Understanding gas-phase hydrodynamics in bubble columns: A convective model based on kinetic theory

被引:80
作者
Hyndman, CL [1 ]
Larachi, F [1 ]
Guy, C [1 ]
机构
[1] ECOLE POLYTECH,DEPT CHEM ENGN,MONTREAL,PQ H3C 3A7,CANADA
关键词
bubble columns; hydrodynamics; disengagement; kinetic theory;
D O I
10.1016/S0009-2509(96)00387-9
中图分类号
TQ [化学工业];
学科分类号
0817 ;
摘要
Bubble column hydrodynamics exhibit a bubbly flow regime at low superficial gas velocity and a churn turbulent regime at higher superficial gas velocity, except in small diameter columns where slugging is observed. ii convective model developed previously is compared to dynamic gas disengagement (DGD) data. Theoretical disengagement curves calculated from the convective model bubble velocity distribution (at steady state) compare well to DGD curves at the transition point. Our analysis of DGD curves using the convective model indicates that in the churn turbulent regime, gas hold-up consists of a superposition of large bubbles on a transition point bubble velocity distribution. A kinetic model for gas-phase hydrodynamics capable of describing both the bubbly and churn turbulent flow regimes is proposed. Absolute bubble velocity distributions are calculated based on an ideal bubble velocity distribution and rules of bubble-bubble interaction. A transition zone is predicted by the model. Overall gas hold-up is predicted in the bubbly and churn turbulent flow regimes and the fraction of gas hold-up in the form of large bubbles is determined in the churn turbulent flow regime. The transition zone is in agreement with the literature and the large bubble fraction in the churn turbulent flow regime is well predicted by the model. Copyright (C) 1996 Elsevier Science Ltd
引用
收藏
页码:63 / 77
页数:15
相关论文
共 40 条
[1]   EFFECT OF MEASUREMENT METHOD ON THE VELOCITIES USED TO DEMARCATE THE ONSET OF TURBULENT FLUIDIZATION [J].
BI, HT ;
GRACE, JR .
CHEMICAL ENGINEERING JOURNAL AND THE BIOCHEMICAL ENGINEERING JOURNAL, 1995, 57 (03) :261-271
[2]  
BRERETON CMH, 1992, CHEM ENG RES DES, V70, P246
[3]   CHARACTERIZATION OF THE FLOW TRANSITION BETWEEN BUBBLING AND TURBULENT FLUIDIZATION [J].
CHEHBOUNI, A ;
CHAOUKI, J ;
GUY, C ;
KLVANA, D .
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 1994, 33 (08) :1889-1896
[4]   FLOW STRUCTURE IN A 3-DIMENSIONAL BUBBLE-COLUMN AND 3-PHASE FLUIDIZED-BED [J].
CHEN, RC ;
REESE, J ;
FAN, LS .
AICHE JOURNAL, 1994, 40 (07) :1093-1104
[5]   MEASUREMENT OF GAS HOLDUPS AND SAUTER MEAN BUBBLE DIAMETERS IN BUBBLE COLUMN REACTORS BY DYNAMIC GAS DISENGAGEMENT METHOD [J].
DALY, JG ;
PATEL, SA ;
BUKUR, DB .
CHEMICAL ENGINEERING SCIENCE, 1992, 47 (13-14) :3647-3654
[6]   IMPROVED TOOLS FOR BUBBLE COLUMN REACTOR DESIGN AND SCALE-UP [J].
DECKWER, WD ;
SCHUMPE, A .
CHEMICAL ENGINEERING SCIENCE, 1993, 48 (05) :889-911
[7]  
DECKWER WD, 1992, BUBBLE COLUMN REACTO, P171
[8]   DIAGNOSTICS OF GAS-LIQUID FLOW PATTERNS IN CHEMICAL-ENGINEERING SYSTEMS [J].
DRAHOS, J ;
CERMAK, J .
CHEMICAL ENGINEERING AND PROCESSING-PROCESS INTENSIFICATION, 1989, 26 (02) :147-164
[9]   FRACTAL BEHAVIOR OF PRESSURE-FLUCTUATIONS IN A BUBBLE COLUMN [J].
DRAHOS, J ;
BRADKA, F ;
PUNCOCHAR, M .
CHEMICAL ENGINEERING SCIENCE, 1992, 47 (15-16) :4069-4075
[10]   EFFECT OF OPERATING-CONDITIONS ON THE CHARACTERISTICS OF PRESSURE-FLUCTUATIONS IN A BUBBLE COLUMN [J].
DRAHOS, J ;
ZAHRADNIK, J ;
PUNCOCHAR, M ;
FIALOVA, M ;
BRADKA, F .
CHEMICAL ENGINEERING AND PROCESSING-PROCESS INTENSIFICATION, 1991, 29 (02) :107-115