Study on Gas Explosion Law Induced by High Temperature Source in Coal and Rock Media

Research output: ThesisMaster's Thesis

Authors

Abstract

All along, the gas explosion accident still seriously threatens the production safety of coal mines. Due to the complex underground environment, the gas explosion accident often causes heavy casualties and economic losses. Based on the methane combustion and explosion theory and the turbulent acceleration mechanism, this paper uses the high-temperature source-induced gas explosion experiment system to conduct an explosion experiment on the gas-air mixture under the condition of coal-rock medium to study the change law of the gas explosion induced by the high-temperature source in coal-rock medium. In the experiment, coal block, rock block, coal dust and coal block rock block mixture were selected as the coal and rock medium conditions of the experiment. The experimental results show that the coal block covering the surface of the high temperature source can promote the gas explosion, and as the mass of the coal block covering the surface of the high temperature source increases, the intensity of the gas explosion also increases. At the same time, the coal covered on the surface of the high temperature source will decompose other combustible gases when heated, resulting in a significant change in the gas composition in the explosion container after the explosion; For the methane-coal dust-air mixture, the presence of coal dust promotes the gas explosion. In addition to being decomposed by heat, the coal dust can also decompose other combustible bodies, and also directly participate in the explosion reaction itself. In addition, the particle size of coal dust also has an effect on gas explosion. The larger the particle size of coal dust, the lower the gas explosion intensity. This is because the larger the particle size of coal dust, the lower its dispersion and the less complete the reaction. For the methane-rock-air mixture, the gas explosion intensity increases with the increase in the number of rocks and the blockage ratio, indicating that the rock block obstacles can stimulate and promote the gas explosion. For the rock media of different shapes, the cuboid has the greatest influence on the gas explosion, the sphere has the second influence on the gas explosion, and the cylinder has the least influence. For methane-coal block/rock block-air mixtures, different types of coal-rock media can promote gas explosion, but due to the different placement of the medium in the explosion vessel, the degree of impact on gas explosion is different. The influence of the medium on the gas explosion is also different. The specific performance is that under the conditions of coal block medium, the gas explosion intensity is stronger than that of rock block medium. When the coal block covers the surface of the high temperature source, the explosion intensity is stronger than that the coal block is placed around the high temperature source.

Details

Translated title of the contributionStudy on Gas Explosion Law Induced by High Temperature Source in Coal and Rock Media
Original languageEnglish
QualificationMSc
Awarding Institution
Supervisors/Advisors
Award date25 Jun 2021
Publication statusPublished - 2021