Pyrolysis, Partial Oxidation, and Combustion Characteristics of Micro Algae

미세 조류의 열분해, 부분산화, 연소 특성 연구

  • Seo, Myung Won (Department of Chemical and Biomolecular Engineering, Energy and Environment Research Center, Korea Advanced Institute of Science and Technology(KAIST)) ;
  • Kim, Sang Done (Department of Chemical and Biomolecular Engineering, Energy and Environment Research Center, Korea Advanced Institute of Science and Technology(KAIST)) ;
  • Na, Jeong Geol (Gasification Research Group, Korea Institute of Energy Research(KIER)) ;
  • Lee, See Hoon (Gasification Research Group, Korea Institute of Energy Research(KIER))
  • 서명원 (한국과학기술원 생명화학공학과 및 에너지환경연구센터) ;
  • 김상돈 (한국과학기술원 생명화학공학과 및 에너지환경연구센터) ;
  • 나정걸 (한국에너지기술연구원 가스화연구그룹) ;
  • 이시훈 (한국에너지기술연구원 가스화연구그룹)
  • Received : 2009.10.07
  • Accepted : 2009.10.21
  • Published : 2009.12.31

Abstract

Characteristics of pyrolysis, partial oxidation, combustion of chlorella, which is one species of micro-algae, were determined by using thermobalance reactor(I.D. 5.5 cm, Height 1 m). Effect of reaction temperature($500{\sim}800^{\circ}C$), water content in chlorella(0~60%), and oxygen content(0~21vol%) on thermal decomposition of chlorella were also determined and analyzed to investigate the kinetic characteristics of pyrolysis, partial oxidation and combustion. As the temperature and partial pressure increases, the carbon conversion increases. In case of pyrolysis, carbon conversion and reactivity sharply decreased with increasing moisture content. However, carbon conversion and reactivity decreased at 60% water content in case of partial oxidation and combustion. As reaction temperature and oxygen content increased, carbon conversion increased and the combustion reaction rate equation for chlorella has been presented. $\frac{dX}{dt}=(7.41{\times}10^{-1})$exp$\left(-\frac{19600}{RT}\right)(P_{O_{2}})^{0.209}(1-X)^{2/3}$.

미세 조류의 열화학적 반응 특성을 고찰하기 위하여 열중량 반응기(I.D. 5.5 cm, Height 1 m)를 이용하여 클로렐라의 열분해, 연소, 부분 산화에 따른 실험을 수행하였다. 반응 온도($500{\sim}800^{\circ}C$), 클로렐라의 수분 함유량(0~60%), 산소 농도(0~21%)에 따른 클로렐라의 무게 감량 변화를 관찰하였으며 이를 이용하여 열분해, 연소, 부분 산화 반응 특성을 고찰하였다. 수분 함량이 증가함에 따라 탄소 전환율과 반응성이 감소하는 경향이 발견되었다. 열분해의 경우, 건조 시료(수분 함량 0%)에 비하여 수분 함량이 늘어남에 따라 탄소 전환율과 반응성이 급격하게 감소한 반면, 부분 산화(5%) 및 연소의 경우에는 수분 함량이 60%가 되면서 탄소 전환율 및 반응성이 감소하는 경향이 발견되었다. 반응온도 및 산소의 분압이 증가함에 따라 탄소 전환율은 증가하는 경향을 보였으며 chlorella의 연소 반응식은 다음과 같다. $\frac{dX}{dt}=(7.41{\times}10^{-1})$exp$\left(-\frac{19600}{RT}\right)(P_{O_{2}})^{0.209}(1-X)^{2/3}$.

Keywords

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