Perspective to study on macro-mixing in chemical reactors

doi:10.11949/j.issn.0438-1157.20150628

Abstract

Abstract:

Macro-mixing is an important unit operation in many process industries, and traditionally it is characterized with sort of mixing time. After academic and applied research of about 50 years, huge amount of data and knowledge has been accumulated from theoretical and experimental studies by chemical engineering community. Nevertheless, a strong sense of subjectivity is embedded in the definition of macro-mixing time and the relevant methods of experimental measurement, and the approach based on point-wise injection of tracer and point-wise detection fails to quantify the global behavior of mixing in the whole reactor. In this review, a few important topics related to the nature, definition and measurement of macro-mixing are scrutinized, the hidden defects are unveiled, and some worthwhile topics and useful suggestions are proposed to promote better thorough research on macro-mixing in single-phase and multiphase chemical reactors.

Key words: multiphase reactor, residence time distribution, mixing, macro-mixing, stirred tank

摘要：

宏观混合是过程工业中的一个重要单元操作,习惯上用混合时间来定量描述,半个世纪以来实验和理论研究的积累十分丰富。然而,目前宏观混合时间的定义和测量方法仍有很强的主观性,结果不能科学地反映化学反应器内宏观混合过程的全局。对宏观混合的几个重要问题进行了分析,指出其缺陷,并建议了今后进一步深入研究的方向和提升本领域研究科学性的措施。

关键词: 多相反应器, 停留时间分布, 混合, 宏观混合, 搅拌槽

CLC Number:

TQ027.1

MAO Zaisha, YANG Chao. Perspective to study on macro-mixing in chemical reactors[J]. CIESC Journal, 2015, 66(8): 2795-2804.

毛在砂, 杨超. 化学反应器宏观混合研究展望[J]. 化工学报, 2015, 66(8): 2795-2804.

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