Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
권호 표지

The Minimum Fluidization Velocity of Gaussian Distribution Particle System According to Standard Deviation

Gaussian 분포의 입자군의 표준편차에 따른 최소유동화속도

  • Jang, Hyun Tae (Dept. of Chem. Eng., Hanseo University) ;
  • Park, Tae Sung (Carbon Dioxide Reduction Sequestration R&D Center, Korea Institute of Energy Research) ;
  • Cha, Wang Seog (Dept. of Civil and Environ. Eng., Kunsan Nat'l University)
  • 장현태 (한서대학교 화학공학과) ;
  • 박태성 (에너지기술연구원 이산화탄소처리 및 저감기술개발 사업단) ;
  • 차왕석 (군산대학교 토목환경공학부)
  • Received : 2008.01.17
  • Accepted : 2008.04.01
  • Published : 2008.06.30
Download PDF
⟨ Previous Next ⟩

Abstract

The present study investigated the applicability of the minium fludization velocity measuring method using linear regression analysis between the standard deviation of pressure fluctuation and gas velocity in multi-particle sand on a fluidized bed 0.109 in inner diameter. We measured minium fludization velocity according to the standard deviation of particle distribution in Gaussian distribution. The measured value compared with other researchers' equations. The minium fludization velocity derived from the linear regression analysis of the standard deviation of pressure fluctuation and pressure drop inside the bed. We also found that the minium fludization velocity of a multi-particle system using the standard deviation of pressure fluctuation must be measured at freely bubbling region.

내경 0.109 m의 유동층에서 다입자경 모래에 대한 압력요동의 표준편차와 유속간의 선형회귀분석을 이용한 최소유동화속도 측정법의 적용성을 조사하였다. 다입자경 모래를 평균입자크기가 같은 Gaussian 분포에서 입자분포의 표준편차에 따른 최소유동화속도를 측정하고, 측정치를 타 연구자들의 식과 비교 검토하였다. 압력요동의 표준편차 값 선형회귀분석법과 층내 압력강하로부터 구한 최소유동화속도를 구하였다. 최소유동화속도 결정에서 유속 범위는 혼합도가 낮은 유속범위와 free bubbling 영역 이상을 제외한 범위값 이어야 하며, 이 유속범위에서 측정위치는 혼합이 양호한 층 중앙이 가장 적절하다.

Keywords

References

  1. Davidson, J. F., Clift, R. and Harrison, D., "Fluidization," 2nd ed. Academic Press, London(1985)
  2. Hong, S. C., Jo, B. R., Doh, D. S. and Choi, C. S., "Determination of Minimum Fluidization Velocity by the Statistical Analysis of Pressure Fluctuations in a Gas-solid Fluidized Bed," Powder Technol., 60, 215-221(1990) https://doi.org/10.1016/0032-5910(90)80121-E
  3. Verloop, J. and Heertjes, P. M., "Periodic Pressure Fluctuations in Fluidized Beds," Chem. Eng. Sci., 29, 1035-1042(1974) https://doi.org/10.1016/0009-2509(74)80096-5
  4. Chiba, S., Chiba, T., Ninow, A. W. and Kobayashi H., "The Minimum Fluidisation Velocity, Bed Expansion and Pressure-drop Profile of Binary Particle Mixtures," Powder Technol., 22, 255-269 (1979) https://doi.org/10.1016/0032-5910(79)80031-5
  5. Cheung, L., Ninow, A. W. and Rowe, P. N., "Minimum Fluidisation Velocity of a Binary Mixture of Different Sized Particles," Chem. Eng. Sci., 29, 1301-1303(1974) https://doi.org/10.1016/0009-2509(74)80137-5
  6. Cha, W. S., Hong, S. C., Oh, K. J. and Doh, D. S., "Minimum Fluidization Velocity and Fluidization Characteristics of Binary Particle System," HWAHAK KONGHAK, 30(3), 641-648(1992)
  7. Bendart, J. S. and Piersol, "Random Data," John Wiley, New York(1971)
  8. Abdulrahim Ahmad Alzahrani and Noor Wali, M. M., "A Study of Pressure Drop Fluctuations in a Gas-solids Fluidized Bed," Powder Technol, 76, 185-189(1993) https://doi.org/10.1016/S0032-5910(05)80026-9
  9. Rowe P. N. and Yacono C. X. R., "The Bubbling Behaviour of Fine Powders When Fluidised," Chem. Eng. Sci., 31(12), 1179-1192(1976) https://doi.org/10.1016/0009-2509(76)85027-0
  10. Puncochar, M. and Drahos, J., "Origin of pressure fluctuations in fluidized beds," Chem. Eng. Sci., 60(5), 1193-1197(2005) https://doi.org/10.1016/j.ces.2004.09.054