CATALYTIC DECOMPOSITION OF AMMONIA IN A FUEL GAS AT HIGH-TEMPERATURE AND PRESSURE

In connection with the purification of fuel gas for gas turbines in th e IGCC process to meet NOx standards and maintain the thermal efficien cy of the process, tests were carried out with a 7.5 cm pressurized re actor to decompose ammonia at high temperature (700-900 degrees C) and pressure (2 MPa) using Ni-bassd catalysts. The effects of temperature , pressure, ammonia concentration and gas residence time were determin ed. The simulated coal gas composition was varied to allow assessment of the effect of contaminants (sulfur compounds and tars) on the ammon ia decomposition efficiency of five catalysts under otherwise identica l operating conditions. The results show that two of the catalysts tes ted are capable of efficiently reducing the concentration of ammonia i n the gas.