CATALYTIC DECOMPOSITION OF AMMONIA IN FUEL GAS PRODUCED IN PILOT-SCALE PRESSURIZED FLUIDIZED-BED GASIFIER

Integrated Gasification Combined Cycle (IGCC) process, incorporating p ressurized gasification of solid fuels (coal, peat, biomass) and hot g as cleanup, is being developed worldwide to generate power with high e fficiency and in an environmentally acceptable manner. The gasifier pr oduct gas contains, among others, ammonia and to a lesser extent hydro gen cyanide (HCN) which are converted to oxides of nitrogen (NOx) when the gas is combusted in the gas turbine. Several nickel-based catalys ts were developed and evaluated for decomposition of ammonia present i n the gasifier product gas, at Enviropower's 15 MW(th) pilot plant in coal- and biomass-gasification tests. Up to 75% of ammonia in the prod uct gas was decomposed at 800-900 degrees C temperature range and 12-2 2 bar pressure.