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Gold Science and Technology ›› 2015, Vol. 23 ›› Issue (4): 80-85.doi: 10.11872/j.issn.1005-2518.2015.04.080

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The Improved Sampling Method for the Measurement of  Phase Holdup Distributions in Gas-Liquid-Solid Stirred Tank

CAO Junya1,MA Bin1,2,LI Xiangyang2,YANG Chao2,MAO Zaisha2,ZHANG Guangji2   

  1. 1.School of Chemical and Environmental Engineering,China University of Mining  Technology(Beijing),Beijing   100083,China;
    2.Key Laboratory of Green Process and Engineering,Institute of Process Engineering,Chinese Acadamy of Sciences,Beijing   100190,China
  • Received:2015-05-15 Revised:2015-06-23 Online:2015-08-28 Published:2015-11-16

Abstract:

The gas-liquid-solid three-phase stirred tank reactor is widely applied in the chemical metallurgy and environment protection.The lack of basic experimental data makes it difficult to scale up a gas-liquid-solid three-phase stirred tank.The concentration distribution of the dispersed phases(bubbles and solid particles) can reflect the characteristics inside the reactor directly and effectively.There is still no reliable measurement technique to effectively reflect the characteristics of local phase holdup distribution inside the reactor.This paper reports a sampling tube with a bell mouth to measure the local holdup,and its feasibility is tested.The measurement is more accurate when opening size is 3d and it is more likely to collect gas when opening downwards.Improved sampling method is applied to measure the local phase holdup in the stirred tank with an air-water-quartz sand three-phase system.The experiments use single-layer Rushton disc turbine(RTD),analysis of these experimental data suggests:The local solid holdup increases in the radial direction while it decreases along the axial distance from the bottom to the top,the local gas holdup decreases in the radial direction,and it is relatively uniform in the axial direction.The present results are qualitatively in conformity with our comprehension of this kind of reactor.

Key words: three-phase stirred tank, sampling method, local phase holdup, radial and axial distribution

CLC Number: 

  • TQ027.2

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