Experimental and numerical study on enhanced combustion of low-rank coal: a combined approach of inclined rotation and laser assistance

To address the incomplete combustion of low-rank coal under atmospheric pressure in small-scale systems, this study proposes an enhanced burnout method that combines inclined rotation and laser assistance. By integrating EDEM numerical simulation with experimental investigation, it was identified that incomplete combustion of bottom-layer pulverized coal constitutes the main bottleneck. Results showed that optimizing the rotation initiation timing and inclination angle significantly enhances disturbance and combustion efficiency. Compared to stacked combustion, this method can reduce the unburned rate from 11.44% to 5.95%. Further introduction of laser assistance during the burnout stage lowers the unburned rate to 3.60%. Tests on multiple types of low-rank, difficult-to-burn coal confirm the effectiveness of this method, which achieves a reduction of over 50% in the unburned rate compared to stacked combustion, consistently maintaining it below 6%. This work develops a novel technical approach for advancing miniature measurement devices through optimized pulverized coal combustion.