摘要:

AbstractThe R. S. Jane Memorial Lecture Award was established to commemorate the memory of the late Dr. Robert Stephen Jane who made an outstanding contribution to the chemical profession and the chemical industry in Canada. It is presented to a resident of Canada for exceptional achievement in the field of chemical engineering or industrial chemistry. The Lecture is presented at the annual C.I.C. Canadian Chemical Engineering Conference. Mr. Renzoni, recipient for 1968, presented this paper at the 1968 Tripartite Chemical Engineering Conference, September 22–25, 1968, in Montreal, Quebe

ISSN:0008-4034    

DOI:10.1002/cjce.5450470101

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1969

数据来源: WILEY

摘要:

AbstractExperiments concerned with the rate of fall of two prolate spheroids (needle‐like objects) in close proximity to each other are described in this paper. Quantitative agreement with S. Wakiya's theoretical predictions is obtained for the case in which two prolate spheroids are settling, one above the other, in the direction perpendicular to their axis of symmetry and for the case in which two prolate spheroids are settling end to end in the same horizontal plane in the direction perpendicular to their axis of symmetry.These experiments and this theoretical treatment apply only in the creeping motion region. At higher velocities, inertial effects would become significan

ISSN:0008-4034    

DOI:10.1002/cjce.5450470102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1969

数据来源: WILEY

摘要:

AbstractExperimental results are given which show that for non‐continuum conditions for heat conduction between a solid surface and a gas, there is a surface zone (of probably four or five mean free paths in thickness) where the “effective” thermal conductivity gradually changes from a value governed by gas — solid wall interactions to the normal continuum value in the bulk phase. In the temperature‐jump range, the effect of this surface zone in steady‐state situations can be adequately expressed by a temperature‐jump distance, but this approach is inadequate for transient state situations. In the transient state, a theory is required which allows for the gradually changing effective thermal conductivity in the

ISSN:0008-4034    

DOI:10.1002/cjce.5450470103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1969

数据来源: WILEY

摘要:

AbstractHeat and mass transfer rates from a vertical plate are reported for combined free and forced convection. Heat transfer coefficients were obtained from temperature gradients at the wall and mass transfer rates from thickness decrease measurements of naphthalene coatings.The free convection data cover a Grashof number range from 100 to 2 × 108and the combined flow parametersGr/Re2andGr'/Re2vary from 0.2 to 100 and 2 × 10−8to 3.25, respectively. Predictions from boundary layer solutions are in good agreement with the data.Absorption of ultraviolet light by naphthalene vapor was used to measure free convection concentration profiles. Results prove the versatility of this met

ISSN:0008-4034    

DOI:10.1002/cjce.5450470104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1969

数据来源: WILEY

摘要:

AbstractA study of the simultaneous heat and mass transfer from a single sphere to a turbulent air stream has been made. The aim of the investigation is to evaluate the effect of mass transfer on the rate of heat transfer. Results are compared with pure heat transfer data under similar conditions as well as those obtained by the evaporation of liquids from porous spheres.

ISSN:0008-4034    

DOI:10.1002/cjce.5450470105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1969

数据来源: WILEY

摘要:

AbstractA comparative study on the experimental techniques which have been used for the study of mass transfer from single gas bubble was made. The instantaneous mass transfer rates from a single carbon dioxide bubble rising through quiescent liquid medium (water) were measured using two different methods. For the first method, two movie cameras were placed on a moving platform along perpendicular directions and were used to record the position and size change of the bubble. The second method measured the mass transfer rates by recording the pressure changes in the free space at top of the bubble column, which was caused by the change of bubble size. The instantaneous mass transfer coefficients determined by either method exhibited wide scattering which is typical of work of this kind. Discussions are given on the relative merits of these two methods.

ISSN:0008-4034    

DOI:10.1002/cjce.5450470106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1969

数据来源: WILEY

摘要:

AbstractMass transfer in liquid‐liquid dispersions in a turbulent flow field has been investigated for the particular case where the overall process rate is governed by the diffusional resistance in the dispersed phase. Experiments with the system water‐iodine‐carbon tetrachloride have shown that the transfer mechanism in this case is similar to that for single drops at high Reynolds numbers. The results obtained show that the so‐called correlation factorRdepends strongly on the turbulence of the system. This relationship can be expressed asR ˜ R2, which is valid for the mass transfer rate both in turbulent liquid‐liquid dispersions and for some cases of solute diffusion in single oscilla

ISSN:0008-4034    

DOI:10.1002/cjce.5450470107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1969

数据来源: WILEY

摘要:

AbstractThe catalytic air oxidation of propylene to acrolein over a supported copper oxide catalyst was investigated in a continuous stirred vessel reactor between 375° and 450°C at atmospheric pressure. The effect of temperature, ratio of oxygen to propylene in feed and total feed rate (or contact time) on the conversion of propylene and the yield of acrolein were determined. It was found that with an increase in temperature, ratio of oxygen to propylene and contact time, the yield drops considerably though conversion increases.A study of the mixing characteristics of the stirred vessel reactor was carried out by following the conversion at various stirrer speeds.The kinetic data obtained were tested to determine the most probable model by the Hougen‐Watson method. The model that satisfactorily correlated the data describes the rate‐controlling step as the surface reaction occurring between adsorbed propylene, a vacant site and oxygen in the gas phase. The following Hougen‐Watson type rate equation has been proposed\documentclass{article}\pagestyle{empty}\begin{document} r = \frac{{aK_{{\rm C}3} {\rm H}_6 P_{{\rm C}_3 {\rm H}_6 {\rm P}_{{\rm O}_{\rm 2} } } }}{{(1 + K_{{\rm C}_3 {\rm H}_6 } P_{{\rm C}_3 {\rm H}_6 } + {\rm K}_{{\rm C}_3 {\rm H}_4 {\rm O}} P_{{\rm C}_3 {\rm H}_4 {\rm O}})^2 }} \end{document}The constants in the rate equation have been expressed as a function of temp

ISSN:0008-4034    

DOI:10.1002/cjce.5450470108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1969

数据来源: WILEY

摘要:

AbstractStabilization of a bed of dielectric particles against fluidization by an electric field (≥ 103volts/cm) is described. Glass bead and silica gel particle beds have been observed to behave as packed beds with flow rates (and pressure drops) of the fluidizing gas up to 15 times the normal incipient fluidization rate. The pressure drop at the breakup of this fixed bed was dependent on the second power of voltage, the particular bed material, and geometry of the system. Under suitable conditions 100% bed expansion without diffusive particle motion or bubble formation was obtained using silica gel particles. Comparison with iron particle bed‐magnetic field effects are presented. Surface polarization charge effects are the simplest explanation of the phenomena. Several of the possible applications are suggested, such as precipitation enhancement in an aerosol filter or as a new tool for investigating aggregative fluidizat

ISSN:0008-4034    

DOI:10.1002/cjce.5450470109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1969

数据来源: WILEY

摘要:

AbstractPrediction of single component adsorption in a packed bed operated isothermally is accomplished through the use of a mathematical model. The model accounts for the diffusional resistance between the bulk gas and the surface of the adsorbent particles, and for the diffusional resistance within the particles. The adsorption reaction within the pores is assumed to be very rapid compared to these two rate controlling mechanisms. The model can be used for isotherms of any shape and for gaseous feeds of any concentration. The partial differential equations of the model were solved numerically. Breakthrough curves are presented for four different isotherms and for two feed concentrations. The extension of the model to handle surface diffusion is treated. The model is compared with that of Rosen ≥11, 20and the differences are discusse

ISSN:0008-4034    

DOI:10.1002/cjce.5450470110

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1969

数据来源: WILEY