Theoretical Analysis of the Heat and Mass Transfer Coupling Impacting on the Low-temperature Oxidation of Loose Coal

Considering the cross-coupling effect of the heat and mass transfer on the temperature and concentration field in the low-temperature oxidation of porous loose coal,mathematical models of oxygen pervasion and reaction,heat transfer were set up and dimensionless convection-dispersion-reaction equation was also established in the process of loose coal low temperature oxidation.The dimensionless diffusion-append heat effect similarity laws D_CT and heat-append diffusion effect similarity laws S_TC were obtained.The D_CT and S_TC have advantages to accelerate heat transfer and mass diffusion based on the numerical simulation.Important results were obtained that the concentration gradient is the main power of the heat transfer at the initial oxidation stage and the heat effect is the main power of gas mass pervasion during the stabilized oxidation stage.