Showing papers in "Chemical Engineering Science in 1991"

TL;DR: In this paper, the key concepts involved in powder precipitation are discussed, where the thermodynamics of phase transformation is discussed, and sections on nucleation and growth follow, with the subject of crystal shape reviewed.

TL;DR: In this paper, the equilibrium swelling behavior of hydrogels sensitive to pH or ionic strength changes of the swelling medium was studied using new structural models which are based on the Flory-Huggins thermodynamic theory, the rubber elasticity theory, and ionic interaction deviations therefrom.

TL;DR: In this paper, a method is proposed for the determination of the connectivity of porous solids, such as adsorbents and catalyst supports, from the analysis of nitrogen sorption measurements based on the use of percolation theory to analyse sorption hysteresis.

TL;DR: In this paper, a general formulation for power absorbed in a homogeneous, isotropic multilayered medium exposed to plane waves from both faces has been developed, and temperature profiles obtained by solving the transient heat conduction equation with the microwave power as a source term.

TL;DR: In this paper, the authors present experimental results obtained in an accelerated carbonation apparatus using a variety of techniques, including TGA, and extend the mathematical model developed recently to include the entire range of ambient relative humidities.

TL;DR: In this paper, a compilation of data and model interpretation of CO2 absorption/desorption with mixtures of MDEA (methyldiethanolamine), MEA (monoethanolamine), and DEA (diethanoline) was presented.

TL;DR: In this article, the effect of pressure on the hydrodynamics of trickle-bed reactors is investigated, and two new correlations for the pressure drop and the liquid hold-up for non-foaming liquids are proposed; they are based on 1500 experimental results.

TL;DR: Modelling methods for modeling drug transport in tissue in the vicinity of a continuous source found molecules that are water-soluble, slowly eliminated, and diffusible are the best candidates for polymeric delivery to brain tissues.

TL;DR: In this article, the authors performed experiments on evaporation kinetics of droplets of water, colloidal silica, sodium sulphate and skimmed milk, and the experimental procedure was similar to that proposed by Charlesworth and Marshall (1960, A.I.Ch.E.J.6, 9−23).

TL;DR: In this paper, the authors analyzed the effect of the square cross-section of a capillary by viewing both side and diagonal planes of the capillary in order to analyze the effect.

TL;DR: In this article, the influence of increased gas density on the gas holdup in bubble column reactors was analyzed and a simple model for describing the holdup was also proposed, showing that the major effect of increasing gas density is to stabilize the regime of homogeneous bubble flow and, consequently, to delay the transition to the churn-turbulent flow regime.

TL;DR: In this article, experimental observations on the dispersion of fluid in horizontal and vertical tubes where periodic baffles and fluid oscillation may be present were made both at the center and wall of the tube.

TL;DR: In this article, the influence of operating conditions, particle properties and bed diameters on radial voidage profiles in circulating fluidized beds operating in the fast regime has been investigated in gas-solid systems.

TL;DR: In this paper, the Navier-Stokes system is used to estimate the thickness variations over distances long compared to the mean film thickness, and augmented with conjoinging pressure.

TL;DR: In this article, a modified UNIQUAC equation with concentration dependent parameters was used for correlation and prediction of salt effects on vapor-liquid equilibria (VLE) of mixed solvents.

TL;DR: In this article, the authors examined the rate of bubble breakage in turbulent liquid flow using a population balance containing a bubble-breakage model to analyze experimental burstage rate data.

TL;DR: In this paper, a mixed integer nonlinear programming (MINLP) formulation is presented for the synthesis of isothermal separator-recycle systems with a variety of objectives such as the minimization of the total annual cost of the plant and the maximization of its profit, as well as objectives traditionally used for optimizing the performance of a reactor network.

TL;DR: In this paper, the formation and growth of cakes in cake filtration taking into account of cake compression and the moving-boundary nature of the growth process are derived and methods for their solutions developed.

TL;DR: In this paper, a Monte Carlo computer simulation model for a class of particle transport processes in flow through a porous medium is developed, which includes transport of macromolecules in porous media, fines migration, flow of stable emulsion, deep-bed filtration and size-exclusion chromatography.

TL;DR: In this paper, the results of detailed numerical simulations using such a model for the flow generated by a downflow-pitched blade turbine in a fully baffled cylindrical vessel and the subsequent bulk mixing are described.

TL;DR: In this article, the radial porosity model is correlated in terms of the diameter aspect ratio and a non-dimensional distance from the container wall, which can be used in analytical transport models for simulating packed beds of uniform spheres in cylindrical containers.

TL;DR: In this paper, numerically generated flow visualisation simulations for the flow of an incompressible Newtonian fluid within a two-dimensional channel which can contain periodic baffles are presented.

TL;DR: In this paper, an experimental study of the axial segregation process for particle mixture of different sizes is presented. And a mechanism for the segregation process is presented based on which criteria for axial separation are discussed.

TL;DR: In this paper, the authors show how intraparticle convection affects residence time distribution of inert and linearly adsorbed species in fixed-bed processes and demonstrate how column efficiency is improved by the use of large-pore supports.

TL;DR: In this paper, an expression relying on fluid mechanical and phenomenological considerations is proposed for the agglomeration rate of adipic acid crystals during their crystallization in a mechanically stirred crystallizer.

TL;DR: In this paper, a mathematical description for a flowing mixture of solid particulates and a fluid is developed within the context of mixture theory, and the equations governing the flow of a two-component mixture of a Newtonian fluid and a granular solid are derived.

TL;DR: In this article, the hydrodynamic response of a small suspended sphere to laminar flow is studied for relatively fast flow rates in a duct with porous walls, and an expression is developed, from first principles, to predict conditions under which a sufficiently long cross-flow plate and frame membrane module exposed to dilute suspensions of essentially spherical particles will not foul, assuming nonhydrodynamic attractions between a particle and the membrane are negligible.

TL;DR: In this article, the Patel-Teja equation of state (PT EOS) is extended to phase equilibrium calcultations for electrolyte solutions under high pressure by adding a Debye-Huckel electrostatic contribution term.

TL;DR: In this paper, the authors investigated the low-pressure methanol synthesis over Polish commercial catalyst CuO (60% wt), ZnO (30%) and Al 2 O 3 (7.5%).

TL;DR: In this article, a new approach for calculating minimum flows in simple distillation columns is presented, which is suited for the evaluation of a large number of distillation sequences in terms of energy consumption at early stages of process design.