针铁矿法沉铁过程的混杂建模与控制

摘要

A modeling and control method based on hybrid theory was proposed due to controlling the iron ion concentration and pH value difficultly in iron precipitation by goethite process. A mathematical model of iron precipitation by goethite process was built based on the physical and chemical reaction mechanism of iron precipitation and material balance principle. An effective concentration of dissolved oxygen in different interval of Fe2+concentration model was constructed by analyzing the effects of Fe2+ concentration on dissolved oxygen in solution. The switching controller of the iron precipitation system was designed based on Fe2+ concentration and effective concentration of dissolved oxygen by using common Lyapunov function technique. The simulation results show that this modeling and control method is effective to reflect the dynamic changes of ion concentrations during precipitation of iron, which meets the process indexes.%由于针铁矿法沉铁过程铁离子浓度和pH值难以控制，提出一种基于混杂系统理论沉铁过程的建模与控制方法。在深入分析沉铁过程物理化学反应机理的基础上，采用物料平衡原理，建立基于连续搅拌釜的数学模型。针对溶液中Fe2+浓度对氧气有效溶解浓度的影响，建立Fe2+浓度不同波动区间内有效溶解氧浓度切换模型。采用公共李亚普诺夫函数的方法，给出基于溶液中Fe2+浓度和有效溶解氧浓度的沉铁系统切换控制器的设计方法。仿真结果表明：混杂建模与控制方法能反映沉铁过程各离子浓度的动态变化，满足工艺指标。