Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Modeling of Solid Circulation in a Fluidized-Bed Dry Absorption and Regeneration System for CO2 Removal from Flue Gas

연소기체로부터 CO2 회수를 위한 건식 유동층 흡수-재생 공정의 고체순환 모사

  • Choi, Jeong-Hoo (Department of Chemical Engineering, Innovartive Environmental Technology Center, Konkuk University) ;
  • Park, Ji-Yong (Department of Chemical Engineering, Innovartive Environmental Technology Center, Konkuk University) ;
  • Yi, Chang-Keun (Korea Institute of Energy Research) ;
  • Jo, Sung-Ho (Korea Institute of Energy Research) ;
  • Son, Jae-Ek (Korea Institute of Energy Research) ;
  • Ryu, Chong Kul (Korea Electric Power Research Institute) ;
  • Kim, Sang-Done (Department of Biomolecular and Chemical Engineering, KAIST)
  • 최정후 (건국대학교 화학공학과, 차세대 환경기술센타) ;
  • 박지용 (건국대학교 화학공학과, 차세대 환경기술센타) ;
  • 이창근 (한국에너지기술연구원) ;
  • 조성호 (한국에너지기술연구원) ;
  • 손재익 (한국에너지기술연구원) ;
  • 류청걸 (전력연구원) ;
  • 김상돈 (한국과학기술원 생명화학공학과)
  • Received : 2004.10.11
  • Accepted : 2004.12.01
  • Published : 2005.04.30
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Abstract

An interpretation on the solid circulation characteristics in a fluidized-bed process has been carried out as a first step to simulate the dry entrained-bed absorption and bubbling-bed regeneration system for $CO_2$ removal from flue gas. A particle population balance has been developed to determine the solid flow rates and particle size distributions in the process. Effects of principal process parameters have been discussed in a laboratory scale process (absorption column: 25 mm i.d., 6 m in height; regeneration column: 0.1 m i.d., 1.2 m in height). The particle size distributions in absorption and regeneration columns were nearly the same. As gas velocity or static bed height in the absorption column increased, soild circulation rate and feed rate of fresh sorbent increased, however, mean particle diameter decreased in the absorption column. As cut diameter of the cyclone of the absorption column increased, solid circulation rate decreased, whereas feed rate of fresh sorbent and mean particle diameter in the absorption column increased. As attrition coefficient of sorbent particle increased, solid circulation rate and feed rate of fresh sorbent increased but mean particle diameter in the absorption column decreased.

기체 수송층 흡수탑과 기포 유동층 재생탑으로 구성된 $CO_2$ 회수 공정에 대한 해석의 첫 단계로 이 공정에서 고체 순환특성을 해석하였다. 흡수제 고체 입자에 대한 입도별 물질수지를 해석하여 공정의 흐름에서 고체 흐름량과 입도 분포를 결정하였다. 실험실 규모 공정(흡수탑: 직경 25 mm, 높이 6 m; 재생탑: 직경 0.1 m, 높이 1.2 m)에서 고체순환특성을 모사하였다. 흡수탑의 입도분포는 재생탑의 입도분포와 거의 같았다. 흡수탑에서 유속과 정체층 높이가 증가함에 따라서 고체순환량과 새 흡수제 주입량은 증가하였다. 반면에 흡수탑 내 입자의 평균입경은 감소하였다. 흡수탑사이클론의 절단입도가 증가함에 따라서 고체순환속도는 감소하였으며, 새 흡수제 주입속도와 흡수탑 내 입자의 평균 입경은 증가하였다. 흡수제 입자의 마모계수가 증가함에 따라서 고체순환속도는 증가하고, 새 흡수제 주입속도는 증가하며, 흡수탑 내 입자의 평균입경은 감소하였다.

Keywords

Acknowledgement

Supported by : 과학기술부

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