Showing papers in "Chemical Engineering Science in 1974"

TL;DR: In this article, the types of dynamic behavior possible for a single first order reaction carried out in a stirred tank reaction are classified according to values of the parameters and plots in parameter space used to define the various possibilites.

TL;DR: In this article, the authors measured the concentration profiles of oxygen in the liquid phase and obtained the kLa data of the various liquid phases which only depend on the gas velocity, adjusting the experimental profiles with the predictions of the axial dispersed plug flow model.

TL;DR: In this article, the axial effective thermal conductivity in the one-phase model and the heat transfer coefficient in the twophase model were derived without assuming that the solid and gas temperatures are equal.

TL;DR: In this paper, it is suggested that large approach velocities in a bubble column may be an important factor in limiting bubble coalescence, and a theory is put forward which shows that film rupture can occur before the approaching bubbles are brought to rest.

TL;DR: In this paper, the relationship between the algebraic structure of the underlying reaction network and the extent to which open isothermal reactors might give rise to such "exotic" dynamics is discussed.

TL;DR: In this paper, a study of slugging fluidized beds has been carried out in four tubes ranging in size from 5-30 cm i.d. using particles having mean sizes 55-3380 μm and densities 0·85-2·8 gm cm−3.

TL;DR: In this article, the size distribution from a batch cooling crystallizer is predicted by the numerical solution of a mathematical model which uses empirical kinetics of nucleation and crystal growth, and the predictions clearly point out the potential advantages of controlled cooling at a constant nucleation rate for improving the product crystal size over that obtained by either natural or linear cooling.

TL;DR: In this paper, a differential equation model is derived to describe particle segregation in a binary mixture of solids fluidized by gas, which is formulated to conform with qualitative descriptions of the mechanism of segregation, yields solutions displaying the unusual features of the steady state solids-concentration profiles found experimentally and enables appraisals to be made of the relative importance of the contributary mechanisms.

TL;DR: The distribution of gas flow between bubbles and the dense phase in a fludized bed is considered in this article, where general equations for gas and solids continuity in a freely-bubbling fluidized bed are formulated.

TL;DR: In this paper, a new theoretical treatment is presented which predicts accurately the relationship between the dimensionless thickness parameter, T0, and the Capillary Number, Ca, up to a value of Ca of 2.

TL;DR: The fluidization characteristics of large particles (1000-2000 μm) have been studied using bed depths up to 30 cm in equipment having a cross-section 61 × 61 cm.

TL;DR: In this paper, a theory of programmed cooling crystallization is presented based on the moment transformation of the population balance, and numerical predictions for the behaviour of a batch crystallizer agree closely with those from an alternative theory based on discrete supersaturation balance.

TL;DR: Theoretical analyses of mass transfer in hemodialyzers which contain flowing blood and dialysate streams separated by a semi-permeable membrane are presented in this paper, where solutions are obtained in terms of well-known functions.

TL;DR: In this article, the thermal frequency response of beds packed with glass and metallic particles has been measured in the range of Reynolds numbers from 0·05 to 330 values of the coefficients of axial dispersion of heat, intraparticle thermal conductivity and fluid-particle heat transfer coefficients have been found by non-linear regression.

TL;DR: In this article, an approximate solution for absorption with irreversible second-order chemical reaction by the Danckwerts model is derived and discussed, which corresponds to the well known relation of van Krevelen and Hoftijzer for the film model.

TL;DR: In this paper, a generalized correlation is proposed for the values of effective interfacial area duing Vaporization, Absorption with and without Chemical Reaction and the value of wetted surface area in terms of dimensionless numbers.

TL;DR: In this article, a theory of comminution machines that includes the effects of classification and predicts machine contents was developed, and the relation between models of this form and energy consumption laws was investigated.

TL;DR: For rarefied gases, the collision frequency of the Krook kinetic equation is expressed as the sum of wall and gas collision frequencies as discussed by the authors, and the effective transport coefficients arise from the Chapman-Enskog theory, and are similar to those proposed by other methods.

TL;DR: In this paper, three aspects of these vibrations have been analyzed: the frequency, the critical bed height and the damping, which is the ratio of the fluid-to-solids-density.

TL;DR: In this article, a discussion of the relationship between the stresses in an ideal sphere and the reported behaviour of real particle aggregates is presented. And the strength of coagula and flocculated material is highly dependent on the size to which the aggregate has grown.

TL;DR: In this article, a simple quasisteady-state theory for concentration polarization based on a film model of mass transfer was proposed to describe the increase in permeability of a sucrose solution in cylindrical cellulose acetate membranes.

TL;DR: In this paper, the influence of a non-uniform distribution of the intrinsic catalytic activity of a single spherical pellet on its effectiveness factor, selectivity and deactivation was investigated.

TL;DR: In this paper, the approach velocity of the following bubble ( u 2 ) is experimentally obtained and its behaviour with respect to the leading bubble velocity ( u 1 ) is examined.

TL;DR: In this paper, a single pellet string reactor (SPSR) was used to simulate a packed bed reactor, which is particularly useful for larger solid particles such as pelletized ores, and also offers a convenient laboratory method for obtaining average effective diffusion coefficients for a representative sample of large porous particles.

TL;DR: The work equivalent of any material is defined as the maximum amount of shaft work or electrical energy which can possibly be obtained from it when heat and matter are exchanged with the environment as discussed by the authors.

TL;DR: In this article, the aerodynamic properties of concentrated gas-solid suspensions at low velocities were investigated and the prediction of choking flowrates and concentrations can be made from a mathematical model based on a single stability criterium.

TL;DR: The double mixed contactor as mentioned in this paper is a contactor that is especially suited for kinetic studies and it overcomes the shortcomings of present contactors and it extends the concept of gradientless reactors for heterogeneous catalysis to two fluid systems.

TL;DR: In this article, the velocity profile is calculated for slow three-dimensional flow through a simple cubic array of spheres, represented by stream function expansions which directly satisfy the equation of continuity and the no-slip conditions.