旋轉填充床壓降特性之研究

The Study of Pressure Drop Characteristic in Rotating Packed Bed

張語桓(Yu-Huan Chang)

指導教授 ： 陳昱劭

中原大學/工學院/化學工程研究所/碩士(2011年)

https://doi.org/10.6840/cycu201100593

摘要

本論文主要是探討旋轉填充床內壓降特性，壓降會受到氣體流量、液體流量、轉速、填充床體內外半徑、液體黏度及液體分佈器等操作參數的影響。從實驗結果得知，壓降會隨著氣體流量及轉速增加而上升，但是不會受到液體流量的影響。另外也發現壓降的結果在乾床時會大於濕床。此外，壓降會隨著填充床體的徑向厚度增加而下降。使用雙側管型液體分佈器相對於單直管型液體分佈器能夠有效降低系統內的壓降。最後，考慮以上的操作參數，針對本實驗系統提出壓降迴歸式。
另外，本研究也討論旋轉填充床內溢流現象，將本實驗溢流點結果帶入Sherwood correlation ( Sherwood et al., 1938)，發現Sherwood correlation高估了本研究所使用旋轉填充床的操作範圍。最後，以水及異丙醇系統，討論接近溢流點的質傳現象，當接近溢流點時，系統已趨不穩，且氣體出口有微量水花被帶出，不利於質傳。

關鍵字

溢流 ； 壓降 ； 旋轉填充床

並列摘要

In this study, a systematic investigation on the pressure drop was performed in a countercurrent-flow rotating packed bed packed. The pressure drop was measured as a function of gas flow rate, liquid flow rate, rotational speed, liquid viscosity, the inner and outer radii of the bed and the types of the liquid distributor. Results showed that the pressure drop increased with increasing gas flow rate and rotational speed, and was not significantly affected by liquid flow rate. The pressure drop in a dry bed was higher than that in an irrigated bed. The pressure drop decreased with increasing the radial depth of the bed. Compared with single-tube liquid distributor, using double-tube liquid distributor can reduce the pressure drop effectively. Considering all operation parameters that mentioned before, a new correlation of pressure drop was proposed.
Besides, the flooding phenomenon in rotating packed bed was also investigated in this study. Results showed that Sherwood correlation overestimated the operation range of rotating packed bed. The mass transfer near the flooding point was also investigated using water – isopropyl alcohol absorption system. When the system approaching flooding point, the system became unstable and a few liquid was carried out from gas outlet, and was not favorable for mass transfer.

並列關鍵字

pressure drop ； flooding ； rotating packed bed

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