用数值模拟方法分析混合和导流筒对搅拌槽中沉淀硫酸钡的影响

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用数值模拟方法分析混合和导流筒对搅拌槽中沉淀硫酸钡的影响

王正^a; 毛在砂^a; 杨超^a; 沈湘黔^b

^aInstitute of Process Engineering, Chinese Academy of Sciences, Beijing 100080, China ^b Changsha Research Institute of Mining and Metallurgy, Changsha 410012, China

收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2006-12-28 发布日期:2006-12-28
通讯作者: 王正

Computational fluid dynamics approach to the effect of mixing and draft tube on the precipitation of barium sulfate in a continuous stirred tank

WANG Zheng^a; MAO Zaisha^a; YANG Chao^a; SHEN Xiangqian^b

^a Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100080, China

^bChangsha Research Institute of Mining and Metallurgy, Changsha 410012, China

Received:1900-01-01 Revised:1900-01-01 Online:2006-12-28 Published:2006-12-28
Contact: WANG Zheng

摘要/Abstract

摘要： The effect of mixing on the precipitation of barium sulfate in a continuous stirred tank is simulated numerically with different feeding location, feed concentration, impeller speed and residence time through solving the standard momentum and mass transport equations in combination with the moment equations for crystal population balance. The numerical method was validated with the literature data. The simulation results including the distribution of the local supersaturation ratio distribution in the precipitator, mean crystal size and coefficient of variation under different operating conditions compared well with experimental data in the literature. The effect of the presence of a draft tube on precipitation were also investigated, and it is suggested that the installation of a draft tube increased the mean crystal size, in general agreement with experimental work in the literature.

关键词: mixing;precipitation;stirred tank;computational fluid dynamics (CFD);numerical simulation;supersaturation

Abstract: The effect of mixing on the precipitation of barium sulfate in a continuous stirred tank is simulated numerically with different feeding location, feed concentration, impeller speed and residence time through solving the standard momentum and mass transport equations in combination with the moment equations for crystal population balance. The numerical method was validated with the literature data. The simulation results including the distribution of the local supersaturation ratio distribution in the precipitator, mean crystal size and coefficient of variation under different operating conditions compared well with experimental data in the literature. The effect of the presence of a draft tube on precipitation were also investigated, and it is suggested that the installation of a draft tube increased the mean crystal size, in general agreement with experimental work in the literature.

Key words: mixing, precipitation, stirred tank, computational fluid dynamics (CFD), numerical simulation, supersaturation

王正, 毛在砂,杨超, 沈湘黔. 用数值模拟方法分析混合和导流筒对搅拌槽中沉淀硫酸钡的影响[J]. , DOI: .

WANGZheng,MAOZaisha,YANGChao, SHENXiangqian. Computational fluid dynamics approach to the effect of mixing and draft tube on the precipitation of barium sulfate in a continuous stirred tank[J]. , DOI: .

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