细煤泥离心过滤脱水过程的颗粒截留机理

Particle recovery mechanisms of fine coal centrifugal filtering

对小型煤泥离心过滤机及工业离心过滤机的入料、各产品的粒度分布进行了实验分析,对细煤泥离心过滤脱水过程中的颗粒截留效应进行了探讨,提出了该过程中颗粒截留的2种不同机理,即基于固有介质的截留和基于次生介质的截留.研究表明,固有介质截留主要影响和决定滤液中流失的颗粒粒度上限,而次生介质主要决定脱水产品中可回收的颗粒粒度下限.次生介质截留是煤泥离心过滤脱水过程细粒截留的主要方式,颗粒床层的结构是决定次生介质截留效果的关键,在设备开发、运行控制时应创造条件予以利用和强化.

Based on analyzing the size distribution of the scroll filtering centrifuge＇ s feed and products, the characteristics of particle capturing in the fine coal centrifugation process were discussed. It＇ s shown that two different mechanisms work together to capture the particles from losing into the filtrate, namely the screening effect of the sieve drum, and the particle-bed capturing effect caused by the structure of the settled particle bed. The former effect determines the maximum size of the particles losing into the filtrate, while the later determines the minimum size of particles can be recovered. To improve the recovery of fine particles in fine coal centrifugation, the later effect should be paid more attention while filtering centrifuge designing and operating.