bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mass transfer from carbon dioxide bubbles rising in water
Authors: Bowman C. W. , Johnson A. I. 
Published: February 2011

AbstractContinuous phase mass transfer coefficients have been measured for carbon dioxide bubbles rising in water. A procedure was developed for systematically studying the effect of the three variables: bubble volume, formation frequency, and seal height.The mass transfer coefficient was independent of bubble volume, increased 35% with a ten‐fold increase in frequency and varied only 8% over a 30 cm. range in seal height. The data, extrapolated to zero frequency, agreed well with the single bubble study of Hammerton and Garner. The Higbie equation predicted results very close to those obtained here but was not too successful in explaining the effect of bubble size or frequency.The average mass transfer coefficient is about four times that for a solid particle as reported by Akselrud; this enhancement is attributed to internal circulation. Surface absorption rates were determined as a function of bubble frequency. New data has also been presented on the factors which control frequency, velocity of rise, and bubble shape. A partial correlation was developed relating bubble frequency to chamber volume.
Axial thermal conductivities in packed beds
Authors: Bischoff Kenneth B. 
Published: February 2011

AbstractRadial thermal conductivities in packed beds have been extensively studied and correlated, but there is little published work on axial conductivities. The data on axial conductivities that is available is limited to low flow rates because of measurement difficulties at high flow rates. In this paper, a method is presented for estimating the values of axial thermal conductivities at high flow rates from the existing data on radial thermal conductivities. The necessity for considering packed bed axial conduction in design work can be determined from these results.
Resolution of the operating variables of a small hydrocyclone
Authors: Pilgrim R. F. , Ingraham T. R. 
Published: February 2011

AbstractApplication of dimensional analysis and experiment to the operation of a hydrocyclone yielded an equation of the form: magnified imageThis equation shows that the volume throughput Q is a function of the pressure differential P, the density δ and the viscosity μ of the medium. The constant K1 and the coefficients of the pressure differential, density and viscosity were shown by statistical analysis to be relatively simple functions of the dimensions of the body and orifices of small glass hydrocyclones used with liquid media.
Gas diffusion with chemical reaction in porous solids
Authors: Scott D. S. 
Published: February 2011

AbstractThe nature of the diffusive mechanisms in the pore spaces of catalytic solids is briefly reviewed, and the effective diffusion coefficient is discussed. Binary diffusion equations, including a general expression covering all modes of diffusion, are given. Using the general diffusion equation together with first order reaction, a solution for isothermal conditions and slab type geometry is found, applicable to all modes of diffusion, with or without volume change on reaction. The extension of this solution to other pellet shapes and to second order reactions is discussed.The measurement of diffusion rates in porous solids is considered, and the interpretation of such measurements in terms of effective diffusion coefficients is clarified by means of the general diffusion equation. Methods of determining effective diffusion coefficients other than by direct diffusion measurements are discussed, and, in particular, a forced flow technique is reviewed.
Batch processing plants
Authors: Thomas L. R. 
Published: February 2011

AbstractThe profitability of small‐scale chemical operations is a subject of wide interest in Canada because of the problems arising from a small and spread out domestic market. In this paper the author discusses the place of “Batch Processing Plants” within this context, emphasizing those features having a bearing on the flexibility of operation and economics of batch plants, viz:‐reaction yields, flow interruptions, plant complexity, ease of plant expansion and multipurpose applications. Since this paper is of a general review nature, discussion of the more detailed aspects of batch versus continuous processing, such as reaction kinetics, tubular reactors, process control, etc., are not included since each is a subject in itself.The author concludes that, in the circumstances applying to the Canadian chemical industry today, greater consideration should be given to the use of batch processing plants at the appropriate production levels because of their flexibility for development and multi‐purpose applications and relatively low capital cost.
The vapor phase hydration of acetylene
Authors: Szonyi A. J. , Graydon W. F. 
Published: February 2011

AbstractA study has been made of the kinetics of the vapor‐phase hydration of acetylene over a zinc phosphate‐phosphoric acid‐activated carbon catalyst. Rates of acetylene hydration were measured in a fixed bed flow reactor operated at low conversions. The majority of the data was obtained at 350°C. The amounts of acetylene hydrated were determined by analyzing the products for acetaldehyde, crotonaldehyde and acetic acid. The catalyst activity diminished with increasing process time.The reaction rate data obtained at low conversions of acetylene were correlated by an empirical equation and a tentative mechanism suggested which is consistent with this equation.The data obtained in the low conversion (differential) reactor have been compared to the data obtained using a fixed bed flow reactor operated at high conversions, using the integrated form of the rate equation.
Optimum process design for a heat exchanger type of reactor: Application of a Bi‐variant function generator to an analog solution
Authors: Kubota Hiroshi 
Published: February 2011

AbstractThe optimum process design for a heat exchanger type of reactor is derived through a selection of process conditions which give the minimum volume of reactor for a fixed conversion of a particular reactant. The method is illustrated by calculations on an ammonia synthesis reactor using an analog computer equipped with a bi‐variant function generator.
Simultaneous gas absorption and liquid phase chemical reaction in an agitated vessel
Authors: Vassilatos G. , Trass O. , Johnson A. I. 
Published: February 2011

AbstractAbsorption rates of pure carbon dioxide by aqueous ammonia and sodium hydroxide solutions were measured using a small agitated vessel. The interfacial area was known and the stirring rate was kept constant.The rates were compared with those predicted by the film, the penetration, and the Kishinevsky models for intraphase mass transfer. The film theory showed the best agreement.
Numerical analysis of stratified laminar flow of two immiscible Newtonian liquids in a circular pipe
Authors: Gemmell Alan R. , Epstein Norman 
Published: February 2011

AbstractComplete numerical solutions were determined in dimensionless form, of the velocity profiles for cocurrent laminar stratified flow of two immiscible Newtonian liquids in a circular pipe, for viscosity ratios of 1, 10, 100 and 1000, at eight positions of the horizontal liquid‐liquid interface, which was incorporated into the relaxation procedure by a twodimensional finite difference method described by D. N. de G. Allen. The velocity profiles were used to compute the theoretical hold‐up ratios, pressure gradient reduction (or volumetric flow rate enhancement) factors and power reduction factors for the various viscosity ratios and interface positions; the maximum reduction factors for each viscosity ratio; and the input volume fractions of the two liquids corresponding to each of the above.The theoretical results for laminar flow were compared with experimental data in the literature, in particular those of Russell, Hodgson and Govier for the horizontal flow of a mineral oil and water (viscosity ratio = 20.1) in a circular pipe. Good agreement was obtained for both hold‐up and pressure drop data when both water and oil were in laminar flow. As the water entered the transitional and turbulent regions, however, a deviation between the experimental and the computed results developed, the deviation increasing in the anticipated direction as the Reynolds number of the water increased.
Spouted bed drier
Authors: Peterson W. S. 
Published: February 2011

AbstractThe first commercial spouted bed driers have been installed in Canada and one has been used to dry three types of peas, lentils and flax. The data obtained from this drier have been compared and correlated with previous drying studies in various laboratory spouted bed driers. An empirical relationship between solids temperature and other variables has been obtained:

where TK and TA are respectively the particle and inlet air temperature, dgm the particle diameter, Do the column diameter, F the feed rate and Mf the feed moisture content.High drying capacity was achieved through the use of high air temperatures with the result that a two foot diameter spouted bed heater (plus cooler) dried almost two tons per hour of peas through 8.8% moisture range. No damage was evident in materials dried.
Performance characteristics of a 12 in. Diameter sieve plate
Authors: Harris I. J. , Roper G. H. 
Published: February 2011

AbstractThe hydraulic characteristics of a 12 in. diameter sieve plate have been studied and data are presented for plate pressure drop, clear liquid head on the plate and foam height, measured over a range of gas and liquid phase rates and outlet weir heights.The mass transfer performance of the plate, as expressed in terms of an equivalent number of transfer units, was measured for conditions of both gas and liquid film control over a similar range of operating variables. The number of transfer units are shown to be directly related to the appropriate phase contact time on the plate.The equations developed by A.I.Ch.E., to correct for back mixing effects on the plate efficiency, have been found to under‐estimate the degree of mixing on the plate used, and hence predict lower liquid efficiencies than might be expected from a comparison with literature values.
Critical temperatures and pressures of substances from vapor pressure data
Authors: Stiel Leonard I. , Thodos George 
Published: February 2011

AbstractA method has been developed for the prediction of the critical temperature and pressure of any pure substance from its reliable vapor pressure data. These data are used to determine the constants A, B, C, and D of the substance for the Frost‐Kalwarf equation. The critical temperature of the substance is then calculated from the constants B and C. The critical pressure is calculated by substituting the values of A, B, C, and the calculated critical temperature into the Frost‐Kalwarf equation applied at the critical point.This approach was used to calculate critical constants for 64 non‐hydrogen bonding substances of all types which were primarily hydrocarbons. An average deviation of 0.59% resulted for the critical temperature and 3.18% for the critical pressure.
Radioactive factors in water pollution
Authors: Guthrie J. E. 
Published: February 2011

AbstractThis paper is primarily concerned with the introduction of radionuclides into bodies of water as a result of nuclear reactor operations. When radioactive materials are dispersed in surface waters, several factors such as water usage and biological concentration in human food chains must be considered. Individual radiochemical determinations of the potentially hazardous nuclides in the water, particularly Sr‐90 are desirable.The off‐site water monitoring program at the Chalk River Plant of Atomic Energy of Canada is outlined.
Heat transfer to clouds of particles
Authors: Themelis N. J. , Gauvin W. H. 
Published: February 2011

AbstractAn analysis was made of the rate of heat transfer by convection, radiation, and chemical reaction to a dispersion of particles in a non‐absorbing gas. The gas‐solids suspension was subjected to co‐gravitational flow at low Reynolds Numbers (50–500) through a cylindrical reactor, the wall of which was maintained at a uniform temperature (400–900°C). The rate of heat transfer by convection from the wall to the gas was determined experimentally. The differential equations were solved on an IBM‐650 digital computer, for the reduction of iron oxide particles (40 to 100 microns) by hydrogen. The program output recorded the particle residence time and corresponding values of gas and particle temperatures, length of reactor travelled, percent reduction, and individual rates of heat transfer to the particle by convection, radiation and chemical reaction. Experimental measurements in an electrically‐heated, 4.4‐in. i.d. × 8.5 ft. long stainless steel reactor verified the calculated prediction that the particle temperature should at all time be nearly equal to that of the gas.
Isobaric vapor‐liquid equilibrium data for binary systems
Authors: Nagata Isamu 
Published: February 2011

AbstractVapor‐liquid equilibrium data at atmospheric pressure are reported for the systems: 2‐butanone‐2‐propanol, chloroform‐2‐propanol, ethyl acetate‐2‐butanone, and methyl acetate‐2‐propanol. The experimental results are correlated by two typical methods in the literature.
Fluorescence effects in ion exchange resins
Authors: Flint T. R. , Eichholz G. G. 
Published: February 2011

AbstractFluorescence under ultraviolet illumination has been observed in anion and cation exchange resins when in the unloaded state. This fluorescence decreases rapidly in intensity as the resin is loaded and this process has been shown to offer a practical method for controlling the loading and elution cycles in ion exchange operations.The relative effectiveness of different resins and various ions on this fluorescence quenching process has been determined and some correlation has been found between quenching efficiency and ionization potential of the elements. The measurements have shown adequate stability and reproducibility for industrial control applications.
A theoretical and experimental investigation of fiber suspension drainage in the turbulent regime: Part 2. An experimental study of turbulent drainage using model nylon fibers with application to practical papermaking suspensions
Authors: Meadley C. K. 
Published: February 2011

AbstractResults of drainage experiments using a laboratory hand sheet machine and model nylon fiber suspensions are presented and discussed. The discussion is concerned with the measurement of two general parameters of the turbulent drainage theory, previously published as Part I of this study, and the ability of the theory using these measured values to predict nylon suspension drainage characteristics over a wide range of conditions. In addition, results of drainage tests with groundwood and sulphite fractionated stocks are discussed in terms of the application of this theory to natural fiber suspensions.In general, it was found that, in the realm of practical papermaking represented by high machine speeds, drainage resistance is proportional to the square of the filtration rate and the turbulent pressure drop concept applies.
Settling velocities of coal particles
Authors: Moreland C. 
Published: February 2011

AbstractSettling velocities of coal particles falling by gravity in a mineral oil have been measured for particle sizes ranging from 80 to 2,000 microns, at slurry porosities of between 0.6 and 1.0. Velocities for the latter figure correspond to the terminal velocities of single particles.The terminal velocities were found to be within 25% of the predicted values for spheres and could, for Reynolds numbers less than 0.2, be related to the particle size (d) by the equation V = Kd2,15.The settling velocities of the slurries, which were all in the laminar region, are shown to be related to the slurry porosity (ε) by the theoretical equation of Maude and Whitmore, namely V = V, where Vo is the terminal velocity. Values of n between 6.5 and 7.5 were found.
Channels and chains of bubbles in gas fluidized beds
Authors: Botterill J. S. M. , Bloore P. D. 
Published: February 2011

AbstractThe disturbance caused by the development of channels and chains of bubbles through gas fluidized beds has been studied using a local gas injection technique. The average disturbance formed was measured using a γ‐radiation absorption technique supplemented by pressure drop and bed expansion measurements.The channels or close chains of bubbles were found to persist through the bed to a height dependent on bed conditions and the energy of the gas flow through the disturbance. The disturbance then degenerated into larger bubbles which tended to coalesce, grow and become more widely separated. The rate of increase of disturbance diameter was inversely proportional to the square of the estimated gas flow velocity through the disturbance. Bubble spacing increased through the upper elements of the disturbance. It was concluded that the resistance to flow of escape gas through this part of the chain was increased and that this caused an increase in gas residence time corresponding to the observed increase in resident void volume in the upper elements of the disturbance.The channel or close chain of bubbles provided a low resistance path by which gas readily escaped. In shallow beds at incipient fluidization the path readily reached through to the bed surface and reactant gasses may largely bypass the bed under these conditions and the bed cease to be fluidized.
The pipeline flow of coal‐in‐oil suspensions
Authors: Berkowitz N. , Moreland C. , Round G. F. 
Published: February 2011

AbstractThe flow behavior of coal‐in‐oil suspensions at velocities up to ca. 20 ft./sec. has been investigated in a one‐inch d. experimental pipeline. Detailed data are presented for a bituminous and a subbituminous coal (effective size < 700 microns) entrained in two oils (μ = 5.6 and 46.7 ep. at 25°C. respectively); coal concentrations in the suspensions ranged > 70% w/w.At flow velocities greater than 2 ft./sec. and coal concentrations below 50% w/w, the suspensions were found to move as relatively homogeneous (or quasi‐homogeneous) fluids, and pressure gradients followed the usual friction factor/Reynolds number relationship. But no satisfactory correlations could be established for flow at < 2 ft./sec., which is influenced by significant settling, or for the behavior of suspensions containing > 50% w/w coal. In the latter case, laminar flow obtained at all velocities and the suspended particles tended to concentrate near the pipe axis (and to move along it as a definite ‘core'’. One effect of this phenomenon is a substantial reduction in the apparent viscosity of the suspension.
Experimental investigation of natural convection heat transfer in confined space for non‐Newtonian fluid
Authors: Pierre Carl St. , Tien Chi 
Published: February 2011

AbstractExperimental work was carried out for the study of convection heat transfer of fluid confined between two horizontal plates. The rheological properties of the fluid can be described by Ostwald ‐ de Wael model. The results as expressed in terms of dimensionless groups were successfully correlated by the following expression:

The Rayleigh and Prandtl numbers are defined in the generalized sense with the flow behavior index, N, being considered as a correcting factor for the deviation from Newtonian behavior.
Optimal design of a continuous stirred‐tank reactor by a gradient method
Authors: Reed Lawrence A. , Stevens William F. 
Published: February 2011

AbstractThe design of a continuous stirred‐tank reactor, used in the formation of allyl chloride from chlorine and propylene, was optimized by a gradient method. Four process variables were considered: Reaction temperature, pressure, feed composition, and “pseudo” residence time (ratio of reactor volume to molar feed rate). In addition to the primary reaction, a secondary and a consecutive reaction were included in the process model.Sensitivity analyses revealed that 5% errors in the reaction rate constants produced only very slight changes in the optimal design. In addition, it was found that the profit from the operating reactor was a strong function of feed composition and reaction temperature and a relatively weak function of pressure and “pseudo” residence time.A program was developed for the IBM 709 computer by which the machine made all appropriate decisions and calculations in finding the optimal design and carrying out the sensitivity analyses.
Studies of the critical heat‐flux for some binary mixtures and their components
Authors: Carne M. 
Published: February 2011

AbstractA pool boiler and a forced convection loop used for studying critical heat fluxes in binary mixtures are described. The geometry of the test element is shown to be an important variable in pool boiling experiments, affecting both absolute flux values and the variation with composition. Data given for AC and DC power supplies show that the critical heat flux is relatively unaffected by the power supply source.Empirical equations of the form (Q/A) c = const. Va ΔTbsub are given for benzene, toluene and acetone, which correlate the forced convection subcooled data with average deviations of 3.1%, 5.0% and 5.1% respectively.Forced convection subcooled data are given for the systems benzene‐toluene and acetone‐toluene showing the effect of composition on critical heat flux.It is concluded that, at forced convection subcooled conditions in certain concentration ranges, binary mixtures may exhibit critical heat fluxes which are higher than for either of the pure components. In this respect loop experiments are analogous to pool boiling ones. However, extrapolation from pool boiling experiments to loop conditions does not appear to be feasible under the present test conditions.
Viscous flow around fluid spheres at intermediate reynolds numbers (II)
Authors: Hamielec A. E. , Storey S. H. , Whitehead J. M. 
Published: February 2011

AbstractApproximate velocity profiles have been predicted for laminar, incompressible flow around solid and fluid spheres for Reynolds numbers up to several thousand. The accuracy of the predicted profiles for solid spheres has been tested in three ways. Drag coefficients, flow‐separation angles and forced‐convection transfer rates calculated from these profiles have been compared with experimental data for solid or rigid spheres. The predicted quantities oscillate about the experimental data as the Reynolds number is increased. Cross‐over points occur at Reynolds numbers of about 20, 100 and 500. The velocity profiles for fluid spheres are of little practical value above Reynolds numbers of several hundred as drop or bubble deformation is significant.Drag coefficient data for solid spheres, liquid drops and gas bubbles showing the effect of dispersed‐phase viscosity on total drag are presented. These data are correlated over the Reynolds number range, 10–100 with a viscosity‐ratio correction factor which was derived theoretically.