Characteristics of Combustion and Emission for Synthetic Natural Gas in CNG Engine

CNG엔진에서 합성가스 연료의 연소 및 배기 특성 평가

Lee, Sungwon;Lim, Gihun;Park, Cheolwoong;Choi, Young;Kim, Changgi

  • Received : 2012.06.13
  • Accepted : 2015.11.04
  • Published : 2015.12.31


Synthetic natural gas(SNG), acquired from coal, is regarded as an alternative to natural gas since a rise in natural gas due to high oil price can be coped with it. In the present study, 11-liter heavy duty compressed natural gas(CNG) engine was employed in order to examine the combustion and emission characteristics of SNG. The simulated SNG, made up 90.95% of methane, 6.05% propane and 3% hydrogen was used in the experiment. Power output, thermal efficiency, combustion stability and emission characteristics were compared to those with CNG at the same engine operating conditions. Knocking phenomenon was also analyzed at 1260 rpm, full load condition. Combustion with SNG was more stable than CNG. Nitrogen oxides emissions increased while Carbon dioxides emissions decreased. Anti-knocking characteristics were improved with SNG.


synthetic natural gas(SNG);compressed natural gas(CNG);power output;thermal efficiency;combustion stability;emission;knocking margin


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