Study on the Heat Release Behaviors During Oxidation of Pulverized Coal-Dispersed Ventilation Air Methane in Regenerator Channels

As a low-grade energy source, ventilation air methane (VAM) can be utilized via regenerative oxidation technology. However, its low methane concentration hinders self-sustained operation in regenerators. Blending pulverized coal provides a feasible approach to supplement heat input and offers a potential route for improving energy utilization and reducing methane emissions from coal mines. This study numerically investigated the heat release behaviors during the oxidation of pulverized coal-dispersed VAM in a 400 mm-long millimeter-scale regenerator channel, with particular attention to the complementary heat-release roles of methane and pulverized coal. The results show that when the wall temperature for methane oxidation increases from 1173 K to 1373 K, the methane oxidation rate rises from 3.72 mol·m−3·s−1 to 23.87 mol·m−3·s−1—an enhancement by a factor of 5.3. For pulverized coal, inlet velocity and coal feed rate governed the completeness of pulverized coal combustion and the volatile reaction rate, respectively. Among the four tested coal–methane heat input ratios (4:1, 3:2, 2:3, 1:4), the 4:1 case showed the most favorable burnout behavior. Further analysis of a representative 2:3 co-combustion case revealed a complementary heat-release pattern: methane provided rapid upstream heat release, whereas pulverized coal sustained the downstream high-temperature region and mitigated the temperature decay after methane consumption.