유기물자원화 (Journal of the Korea Organic Resources Recycling Association)

  • 제23권4호
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  • Pages.95-103
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  • 2015
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  • 1225-6498(pISSN)
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  • 2508-3015(eISSN)
유기성자원학회 (Korea Organic Resources Recycling Association)
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도계폐기물의 열가수분해 반응에 따른 열전달 특성 연구

A Study on Heat Transfer Characteristics according to Thermal Hydrolysis Reaction of Poultry Slaughter Waste

  • 송형운 (고등기술연구원 플랜트엔지니어링센타) ;
  • 정희숙 (고등기술연구원 플랜트엔지니어링센타) ;
  • 김충곤 ((주)도화엔지니어링)
  • 투고 : 2015.11.23
  • 심사 : 2015.12.08
  • 발행 : 2015.12.30
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초록

본 연구에서 목적은 열가수분해 반응기에 최적설계를 위해 반응온도에 따른 도계폐기물의 열전도도를 정량하는 것이다. 이에 반응온도에 따른 탈수슬러지의 열전도도를 연속적으로 정량한 결과, 반응온도가 증가할수록 열가수분해 반응에 의한 고온, 고압에 의해 슬러지가 열적으로 가용화된다. 따라서, 슬러지 세포내에 결합수가 자유수로 용출되어 고상의 탈수슬러지가 액상의 슬러리로 상태가 변화된다. 그 결과 반응초기인 반응온도 $20^{\circ}C$에서 도계슬러지에 열전도도가 물에 비해 2.11배정도 낮지만 $200^{\circ}C$에서는 도계슬러지의 열전도도가 $0.677W/m{\cdot}^{\circ}C$로 물과 유사하다. 따라서 열가수분해에 의한 슬러지의 물리적 특성변화는 열전달 효율에 매우 중요한 인자임을 확인하였고, 열가수분해반응기 최적 설계를 위한 경계조건으로 실험 측정값과 일치도가 99.69%인 반응온도에 따른 열전도도 함수를 도출하였다.

The purpose of this study was performed to quantitatively measure the thermal conductivity of poultry slaughter waste with variation of reaction temperature for optimal design of thermal hydrolysis reactor. We continuously quantified the thermal conductivity of dehydrated sludge related to the reaction temperature. As the reaction temperature increased, the dehydrated sludge is thermally liquefied under high temperature and pressure by the thermal hydrolysis reaction. Therefore, the bond water in the sludge cells comes out as free water, which changes the dehydrated sludge from a solid phase to slurry of a liquid phase. As a result, the thermal conductivity of the its sludge was more than 2.11 times lower than that of the water at $20^{\circ}C$. However, the thermal conductivity of the sludge approached to $0.677W/m{\cdot}^{\circ}C$ of water at $200^{\circ}C$, experimentally substantiating liquefaction of the dehydrated sludge. Therefore, we confirmed that the change in physical properties due to thermal hydrolysis appears to be an important factor for heat transfer efficiency. And the thermal conductivity function related to reaction temperature was derived to give the boundary condition for the optimal design of the thermal hydrolysis reactor. The consistency of the calculated function was 99.69%.

키워드

참고문헌

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