Showing papers in "Chemical Engineering Science in 1989"

TL;DR: In this paper, the authors define les limitations de la modelisation du milieu poreux par un faisceau de tubes capillaires sinueux and paralleles.

TL;DR: In this paper, the application of countercurrent and simulated counter-current process schemes to adsorption separations is reviewed with emphasis on industrial-scale operations and mathematical modelling, and the results of the application are presented.

TL;DR: In this paper, the authors measured turbulence parameters in a baffled, Rushton turbine agitated vessel with a laser-Doppler velocimeter, and the necessary corrections for the periodic, nondissipative velocity fluctuations in the near impeller region were made by an autocorrelation method.

TL;DR: In this paper, a capillary type model with wall effect corrections is proposed to determine the pressure drop through packed beds of parallelepipedal particles, where the tortuosity factor and the dynamic specific surface area are used as mean structure parameters.

TL;DR: In this paper, a thermal adsorption equation in a virial form is proposed to describe the pressure and temperature dependence of data and its behavior over a wide range of temperatures and pressures.

TL;DR: In this article, the sintering rate of calcium oxide in a nitrogen atmosphere was measured at temperatures from 700 to 1100°C, and the model of German and Munir (J. Am. Ceram. Soc., 59, 379-383, 1976) correlates the kinetics of surface reduction and identifies lattice diffusion as the mechanism of solid transport.

TL;DR: In this paper, a thin amorphous SiO 2 film was deposited within the walls of porous Vycor tubes by SiH 4 oxidation in an opposing-reactants geometry: SiO 4 was passed inside the tube while O 2 was passed outside the tube.

TL;DR: Despite the simplifying approximations involved in the derivations, the models demonstrate a satisfactory and very useful ability to quantitatively interpret population assays for bacterial and leukocyte chemotactic migration.

TL;DR: In this article, experimental and theoretical results are reported on pressure swing adsorption (PSA) for the separation of a methane/carbon dioxide mixture which has direct applications in landfill gas and tertiary oil recovery effluent separations.

TL;DR: In this article, the theoretical limit of Sherwood number 2 for spherical particles suspended in stirred tanks was confirmed, which is the first systematic experimental confirmation that the theory is valid for spherical particle suspensions.

TL;DR: In this paper, a mathematical model of the pyrolysis of wet particles of wood is presented, which integrates a conventional description of the physical and chemical phenomena involved in the dry particle of wood, and a simplified drying model.

TL;DR: In this article, the authors report experimental observations on both flow patterns and energy losses for oscillatory flow in geometries that can contain sharp edges and show that large scale eddy mixing can be generated in regions between sharp edges.

TL;DR: In this article, the authors developed relations for predicting gas and liquid mass transfer coefficients in rotating packed beds based on laminar liquid film flow on a rotating blade and rotating disk, and the assumed random distribution of surfaces in the rotating bed.

TL;DR: In this article, an industrial Ni catalyst supported on CaOTiO2O2Al2O3 was characterized, used for methane reforming with carbon dioxide, and compared with catalysts containing Ni on other supports Conversions close to 100% were achieved during 51 h on stream for a CO2: CH4 ratio of 264: 1 using a weight hourly space velocity of 738 h−1 despite solid state reactions and sintering which decrease the surface area.

TL;DR: In this paper, experiments on a cascading adsorptive heat pump are reported, and the results show that the components which limit the power of the unit are the evaporators and basically water evaporator.

TL;DR: In this article, a general analysis of exact lumping is presented, which can be applied to any reaction system with n species described by a set of first order ordinary differential equations dy/dt = f(y).

TL;DR: In this paper, the transient operation of monolithic catalytic converters was stimulated using a two-dimensional equivalent continuum model that allowed us to systematically evaluate the effects of nonuniform flow disributions, of ambient heat losses, and of radially varying catalytic activity profiles on reactor performance.

TL;DR: In this paper, a simple model based on equilibrium theory for simulating countercurrent adsorption separation processes involving multiple components and nonlinear equilibrium has been developed, where the emphasis has been placed on the role of the desorbent and the effect of the physical state of the fluid, i.e. vapor or liquid phase operation.

TL;DR: In this article, the first reported set of experimental measurements, based on chemical absorption of CO2 in NaOH, of gas and liquid mass-transfer coefficients in a rotating bed as a function of rotational speed and liquid flow rate were presented.

TL;DR: In this article, necessary and sufficient conditions for detailed balancing in mass action systems of arbitrary complexity are given for a general class of action systems, where the rate constants are suitably well orchestrated.

TL;DR: In this paper, a single baffled tube geometry is examined with a fixed net flow through the tube, and it is found fluid oscillations can have a significant effect on the systems residence time distribution.

TL;DR: In this paper, an absorption model has been developed which can be used to calculate rapidly absorption rates for the phenomenon mass transfer accompanied by multiple complex parallel reversible chemical reactions, for both film and penetration model.

TL;DR: The ideal adsorbed solution (IAS) theory is a thermodynamic method for predicting multicomponent adsorption equilibria from isotherms for single gases as discussed by the authors.

TL;DR: In this paper, measurements of solute and solvent transport in swollen, swelling, and collapsing hydrogels are described, with diffusion coefficients varying only slightly with the degree of the swelling.

TL;DR: In this paper, a 16MW fluidized-bed boiler was studied and the authors showed that CaSO 4 is decomposed to CaO with subsequent release of SO 2 at temperatures above 880-890°C, and at an excess air ratio of 1.4.

TL;DR: In this paper, a method to evaluate the decay of concentration variance in turbulent mixers is presented, which links large-scale convective motions and turbulent dispersion with successive stages of micromixing process (inertial-convective disintegration of large eddies, formation of laminated structures within energy dissipating vortices and molecular diffusion within deforming laminate structures).

TL;DR: In this article, a numerical model was developed to simulate the kinetic separation of air in a carbon molecular sieve pressure swing adsorption unit, which was extended to the equilibrium selective separation over a zeolite adsorbent in which nitrogen preferentially adsorbed, leaving oxygen as the pure raffinate product.

TL;DR: In this paper, an improved implementation of the Thorne-Enskog equations for the evaluation of the viscosity of high-density fluid mixture is presented and tested against a body of experimental data and found to yield results with experimentally and universally acceptable accuracy for practical purposes.

TL;DR: In this article, Sioda et al. calculated mass transport rates in cross flow at cylindrical wire electrodes, using two-electrode thin-layer electrochemistry.

TL;DR: In this article, a method for the calculation of simultaneous chemical and phase equilibria at specified temperature and pressure is presented, and an algorithm for automatic selection of independent chemical reactions is improved and extended to nonideal mixtures.