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 the IGCC process to meet NOx standards and maintain the thermal efficiency of the process, tests were carried out with a 7.5 cm pressurized reactor 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 determined. The simulated coal gas composition was varied to allow assessment of the effect of contaminants (sulfur compounds and tars) on the ammonia decomposition efficiency of five catalysts under otherwise identical operating conditions. The results show that two of the catalysts tested are capable of efficiently reducing the concentration of ammonia in the gas.