Experimental investigation of electrostatic generation of coal granules

doi:10.7523/j.issn.2095-6134.2020.02.011

Abstract

Abstract: Coal granules are widely used in gas-solid two-phase transmission industries, such as mining and energy. In the industrial process, electrostatics is generated by the collision and friction between the coal granule and between the granule and the wall surface. If it is not discharged in time, it will gradually accumulate in the working system, thereby causing many problems for the safety production, such as granule clustering, blocking, sparking, explosion, etc. In addition, the charged granules in the gas-solid two-phase flow cause a series of measurement problems, which seriously affect the measurement accuracy and even damage the instruments. The main task of this experiment is to establish a measurement experiment system for electrostatic generation of single coal granules,and to study the effects of the physical factors, sliding velocity, environmental relative humidity, surface roughness, and granular materials on the generation of electrostatics. After comparing and analyzing the data, we found that these factors have greater impacts on electrostatics, and a comparative analysis was conducted to summarize the mechanism of electrostatic generation of single granules and the influences of various factors.

Key words: coal, granules, electrostatics, surface roughness

CLC Number:

O359

FANG Jia, ZHAO Yanlin, YAO Jun, WANG Chi-Hwa. Experimental investigation of electrostatic generation of coal granules[J]. , 2020, 37(2): 220-227.

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