Investigation on slag resource utilization: KHCO3/modified slag composite powder applied to methane/air explosion suppression

Exploring the application of slag in methane explosion suppression can contribute to its waste resource utilization. In this study, waste slag was subjected to high-temperature scorching and modified using the sol-gel method. Subsequently, a mechanochemical technology was employed to create a composite powder consisting of KHCO 3 and modified slag. A 20 L explosion ball was also used to assess the features of explosion suppression, and pyrolysis characteristics and explosion products were analyzed to clarify the underlying mechanism. The best explosion suppression was shown by adding 0.1 g/L 40 wt% of KHCO 3 /modified slag composite powder. It reduced P max and (d P /d t ) max by 42.35% and 89.47%, respectively, while extending the time for the flame to reach the edge of the transparent window by a factor of 7.1 in 9.5% methane explosion. The KHCO 3 /modified slag composite powder efficiently suppresses explosions by absorbing heat, creating barriers, and adsorbing and consuming free radicals.