Journal of Korean Society of Environmental Engineers (대한환경공학회지)

Korean Society of Environmental Engineers (대한환경공학회)
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NOx Emission Characteristics Depending on the Variations in Yaw Angle of the Secondary Air Nozzles in a Coal Fired Boiler

연소용 이차공기 수평분사각에 따른 질소산화물(NOx) 배출특성

  • 김영주 (한전전력연구원 신발전연소그룹) ;
  • 박호영 (한전전력연구원 신발전연소그룹) ;
  • 이성노 (충남대학교 기계공학과)
  • Received : 2009.02.19
  • Accepted : 2009.04.28
  • Published : 2009.04.30
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Abstract

Three dimensional numerical analysis for the coal fired boiler has been performed to investigate the effect of yaw angle variation of the secondary air nozzles on the combustion characteristics and NOx emission. It was found that the prediction gives a good agreement with plant data. The increase in yaw angle up to $20^{\circ}$ have results in the decrease in NOx emission at furnace exit and recirculation flow intensity, together with the increase of unburned carbon in ash. It also has been recognized the remarkably change in configuration of fire ball with increase in yaw angle. The results from this study would be valuable in the case of the combustion modification of the corner firing coal-fired utility boiler.

국내 석탄화력발전소의 대용량 보일러를 대상으로 연소용 이차공기의 수평분사각을 변경한 경우에 대하여 화로에서의 연소특성과 NOx 발생특성을 전산유체역학적으로 해석하였다. 열유동해석 결과를 실제 운전데이터와 비교하여 해석의 신뢰성을 확인하할 수 있었다. 분사각을 $20^{\circ}$까지 증가시킬 경우 노즐 근처에서의 재순환유동 감소, 화로출구 NOx 감소와 미연분 증가를 가져왔으며 화구의 형태가 많이 변화되는 것을 관찰하였다. 본 연구결과는 A화력발전소의 연소방식을 변경하는 경우 기본적인 설계 및 운전 데이터로 활용하고자 한다.

Keywords

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