内循环气升式反应器的操作特性与流体力学研究

摘要气升式反应器在化工和环境等领域有着广泛的应用,准确预测反应器内气液两相流动与传质行为对于反应器的设计与放大十分重要。论文通过建立稳态条件下内循环气升式反应器内的气液两相流动模型,实现对循环液速v_L、气含率ε_G与气相循环比β等重要流体力学参数的求解。当提升管高度分别为2和6 m时,模型参数c₀取0.65,模型计算的反应器内的v_L与ε_G值与实验结果的相对平均误差小于6.2%。在此基础上,进一步考察了提升管高度H对平均循环液速和平均气含率的影响规律。模拟结果表明,随着提升管高度的增加,循环推动力增加,循环液速上升,平均气含率略有下降。下降管和提升管内气含率比α与反应器尺寸和表观气速等操作条件相关,取值范围为0.72~0.80。

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	李亮
	靳晓霞
	付春明
	张成凯
	郝润秋

关键词：气升式反应器稳态模拟气相循环比循环液速气含率

Abstract： Air-lift reactors are widely used in the field of chemical and environment engineering, and it is of vital significance to accurately predict air-liquid two phase circulation and mass transfer behavior. In this study, a gas-liquid two phase flow model of internal loop air-lift reactor under steady state was proposed to calculate a series of fluid dynamic parameters, including circulation velocity v_L, gas holdup ε_G, and ratio of gas circulation β. Circulation velocity v _L and gas holdup ε_G was obtained via experiments in risers of 2 m and 6 m long and when the model parameter c₀ was 0.65, the relative average error between model calculation and experimental results for v_L and ε_G was less than 6.2%. The influence law of riser height on liquid circulation velocity and gas holdup was investigated. The results showed that with the increase of riser height, the circulating driving force increases, the circulating liquid velocity increased, and the average gas holdup decreased slightly. It was found that the ratio of gas holdup in the downcomer and riser related to operation parameters, such as reactor’s size an apparent gas velocity, and varied between 0.72 and 0.80.

Keywords： airlift reactor steady-state simulation gas phase circulation ratio circulation liquid velocity gas holdup

Received 2022-11-06;

Fund:重大科技项目(NOOC-KJ 145 FZDXM 00 TJY 003 TJY 2021)。

Corresponding Authors: 李亮,高级工程师,E-mail:liliang80cn@163.com。 Email: liliang80cn@163.com

About author: 李亮(1980-),男,高级工程师,现从事工业废水处理方面的研究。

引用本文:

李亮, 靳晓霞, 付春明, 张成凯, 郝润秋.内循环气升式反应器的操作特性与流体力学研究[J]. 化学工业与工程, 2024,41(3): 135-141

LI Liang, JIN Xiaoxia, FU Chunming, ZHANG Chengkai, HAO Runqiu.Study on operation characteristics and fluid dynamics of internal loop air-lift reactor[J]. Chemcial Industry and Engineering, 2024,41(3): 135-141

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