Explosion mechanism of electrostatic discharge in coal pulverized process
Abstract：Based on the theory of water ionization and powder dynamics, theoretical model of electrostatic fields was suggested in coal pulverized process, and numerical calculation was carried out. In order to analyze the possibility of explosion, explosion conditions were calculated. The numerical calculation results show that distribution of pulverized coal density changes with time;at the different moment, most of voltage difference between two nodal points is below 200 V, but some voltage difference can reach thousand volts, even reach ten thousand volt. The higher voltage differ- ence may reach the critical value of the breakdown voltage, and causes the electric spark. In coal pulverized process, coal-dust size distribution is between 30 and 75 μm, coal-dust concentration is between 0.5 and 2. 4 kg/m3, at some moment, oxygen percent and the effective ignition energy are more than 15% and 1 J respectively,which are all in the range of coal-dust explosion. When all of the influence factors satisfy the coal-dust explosion conditions at the same time, the explosion may occur.
Keywords：coal pulverizedelectroatatic fieldelectric sparkthe minimal ignition energyexplosion
Publication Date：2012-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 1337-1341 )