Design And Numerical Analyses Of A Anthracite Blended Pulverized Coal Burner

Based on the reasons of the poor combustion of the anthracite,a new burner based on a normal pulverized coal burner is designed in this paper to solve the poor combustion of the anthracite,namely the New Type Bias Combustion Swirl Burner(NTBCSB),By means of numerical simulation theory analysis studies on the stable combustion performance of NTBCSB are performed in detail.The NTBCSB designs take the mixture of the primary air-pulverized coal flow and the recirculation flue gas into consideration carefully,by reasonable air distribution and special structure,to achieve desired bituminous coal combustion effect of culm.The pulverized coal from the primary flow duct can be concentrated in the boundary of the recirculation zone by the effect of the necking flaring.The air-pulverized coal flow leaving the burner rapidly moves into the recirculation zone,the pulverized coal particles don’t diffuse into the secondary air zone. Moderate intensity of spiral wind flow can promote the bituminous coal and anthracite mixed burning, and strengthen airflow disturbances.The third air with high wind speed can blow combustion furance wall effectively to help space high temperature zone and the combustion furance wall to prevent the pulverized coal’s slagging and depositing in the furance.In this paper, the NTBCSB three-dimensional numerical calculation model is established, using the provided professional computational fluid dynamics software ANSYS CFX and the flow field of burner,particle field,temperature field and concentration field in the simulation.The three dimensional shape of the recirculation zone analyzed to research the combustion stability of NTBCSB. The statement and the movement of the particals is analyzed by the partical field calculation,the mixing effect of the pulverized anthracite is analyzed by the concentration calculation.The NTBCSB with traditional swirl burner combustor ultrafine single burning bituminous coal,anthracite and bituminous coal and Micro-anthracite mixed coal combustion characteristic analysis of three kinds of conditions,the simulation results indicated that the burner has good steady performance,and effectively reduce NOx emissions.