摘要:

AbstractThe objective of this study is to develop a model and correlate it with experimental measurements for predicting the tolerable degree of supersaturation of gas‐water solutions. This model is also capable of predicting quite accurately the cavitation phenomenon in wate

ISSN:0001-1541    

DOI:10.1002/aic.690310902

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractSteady state experiments and their interpretation were performed to explore the kinetics of CO oxidation over a supported Co3O4catalyst. The rate of reaction was found to depend on temperature and the partial pressure of oxygen but not on the partial pressure of carbon monoxide. It is shown that catalyst dynamics must be accounted for to achieve real understanding.

ISSN:0001-1541    

DOI:10.1002/aic.690310903

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractThe transient responses of a fixed‐bed reactor to step increases and decreases in CO, O2, and/or CO2feed concentrations were measured and interpreted. It is shown that dynamic methods yield vastly more phenomenological and mechanistic information than steady state measurements, with significantly less experimental effor

ISSN:0001-1541    

DOI:10.1002/aic.690310904

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractInterpretations of a variety of transient experiments are combined with information from the literature to reveal the roles played by the Co3O4catalyst surface and adsorbed species. The reaction path depends on the oxidation state of the catalyst. A rather coherent picture of oxidation‐reduction catalysis by a metal oxide is obtaine

ISSN:0001-1541    

DOI:10.1002/aic.690310905

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractAn hypothesis is proposed to explain the origin of short‐lived sites observed in nucleate pool boiling. Conditions are postulated under which microbubbles might circulate into the superheated liquid region and serve as the source of these nucleation sites. Consequences of this possible mechanism are examined for explanations of hysteresis effects and scatter of results in boiling researc

ISSN:0001-1541    

DOI:10.1002/aic.690310906

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractThe method of integral relations is used to derive a nonlinear two‐wave equation for long waves on the surface of vertical falling liquid films. This equation is valid within a range of moderate Reynolds numbers and and be reduced in some cases to other well‐known equations.The theoretical results for the fastest growing waves are compared with the experimental results concerning velocities, wave numbers, and growth rates of the waves in the inception region. The validity of the theoretical assumptions is also confirmed by direct measurements of instantaneous velocity profiles in a wave liquid film.The results of the experimental investigation concerning nonlinear stationary waves and the evolution of initial solitary disturbances are presen

ISSN:0001-1541    

DOI:10.1002/aic.690310907

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractIn this paper the problem of distillation sequence synthesis with heat integration is formulated and solved as a mixed integer linear superstructure optimization problem. Allowing both conventional and multieffect distillation, two alternatives for generating a superstructure are shown, then a formulation is presented which approximates the synthesis problem as a mixed integer linear programming (MILP) problem. Examples illustrate the method. Reported computer times suggest that earlier algorithmic methods for discovering the better sequences among those allowed by the problem formulation, and without the option of multieffecting, are an order of magnitude slower than this approach.

ISSN:0001-1541    

DOI:10.1002/aic.690310908

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractIn earlier work the authors presented a simple method to synthesize heat‐integrated distillation sequences through the use of simple sketches on a diagram displaying temperature vs. enthalpy. Embedded in that work is the useful but in‐correct assumption that the reboiler/condenser heat loads and the temperature‐difference across the column are independent of the temperature (pressure) level at which the column is operated. This assumption of constancy is removed here, and it is shown how to calculate the minimum utility target using a small linear programming formulation. It is also shown how to use the results of this calculation to synthesize distillation sequences that approach the bound discovered. For the example problems solved, the minimum utility target calculated increases about 25 to 60% over that calculated assuming constantQΔT. The sequences synthesized based on this improved target are virtually the same as the constantQΔTmethod produces, suggesting that the earlier method is indeed a useful a

ISSN:0001-1541    

DOI:10.1002/aic.690310909

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractIn horizontal two‐phase flow, transition from stratified to slug flow occurs due to the nonlinear instability of finite amplitude interfacial waves. The nonlinear equations describing interfacial waves in stratified two‐phase flow are solved by a multiple scales perturbation method. Instability criteria and amplification factors are determined. The phase velocities that are calculated to lead to amplification of finite amplitude interfacial waves are well below those based on linear stability criteria. This is in agreement with existing experimental data on transition from stratified to slug flow in horizontal chann

ISSN:0001-1541    

DOI:10.1002/aic.690310910

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY

摘要:

AbstractA method has been developed to calculate the overall mass transfer coefficient in an agitated liquid extraction column containing a wide range of drop sizes. The method applied the drop size distribution diagram to estimate the volume percentage of stagnant, circulating, and oscillating drops in the drop population. Individual mass transfer coefficients were then evaluated for the corresponding drop state, using the different single‐drop mass transfer models, after which the overall coefficientKcalwas calculated as the fractional sum of the individual coefficients and their proportion in the drop population. These estimated mass transfer coefficients have been compared with results obtained from a large rotating disc extractor 0.45 m in diameter and 6.75 m high, extracting acetone between water and Clairsol (a parafinic hydrocarbon, principally decane). Good agreement was obtained in the majority of the experiments when the Rose‐Kintner correlation was applied to evaluate the dispersed phase mass transfer coefficient of the oscillating drops. In all experiments agreement between the calculated and experimental overall mass transfer coefficients was improved by evaluating the concentration driving force by applying Simpson's rule, thereby introducing corrections for the variation in flowrate along the column and for possible backmix

ISSN:0001-1541    

DOI:10.1002/aic.690310911

出版商:American Institute of Chemical Engineers    

年代:1985

数据来源: WILEY