Effects of pressure, flame type and coal feed rate on fuel-nitrogen release and nitrogen pollutant formation were examined in a laboratory scale, entrained-coal gasifier. A Utah, high-volatile bituminous coal was used. With a water-quenched probe, gas-particulate samples were collected for oxygen+oal mass ratios from 0.6 to 1.1, pressures of 1,4.9 and 10.4 atm and coal feed rates of 25 and 3.5 kg h-' . Two injector types were utilized;
one produced a diffusion flame, the other a premixed flame. Fuel-nitrogen release from the coal showed little dependence on oxygen<oal ratio, pressure or coal feed rate. Values at the gasifier exit averaged 83 74 for the diffusion flame and 92"/, for the premixed flame. Fuel-nitrogen release, mostly during devolatilization, exceeded fuel-carbon release by z 10 "4 for the premixed flame and -30% for the diffusion flame, depending on oxygen+oal mass ratio. Over 50% of the released fuel-nitrogen formed N,, with significant amounts of NH, and HCN, and smaller amounts of NO. Increased pressure at constant mass feed rates caused sharp decreases in effluent NO concentrations (to near zero) for both flame types which was explained by a combination of increased residence time and increased homogeneous NO decay rate. Elevated pressure also increased the effluent NH, and decreased HCN concentrations for the diffusion flame whereas the more complete mixing of the premixed flame resulted in lower NH, and HCN levels, and higher N, levels. In general, nitrogen species concentrations were not largely affected by coal feed rate, though increased coal feed rate decreased NH, levels somewhat.