Showing papers in "Chemical Engineering Journal in 1972"

TL;DR: In this article, axial dispersion coefficients (EA) in beds of small (0.1-1 mm) particles are often needed to interpret reaction rate data and a chromatographic technique was used to evaluate such coefficients for beds of porous catalyst particles and beds of non-porous glass beads over a wide range of velocities (Rep = 0. 00237 to 11.9).

TL;DR: In this paper, the van der Waals model of a dense fluid is represented by a simple partition function and it is shown that this function, coupled with a choice of plausible ad hoc assumptions, leads to any one of several well-known equations of state including the empirically successful equation of Redlich and Kwong.

TL;DR: It is pointed out that the proposed algorithms are faster and more reliable than those presented in the early publications on orthogonal collocation.

TL;DR: In this article, a numerical technique for the inversion of Laplace transforms is reviewed and compared with an alternative method and with analytical values and the technique is shown to give highly accurate results.

TL;DR: In this paper, the authors measured the mixing and mean residence times of the liquid phase in two-phase trickle flow in packings in terms of the dispersion model, and the results were correlated by Pe1 = 1.00(Re1)0.70Ga−0.32.

TL;DR: In this article, a method for estimation of the parameters in a linear flow model with time invariant parameters based on a least-squares error analysis in the time domain is described, and numerical examples for two commonly used models containing two and four parameters, respectively, are given.

TL;DR: In this article, the fluidisation characteristics of spherical particles of such a size and density that the velocity of gas in the dense phase exceeds the rising velocity of the bubbles have been studied.

TL;DR: An improved mode of representation for networks resulting from process simulation flowcharts is presented based on the signal flowgraph concept, which is applicable to equation-ordering problems if the output set is selected a priori.

TL;DR: In this paper, numerical solutions of the Navier-Stokes equations have been used to extend both the Happel free surface and the Kuwabara zero vorticity cell models to creeping flow past swarms of spheroids and banks of elliptical cylinders.

TL;DR: In this paper, it was shown that the free surface of a liquid bridge or a soap film which connects the edges of flat coaxial parallel plates is generated by rotation of a curve representable as r = r(z), which is stable towards small axisymmetric disturbances and also stable for small non-axisymetric disturbances when both types of disturbance leave invariant the end circles and the volume enclosed by the free surfaces and end plates.

TL;DR: In this paper, the rate of two-phase nitration of toluene has been determined in a stirred batch reactor over the range 62-78% sulphuric acid using an initial nitric acid concentration of 0.56 mol l −1 and a molar ratio of n-to-luene of 1.06:1.

TL;DR: In this article, an experimental investigation of the rate of transfer of oxygen from the gas phase to the liquid phase in gas-liquid fluidised beds of glass ballotini of 1-mm and 6-mm dia.

TL;DR: In this article, conditions for homogeneous steady-state suspension in a continuous stirred tank crystalliser were found, where pre-formed particles were used in many configurations of stirred tanks, and the evolution and characteristics of an apparatus which closely approximates the ideal conditions were described in detail.

TL;DR: In this paper, a theoretical analysis of the adiabatic adsorption of two solutes subject to the Langmuir isotherm is presented, based on the theory developed in Part I.

TL;DR: In this paper, an analytical solution based on penetration theory has been derived for the case where the chemical equilibrium constants of the first and second step reactions, K1 and K2, are very large and the diffusivities of all species are equal, and the reaction factor in this case has been shown to be a function of the equilibrium constant ratio K1/K2.

TL;DR: In this article, it is shown that lumped kinetic models may be valid for reaction mixtures containing a continuum of components, and special attention is given to lumping of continuous monomolecular reaction systems.

TL;DR: In this article, the break-up of capillary jets of very viscous and jellified non-Newtonian liquids has been investigated, and it was shown that the instabilities observed with the inelastic fluids are related to the time needed to reform the structure of the liquid.

TL;DR: In this paper, a rheological model for non-Newtonian fluids is proposed, where a molecular arrangement parameter, which is related to the entropy, is introduced and the entropy of the fluid varies with the change of the molecular arrangement parameters which is induced by the shear stress or the rate of strain applied to the fluid.

TL;DR: From a comparison of the rates of physical absorption of oxygen into saturated or inactivated blood and hemoglobin solutions with those into water and sodium chloride solutions in the same vessel, the effective diffusivity of oxygen through the saturated orinactivated blood was obtained as a function of hematocrit.

TL;DR: In this paper, heat transfer coefficients were obtained for water heated in upward and in downward flow in vertical tubes in the range 5800-71 000 for both upward and downward flow.

TL;DR: In this paper, the authors present a strategy which fully exploits dual bounding information to select the best of several proposed modifications at each step in the synthesis of a process flow sheet.

TL;DR: In this article, an analytical-numerical solution of the energy balance for a non-catalytic gas-solid reaction occurring in a spherical particle is derived and the effects of chemical and mass transfer resistances on the maximum temperature rise are investigated.

TL;DR: In this paper, the problem of gas absorption in films of non-Newtonian fluids falling over flat and spherical surfaces was studied, and the resulting Sturm-Liouville problem was solved by series expansion on a digital computer.

TL;DR: In this paper, the role of the energy state is carefully examined and some consideration is also given to the phenomenon of the adsorptivity reversal in the high temperature range where the energy states has a significant effect on adsorption performance.

TL;DR: In this paper, a model based on Bingham-plastic fluid behavior for the particulate phase of a fluidized bed predicts particle trajectories about a rising bubble which are in good agreement with observed particle trajectory.

TL;DR: In this article, two distinct modes of continuous, direct thermal parametric pumping are simulated using a computer solution of the PDE model, parameters for which are obtained entirely from batch experiments.

TL;DR: In this article, the mean drop size of densely packed liquid-liquid dispersions has been measured in a spray column using a photographic technique, and a correlation predicting the mean size is proposed, the drops resulting from break up of jets formed with perforated plates.

TL;DR: In this article, the authors measured the thickness of the film of liquid falling on a sphere and obtained fair agreement with theoretical relationships for both these cases with respect to the presence and absence of a surface film on the surface.

TL;DR: In this paper, general equations for the velocity distribution, pressure-flow characteristics and residence time distribution in the absence of diffusion are given in the presence of diffusion and diffusion are analyzed.