收稿日期: 2015-05-15
修回日期: 2015-06-23
网络出版日期: 2015-11-16
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
Received date: 2015-05-15
Revised date: 2015-06-23
Online published: 2015-11-16
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。
曹俊雅 , 马斌 , 李向阳 , 杨超 , 毛在砂 , 张广积 . 测定气—液—固搅拌槽内相含率分布取样法的改进[J]. 黄金科学技术, 2015 , 23(4) : 80 -85 . DOI: 10.11872/j.issn.1005-2518.2015.04.080
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.
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