Ozone Mass Transfer with Combined Effects of Ozone Decomposition and Reaction with Pollutants in a Semibatch Stirred Vessel

攪拌槽中包含有臭氧自解及其與污染物反應的質量傳送

邱浚祐(Chun-Yu Chiu) ； 張慶源(Ching-Yuan Chang) ； 陳奕宏(Yi-Hung Chen) ； 於幼華(Yue-Hwa Yu) ； 蔣本基(Pen-Chi Chiang) ； 顧洋(Young Ku)

《Journal of the Chinese Institute of Chemical Engineers》 34卷3期 (2003/05) Pp. 281-289

https://doi.org/10.6967/JCICE.200305.0281

摘要

本研究修改並延伸Anselmi et al. (1984, 1985)對於半批次氣-液攪拌槽所提出的數學模式，用來描述臭氧在水溶液中包含有吸收、臭氧自解及臭氧與污染物反應的質量傳送行為，且其中臭氧的自解速率式及臭氧與污染反應的速率式可以用任意階反應式來表示（即其反應級數不一定為整數）。模式中共有四個系統方程式來描述臭氧在溶液中的濃度(CALb)、污染物在溶液中的濃度(CBTLb)、臭氧在氣體滯留相中的濃度(CAGi)、及臭氧在液面上剩餘空間的濃度(CAGe)。同時模式中也考慮增進因子(Er)的影響。利用本模式可以計算Er和CALb與CBTLb的關係。此動態系統之Er、CALb和CBTLb在氣-液接觸裝置中均會隨接觸時間而改變。將本模式簡化後，模擬Anselmi et al. (1985)（苯磺酸與臭氧反應）和Beltran et al. (1990) （甲酚與臭氣反應）的實驗條件並與其實驗數據作比較，結果顯示均相當吻合。因此足以證明本模式的有效性。

並列摘要

The mathematical models for a semibatch stirred gas-liquid contactor proposed by Anselmi et al. (1984, 1985) are extended to described the mass transfer of ozone absorption, decomposition and reaction with pollutants in aqueous solution with the decomposition and reaction rate expressions of general reaction orders (not necessarily integers) taking into consideration the effects of ozone decomposition and reactions on absorption. Four system equations are employed to describe the ozone (A) concentrations in the bulk liquid (CALb), the hold-up gas (CAGi), and the outlet gas in the free volume above the liquid surface (CAGe), and the pollutant (B) concentration in the bulk liquid (CBTLb), respectively. The combined effects of ozone decomposition and reaction with pollutant on the mass transfer, which are reflected by the enhancement factor (Er) defined as the ratio of mass absorbed per unit area in time t with chemical reactions to that without chemical reactions or of the purely physical absorption, are considered in the refined model. Furthermore, the model also takes into account the variation of Er with CALb and CBTLb, which vary with time during the course of gas-liquid contacting. Comparison of the predicted values of concentrations of the proposed model in simplified from with the experimental data of Anselmi et al (1985) indicates good agreement. For ozonation systems with high reaction rates(for example, ozonation of o-cresol investigated by Beltran et al. (1990)), the enhancement factors are large and cause significant influence on the mass transfer of the ozone and pollutant.

並列關鍵字

Ozone ； Ozonation ； Mass transfer ； Enhancement factor