Influence of Filter Media on the Catalytic Upgrading and Dust Removal Performance of Low-Rank Coal Pyrolysis Tar Gas

Coal pyrolysis technology is the core process for achieving the staged conversion of coal. It significantly enhances resource utilization while reducing pollutant emissions, playing a crucial role in promoting the clean and efficient utilization of coal. The coal pyrolysis process suffers from issues such as dust entrainment causing pipeline blockages and degraded tar quality. Particle beds demonstrate application potential due to their dual functions of catalytic upgrading and filtration dust removal of tar. This study investigates the regulatory effects of various materials with distinct properties on coal pyrolysis tar gas, and the dust removal performance of each material is analyzed. Compared to inert filtration media, carbon-based materials increase light oil yield and reduce pitch yield in pyrolysis tar, effectively improving tar quality. Compared with the blank control group, carbonized carbon material (BC) and activated carbon (AC) material reduced pitch yield by 0.58 wt.% and 2.61 wt.%, respectively. BC enhances tar quality while increasing tar yield by 5.57 wt.% and 4.99 wt.% compared to AC and activated carbon material (BHC), respectively. It also reduces coke yield by 1.60 wt.% and 1.04 wt.%. Furthermore, the carbon-based filter medium demonstrates outstanding removal efficiency for fly ash particles ranging from 1-25 μm and >110 μm. Its unique pore structure guides airflow and adsorbs dust, mitigating the “air cushion effect” while enhancing dust removal performance. BC achieves a dust removal efficiency of up to 96.87% at a pressure drop of only 110 Pa. Combined with its catalytic upgrading capabilities for tar gases, it holds application potential in granular beds.