摘要:

AbstractThe fundamental understanding of coal and its behavior under gasification conditions is far from complete, but significant insights into the complex chemical and physical phenomena have been achieved. This review of available fundamental information focuses on thermal decomposition of coal in inert gas and in hydrogen, with emphasis on the effects on yield of products exerted by time, temperature, heating rate, pressure, hydrogen partial pressure, and particle size, and on the development of chemical and transport models of engineering importance.

ISSN:0001-1541    

DOI:10.1002/aic.690220403

出版商:American Institute of Chemical Engineers    

年代:1976

数据来源: WILEY

摘要:

AbstractThe role ofn‐butane in the formation of hydrates has been a matter of some uncertainty. The experimental measurements resulting from this work have shown conclusively thatn‐butane does enter the hydrate lattice when hydrates are formed in the presence of methane at pressures from about 1 000 to 10 000 kPa over a temperature range from 0° to about 13°C. At higher pressures and temperatures,n‐butane ceases to enter the crystal and behaves like a nonhydrate

ISSN:0001-1541    

DOI:10.1002/aic.690220404

出版商:American Institute of Chemical Engineers    

年代:1976

数据来源: WILEY

摘要:

AbstractFor injection flow of thermoplastic material in thin cavities, with some minor restrictions, both pressure and stream function obey Laplace equations. An analytical‐numerical method, with a generalized viscous model used, is developed for determining the shape of a progressing flow front and for computing flow quantities and temperature distributions. Specifically, flows in a rectangular cavity are solved and compared to experiment

ISSN:0001-1541    

DOI:10.1002/aic.690220405

出版商:American Institute of Chemical Engineers    

年代:1976

数据来源: WILEY

摘要:

AbstractBoth fibrous and polymeric additives, used alone or in combination, appear to affect primarily the fluid in the sublayer region adjacent to a solid surface, contrary to previous predictions. An analysis of fluid deformation modes shows tentatively why drag reduction levels become less sensitive to system scale when fibrous additives are employed, and why polymeric and fibrous additives may be more effective in combination than when either additive is used alone.

ISSN:0001-1541    

DOI:10.1002/aic.690220406

出版商:American Institute of Chemical Engineers    

年代:1976

数据来源: WILEY

摘要:

AbstractA two‐region model of a spouted bed, postulating vertical plug flow of gas in the spout and dispersed plug flow along curved streamlines in the annulus, is proposed. The extent of axial dispersion is accounted for by a coefficientDwhich is an adjustable parameter of the model. Experimental support for the theory is provided by residence time‐distribution data obtained by using helium gas as tracer, covering a wide range of conditions. Values of the coefficientD, determined from a comparison between predicted and observed RTD curves, are generally higher than those reported for packed beds but much smaller than those for fluidized b

ISSN:0001-1541    

DOI:10.1002/aic.690220407

出版商:American Institute of Chemical Engineers    

年代:1976

数据来源: WILEY

摘要:

AbstractA minimum cost design problem for a single‐reaction fluidized‐bed reactor system is analyzed in this paper. The problem's mathematical interest stems from Wilde's statements (1974) that there can be only two types of design to this nonlinear, nonconvex, multimodal problem. It is shown by a direct search procedure that, in fact, there are at least four types of optimal design. Furthermore, the type 3, rather than the type 1 design, is the global solution to the numerical example considered in Wilde's work, if the required auxiliary cooler cost is exclu

ISSN:0001-1541    

DOI:10.1002/aic.690220408

出版商:American Institute of Chemical Engineers    

年代:1976

数据来源: WILEY

摘要:

AbstractThe cost of a reactor‐heater system with an auxiliary cooler can have at least two local minima and a local maximum, with respect to the design variables: temperature and extent of reaction. This cost can be bounded below by a unimodal function which, being a posynomial (a sum of power functions), can be minimized efficiently by geometric programming. Construction of this lower bounding function is not obvious, since the cost involves both a definite intergral and economies of scal

ISSN:0001-1541    

DOI:10.1002/aic.690220409

出版商:American Institute of Chemical Engineers    

年代:1976

数据来源: WILEY

摘要:

AbstractComparison of solute concentrations at the outlet of a model dialyzer with values calculated from the appropriate convective diffusion equation yielded effective diffusion coefficients for mass transfer of sodium chloride in sherared suspensions of 37 to 74 μ spheres of a copolymer of styrene‐divinylbenzene. Significant mass transfer augmentation was observed over that attributable to molecular diffusion, and the effective diffusivity increased with increasing concentration of suspension but remained relatively constant with respect to shear rate over the experimental ran

ISSN:0001-1541    

DOI:10.1002/aic.690220410

出版商:American Institute of Chemical Engineers    

年代:1976

数据来源: WILEY

摘要:

AbstractStream functions are dervied for a spherical droplet in creeping flow with an arbitary surface tension gradient at its interface. The stream functions are used to show theoretically that the terminal velocity is reduced and that the interfacial velocity is retarded, especially near the rear of the droplet, when a trace of surfactant is present in the exterior phase and when surface aging is controlled by diffusion.

ISSN:0001-1541    

DOI:10.1002/aic.690220411

出版商:American Institute of Chemical Engineers    

年代:1976

数据来源: WILEY

摘要:

AbstractA predictive kinetic model has been developed for fluid catalytic cracking (FCC). The kinetic scheme involves lumped species consisting of paraffins, naphthenes, aromatic rings, and aromatic substituent groups in light and heavy fuel oil fractions. The kinetic model also incorporates the effect of nitrogen poisoning, aromatic ring adsorption, and time dependent catalyst decay. The rate constants for these lumped species are invariant with respect to charge stock composition. The predictive capabilities of the model have been verified for wide ranges of charge stocks and process conditions.

ISSN:0001-1541    

DOI:10.1002/aic.690220412

出版商:American Institute of Chemical Engineers    

年代:1976

数据来源: WILEY