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Analysis of Oxygen Combustion Characteristics of a Low Grade Coal Using IEA-CFBC Model

IEA-CFBC 모델을 이용한 저급탄의 순산소 연소 특성 분석

  • Gwak, You Ra (Department of Mineral resources energy engineering, Chonbuk national university) ;
  • Kim, Ye Bin (Department of Mineral resources energy engineering, Chonbuk national university) ;
  • Keel, Sang In (Environment System Research Division, Korea Institute of Machinery and Materials) ;
  • Yun, Jin Han (Environment System Research Division, Korea Institute of Machinery and Materials) ;
  • Lee, See Hoon (Department of Mineral resources energy engineering, Chonbuk national university)
  • 곽유라 (전북대학교 자원에너지공학과) ;
  • 김예빈 (전북대학교 자원에너지공학과) ;
  • 길상인 (한국기계연구원 환경시스템연구본부) ;
  • 윤진한 (한국기계연구원 환경시스템연구본부) ;
  • 이시훈 (전북대학교 자원에너지공학과)
  • Received : 2018.07.07
  • Accepted : 2018.08.14
  • Published : 2018.10.01

Abstract

The application of an oxy-combustion circulating fluidized bed combustor (Oxy-CFBC) for low grade coals has recently developed in the world to meet the continuous increase of energy demand and to achieve the reduction of greenhouse gases. Since demo plants for Oxy-CFBC have been developed, the combustion properties of Oxy-CFBC in various operation conditions, such as gas flow rates, combustion temperature, fuel, and so on, should be investigated to develop design criteria for a commercial Oxy-CFBC. In this study, a computational simulation tool for Oxy-CFBC was developed on the basis of the IEA-CFBC (International Energy Agency Circulating Fluidized Bed Combustor) model. Simulation was performed under various conditions such as reaction temperature ($800^{\circ}C{\sim}900^{\circ}C$), oxygen contents (21%~41%), coal feeding rate, Ca/S mole ratio (1.5~4.0), and so on. Simulation results show that the combustion furnace temperature is higher in oxy 1 than air fired. However, the temperature gradient tended to decrease with increasing oxy mixing percent. In case of $SO_x$, the higher the Ca/S mole ratio and oxy mixing percent, the higher the desulfurization efficiency.

Keywords

Circulating fluidized bed;Computational simulation;Oxy combustion;Air combustion;Low grade coal

Acknowledgement

Supported by : 한국연구재단, 한국전력공사

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