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Effect of Co-firing PKS and Coal on Flame Structure in a Pulverized Coal Swirl Burner

미분탄 스월버너에서 PKS와 석탄 혼소가 화염 구조에 미치는 영향

  • Shin, Minho (School of Mechanical Engineering, Pusan National University) ;
  • Sung, Yonmo (School of Mechanical Engineering, Pusan National University) ;
  • Choi, Minsung (School of Mechanical Engineering, Pusan National University) ;
  • Lee, Gwangsu (Business Development Department, Korea Southern Power Co., Ltd., KOSPO) ;
  • Choi, Gyungmin (School of Mechanical Engineering, Pusan National University) ;
  • Kim, Duckjool (School of Mechanical Engineering, Pusan National University)
  • 신민호 (부산대학교 기계공학부) ;
  • 성연모 (부산대학교 기계공학부) ;
  • 최민성 (부산대학교 기계공학부) ;
  • 이광수 (한국남부발전 부산발전본부) ;
  • 최경민 (부산대학교 기계공학부) ;
  • 김덕줄 (부산대학교 기계공학부)
  • Received : 2016.09.24
  • Accepted : 2016.10.30
  • Published : 2016.12.30

Abstract

Flame structure of co-firing coal and palm kernel shell (PKS) was investigated in a pulverized coal swirl burner by particle image velocimetry (PIV). The pulverized coal swirl flame is operated with a PKS blending ratio of 10%, 20%, and 30%. For all operating conditions, flame structures such as internal recirculation zone (IRZ), outer recirculation zone (ORZ), and exhaust tube vortex (ETV) were observed. In the center of flame, the strong velocity gradient is occurred at the stagnation point where the volatile gas combustion actively takes place and the acceleration is increased with higher PKS blending ratio. OH radical shows the burned gas region at the stagnation point and shear layer between IRZ and ORZ. In addition, OH radical intensity increases for a co-firing condition because of high volatile matter from PKS. Because the volatile gas combustion takes place at lower temperature, co-firing condition (more than 20%) leads to oxygen deficiency and reduces the combustibility of coal particle near the burner. Therefore, increasing PKS blending ratio leads to higher OH radical intensity and lower temperature.

Keywords

References

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