铁离子的氧化速率. 仿真结果表明, 优化控制模型计算所得的控制量不仅可以保证反应过程的氧化速率符合生成针铁矿沉淀的条件, 而且可以稳定生产流程.

Optimal Control of Oxidizing Rate for Iron Precipitation Process in Zinc Hydrometallurgy

In the iron removal process in zinc hydrometallurgy, the reaction conditions to form goethite precipitate are difficult to achieve, in which the oxidizing rate of ferrous ion has to be strictly controlled to remove the iron ion from leach solution by goethite. On the basis of dynamic model for iron removal process and according to the forming conditions of goethite precipitate and procedure requirements, the optimal setting model of reactor outlet ferrous ion concentration is investigated in this paper. An optimal control model of oxidizing rate for iron precipitation process is established. The optimal control problem is transformed to a nonlinear mathematical programming problem by control parameterization method. The mathematical programming problem is then solved utilizing state transition optimization algorithm to obtain the optimal control of oxygen and zinc oxide to make the oxidizing rate in the best conditions of forming goethite precipitate. Numerical simulations validate that the optimal control of oxidizing rate can not only satisfy the forming conditions of goethite precipitate but also stabilize the production process.