Study on the Response of Chemical Kinetics of Fragmented Coal Under Dynamic Load

As coal resources deplete and deep mining in high-stress environments becomes more challenging, ensuring safety and sustainability in coal production is a growing concern. This study investigates the dynamic of external load on the oxidation kinetics of coal in goaf, focusing on the resulting physical and chemical changes. Thermogravimetric (TG), differential thermogravimetric (DTG), and differential scanning calorimetry (DSC) tests were conducted on long-flame coal samples under varying hammer-drop heights. Impact-loaded coal shows a shorter reaction time, higher peak intensity, and lower apparent activation energy than untreated coal. These effects intensify with increasing drop height, resulting in a 13–40% reduction in apparent activation energy. A six-step reaction pathway for pyrolysis and oxidation was developed, and kinetics parameters were determined using genetic algorithms (GA). GA-based inverse modeling produced a comprehensive reaction model for coal oxidation under dynamic load. This work presents a detailed kinetic model for coal oxidation under impact, contributing to better understanding the challenges of safety and sustainability in deep coal mining.