Study on mechanism of pulverized coal discharge based on flow-state physical simulation

In order to study the impact of maceral component on pulverized coal output during the coalbed methane producing process,the physical simulation experim ents of the pulverized coal output with the single-phase flow displacement were conducted.The dynamic output rules of pulverized coal under the different maceral compon ents conditions in coal samples were analyzed by changing displacing flow velocity and the size of confining pressure of the single-phase flow. The experimental results sh owed that pulverized coal output had an increasing tendency with the increasing of flow velocity and confining pressure. The higher was clay content,the larger was pulveri zed coal output,and the pulverized coal output was more affected by the changes of displacing flow velocity.The higher was vitrinite content,the less was pulverized coal ou tput with the increasing of the confining pressure, and the greater impact it had with the changes of confining pressure on pulverized coal output.Moreover,in the stable conf ining pressure condition,coal permeability had an increasing tendency with the increasing of displacement flow velocity. The permeability of different coal samples became close with the increasing of the flow velocity. Furthermore,it was found in this study that the clay minerals in coal coud affect the changes of permeability significantly. The h igher was the clay minerals content,the faster was the upgrading rate of the penetration. In the stable flow velocity condition,the permeability of the maceral had a decreasi ng tendency with the confining pressure increases. Meanwhile,low clay mineral content coud not aggregate dispersed coal particles effectively.t showed that permeability C ontinued to decrease.