測量加裝擋板之葉片式旋轉填充床之有效界面積

Determination of the effective interfacial area in blade-packing rotating packed bed with baffles

蔡靜誼(Ching-Yi Tsai)

指導教授 ： 陳昱劭

中原大學/工學院/化學工程研究所/碩士(2013年)

https://doi.org/10.6840/cycu201300878

摘要

本研究主要利用化學吸收二氧化碳之方法針對加裝擋板之葉片式旋轉填充床之有效質傳界面積（a）及去除率（E）進行研究以及利用氣提水中溶氧實驗獲得系統之總體積液膜質傳係數（kLa），並且將實驗值與宋（2011）對同樣系統進行揮發性有機物吸收獲得之總體積氣膜質傳係數（KGa）套入雙膜理論中計算，即可獲得kGa、kG及kL之數據，並探討操作參數，如轉速、液體流率、氣體流率、擋板有無以及填充物型式之影響，我們便可以藉此判斷葉片式加裝擋板系統之KGa值提升之主因。
由實驗結果得知，二氧化碳去除率與液體流率及轉速成正比，與氣體流率成反比，且加裝擋板可提升去除率；kLa及a會與轉速及液體流率成正比；kGa會與氣體流率、液體流率及轉速成正比；kG受氣體流率之影響較為明顯，與轉速無相關性；kL則是與液體流率及轉速成正比，並且可歸納出葉片式加裝擋板系統有高的質傳效能之原因為kG和有效質傳界面積之提升。另外，環形填充物之kGa、kLa、kL及a較葉片式填充物高。
最後，將加裝擋板之葉片式旋轉填充床之kLa、kGa、kG、kL及a實驗值作迴歸，所得知迴歸式可合理預測不同操作條件下加裝擋板之葉片式旋轉填充床之質傳係數。

關鍵字

旋轉填充床 ； 二氧化碳 ； 有效質傳界面積

並列摘要

In this works, we used chemical absorption of CO2 to measure the effective gas-liquid interfacial area (a) and used the stripping of dissolved oxygen to measure the volumetric liquid-side mass transfer coefficient (kLa) in blade packing rotating packed bed equipped with baffles. By substituting the overall volumetric gas-side mass transfer coefficient (KGa) from our previous work (Sung, 2011) and the experimental data from this study into the two-film theory, the volumetric gas-side mass transfer coefficient (kGa)、gas-side mass transfer coefficient (kG) and liquid-side mass transfer coefficient (kL) were obtained. The influence of operation conditions, such as gas flow rate, liquid flow rate, rotational speed, existence of baffles and packing types on mass transfer coefficients and effective gas-liquid interfacial area were investigated to figure out the reason for KGa enhancement in blade packing rotating packed bed equipped with baffles.
From the results, the removal efficiency of carbon dioxide was proportional to the liquid flow rate and the rotational speed. Conversely, it decreased with the increasing of gas flow rate. In addition, it was possible to increase the removal efficiency by adding the baffles. According to the experimental results, the mass transfer characteristics of the blade-packing RPB with baffles are: (1) kLa and a were proportional to liquid flow rate and rotational speed, (2) kGa was proportional to gas flow rate, liquid flow rate and rotational speed, (3) kG was affected by gas flow rate obviously, but unrelated to rotational speed, (4) kL was proportional to liquid flow rate and rotational speed. Furthermore, it is found that adding stationary baffles will enhance both of the kG and a.
Finally, based on the experimental results, correlations for kLa, kGa, kG, kL and a were developed. These correlations are valid under different operation conditions in blade packing rotating packed bed equipped with baffles.

並列關鍵字

effective interfacial area ； rotating packed bed ； carbon dioxide

參考文獻

宋威德，加裝擋板之葉片式旋轉填充床特性之研究，中原大學化學工程學系碩士學位論文，中壢 （2011）

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