bluuebunny/crossref_metadata_2025_split huggingface dataset:
A comparison of propane and carbon dioxide solvent flooding processes
Authors: Holm L. W. 
Published: June 2004

AbstractA laboratory investigation was conducted on oil displacement from porous media by the use of either a slug of propane followed by gas or a slug of carbon dioxide followed by water. A comparison was made of the efficiencies of these two solvent flooding processes for petroleum reservoirs. The results of flooding experiments on cores and on scaled pattern models showed the effect, on oil recovery, of type of porous medium, pore geometry, length to width ratio of the flood pattern, fluid viscosities, and miscibility. Oil recoveries of from 60 to 80% of the original oil in place were obtained by these solvent flooding processes as compared with conventional waterflood recoveries of between 35 to 50% on the same cores and linear models. Furthermore these recoveries were obtained with solvent slug sizes of 10 to 30% of a hydrocarbon pore volume, with less solvent being required as the length of the flood path increased. Data showing the relations between mobility ratio and volumetric sweep efficiency for the propane‐gas and carbon dioxide water flooding processes for two widely different types of porous medium are included in this paper.It was concluded that in reservoirs where pressure, oil viscosity and composition, and flooding pattern are favorable, either of these solvent flooding processes would give oil recoveries considerably higher than conventional waterflood or gas drive. It was further concluded that this improved recovery would be realized earlier in the life of a flood with carbon dioxide‐carbonated water than with propane followed by gas.
Deposition of aerosol particles in fibrous filters
Authors: Thomas D. G. , Lapple C. E. 
Published: June 2004

AbstractThe collection efficiency of glass fiber pads was investigated with a super cooled liquid aerosol. A filter‐velocity range of 0.02 to 20 ft./sec. was covered with filter pads having a bulk density ranging from 1 to 10 lb./cu. ft. and a fiber diameter ranging from 1 to 30 μ.For the aerosol employed the results showed a minimum collection efficiency at a velocity of 2 to 5 ft./sec., dependent on fiber size. At the lower velocities, where diffusion is controlling, collection efficiency increased with decreased velocity; at higher velocities, where inertia is controlling, efficiency increased with increased velocity.For purposes of generalization the data were correlated in terms of dimensionless parameters which allow for the combined effects of flow‐line interception, inertial interception, and diffusinal deposition. Evaluation of the data in terms of existing theories of deposition indicated nominal agreement with the theory of Langmuir, as modified by Natanson, for diffusional deposition. For inertial deposition the measured collection efficiencies were considerably lower than would be predicted from the theoretical values reported by Langmuir and Blodgett for potential flow around the fibers, presumably because of the viscous‐flow (low Reynolds number) conditions that prevailed in this study.
Turbulent convective heat and mass transfer from accelerating particles
Authors: Pasternak I. S. , Gauvin W. H. 
Published: June 2004

AbstractThe rate of evaporation of acetone from single particles accelerating freely in a downward concurrent turbulent air stream was studied over a range of air velocities from 40 to 70 ft./sec. and at a constant air temperature of 410°F. The particles consisted of celite in the shape of spheres, cubes, disks and cylinders, varying in size from 0.15 to 0.40 in. Accurate particle velocity data were obtained with a new radioactive tracer technique, and high‐speed photography at two positions along the column permitted measurement of the rate of rotation and showed that the particles rotated in a random manner.Adequate prediction of the observed heat and mass transfer data could be obtained from the integration of a rate eequation previously reported for stationary particles. The concept of a new characteristic dimension, developed for the latter case, was found to be applicable to randomly rotating shapes and to account satisfactorily for the behaviour of nonspherical particles.
Entrainment from a submerged combustion evaporator
Authors: Rey George 
Published: June 2004

AbstractEntrainment from a submerged combustion evaporator system was studied with sodium ion as a tracer. By measuring the ratio of the sodium concentration in the pot to that in the condensate the entrainment removal performance of the evaporator system was studied under various conditions. It was observed that the log of the concentration ratio decreases with an increase in the temperature of the gaseous products of combustion as they emanate from the combustion chamber into the solution. This is attributed to the fact that a greater amount of fine (< 5 μ) droplets of entrainment are formed in the evaporator as the temperature of the gases increases.
Application of the corresponding states principle to mixtures of low molecular weight gases at low temperatures and high pressures
Authors: Leland Thomas W. , Kobayashi Riki , Mueller William H. 
Published: June 2004

AbstractThis paper presents an extension of the corresponding states principle to mixtures of low molecular weight, nonpolar gases at low temperatures. It corrects the corresponding states principle for quantum mechanical effects but neglects any deviation from Maxwell‐Boltzmann statistics. A comparison is made between compressibility factors obtained from reduced second‐virial coefficients and those obtained from pseudo‐critical values. The use of reduced virial coefficients is limited by the fact that there are not enough experimental data to permit extensive correlations of third‐virial coefficients. The pseudo‐critical expressions derived for higher temperatures are accurate at cryogenic temperatures provided the reference substance chosen has a molecular weight close to that of the mixture as well as a similar molecular shape.
Mechanics of semifluidization of single size particles in solid‐liquid systems
Authors: Fan Liang‐Tseng , Wen Chin‐Yung 
Published: June 2004

AbstractMechanical and dynamical characteristics of semifluidized beds of single‐size particles in solid‐liquid system were investigated. A semifluidized bed is a type of fluidized bed in which the bed expansion is partially restricted. The emphasis was placed on the study of packed bed formation and pressure drop increase when the semifluidized beds were formed by the compression of fluidized beds. The data showed good agreement with the theoretical and semiempirical equations based on a simple model of fluidized beds.The results of this investigation would also contribute to the understanding of fluidized beds.
The transport properties of carbon dioxide
Authors: Kennedy John T. , Thodos George 
Published: June 2004

AbstractExperimental viscosity, thermal conductivity, and self‐diffusivity data available in the literature for carbon dioxide have been critically reviewed and used to develop reduced state correlations of the transport properties for this substance. These correlations should apply to nonpolar compounds having critical compressibility factors approximately equal to that of carbon dioxide,zc= 0.275.In order to establish the dependence of these transport properties in the high pressure and liquid state regions, use has been made of relationships between the residual properties, μ‐μ*, k‐k*, and (P𝒟)*‐(P𝒟) and density. These residual quantities represent the differences between the values of the properties at any pressure and temperature and those at atmospheric pressure and the same temperature. These relationships also allow the determination of the values of the transport properties at the critical point. The resulting critical values along with the residual relationships enabled the construction of reduced state correlations for viscosity, thermal conductivity, and the product of self‐diffusivity and pressure for carbon dioxide.These correlations extend from the saturated vapor and liquid states to reduced temperatures ofTR= 10 and reduced pressures ofPR= 50. Comparisons made between values resulting from these correlations and corresponding experimental values, including the region of high pressure for both the gaseous and liquid states and the vicinity of the critical point, produced an average deviation of 2.0% for viscosity, 1.4% for thermal conductivity, and 5.9% for self‐diffusivity.
Dynamics of fractional distillation
Authors: Ceaglske N. H. 
Published: June 2004

AbstractOne of the numerous equations needed to define the dynamics of a distillation column has been derived. This equation relates the feed composition to the product composition. Thederivation is accomplished by the reduction of the signal flow diagram. The poles and zeros of the equation are almost entirely determined by the ratio of the tray holdup to the liquid flow rates and the number of trays.
Heat transfer from the surface of a steam bubble in turbulent subcooled liquid stream
Authors: Bankoff S. G. , Mason J. P. 
Published: June 2004

AbstractTurbulent heat transfer coefficients have been measured at the surface of single bubbles formed by injecting steam into a subcooled water stream at atmospheric pressure. Depending upon the steam flow rate (0.4 to 1.5 g./min), the water temperature (80° to 180°F.), and the water velocity (0.9 to 7.2 ft./sec.) the bubbles ranged from small, smooth, ellipsoidal bubbles, similar to those observed in highly subcooled nucleate boiling, to large, irregular bubbles which oscillated in size. The bubble frequencies were in the range 200 to 2,500 cycles/sec. and the surface heat transfer coefficients 13,000 to 320,000 B.t.u./(hr.) (sq. ft.) (°F.). Because of these exceptionally high heat transfer coefficients a significant fraction of the total heat flow in Gunther's subcooled boiling experiments is estimated to be attributable to latent heat transport.
Rates of reaction in a recycling system—dehydration of ethanol and diethyl ether over alumina
Authors: Butt John B. , Bliss Harding , Walker C. A. 
Published: June 2004

AbstractA new method for measuring isothermal rates of heterogeneously catalyzed gas reactions is described. The method involves a differential reactor incorporated in a recycling system and affords ease of control, accuracy, and many rate measurements in one run.The results for the reaction system investigated show that four reactions are important: the dehydration of ethanol to ethylene, the reaction of ethanol to form diethyl ether, the dehydration of diethyl ether to ethylene, and the reaction of diethyl ether to form ethanol.It is also shown that the rate controlling steps are the monomolecular surface reactions for the two dehydrations and for the formation of ethanol from diethyl ether, and the bimolecular surface reaction for the formation of diethyl ether from ethanol.The values and the temperature dependence of all pertinent rate and adsorption constants are determined and reported, and they are shown to correlate very well the data up to 80% conversion.
Physical and chemical forces in solvent selectivity for hydrocarbons
Authors: Anderson Ralph , Cambio Ronald , Prausnitz J. M. 
Published: June 2004

AbstractAn analysis is given of the role of physical and chemical forces in determining the selectivity of a solvent for different hydrocarbons. The physical contribution to selectivity depends on the polar energy density of the solvent and on the difference in size of the hydrocarbons to be separated; this effect is well‐demonstrated by solvent selectivity data for paraffins where no chemical forces are important. The chemical contribution depends on the ability of the solvent to form acid‐base complexes with the hydrocarbon. Chemical forces leading to complex formation can be detected by measurements on the heat of mixing, the volume change of mixing, and on the ultraviolet absorption of solvent‐hydrocarbon mixtures; some illustrations of such measurements are presented. Finally an equation is proposed for correlating selectivity data in extractive distillation, and its applicability is demonstrated with activity coefficient data for saturated and unsaturated hydrocarbons in various polar solvents.
Volumetric properties of gas mixtures containing one or more polar components
Authors: Blanks R. F. , Prausnitz J. M. 
Published: June 2004

AbstractA study has been made of the second virial coefficients of binary gas mixtures containing one or two polar components. Methods for calculating these coefficients are presented. The interaction coefficient Bij for a polar‐polar interaction cannot be calculated with the Stockmayer potential with pure component parameters only; such calculations tend to underestimate the strong forces of attraction between dissimilar polar molecules. It is shown that the characteristic distance for the reduced dipole moment for two dissimilar polar molecules is less than the arithmetic average of the distance parameter of the similar molecules by an amount which can be related to the enthalpy of complex formation. When this corrected collision diameter is used in the Stockmayer potential, good results can be obtained for interaction coefficient Bij. In the case of a polar‐nonpolar mixture the coefficient Bij depends on dispersion and on induction forces. Techniques are proposed for estimating these forces from pure component parameters, and it is shown that for accurate calculation of Bij it is necessary to correct for the displacement of the dipole from the center of the polar molecule. The paper concludes with some illustrations of how these ideas may be applied to typical chemical engineering problems.
Diffusion of ideal gases in capillaries and porous solids
Authors: Scott D. S. , Dullien F. A. L. 
Published: June 2004

AbstractThe steady state diffusion of gases through capillaries or through the pores of a solid when the total pressure in the system is constant is considered. It is shown that the ratio of the molar diffusion rate of the lighter gas to that of the heavier gas must be equal to the square root of the ratio of the molecular weight of the heavier to the lighter.From simple momentum transfer considerations a diffusion equation is derived to describe the diffusion rate as the nature of the process changes from ordinary mutual diffusion to Knudsen diffusion. This equation is shown to give good agreement with experimental measurements of diffusion rates in porous solids. A structural parameter of the porous solid, the diffusion ratio, is calculated from the experimental results and compared with the experimental value of the same ratio found from electrical resistance ratios and from flow measurements.
Sprays formed by flashing liquid jets
Authors: Brown Ralph , York J. Louis 
Published: June 2004

AbstractLiquids forced from a high‐pressure zone into a low‐pressure zone often cross the equilibrium pressure for the liquid temperature and disintegrate into a spray by partial evolution of vapor. The ordinary aerosol dispenser is a common example of this operation, and flash boiling is another.This paper reports on a study of the sprays formed by such a process and of the mechanism of spray formation. Sprays from water and Freon‐11 jets were analyzed for drop sizes, drop velocities, and spray patterns. The breakup mechanism was analyzed and data presented to show some of the controlling factors.A critical superheat was found, above which the jet of liquid is shattered by rapid bubble growth within it. The bubble‐growth rate was correlated with the Weber number, and a critical value of the Weber number was found to be 12.5 for low‐viscosity liquids. The mean drop size was also correlated with Weber number and degree of superheat.The spray from rough orifices and sharp‐edged orifices was compared with sprays produced from cold liquids by other techniques and was found to be comparable in all respects except temperature.
Heat transfer to pseudoplastic fluids in laminar flow
Authors: Christiansen E. B. , Craig S. E. 
Published: June 2004

AbstractA simple temperature dependent equation τ = K [Ṡ exp(ΔH‡/RT)]n is proposed to represent the rheological properties of pseudoplastic fluids. This equation is combined with the differential equations describing steady state laminar flow and heat conduction to a moving fluid when natural convection and thermal energy generation are negligible. The resulting equations are solved numerically for heating of both Newtonian and non‐Newtonian fluids in laminar flow in tubes of circular cross section with constant wall temperature. These numerical solutions are presented as generalized plots of Nusselt number vs. Graetz number with n and (ΔH‡/R) (1/Ti — 1/Tw) as parameters.Extensive experimental data were obtained for two pseudoplastic fluids, and, in the range where natural convection was unimportant, the mean deviation between the computed Nusselt numbers and measured Nusselt numbers was ± 7%.
The viscosity of polar gases at normal pressures
Authors: Stiel Leonard I. , Thodos George 
Published: June 2004

AbstractThe viscosity behavior at normal pressures (0.2 to 5 atm.) of fifty‐three polar gases was examined, and equations representing the dependence of viscosity on temperature for these gases were developed. A dimensional analysis approach was applied to the variables effecting the viscosity of polar gases at moderate pressures. These variables were assumed to be the molecular weight, temperature, and the critical constants of the substance.Reliable viscosity data available in the literature for the polar gases investigated were utilized to determine the exact dependence of their viscosities on these variables. In contrast to the results of a previous study, which show that for nonpolar gases the viscosity parameter μ*ξ (where ξ =Tc⅙/M½Pc⅔) is independent ofzc; the results of the present study indicate that for polar gases this parameter is dependent onzc. The viscosity parameters of gases which exhibit hydrogen bonding were found to depend uniquely onzc5/4and reduced temperature, while the remaining polar gases were found to exhibit a different unique dependence onzc⅔and reduced temperature. For these two classes of polar substances separate viscosity relationships were developed.For eleven gases which exhibit hydrogen bonding viscosities were calculated and compared with corresponding experimental values. An average deviation of 1.47% resulted from 129 experimental points. For the other polar gases the calculated values were also compared with experimental values and produced an average deviation of 2.59% for 197 experimental points.
Coalescence frequencies in agitated liquid‐liquid systems
Authors: Madden A. J. , Damerell Glenn L. 
Published: June 2004

AbstractAn experimental technique is described for estimating the coalescence frequency of droplets in an agitated liquid‐liquid system. Results are presented for dilute aqueous dispersions in toluene. Quantitative estimates of the coalescence frequency are based upon a simple model proposed to describe the coalescence process. The coalescence frequency is shown to increase markedly with increase in impeller speed and to a lesser extent with increase in the dispersed‐phase volume.
The flow of rarefied gases
Authors: Scott D. S. , Dullien F. A. L. 
Published: June 2004

AbstractIt has been shown experimentally by Knudsen and others that gases flowing at decreasing total pressures through small capillaries pass from a region of Poiseuille flow to a so‐called slip flow region which contains a flow minimum. Frequently the practice has been followed of approximating this behavior with a linear relationship which, although it gives a fairly good approximation to the actual curve, is incomplete in theory.A new equation for the flow of gases in capillaries is presented, in which all flow constants can be calculated from the simple kinetic theory of gases. It is shown that this equation reproduces the experimental results of Knudsen and others over the entire range of laminar, slip, and Knudsen flow within the accuracy that might be expected from the simple kinetic model adopted.Some discussion of the use of this equation in the design of vacuum piping and its applicability to flow through porous solids is also given.
Lennard‐Jones force constants from viscosity data: Their relationship to critical properties
Authors: Flynn Lawrence W. , Thodos George 
Published: June 2004

AbstractLennard‐Jones force constants calculared from viscosity values at normal pressures for nearly forty nonpolar organic and inorganic substances have been used to develop relationships for the estimation of these constants from the critical temperature and volume of the substance. The product of the critical temperature and volume TcVc was found to correlate linearly with the force constant modulus \documentclass{article}\pagestyle{empty}\begin{document}$ \frac{\varepsilon }{\kappa }\sigma ^3 $\end{document}.When the collision diameter ρ was plotted against the cube root of the critical volume on log‐log coordinates, a straight line of slope 5/4 resulted. The corresponding relationship was found to predict ρ values with an average deviation of 3.1% when compared with values calculated from viscosity measurements. The temperature force constant ϵ/κ was found to vary as the 5/6 power of the critical temperature, and the resulting relationship produced an average deviation of 10%.
Adsorption of normal paraffins and sulfur compounds on activated carbon
Authors: Grant R. J. , Manes Milton , Smith S. B. 
Published: June 2004

AbstractAdsorption isotherms on activated carbon were determined gravimetrically for normal C1 and C3‐C6 paraffins and subsequently for methyl, ethyl, and n‐propyl mercaptans, hydrogen sulfide, carbonyl sulfide, and carbon disulfide, at pressures up to 1 atm. and from −23° to 100°C. Orthobaric liquid densities at low temperatures of some of the sulfur gases were determined pycnometrically. The adsorption data on correlation by the method of Lewis, Gilliland, Chrtow, and Cadogan (1) gave two separate curves, one for the paraffins and one for the sulfur compounds. The results show the correlation to be useful for estimating the adsorptive capacity of chemically similar compounds from a minimum of experimental data.
Flow of gases through porous solids under the influence of temperature gradients
Authors: Gilliand E. R. , Baddour R. F. , Engel H. H. 
Published: June 2004

AbstractThe isothermal and isobaric flow of pure gases and vapors through microporous Vycor glass was investigated under such conditions that the gas‐phase flow occurred by Knudsen diffusion. The isothermal flows and the isobaric flow of nonadsorbed gases are correlated by existing relationships.On the assumption that surface flow is a diffusive process and that equilibrium exists between the vapor and solid throughout the porous media, a correlation for the nonisothermal surface flow is developed. The factors determining the rate of surface flow are the physical properties of the solid, the temperature level and gradient, the enthalpy of adsorption, the surface concentration and spreading pressure of the adsorbed phase, and the activation energy and coefficient of resistance for surface diffusion. The latter two factors can be evaluated from isothermal surface flow measurements; hence no new arbitrary constants are required in the correlation. Agreement between predicted and measured surface flows is good for ethylene and propylene at a mean temperature of 25°C. Both the gas‐phase and surface flows are from the cold to hot end of the porous solid.It is suggested that the use of temperature gradients in porous solids and plastic films for separating mixtures of vapors be investigated.