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黄金科学技术 ›› 2015, Vol. 23 ›› Issue (4): 80-85.doi: 10.11872/j.issn.1005-2518.2015.04.080

• 冶炼技术与装备研发 • 上一篇    下一篇

测定气—液—固搅拌槽内相含率分布取样法的改进

曹俊雅1,马斌1,2,李向阳2*,杨超2,毛在砂2,张广积2   

  1. 1.中国矿业大学(北京)化学与环境工程学院,北京   100083;
    2.中国科学院过程工程研究所绿色过程与工程重点实验室,北京   100190
  • 收稿日期:2015-05-15 修回日期:2015-06-23 出版日期:2015-08-28 发布日期:2015-11-16
  • 通讯作者: 李向阳(1980-),男,河南焦作人,副研究员,从事多相反应器实验、数值模拟和测量仪器开发工作。 E-mail:xyli@ipe.ac.cn
  • 作者简介:曹俊雅(1981-),女,河南鲁山人,副教授,从事生物冶金研究工作。caojy@cumtb.edu.cn
  • 基金资助:

    国家自然科学基金项目“新型生物冶金测试反应器及气液固三相流测量仪器研制”(编号:21427814)、“气—液—固三相搅拌槽内颗粒群行为和反应模拟”(编号:21276004)、“微生物硫化浮选低品位氧化型镍矿界面作用研究”(编号:21306225)和国家高技术研究发展计划(863计划)“铅/铬亚熔盐清洁生产共性关键技术”(编号:2011AA060704)联合资助

The Improved Sampling Method for the Measurement of  Phase Holdup Distributions in Gas-Liquid-Solid Stirred Tank

CAO Junya1,MA Bin1,2,LI Xiangyang2,YANG Chao2,MAO Zaisha2,ZHANG Guangji2   

  1. 1.School of Chemical and Environmental Engineering,China University of Mining  Technology(Beijing),Beijing   100083,China;
    2.Key Laboratory of Green Process and Engineering,Institute of Process Engineering,Chinese Acadamy of Sciences,Beijing   100190,China
  • Received:2015-05-15 Revised:2015-06-23 Online:2015-08-28 Published:2015-11-16

摘要:

在化工冶金和环境保护等领域应用十分广泛的气—液—固三相搅拌槽反应器由于缺少基础实验数据造成设计放大的困难。对于能直接有效地反映反应器内部特性的分散相(气泡和固体颗粒)的局部相含率分布,目前仍然没有可靠的实验测量方法。在总结前人工作的基础上,设计了一种带喇叭口的取样管,并进行局部相含率的测量,验证了该取样管的可行性。当开口大小为取样管管径的3倍时测量结果最准确,开口朝下时更易收集气体。改进的取样法实现了对以空气为气相、水为液相、石英砂为固相的三相搅拌槽内局部相含率分布的测量。实验采用单层标准Rushton桨(RTD),通过实验数据分析发现:局部固含率由中心沿径向逐渐增大,由槽底向上则逐渐减小,而局部气含率则由中心沿径向减小,由槽底沿轴向分布较均匀,测定结果与对反应器的定性认识相符。

关键词: 三相搅拌槽, 取样法, 局部相含率, 轴径向分布

Abstract:

The gas-liquid-solid three-phase stirred tank reactor is widely applied in the chemical metallurgy and environment protection.The lack of basic experimental data makes it difficult to scale up a gas-liquid-solid three-phase stirred tank.The concentration distribution of the dispersed phases(bubbles and solid particles) can reflect the characteristics inside the reactor directly and effectively.There is still no reliable measurement technique to effectively reflect the characteristics of local phase holdup distribution inside the reactor.This paper reports a sampling tube with a bell mouth to measure the local holdup,and its feasibility is tested.The measurement is more accurate when opening size is 3d and it is more likely to collect gas when opening downwards.Improved sampling method is applied to measure the local phase holdup in the stirred tank with an air-water-quartz sand three-phase system.The experiments use single-layer Rushton disc turbine(RTD),analysis of these experimental data suggests:The local solid holdup increases in the radial direction while it decreases along the axial distance from the bottom to the top,the local gas holdup decreases in the radial direction,and it is relatively uniform in the axial direction.The present results are qualitatively in conformity with our comprehension of this kind of reactor.

Key words: three-phase stirred tank, sampling method, local phase holdup, radial and axial distribution

中图分类号: 

  • TQ027.2

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