촉매 연소기에서 희박 예혼합기의 연소특성

Abstract

The aim of this paper is to investigate combustion characteristics of lean premixed mixture stabilized by catalytic surface reaction. The catalytic combustor consisted of a catalyst bed and a thermal combustor. The catalyst bed was made of two stage, Pd catalyst in the first stage and Pt catalyst in the second stage. Auto ignition of lean mixture took place in the thermal combustor. Ignihon temperature was about 810∼820℃ TIC at the fuel-air ratio of 1.5∼3.0% and the mixture velocity of 11∼18m/sec. The position of flame front in the thermal combustor moved toward back as preheat temperature increased and fuel-air ratio decreased. The flame supported by surface reaction was stabilized without any flame stabilizers. NOx emissions from the catalytic combustor were below 2.0ppm (O2 15%) when gas temperature was limited below 1350℃. This result demonstrates that NOx emission from the catalytic combustor is much low comparing with conventional combustors.