多相气升式环流反应器局部相含率和环流速度  

Local hydrodynamics in a two-and three-phase air-lift loop reactor

作　　者：李红星[1] 

机构地区：[1]中国电子工程设计院,北京100101

出　　处：《化工进展》2014年第A01期117-122,共6页Chemical Industry and Engineering Progress

摘　　要：气升式环流反应器流动特性研究大多都局限于流动参数的平均特性研究,涉及气-液-固系统流动特性的研究也较少。在200×2500mm气升式环流反应器内,实验研究了空气-水两相及空气-水-玻璃珠三相体系中局部气、固相含率以及浆(液)相环流特性等随操作条件以及液、固相物性的变化规律。结果表明:1两相体系导流筒中截面平均气含率轴向分布有局部极大值,而固体和乙醇的加入使得气含率轴向分布平缓;2两相体系循环液速在导流筒中呈径向抛物分布,在环隙分布较均匀,加入固体和乙醇后对循环速度分布和大小影响不大;3三相体系中导流筒内固含率沿轴向升高呈增大趋势,环隙内轴向分布均匀;导流筒内、外固含率径向分布均不均匀,以近壁处为大;加入乙醇后对固含率分布影响不大。Flow characteristics study of air lift loop reactor is mostly confined to the average characteristics of loop reactor flow parameter,and the flow characteristics study of gas liquid solid system also is less.In this paper,a φ200 × 2500mm airlift loop reactor （ALR） with air water or air water glass beads constituting the two phase or three phase systems,respectively,the effects of solid loading and liquid physical properties on local phase holdups,and slurry （liquid） circulation characteristics were systematically investigated.It is demonstrated by the present measurements that：①The axial distribution of cross section average gas holdup in air water systems shows a maximum at the middle part of the riser,while the addition of solids and ethanol make the distribution uniform; ②Liquid circulation velocity shows a parabolic profile at radial direction within the riser of a gas liquid system,and solid loading and ethanol addition have small effects on the distribution; ③The cross section average solid holdup increases from the bottom to the top of the riser,but the axial distribution of the solid holdup is uniform in the down comer.The radial distribution of the local solid holdup is non uniform in both the two sections.The addition of ethanol has a negligibly small effect on such distributions.

关 键 词：气升式环流反应器 气含率 循环浆速 径向分布 轴向分布 

分 类 号：TQ920.5[轻工技术与工程—发酵工程]