Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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An Experimental Investigation of the Effect of Particle Size on the Combustion Characteristics of Pulverized Sub-Bituminous Coal with Low Calorific Value by Using an LFR System

LFR 장치를 이용한 입자 크기 변화에 따른 저열량 아역청 미분탄의 연소특성에 관한 실험적 연구

  • Jeon, Chung-Hwan (School of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Kim, Yong-Gyun (School of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Kim, Jae-Dong (School of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Kim, Gyu-Bo (Pusan Clean Coal Center, Pusan Nat'l Univ.) ;
  • Song, Ju-Hun (School of Mechanical Engineering, Pusan Nat'l Univ.)
  • 전충환 (부산대학교 기계공학부) ;
  • 김용균 (부산대학교 기계공학부) ;
  • 김재동 (부산대학교 기계공학부) ;
  • 김규보 (부산대학교 화력발전에너지분석기술센터) ;
  • 송주헌 (부산대학교 기계공학부)
  • Published : 2010.03.01
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Abstract

In this study, the effect of particle size on the combustion characteristics of pulverized sub-bituminous coal was experimentally investigated. A laminar-flow-entrained reactor was designed and implemented to realize the desired heating ratio and temperature corresponding to the combustion atmosphere of a pulverized-coal-fueled furnace. The flame length and structure of burning particles according to different sizes were investigated. Coal combustion processes were clearly distinguished by direct visual observation of the flame structure. The onset point of volatile ignition is greatly affected by changes in the particle size, and the burning time of the volatiles is least affected by changes in the particle size. The length and instability of char flame also increase with the increase of the particle size. However, the char consumption rate within the residential time remains nearly constant.

본 연구는 아역청탄의 미분탄 연소특성에 있어서, 입자크기가 미치는 영향을 알고자 실험을 통해 고찰한 것이다. 본 연구를 위하여, 온도 및 온도 상승률을 고려해 볼 때, 실제 미분탄 연소로의 환경을 잘 구현할 수 있는 층류반응기를 설계하고 이용하였다. 크기가 다른 미분탄 입자들이 탈 때 형성되는 화염구조 및 길이를 본 반응기를 이용해 조사하였다. 육안으로 관찰된 화염구조로부터 석탄연소과정들을 분명하게 구분할 수 있었다. 입자의 크기변동은 휘발분 점화개시점에 미치는 영향이 큰 반면, 휘발분의 연소시간에 미치는 영향은 가장 적었다. 입자의 크기가 커질수록 촤의 화염길이도 증가하였다. 화염불안정성 역시 입자가 커짐에 따라 증대되었다. 일정한 체류시간 간격내에서의 촤의 소비율은 거의 일정하였다.

Keywords

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