MILD (Moderate and Intense Low oxygen Dilution) combustion using high temperature exhaust gas recirculation is applied to solid fuels of dried sewage sludge and pulverized coal combustion to investigate the effect of reduction of NOx emission in a pilot scale combustor. High temperature exhaust gas recirculation is accomplished by entraining high temperature exhaust gas to air jets at just exit of the combustion chamber without a heat exchanger. High temperature exhaust gas recirculation makes the solid fuel flame stable and extremely uniform color and uniform temperature distribution. NOx concentration at the combustor exit was 62% and 40% less in the high temperature exhaust recirculation MILD combustion compared with the conventional combustion using air jet only for sewage sludge and pulverized coal respectively.

• 심성훈(한국기계연구원 환경기계시스템연구실) | Sung-Hoon Shim Corresponding author
• 정상현(한국기계연구원 환경기계시스템연구실) | Sang-Hyun Jeong
• 하지수(계명대학교 환경과학과) | Ji-Soo Ha