摘要:

AbstractAn experimental investigation has been made to evaluate the friction, acceleration, and hydrostatic pressure drops in two‐phase vertical crossflow across a horizontal tube bundle through the measurement of the void fraction and determination of the two‐phase friction multiplier. The void fractions were found to increase with increasing mass velocity for a fixed quality level. The two‐phase friction multiplier increased with increasing mass velocity for a fixed value of the Martinelli parameter in both slug and spray flow and decreased with increasing mass velocity in bubbly flows. The void fraction and two‐phase friction multiplier data were correlated and used to predict with very good results the total pressure drop occurring in simulated diabatic flow tests and in actual diabatic tests usin

ISSN:0001-1541    

DOI:10.1002/aic.690340112

出版商:American Institute of Chemical Engineers    

年代:1988

数据来源: WILEY

摘要:

AbstractThe oxygen bleaching of wood pulp takes place in a heterogeneous system involving oxygen (gas), water (liquid), and fiber (solid). Inconsistent effects of process variables (reaction temperature, alkali concentration, and oxygen pressure) on the overall oxygen delignification rate of wood pulp in various reacting systems have been reported in the literature.An apparent intrinsic reaction rate model, excluding the interphase mass transfer effects, has been developed based on oxygen bleaching experiments in an agitated and ultralow‐consistency (solids content) reactor. The apparent intrinsic reaction rate model shows a faster delignification rate than those reported in the literature. The degree of inadequate delignification observed in the literature data is likely to be caused by insufficient mass transfer of bleaching chemicals to fiber

ISSN:0001-1541    

DOI:10.1002/aic.690340113

出版商:American Institute of Chemical Engineers    

年代:1988

数据来源: WILEY

摘要:

AbstractA light‐extinction principle was used to measure the fall speeds of the interfaces that develop during gravity sedimentation of monodisperse, bidisperse, and tridisperse suspensions of noncolloidal particles with small particle Reynolds numbers in the semidilute total particle volume fraction range 0.0003 ⩽c0⩽ 0.15. For monodisperse suspensions, the hindered settling velocity of the interface at the top of the suspension was found to be well represented by the correlation of Richardson and Zaki, provided that the isolated particle fall speed was chosen by linear extrapolation of the data toc0= 0, with 90% confidence intervals on the exponent ofn= 5.0 ± 0.1. For dilute monodisperse, bidisperse, and tridisperse suspensions, the hindered settling velocities of the interfaces showed agreement within experimental uncertainty with the theory of Batchelor, which predicts that the settling velocity decreases linearly with increasing particle concentration and which is based upon pairwise particle intera

ISSN:0001-1541    

DOI:10.1002/aic.690340114

出版商:American Institute of Chemical Engineers    

年代:1988

数据来源: WILEY

摘要:

AbstractDifferential protein extractions were measured with two types of extractants: inverted micelles and two‐phase aqueous systems. The results show that hollow‐fiber extractions are substantially faster than those possible in conventional equipment. The extractions are not compromised by loading or flooding because the flows of extractant and raffinate are almost completely independent. Mass transfer coefficients inferred from the measurements both support and extend design equations for these contact

ISSN:0001-1541    

DOI:10.1002/aic.690340115

出版商:American Institute of Chemical Engineers    

年代:1988

数据来源: WILEY

ISSN:0001-1541    

DOI:10.1002/aic.690340116

出版商:American Institute of Chemical Engineers    

年代:1988

数据来源: WILEY

ISSN:0001-1541    

DOI:10.1002/aic.690340117

出版商:American Institute of Chemical Engineers    

年代:1988

数据来源: WILEY

ISSN:0001-1541    

DOI:10.1002/aic.690340118

出版商:American Institute of Chemical Engineers    

年代:1988

数据来源: WILEY

ISSN:0001-1541    

DOI:10.1002/aic.690340119

出版商:American Institute of Chemical Engineers    

年代:1988

数据来源: WILEY

ISSN:0001-1541    

DOI:10.1002/aic.690340120

出版商:American Institute of Chemical Engineers    

年代:1988

数据来源: WILEY

ISSN:0001-1541    

DOI:10.1002/aic.690340121

出版商:American Institute of Chemical Engineers    

年代:1988

数据来源: WILEY