Experimental air/particle flow characteristics of an 80,000 Nm³/h fly ash entrained-flow gasifier with different multi-burner arrangements

A novel burner arrangement for entrained-flow pulverized coal gasifier with multiple low-set burners, which burners are arranged to be counter-biased, is proposed aimed at mitigating high-temperature corrosion to the wall. To verify the characteristics of this improvement in an 80,000 Nm³/h fly ash entrained-flow gasifier, experiments were conducted on the model to investigate the impact of six burners being co-biased, opposed and counter-biased on the air/particle flow field by using a particle dynamics anemometer. The results show that, on the horizontal cross-section passing through burner centerlines with co-biased burners, opposed burners and counter-biased burners, the radius of mixing zone is 0.196, 0.16 and 0.174; the ratio of total particle volume flux in the near-wall region to the total particle volume flux in the measurement zone was 76.5%, 26.1% and 57.8%, respectively. On the vertical cross-section above burner outlet, the radius of central recirculation zone with co-biased burners remains to expand to 0.88 while that of counter-biased burners gradually shrinks to 0.33. There is no central recirculation zone under opposed burners; air and particle swirl numbers are close to zero. This study shows that new burner arrangement could ease high-temperature corrosion to gasifier wall and strengthens mixing of burner jets.