摘要:

AbstractUntil recently, the subject of chemical process synthesis was largely ignored in the chemical engineering literature despite its importance in chemical engineering practice. However since 1968, attention to the subject has greatly increased and important progress has been made. This review article critically surveys the readily accessible literature in chemical process synthesis from two points of view: theory and applications. It is concluded that a number of effective synthesis tools are now available for application in industrial chemical process design. However, much more remains to be done, particularly with regard to the development of synthesis procedures which can lead to novel processing system structures.

ISSN:0001-1541    

DOI:10.1002/aic.690190103

出版商:American Institute of Chemical Engineers    

年代:1973

数据来源: WILEY

摘要:

AbstractTheoretical models for computing velocity profiles and friction factors for sinusoidally pulsing laminar flow in linearly elastic tubes were derived from the Navier‐Stokes equations, a modified Fanning equation, and the pressure‐tube wall movement relationship. The theoretical results were checked experimentally forNReand λ = ωR2/vvalues up to 2000 and 57, respectively. It was found that the theoretical friction factors predicted the experimental values to within less than 13%. Also the results showed that the energy losses in elastic tubes were greater than in rigid

ISSN:0001-1541    

DOI:10.1002/aic.690190104

出版商:American Institute of Chemical Engineers    

年代:1973

数据来源: WILEY

摘要:

AbstractThe object of this study was to derive a model which would accurately describe the evaporation of a multicomponent droplet, especially near its boiling point. The model is derived and is shown to have the following properties: the transport of one component can be augmented by the bulk (Stefan) flow of the other components, and the droplet can never exceed its boiling point, a property not realized by previous models. The ordinary differential equations which constitute the model were integrated numerically, and results are given for both two‐ and three‐component dropl

ISSN:0001-1541    

DOI:10.1002/aic.690190105

出版商:American Institute of Chemical Engineers    

年代:1973

数据来源: WILEY

摘要:

AbstractModels for unsteady water transport in fuel cell configurations of Bacon‐Pratt and Whitney type are derived. Tests with a specially constructed isothermal cell producing no water and order of magnitude analysis show that diffusion through the liquid alone cannot account for the observed behavior. An analytical solution which includes diffusion in both the liquid and the gas spaces of the matrix is in better agreement with the data than models which consider diffusion in either the liquid or in the gas phase alon

ISSN:0001-1541    

DOI:10.1002/aic.690190106

出版商:American Institute of Chemical Engineers    

年代:1973

数据来源: WILEY

摘要:

AbstractThe thermoelectrogravitational electrophoresis column without reservoirs has been conceived following the principle of the Clusius‐Dickel thermal diffusion column. The transport equation approach in thermal diffusion developed by Jones and Furry to explain the behavior of a conventional thermogravitational thermal diffusion column has been applied to describe the electrophoretic separation in the thermoelectrogravitational electrophoresis column. Equations have been established for a system in which one single or one hypothetically single component is mobile and the other species are at their isoelectric points.Theoretical calculations for the velocity profiles, temperature distribution, and the steady state batch separation factors have been made with field strength, temperature difference, membrane spacing, and electric mobility as variables, and expected trends of the results are discussed using the steady state solution of the transport equation for batch operatio

ISSN:0001-1541    

DOI:10.1002/aic.690190107

出版商:American Institute of Chemical Engineers    

年代:1973

数据来源: WILEY

摘要:

AbstractIn Part I of this paper, a thermoelectrogravitational electrophoresis column without reservoirs was proposed for preparative electrophoretic separations. The Furry, Jones, and Onsager procedure in thermal diffusion was applied to develop a transport equation, and its solution for the steady state batch case was employed to demonstrate some typical effects of temperature difference, electric field strength, and membrane spacing on the predicted steady state batch separation in the column.In this part, a theory is first developed from mathematical analysis of a continuous‐flow thermoelectrogravitational column without reservoirs by modification of the transport equation to take into account the bulk flow through the column.An experimental center‐fed thermoelectrogravitational electrophoresis column and the related equipment used to obtain experimental data to test the theory are described. Further, experimental separation factors as a function of flow rates ranging from 0 to 10 g/min for the bovine albumin system at twopH values (8.6 and 6.0) were obtained using two membrane spacings (0.1354 and 0.3018 cm respectively) at four different electric field strengths (0.0423 to 0.423 volt/cm) and for three different temperature differences of 0°C, 8.5°C, and 16°C. Experimental data indicated that meaningful separations could be obtained using thermoelectrogravitational columns but that the temperature difference has an adverse effect on electrophoretic separation.Analysis of the experimental flow data showed that theory and experiment are not in quantitative agreement. However, there was general, qualitative agreement between theory and experiment for the dependence of separation on field strength, temperature difference, membrane spacing and mobility of the com

ISSN:0001-1541    

DOI:10.1002/aic.690190108

出版商:American Institute of Chemical Engineers    

年代:1973

数据来源: WILEY

摘要:

AbstractA theory has been developed for the mathematical analysis of the transient behavior of a thermoelectrogravitational electrophoresis column without reservoirs using the transport equation approach. Experimental data were obtained with a parallel membrane batch electrophoresis column to test the theory.The transient batch separation factor data obtained for a bovine albumin system under different values of the parameters (electric field strength, mobility, membrane spacing, and temperature difference) are discussed and compared with the results obtained using column transport coefficients empirically determined from steady state flow data (see Part 11). Experimental separation factors for the transient operation agree with those predicted using column transport coefficients (H and K) derived from steady flow studies, providing further support for the use of the Furry, Jones, Onsager approach to the analysis of electrophoresis columns. Failure of quantitative agreement between theory and experiment is attributed to the use of large spacings in obtaining experimental data.

ISSN:0001-1541    

DOI:10.1002/aic.690190109

出版商:American Institute of Chemical Engineers    

年代:1973

数据来源: WILEY

摘要:

AbstractA new model for porous media comprised of monosized, or nearly monosized grains, is developed. In applying this model to a packed bed, the bed is assumed to consist of a series of statistically identical unit bed elements each of which in turn consists of a number of unit cells connected in parallel. Each unit cell resembles a piece of constricted tube with dimensions which are random variables. The problem of flow through each unit cell is reduced, subject to reasonable assumptions, to the determination of the flow in an infinitely long periodically constricted tube. The solution of this flow problem is given in a companion publication. This model, together with the solution of the flow through it, can be used for the modeling of processes which take place in the void space of a bed.As a preliminary test, theoretical friction factor values, based on the proposed model, were compared with experimental ones for two different beds and found to be in good agreement even in the region of high Reynolds numbers where the nonlinear inertia terms are significant.

ISSN:0001-1541    

DOI:10.1002/aic.690190110

出版商:American Institute of Chemical Engineers    

年代:1973

数据来源: WILEY

摘要:

AbstractA numerical method for the solution of the problem of steady state, incompressible Newtonian flow through periodically constricted tubes is developed. All terms of the Navier‐Stokes equation are retained, including the nonlinear inertia terms.Sample calculations for a uniform periodically constricted tube, the geometry of which is connected with the modeling of a packed bed of sand are given, including streamlines, axial and radial velocity profiles, pressure profiles, and the dimensionless pressure drop versus Reynolds number relation. The effect of some geometric characteristics of periodically constricted tubes on their friction factor is investigated numerically, and comparison of some existing experimental data with calculated ones is mad

ISSN:0001-1541    

DOI:10.1002/aic.690190111

出版商:American Institute of Chemical Engineers    

年代:1973

数据来源: WILEY

摘要:

AbstractTheoretical equations and graphs are presented for filter cake reslurrying and washing with linear solute sorption.In the case of washing, the filter cake was represented by a model consisting of a number of mixing cells in series. Due to the complexity of the model, explicit algebraic solutions could not be obtained for countercurrent washing, but numerical data were generated using a computer.Practical application of the above is outlined.

ISSN:0001-1541    

DOI:10.1002/aic.690190112

出版商:American Institute of Chemical Engineers    

年代:1973

数据来源: WILEY