Release of fuel-N during entrained-flow gasification of fuel mixed with model compound

Model compound pyridine was added to diesel oil to simulate the existence of coal-N. A laboratory opposed multi-burner (OMB) gasifier was used to investigate the axial and radial concentration distribution of HCN, NH3, NO and N2. The maximum concentrations of nitrogen pollutants (HCN, NH3 and NO) are produced at the nozzle plane and these concentrations decrease away from the plane. Moreover, N2 participates in gasification and the order of concentrations of nitrogen compounds in exit is N2>HCN>NH3>NO. NO and N2 increase as O2/fuel ratio increases. HCN and NH3 reach maximum when O2/fuel ratio is 1.3, but largely decrease at 1.7 and 0.9. Flow field distribution make radial concentration profiles uniform toward the exit region and low near the side-wall in other axial position. The steam addition leads to increased formation of HCN and NH3, whereas decreased formation of NO. The results may be useful for the further investigation of coal-N conversion mechanism.