CATALYTIC COMBUSTION FOR INDUSTRIAL GAS-TURBINES

This brief review provides a general account of work directed at the u se of catalytic combustion in gas turbine engines. A major potential a dvantage of using catalytic combustion is that the fuel can be burnt e fficiently at temperatures low enough (<1500''C) to avoid significant oxidation of atmospheric nitrogen. This advantage was less important w hen catalytic combustion was demonstrated in the 1970's than it is tod ay and received relatively little attention until the following decade . After discussion of the principles involved in the design of a combu stor that must meet the mixing, size, performance and durability goals of a based gas turbine application, the review turns to accounts of e xperiments conducted on a laboratory scale with simple configurations. These established basic operating parameters for satisfactory combust ion performance and led to larger scale work and to prototype design c oncepts for industrial gas turbines in the late 70's and early 80's. T est results were encouraging but were not pursued definitively in the U.S.A. Activity continued at several centres in Japan, with exploratio n of a number of different catalyst arrangements, geometries, and cont rol systems, again with encouraging results. At the same time, there h as been renewed interests in the U.S.A, and in Europe, spurred largely by the emphasis on reducing emissions of nitrogen oxides (NOx). The p aper concludes with suggestions for further development of catalytical ly stabilized combustion systems for gas turbines. These systems must ensure adequate pre-catalyst temperature, with evenly premixed fuel an d air, and sufficient temperature rise across the catalyst to ensure e ffective completion of reaction in a homogeneous reaction mode. The ou tstanding problems are largely concerned with questions of catalyst in tegrity and longevity in practical configurations and realistic engine operating conditions.