Dynamic parameters of low temperature oxidation of weakly viscous coal at different gas concentration conditions

Abstract

In order to study the characteristics of low-temperature oxidation of weakly viscous coal under different gas concentration conditions inside the mining area and the change law of kinetic parameters, this paper adopts the coal spontaneous combustion temperature programming experimental system to test and analyze the change law of gaseous products with temperature during the low-temperature oxidation of weakly viscous coal under different gas concentration conditions, and calculate the limit parameters and activation energy during the low-temperature oxidation of weakly viscous coal. The results show that: CO gas can be used as the main predictor gas for spontaneous combustion prevention and control of weakly viscous coal, and C2H4 gas and R2 can be used as auxiliary indicators for predicting the degree of spontaneous combustion of weakly viscous coal; the maximum limit parameters of methane samples with different gas concentration conditions are distributed in the temperature range of 60-85 ℃, which is similar to the critical temperature of spontaneous combustion of coal. With the methane volume fraction increasing from 0 to 4%, the apparent activation energy of weak sticky coal shows a gradual increasing trend, increasing by 35.061, 18.426 and 25.837 kJ/mol, respectively.

Keywords

• coal spontaneous combustion
• gas concentration
• temperature programming
• low temperature oxidation
• activation energy