| Summary: | 碩士 === 國立臺灣科技大學 === 化學工程技術研究所 === 86 === On the basis of previous research, this study searched the suitable scaleup criticism for a unique draft tube type gas-induced reactor. Under the geometrical sImilarity, a reactor with larger scale was made to compare the performances of reactor in different scales.
It is found that the size of draft tube has obvious effects on the flow pattern of fluids, the onset speed for gas induction, and the specific power consumption. After the evaluation, the better length of draft tube is equal to twice of the impeller diameter. The equation N1/N2=(D1.2=/D1.3)" was adopted to indicate the relationship between the operational impeller speed and the tank diameter after scaleup. In experimental results, the suitable value of n for the formation of gas induction (i.e Surface motion ) in the present reactor is 0.57, being different to the value 0.5 for an unbaffled agitated tank.It is due to the installation of a draft tube in the present gas-induced reactor. In addition, the value of n for the scaleup based on the same specific power consumption (i. e. the same mass transfer effect)is in the range of 0.60-0.66. It is depended on the working liquid level.
Further investigations are needed to verify the above mentioned two criticism for the scaleup of gas-induced reactor.
|
|---|
