以超重力技術氣提非牛頓流體中的揮發性有機物

Stripping of Volatile Organic Compounds in Non-Newtonian Fluids by Higee Technology

吳佳玲(CHIA-LING WU)

指導教授 ： 陳昱劭

中原大學/工學院/化學工程學系/碩士(2022年)

https://doi.org/10.6840/cycu202201458

摘要

旋轉填充床(rotating packed bed, RPB)是製程強化的設備之一，能利用離心力場產生比傳統填充塔高出幾百倍的質傳效率，是製程強化的關鍵。在文獻中有許多對於黏性流體在RPB中質傳係數影響的相關研究，但大部分都是針對牛頓流體進行探討，比較少針對非牛頓流體的質傳特性進行研究，因此本研究的目的在於探討非牛頓流體的質傳特性，使用旋轉填充床氣提羧甲基纖維素(Carboxymethyl Cellulose Sodium Salt, CMC)水溶液中的丙酮，探討RPB轉速、氣體流率、液體流率、CMC水溶液濃度對丙酮移除率(E)和總括氣膜質傳速率(KGa)的影響。

實驗結果顯示，CMC水溶液的黏度會隨轉速增加而下降，尤其在1.0 wt% CMC時更明顯，轉速從500 rpm提升至2000 rpm時，黏度可降低約14% (20 cp)。在RPB氣提丙酮程序中，黏度對丙酮移除率和總括氣膜質傳速率的影響很小，且丙酮移除率和總括氣膜質傳速率不會隨著CMC濃度增加而下降。丙酮移除率隨轉速增加、氣體流率增加而上升，隨液體流率增加而下降，最佳丙酮移除率可達到62.38%，為0.6 wt% CMC在轉速2000 rpm，氣體流率70 NL/min，液體流率100 ml/min；總括氣膜質傳速率會隨轉速增加、氣體流率增加、液體流率增加而上升，最佳總括氣膜質傳速率可達到9.36 s-1為0.6 wt% CMC在轉速2000 rpm，氣體流率70 NL/min，液體流率300 ml/min。

將KGa的實驗值與計算值比較後可以發現實驗值的KGa確實比填充塔的KGa計算值高很多，尤其是高黏度流體時，代表在高黏度流體下使用RPB進行氣提可以有更好的質傳效率。

關鍵字

超重力 ； 氣提 ； 非牛頓流體

並列摘要

Rotating packed bed (RPB) is a potential equipment in process intensification. It can utilize high centrifugal force to enhance mass transfer efficiency, which is the key to process intensification. There are many studies on the influence of viscous fluids on the mass transfer coefficient in RPBs in the literature, but most of them are for Newtonian fluids, and less for the mass transfer characteristics of non-Newtonian fluids. Therefore, the purpose of this study is to investigate the mass transfer characteristics of non-Newtonian fluids. A rotating packed bed was used to strip acetone in Carboxymethyl Cellulose Sodium Salt (CMC) solution. The operating variables are rotational speed, gas flow rate, liquid flow rate, and concentration of CMC solution to investigate the effects on acetone removal efficiency (E) and overall gas-film mass transfer coefficient (KGa).

The experimental results show that the viscosity of CMC solution will decrease with the increase of rotational speed, especially at 1.0 wt% CMC. When the rotation speed is increased from 500 rpm to 2000 rpm, the viscosity can be reduced by 14% (20 cp). In RPB, the viscosity has little effect on the acetone removal efficiency and the overall gas-film mass transfer coefficient . As the rotational speed and gas flow rate increased, the acetone removal rate increased; the liquid flow rate increased, the acetone removal rate decreased. The best acetone removal efficiency can reach 62.38% when using 0.6 wt% CMC at rotational speed 2000rpm, gas flow rate 70 NL/min and liquid flow rate 100ml/min. When the rotational speed, gas flow rate, and liquid flow rate increased, the overall gas-film mass transfer coefficient increased. The best overall gas-film mass transfer coefficient can reach 9.36 s-1 when using 0.6 wt% CMC at rotational speed 2000 rpm, gas flow rate 70 NL/min, and liquid flow rate 300 ml/min.

After comparing the experimental value of KGa with the calculated value, it can be found that the KGa of the experimental value is higher than the calculated value of KGa of the packed column, especially in the case of high viscosity fluids. This means that stripping with RPB in high viscosity fluids can have better mass transfer efficiency.

並列關鍵字

HIGEE ； Stripping ； Non-Newtonian Fluids

參考文獻

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