화학공학소재연구정보센터
홈 로그인 로그아웃 연락처 사이트맵
HWAHAK KONGHAK, Vol.39, No.3, 333-339, June, 2001
Export Citation
순환공정의 수평관에서 농후상 기류수송의 경계유속
Critical Velocity for the Dense-Conveying in a Horizontal Pipe of a Circulation Process
박은호, 홍성선, 홍성선1, 이창근1, †, 진경태1
  • 충북대학교 화학공학과, 충북 360-763
  • 1한국에너지기술연구소 유동층기술연구센터, 대전 305-343
Eun-Ho Park, Sung-Sun Hong, Sung-Sun Hong1, Chang-Keun Yi1, †, and Gyoung-Tae Jin1
  • Department of Chemical Engineering, Chungbuk National University, Chungbuk 360-763, Korea
  • 1Fluidization Research Center, Korea Institute of Energy Research, Daejeon 305-343, Korea
E-mail:
초록
고체순환장치의 수평관에서 차압계를 이용하여 농후상영역과 plug 흐름사이의 경계유속을 측정하였다. 수평관은 직경 0.034 m, 길이 1.8 m로 Plexiglas로 만들어졌다. 본 실험에서는 FCC 촉매, 아연계탈황제, polyethylene 입자를 사용하였다. 본 연구에서는 경계유속을 결정하기 위해 수평관에서 차압, 표준편차와 고체수송속도를 측정하였다. 실험결과 경계유속은 고체수송속도가 증가할수록 증가하였으나 압력범위 1.0-2.0 atm에서는 별다른 변화가 없었다. 입자의 밀도, 직경, 고체수송속도를 사용하여 경계유속을 예측할 수 있는 상관식을 제시하였다. 가압순환공정에 있어 경계유속 이하의 유속에서 발생하는 plug flow는 가압시스템의 수평관 전후의 압력균형에 불안정한 요소로 작용하였다.
Critical velocities were measured by differential pressure transducers in a solid circulation experimental apparatus which was a 1.8 m in length, 0.034 m in diameter of Plexiglas horizontal pipe. Three kinds of particles of FCC catalyst, zinc titanate and polyethylene were used. Pressure drop, standard deviation of pressure drop fluctuations and solid conveying rate were measured to determine the critical velocity. Critical velocity increased with increasing solids conveying rate, however, there was little effect of the pressure on the critical velocity in the range from 1.0 to 2.0 atm. The critical velocity was correlated in terms of particle density, diameter and solid conveying rate. Unstable Pressure balance was occurred at front section and at rear section of a horizontal pipe in a pressurized circulation system when it was disturbed by plugs at a velocity less than U(cr).
Keywords:Critical Velocity;Dense-Conveying;Pneumatic Transport;Horizontal Pipe
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