Characteristics of Cross-Flow Rotating Packed Bed
Date Issued
2004
Date
2004
Author(s)
Hsu, Yi-Chun
DOI
zh-TW
Abstract
Higee is a process which applys centrifugal force to intensify mass and heat transfer. Centrifugal acceleration is beneficial to the process, such as the less tendency of flooding, and the better mass transfer efficiency. As a result, the size of the equipment as well as the capital cost can be greatly reduced, which is a very important trend in future chemical engineering and industrial development.
In this study, the characteristics of pressure drop of a cross-flow rotating packed bed were investigated. Then the absorption of VOCs into water was carried out to evaluate its mass transfer performance. Factors affecting the overall mass transfer coefficient (Kga) such as rotational speed, liquid and gas flow rate were conferred in this research. Besides, the gas flow pattern with the gas seal or not was compared.
According to the experimental results, the pressure drop increased with both gas rate and rotational speed. The difference in pressure drop between wet bed and dry bed in low rotational speed is smaller than that at high rotational speed. In addition, the pressure in wet bed is slightly lower than that in the dry bed. The characteristics of pressure drop in counter current and cross flow rotating beds were found to be similar.
Overall mass transfer coefficient Kga was found to increase with gas rate, liquid rate, and rotational speed. The initial concentration of the gas stream almost did not influence the overall mass transfer coefficient. Due to the effect of centrifugal force, rotating packed bed had better mass transfer than conventional packed bed. From our analysis, the gas concentration decreased with the height of the packed bed, whereas the liquid concentration increased with the radius of the packed bed. With enough liquid flow rate and rotational speed, the overall mass transfer coefficient Kga increased obviously when the gas seal installed.
The empirical correlation for mass transfer coefficient of this cross-flow rotating packed bed was found to be:
Subjects
旋轉填充床
質傳
吸收
錯流
rotating packed bed
mass transfer, absorption
cr
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-93-R91524006-1.pdf
Size
23.53 KB
Format
Adobe PDF
Checksum
(MD5):61769805eec1ac999a88c33d144dd9fc