二级环流反应器中收缩-膨胀隔板的性能优化

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摘要通过在二级环流反应器两级之间安装具有收缩-膨胀形状的隔板,可以有效减小两级之间的液相回流流量,但同时会增加流体流动阻力。为了在减小液相回流流量的前提下减小流动阻力,本研究对隔板进行优化设计。首先通过模拟计算获得不同隔板下的压降和液相回流流量,随后对数据进行拟合,得到压降、液相回流流量与结构参数的关联式。计算结果表明当表观气速较小时,隔板宽度对压降影响较大,高度的影响较小。表观气速增大时,隔板高度对压降的影响变大。在所有气速下,隔板宽度是影响液相回流流量的决定因素。最后通过多目标优化,获得了在不同表观气速下最优隔板的Pareto前沿。

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	卢哲
	史嘉帧
	郭凯
	刘春江
	郑龙云

关键词：收缩-膨胀隔板优化二级气升式环流反应器气液两相流计算流体力学

Abstract： Loop reactors are widely applied in industries because of good characteristics of gas-liquid interaction, and a series of internals are developed and equipped with the reactor to further reinforce the interaction. The installation of a contraction-expansion partition between two stages in a two-stage airlift loop reactor can effectively reduce the reversed liquid flow between the stages, while it increases the flow resistance. To pinpoint the effect of width and height of the partition on flow dynamics and obtain the partition which can reduce the flow resistance while decrease the reversed liquid flow, this study conducts an optimization of the partition utilizing CFD-PBM and multi-objective optimization methods. Firstly, a series of numerical simulation-based experiments with various partitions at three different superficial gas velocities are conducted to obtain the pressure drop and the reversed liquid flow in the two-stage loop reactor. It is found that the width and height of the partition as well as superficial gas velocities lead to different performance of flow dynamics. The width has a greater effect on pressure drop than the height at a low superficial gas velocity, while the effect of height on the pressure drop becomes larger as the superficial gas velocity increases and width is the determinant factor for the reversed liquid flow at all superficial gas velocities in the study. The correlations for pressure drop and the reversed liquid flow with the width and height of the partition are obtained by data fitting. The Pareto fronts for the structure of partition at various superficial gas velocities are obtained using multi-objective optimization with the pressure drop and the reversed liquid flow as the optimization objectives and the width and height of the partition as optimization parameters.

Keywords： contraction-expansion partition optimization two-stage airlift loop reactor gas-liquid flow computational fluid dynamics

Received 2022-02-05;

Fund:国家自然科学基金项目(21706182;21706187)。

Corresponding Authors: 郭凯,讲师,E-mail:guokaitianjin@163.com。 Email: guokaitianjin@163.com

About author: 卢哲(1994-),男,硕士研究生,现从事化学工程方面的研究。

引用本文:

卢哲, 史嘉帧, 郭凯, 刘春江, 郑龙云.二级环流反应器中收缩-膨胀隔板的性能优化[J]. 化学工业与工程, 2024,41(1): 125-135

LU Zhe, SHI Jiazhen, GUO Kai, LIU Chunjiang, ZHENG Longyun.Optimization of contraction-expansion partition in a two-stage internal airlift loop reactor[J]. Chemcial Industry and Engineering, 2024,41(1): 125-135

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