Application of electrical capacitance tomography for gas-solid fluidized bed measurement

doi:10.3969/j.issn.0438-1157.2014.07.012

Abstract

Abstract: Although gas-solid fluidized beds have been widely used in various processes, the development of reliable and non-intrusive measurement techniques for solid-gas two-phase flows in fluidized beds is still attracting considerable attention. Due to its advantages of simple construction and high temporal resolution, electrical capacitance tomography (ECT) has been widely applied in multi-phase flow measurements. This paper reviews the application of ECT in gas-solid fluidized bed measurement, including the measurement of solids distribution, flow regime transition, solids flow velocity, and water content in fluidized bed dryers. The challenges of ECT in gas-solid fluidized bed measurement are also discussed.

Key words: fluidized bed, measurement, fluidization, tomography

摘要： 气固流化床广泛应用于化工、炼油、冶金、电力等工业生产领域。由于流化床中气固两相流动的复杂性，流化床测量方法的研究成为了一个重要的研究领域。电容层析成像（ECT）是20世纪80年代以来发展起来的一种非介入式多相流测量技术，已经在多相流测量领域发挥了重要作用。总结了国内外近年来应用ECT技术进行气固流化床测量的进展，特别是对气固流化床内固体相浓度、流化床流型识别、固体相速度等方面工作进行了总结，并简单介绍了ECT在流化床干燥中的应用，讨论了ECT和其他测量方法结合使用情况。最后对ECT在流化床测量中的局限性和发展方向进行了讨论。

关键词: 流化床, 测量, 流态化, 成像

CLC Number:

TQ028.8

LUO Qin, ZHAO Yinfeng, YE Mao, LIU Zhongmin. Application of electrical capacitance tomography for gas-solid fluidized bed measurement[J]. CIESC Journal, 2014, 65(7): 2504-2512.

罗琴, 赵银峰, 叶茂, 刘中民. 电容层析成像在气固流化床测量中的应用[J]. 化工学报, 2014, 65(7): 2504-2512.

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