Study On Stratification Change And Solid Flux Model In Coal Slurry Sedimentation

Coal slurry treatment is an important link in coal washing and processing.With the improvement of coal mining mechanization,a large number of small particles of slime are produced,which brings challenges to slime water treatment.At present,the sedimentation effect and bottom flow concentration efficiency of coal slurry are usually reflected by turbidity detection and manual detection of slime thickness.The instrument error and the influence of human factors often cannot truly reflect the sedimentation or concentration effect of coal slime water.This paper tries to reflect the sedimentation effect by studying the stratification of coal slurry sedimentation process,and provides a reference for the overflow circulation and the discharge of bottom flow.In this paper,design different high concentration slurry settlement process change test,the slime water settling velocity in the process of subsidence,concentration of local properties are studied,such as the movement state of slime water change has explored and layering is settling properties,analyzes the relationship between the local concentration and solid flux,and explores the influence the concentration of the sedimentation efficiency layer.The coal slime in this paper is taken from raw coal belt and concentrator of a coal preparation plant,and the natural sedimentation test is carried out under the conditions of coal slurry concentration of 10 g/L,20 g/L and 30 g/L.In order to explore the stratification of coal slurry in the sedimentation process,this study designed a sample concentration test,designed a method of sampling at multiple points at the same time,built a solid-liquid interface detection device,and selected the detection equipment.The coal slurry settlement test with multi-point sampling at the same time was designed.The slime water at 5 sampling points at different times was dried,weighed and its concentration was detected.Combining the sedimentation rate change rule,the five sampling points slime water movement rule was analyzed,on the same sampling point sampling concentration under the conditions of different concentrations were analyzed,and determine the different stages of settlement and their corresponding subsidence area,the results show that two kinds of coal subsidence process can be divided into free settling stage,middle and later periods of the interference,interference early subsidence and slime slow compression stage,clarify in all phases of the layer,transition layer and sedimentation and the height of compression layer are changed.Finally,a solid flux model of sedimentation process is established,and the change law of local concentration and solid flux is nonlinear fitted.By comparing the model of the actual flux and the theoretical flux curve,it is shown that there is a concentration limiting layer which restricts the sedimentation efficiency.There are 31 figures,13 tables and 78 references in this paper.