In concurrent bubble columns the longitudinal mass and thermal dispersion coefficients were determined. The both coefficients agreed well with each other. This shows that the mechanism of the thermal dispersion in the bubble column is also governed by liquid mixing.
The dispersion coefficient E
l, is correlated with experimental conditions in three regions, which are classified by the value of slip velocity of gas bubbles, u
s. At u
s>25cm/sec, E
l obtained in columns of the same diameter is related apparently only on the superficial gas velocity in the column, but it is independent on the liquid property and the size of gas bubbles. E
l is also proportional to one and a half powers of the column diameter. At u
s<20cm/sec, E
l is represented by a plot of Pé vs. ReP, where the average bubble diameter is taken as the characteristic length. At 20 > u
s > 25cm/sec, no correlation for E
l was obtained.
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