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Kinetic Studies of CO2 Gasification by Non-isothermal Method on Fly Ash Char

비등온법에 의한 비산재 촤의 CO2 가스화 특성

  • Kang, Suk-Hwan (Plant Engineering Center, Institute for Advances Engineering (IAE)) ;
  • Ryu, Jae-Hong (Plant Engineering Center, Institute for Advances Engineering (IAE)) ;
  • Lee, Jin-Wook (Plant Engineering Center, Institute for Advances Engineering (IAE)) ;
  • Yun, Yongseung (Plant Engineering Center, Institute for Advances Engineering (IAE)) ;
  • Kim, Gyoo Tae (SK Innovation Global Technology) ;
  • Kim, Yongjeon (SK Innovation Global Technology)
  • 강석환 (고등기술연구원 플랜트엔지니어링센터) ;
  • 류재홍 (고등기술연구원 플랜트엔지니어링센터) ;
  • 이진욱 (고등기술연구원 플랜트엔지니어링센터) ;
  • 윤용승 (고등기술연구원 플랜트엔지니어링센터) ;
  • 김규태 (SK이노베이션(주)) ;
  • 김용전 (SK이노베이션(주))
  • Received : 2013.03.13
  • Accepted : 2013.06.08
  • Published : 2013.08.01

Abstract

For the purpose of utilizing fly ash from gasification of low rank coal, we performed the series of experiments such as pyrolysis and char-$CO_2$ gasification on fly ash by using the thermogravimetric analyzer (TGA) at non-isothermal heating conditions (10, 20 and $30^{\circ}C/min$). Pyrolysis rate has been analyzed by Kissinger method as a first order, the reliability of the model was lower because of the low content of volatile matter contained in the fly ash. The experimental results for the fly ash char-$CO_2$ gasification were analyzed by the shrinking core model, homogeneous model and random pore model and then were compared with them for the coal char-$CO_2$ gasification. The fly ash char (LG coal) with low-carbon has been successfully simulated by the homogeneous model as an activation energy of 200.8 kJ/mol. In particular, the fly ash char of KPU coal with high-carbon has been successfully described by the random pore model with the activation energy of 198.3 kJ/mol and was similar to the behavior for the $CO_2$ gasification of the coal char. As a result, the activation energy for the $CO_2$ gasification of two fly ash chars don't show a large difference, but we can confirm that the models for their $CO_2$ gasification depend on the amount of fixed carbon.

저급탄의 가스화에서 얻은 비산재를 활용하기 위한 목적으로 비산재의 열분해와 비산재 촤의 $CO_2$ 가스화반응에 대한 실험을 비등온의 승온 조건(10, 20, $30^{\circ}C$/min)에서 TGA를 이용하여 수행하였다. 비산재의 열분해 속도는 1차의 열분해 모델(Kissinger법)에 의해 해석하였지만, 비산재에 포함된 휘발분의 함량이 낮아 모델의 신뢰도는 낮게 평가되었다. 비산재 촤의 $CO_2$ 가스화반응에 대한 실험결과는 미반응핵 모델, 균일반응 모델 및 랜덤 기공 모델 등으로 해석하여 석탄 촤의 $CO_2$ 가스화반응 결과와 비교하였다. 저탄소가 함유된 비산재 촤(LG탄)는 200.8 kJ/mol의 활성화 에너지로 균일반응 모델의 의해 잘 모사되었으며, 고탄소가 함유된 비산재 촤(KPU탄)의 경우에는 198.3 kJ/mol의 활성화 에너지로 석탄 촤의 $CO_2$ 가스화 특성과 유사하게 랜덤 기공 모델의 의해 잘 모사되었다. 결과로서, 두 비산재 촤의 $CO_2$ 가스화반응에 대한 활성화 에너지는 큰 차이를 나타내지는 않았지만, 고정탄소의 함량에 따라 적용할 수 있는 모델이 다르다는 것을 확인할 수 있었다.

Keywords

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