Gas Hold-Up in a Reactor with Dual System of Impellers*
نویسندگان
چکیده
Results of experimental studies of gas hold-up in a liquid stirred mechanically in a reactor, which was equipped with double stirrers on a common shaft, are presented. Coalescing and noncoalescing gas—liquid systems were tested. The measurements were carried out for aqueous solutions of glucose and glucose sirup, as well as for different configurations of dual high-speed impellers. Stirred tank with inner diameter D = 0.288 m was filled with a liquid up to the height H = 2D. Experimental studies of gas hold-up in the coalescing and noncoalescing gas—liquid systems stirred using dual system of high-speed impellers show that gas hold-up φ for the noncoalescing systems is considerably higher than that for the coalescing ones. The configuration of dual system of impellers used in the study slightly affects only gas hold-up and this effect can be neglected. The dependence of gas hold-up φ on the specific power consumption Pg/VL and superficial gas velocity wog for coalescing and noncoalescing systems can be described by means of eqns (2) and (3), respectively.
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