Cohesive Force Determination and Flowability Evaluation of Pulverized Coal in Industrial Gasification Unit

In the process of pressurized entrained-flow pulverized coal gasification,pulverized coals often form arching-bridge phenomenon in the lock hopper feeding unit due to the small particle size,the large specific surface area,and the resulting cohesive force among particles.In this paper,by using the industrial demonstration unit of SE (Sinopec-ECUST)-Gasifier pulverized coal gasification as the background,pulverized coal samples with different particle sizes as the research materials,and a combination of a continuum medium approach and a model of particle-particle interaction as the analytical method, a model to predict the cohesive force was built.By comparing the flow properties,the interparticle force as well as its relationship with the gravity of different samples,the effects of mean particle size and fine particle content on the flowability and the discharge process of pulverized coal were revealed.The results predicted by the model were also verified by the visualization platform in the lab and the industrial unit. The research results indicate,as the mean particle size decreases and the fine particle content increases,the flowability of pulverized coal becomes weaker and there is a transition from arching-bridge to arching-free flow during the discharge.The research work can provide a useful reference for improving the flowability of feeding pulverized coal and enhancing the stability of pulverized coal feeding system.