EFFECT OF UNFAVORABLE CONTINUOUS PHASE DENSITY GRADIENT ON AXIAL MIXING

被引:19
作者
HOLMES, TL
KARR, AE
BAIRD, MHI
机构
[1] MCMASTER UNIV,DEPT CHEM ENGN,HAMILTON L8S 4L7,ONTARIO,CANADA
[2] OTTO H YORK CO INC,PARSIPPANY,NJ 07054
关键词
D O I
10.1002/aic.690370306
中图分类号
TQ [化学工业];
学科分类号
0817 ;
摘要
Field experience with several industrial reciprocating plate liquid-liquid extraction columns indicated that large density gradients in the continuous phase resulted in excessive backmixing. Since there are no published data on the effect of higher density in the upper section compared to lower density in the bottom section of the column, experiments were performed with the calcium chloride brine-water system in a 76.2 mm diameter reciprocating plate column. Axial dispersion coefficients, E, were found to be 10-20 times higher than the values in systems with uniform densities. E decreased with increasing agitation to 30% of the value with no agitation. The effect of increasing flow rate of water up the column was to increase both E and the Peclet number. E was correlated with the density difference between any point in the column and tap water. Another correlation was obtained showing the effects of buoyant and mechanical energy input on axial dispersion.
引用
收藏
页码:360 / 366
页数:7
相关论文
共 14 条
[1]  
HAFEZ MM, 1978, T I CHEM ENG-LOND, V56, P229
[2]   FLOODING AND AXIAL-DISPERSION IN RECIPROCATING PLATE EXTRACTION COLUMNS [J].
HAFEZ, MM ;
BAIRD, MHI ;
NIRDOSH, I .
CANADIAN JOURNAL OF CHEMICAL ENGINEERING, 1979, 57 (02) :150-158
[3]   A COMPARISON OF DIFFERENTIAL AND STAGEWISE COUNTER CURRENT EXTRACTION WITH BACKMIXING [J].
HARTLAND, S ;
MECKLENB.JC .
CHEMICAL ENGINEERING SCIENCE, 1966, 21 (12) :1209-&
[4]   PERFORMANCE OF A RECIPROCATING-PLATE EXTRACTION COLUMN [J].
KARR, AE .
AICHE JOURNAL, 1959, 5 (04) :446-452
[5]   AXIAL MIXING AND SCALEUP OF RECIPROCATING PLATE COLUMNS [J].
KARR, AE ;
RAMANUJAM, S ;
LO, TC ;
BAIRD, MHI .
CANADIAN JOURNAL OF CHEMICAL ENGINEERING, 1987, 65 (03) :373-381
[6]  
KARR AE, 1971, P INT SOLVENT EXTN C, P299
[7]  
KARR AE, 1979, P INT SOLVENT EXTN C, V1, P355
[8]   AXIAL-DISPERSION IN A RECIPROCATING PLATE EXTRACTION COLUMN [J].
KIM, SD ;
BAIRD, MHI .
CANADIAN JOURNAL OF CHEMICAL ENGINEERING, 1976, 54 (1-2) :81-89
[9]   LONGITUDINAL MIXING IN A ... PULSED SIEVE-PLATE EXTRACTION COLUMN [J].
MAR, BW ;
BABB, AL .
INDUSTRIAL AND ENGINEERING CHEMISTRY, 1959, 51 (09) :1011-1014
[10]   LONGITUDINAL DISPERSION IN 2-PHASE CONTINUOUS-FLOW OPERATIONS [J].
MIYAUCHI, T ;
VERMEULEN, T .
INDUSTRIAL & ENGINEERING CHEMISTRY FUNDAMENTALS, 1963, 2 (02) :113-&