Method of hydrothermal treatment for coal spontaneous combustion inhibition and its application

Abstract

The use of coal combustion inhibitors, which are mostly sprayed on the surface of the coal that remains in the mining region (post-mining inhibition), has a significant effect on preventing spontaneous burning of coal, although their duration of action is limited. Pre-inhibition (pre-mining inhibition) prolong the inhibition duration and offers the chance to change the temperature of the inhibition fluid. This results in the suggestion of a hydrothermal inhibition strategy that emphasises the influence of inhibition fluid temperature on the inhibitory effect in order to achieve accelerated inhibition. Infrared tests and temperature-programmed oxidation are used to explore the inhibition law and mechanism of inhibition temperature on the spontaneous combustion of different coal orders. The findings demonstrated that when the inhibition temperature increased to 30 °C, 40 °C, 50 °C, 60 °C and 70 °C, the average inhibition rate and cross point temperature increased dramatically while the rates of oxygen consumption, exothermic rate, and CO production continuously dropped. Simultaneously, the coal's content of more reactive groups, such methyl and methylene, dropped, and the coal's risk to self-heat reduced. At the 70 °C inhibition temperature, the lignite coal showed the maximum inhibition rate (65.28%). This research is crucial to advancing the inhibitor's application technology and efficiency of inhibition.