Effect of Immersion Temperature on Reburning Characteristics of Coal with Different Preoxidation Degrees

In light of the phenomenon where water immersion and high ground temperatures impact coal oxidation, this study conducted temperature-programmed heating and FTIR experiments to investigate the effect of water immersion temperature on the reignition characteristics of coal with varying preoxidation levels. The results show that the overall oxygen consumption capacity of coal reburning is strong with the increase in water immersion temperature at 180°C and 230°C. When the water immersion temperature is 50°C, the -CH3/-CH2- value of coal is higher than that of water immersion at 30°C and 40°C, and the maximum difference in aliphatic hydrocarbon ratio before and after reburning is 1.64%. When the temperature of pre-oxidation and immersion is 180°C and 50°C, respectively, the hydroxyl content decreases by 17.73% before and after reburning. The carbonyl content in coal after reburning exhibits varying decreasing trends under different treatment conditions. When immersed in water at 40°C, the carbonyl content in coal decreases more rapidly before and after reburning.