细磨多粒级动力学试验与模拟

Kinetics test and simulation of fine grinding with multi-size feed

以陶瓷球细磨铁矿为工程背景,提出用多粒级物料进行磨矿动力学试验与参数反算的新方法。检验细磨的零阶产率特征,如符合便可用BII法探明粉碎分布函数;利用非线性规划,通过粒度分布随磨矿时间、能量输入的演化信息推算粉碎速度函数。配合磨矿功率估算,应用总量平衡模型模拟不同给矿粒度分布、工况、能量输入水平或作业时间下的磨矿效果,包括产品粒度分布、新生粒级产率、作业比能量等。结果表明:该方法能减少细磨动力学试验的难度和作业量,有助于运用模拟展现磨矿效果随作业条件的变动规律;基于上述方法,可从小型磨矿试验结果推测大型磨机的生产状况,为工艺设计与设备选型提供量化依据。

A new method was presented by which kinetics functions were readily obtained from the grinding tests with multi-size feed. Zero order characteristics of fine grinding was verified and thus breakage function could be deduced by BII method. Selection function was inferred by non-linear programming based on the particle size distribution(PSD) evolution with time or input energy. Cooperated with milling power estimation, the population balance model predicted the milling performance, such as PSD, productivity, specific energy, etc., which were affected by the PSD of feed, operating conditions and input energy. The results show that the method facilitates the study of fine grinding kinetics significantly, by which the variation of milling performance with operating conditions can be properly simulated. Moreover, the full-scale milling operation can be predicted based on small-scale tests, which will facilitate the grinding circuit design with detailed data.