Effect of Temperature on Gas Hold-up in Aerated Stirred Tanks

Abstract

Abstract: Gas holdups in ambient gassed and hot sparged systems with multiple modern impellers and
the effect of temperature on gas holdup are reported. The operating temperature has a great
impact on gas holdup though the gas dispersion regime in the hot sparged system is similar
to the ambient gassed condition. The gas holdup under the elevated temperature and the
ambient gassed operation is successfully correlated. With the same total gas flow rate and
power input, the gas holdup in the hot sparged system (say near the boiling point) is only
about half of that in the ambient system. The results imply that almost all existing hot
sparged reactors have been designed on the basis of incorrect estimates of the gas holdup
during operation.

Key words: gas holdup, temperature effect, gas dispersion, hot sparged reactors, radar probe, stirred tank

摘要： Gas holdups in ambient gassed and hot sparged systems with multiple modern impellers and
the effect of temperature on gas holdup are reported. The operating temperature has a great
impact on gas holdup though the gas dispersion regime in the hot sparged system is similar
to the ambient gassed condition. The gas holdup under the elevated temperature and the
ambient gassed operation is successfully correlated. With the same total gas flow rate and
power input, the gas holdup in the hot sparged system (say near the boiling point) is only
about half of that in the ambient system. The results imply that almost all existing hot
sparged reactors have been designed on the basis of incorrect estimates of the gas holdup
during operation.

关键词: gas holdup;temperature effect;gas dispersion;hot sparged reactors;radar probe;stirred tank

GAO Zhengming, SHI Litian. Effect of Temperature on Gas Hold-up in Aerated Stirred Tanks[J]. .

高正明, 施力田. 搅拌槽内温度对气含率的影响[J]. CIESC Journal.

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