bluuebunny/crossref_metadata_2025_split huggingface dataset:
Predicting the required liquid throughput from the capsule velocity and capsule pressure gradient in capsule pipelines
Authors: Kruyer Jan , Ellis H. S. 
Published: March 2009

AbstractA model has been developed describing the relationship between the capsule velocity, the capsule pressure gradient and the bulk velocity. It allows the prediction of the bulk velocity when both the capsule velocity and the capsule pressure gradient are known and thus enables the calculation of the amount of liquid required to move a given quantity of solids. It also allows the prediction of the capsule pressure gradient when both the capsule velocity and the bulk velocity are known, but the measurement of these velocities must be very accurate before the capsule pressure gradient can be predicted to a reasonable accuracy. A Reynolds number developed for the model indicates whether the liquid surrounding the capsules is in laminar flow (Rec > 1000) or inturbulent flow Reo > 1000).
Peak heat fluxes on thin horizontal ribbons in submerged water jets
Authors: Andrews D. G. , Rao P. K. Mohan 
Published: March 2009

AbstractThis paper reports experimental observations on peak (critical) heat fluxes on stainless steel ribbons exposed to flow currents under submerged distilled water jets at subcooled and saturated conditions at near atmospheric pressures. A theoretical correlation is proposed based on certain modifications to the treatment of pool boiling hydrodynamic theory.
Modelling of liquid‐liquid extraction columns: Use of published model correlations in design
Authors: Korchinsky W. J. 
Published: March 2009

AbstractDesign of several liquid‐liquid extraction columns — packed, pulsed‐packed, pulsed‐plate, Oldshue‐Rushton columns and the rotating disc contactor — was attempted utilizing available correlations for drop size, holdup of dispersed phase, flooding velocities, mass transfer coefficients and axial mixing coefficients. Correlations in many cases were vaguely defined and often based on very limited data. Results indicated that for given flow rates and extraction efficiency, the height of a packed or Oldshue‐Rushton column must be considerably greater than the predicted minimum heights of the other three columns, which were comparable considering the limited data utilized in the developed correlations. A critical evaluation of the correlations should be carried out to guide the further experimental effort required to confirm the utility of the axial dispersion model in liquid‐liquid extraction column design. Extension of the theory to include drop size variation is highly desirable.
Rate models for cyclic separation processes — comparison with experimental results in cyclic electrodialysis
Authors: Thompson D. W. , Bass D. , Abu‐Goukh M. E. 
Published: March 2009

AbstractTwo rate models for cyclic separation processes are discussed in terms of their applicability to cyclic electrodialysis. Both the constant‐rate model and the concentration‐dependent‐rate model predict little or no separation when the fluid displacement cycle is continuous and in phase with a continuous electric current cycle. Modification of the cycles by periodically interrupting either the electric current or the fluid flow, or by out‐of‐phase operation, leads to large separation. These observations are shown to be in agreement with previously published experimental results.
Liquid‐liquid separations in a conventional hydrocyclone
Authors: Sheng H. P. , Welker J. R. , Sliepcevich C. M. 
Published: March 2009

AbstractThe performance of a conventional hydrocyclone for separation of immiscible liquids was investigated experimentally. The results are particularly useful for evaluation of multi‐cyclone process design of same system. The effect of materials of constructions of the hydrocyclone on the separation efficiency was also tested. Significant differences in performance were noted depending on the preferential wettability characteristics of the solid surfaces for the liquids being separated.
Rate constants of elementary steps by pulse technique
Authors: Hattori Tadashi , Murakami Yuichi 
Published: March 2009

AbstractTwo methods for measuring the rate constants of the elementary steps by the pulse technique are proposed. The first gives the adsorption and the desorption rate constants from the retention time and the half width of the chromatographic peak, and was applied to the adsorption of benzene on HY and CaY zeolites. The second gives the surface reaction rate constant and the desorption rate constant of the reactant from the peak of the product which is not adsorbed on the catalyst surface. The method was applied to the cracking of cumene on HY and CaY.
Prediction of heats of mixing of liquid mixtures by an analytical group solution model
Authors: Nguyen T. H. , Ratcliff G. A. 
Published: March 2009

AbstractAn analytical group solution model has been developed for the prediction of heats of mixing of liquid mixtures using the Wilson equation. This procedure obviates some of the limitations and inaccuracies of the previous model, and is well suited to computer calculation. It was tested for a wide range of alcohol/alkane mixtures and gives good results.The group Wilson parameters were generated from experimental data for methylene/hydroxyl mixtures at 15°C to 55°C. At temperatures within or close to this range, these group parameters allow prediction of heats of mixing of binary or multicomponent mixtures containing these two groups. No experimental data are required.
Some Observations on the motion of elongated bubbles in horizontal pipes
Authors: Aziz K. , Gregory G. A. , Nicholson M. 
Published: March 2009

AbstractResults of a study of the flow of air‐oil mixtures in the elongated bubble flow pattern are presented, based on experiments conducted in a 1.014 inch diameter horizontal pipe. It is demonstrated that several well defined and reproducible sub‐regimes actually exist within the flow pattern usually designated as elongated bubble flow. Some previously unreported interrelationships between various measured parameters are noted and discussed. The experimental data are also used to test several existing correlations for the prediction of pressure drop and holdup in this flow regime.
Application of porous media models to the study of deep bed filtration
Authors: Payatakes A. C. , Rajagopalan R. , Tien Chi 
Published: March 2009

AbstractTwo porous media models — capillaric and Brinkman — were used for the study of deep bed filtration and to calculate the filter coefficient and the pressure drop increase during the course of filtration.The filter coefficient was estimated with trajectory calculations which determine the path of particulate matters as they pass through the filter. A number of relevant forces were included and their effects determined. The Brinkman model was found to give good agreement with experimental results and the filter coefficients based on capillaric model were approximately one to two orders of magnitude lower than experimental data.Both models fail to give reasonable estimates on the pressure drop increase and the discrepancies between the model and the experimental values were two to three orders of magnitude. This is largely due to the failure of the models to distinguish the different roles played by the filter grains and by the particulate matters retained. The filter grains constitute a matrix of passages as conduits for the liquid flow, and the deposited particulate matters act primarily to modify these flow passages (i.e. to restrict the flow). Such a distinction is however not possible with the use of these models.
Axial dispersion in a pulsed plate column
Authors: Baird M. H. I. 
Published: March 2009

AbstractA technique involving the indicator colour change in an acidbase reaction has been used to measure axial dispersion coefficients in a 15 cm diameter pulsed column. Data have been obtained mainly for single phase (aqueous) flow with two different types of plate at two different spacings. With coarsely perforated plates, the dispersion coefficient is proportional to (amplitude)2 times frequency, but semicircular unperforated baffle plates show a dependence on amplitude times frequency. These results are critically compared with published data, and two types of flow regime for axial dispersion are indicated.
Catalytic reduction of nitric oxide in the presence of oxygen in low concentration high velocity gas streams
Authors: Lamb A. , Tollefson E. L. 
Published: March 2009

AbstractA small fixed‐bed catalytic reactor and a gas chromatographic analytical method were used to investigate the effects of oxygen on nitric oxide reduction by hydrogen over metal alloys. This work follows similar investigations, previously reported, into the reduction of nitric oxide with hydrogen in the absence of oxygen. The rate of oxygen consumption was directly proportional to hydrogen concentration but independent of oxygen concentration, at oxygen and hydrogen partial pressures of 4 — 7 × 10−3 atm., and 1 — 11 × 10−3 atm., respectively, and space velocities of 43,000 – 45,000 hr−3. The activation energy for Monel* alloy was 8.8 kcals* g* mole−1 over a temperature range 347 – 502°CIn comparing Monel and brass catalysts some selectivity in the reduction of nitric oxide in the presence of oxygen was observed. Depending on the conditions to which Monel has been subjected, its activity at a given temperature was found to vary with time from one level to another.
Measurement of total pressures for ethylene — propane mixtures
Authors: Elshayal I. M. , Lu B. C. ‐Y. 
Published: March 2009

AbstractIsothermal P‐x data for the binary system ethylene‐propane were measured at four temperatures by means of a total pressure apparatus. Equilibrium vapor compositions were calculated with the supporting properties obtained from the Clausius Equation of state. In the calculation, the parameters of the Clausius Equation were considered to be temperature‐dependent. The validity of the apparatus and the proposed method of calculation was established by comparing satisfactorily phase equilibrium values obtained in this study with those reported in the literature for the binary systems argon‐nitrogen and argon‐methane. In addition, several vapor compositions were also determined experimentally for the binary system ethylene‐propane to confirm the accuracy of the calculated results.
The area affected by oil spills on land
Authors: Mackay D. , Mohtadi M. 
Published: March 2009

AbstractData have been compiled and analysed on the volume and area of 53 oil spills on land in Alberta. Comparable data are presented for smaller experimental spills in the Mackenzie Valley, North West Territories. From these spill data and consideration of the flow characteristics of oil on the permeable terrain of the Mackenzie Valley, an equation is derived to predict the likely area affected by an oil spill from the proposed Mackcnzic Valley Oil Pipeline, namely:‐Spill Area (m2) = 53.5( Volume (m3) )0.89
The identification of residence time models by reacting tracer experiments
Authors: Parimi K. , Harris T. R. 
Published: March 2009

AbstractIt has been shown that the steady‐state conversion of tracers which react with nonlinear kinetics (NLRT) may be used to differentiate complete mixing from macro‐fluid behavior. This paper presents the results of theoretical and experimental studies which have demonstrated that the discriminatory power of NLRT techniques may be greatly increased if unsteady‐state pulse tests with reacting tracers are used instead of steady‐state conversion experiments. The method is shown to be sufficiently sensitive to differentiate among models of mixing which describe the results of inert tracer experiments with equal accuracy. The method was used to identify the position of a plug‐flow element in a plug‐flow mixing‐cell network and to differentiate between a Taylor dispersion system and a plug‐flow mixing‐cell network.
Solubility of propane in isomers of hexane and other non‐polar solvents
Authors: Fleury D. , Hayduk W. 
Published: March 2009

AbstractSolubilities of propane at atmospheric pressure and for temperatures ranging from —15°C to 70°C are reported for a variety of solvents including hexane and the branch‐chained hexane isomers, for cyclohexane, perfluorohexane, benzene, ethylbenzene, metaxylene, carbon tetrachloride and carbon disulfide. These data, along with data from the literature, are used in comparing solubility behavior of propane and the other paraffin gases in a range of solvents.While predictions of gas solubilities even in non‐polar solvents are still somewhat uncertain, it appears possible to estimate the solubilities of methane, ethane, propane or butane by extrapolation of known solubilities of these gases in a range of solvents. It is also possible to predict the temperature coefficient of solubility in solvents, such as benzene, which yield regular solutions.
The electroreduction of oxygen to hydrogen peroxide on fluidized cathodes
Authors: Oloman Colin , Watkinson A. Paul 
Published: March 2009

AbstractThe cathodic reduction of oxygen to hydrogen peroxide on fluidized beds of graphite has been studied. The cathodes were fluidized by an oxygen saturated solution of 0.1M NaOH, or by the simultaneous introduction of oxygen gas and hydroxide solution. With increasing current density, the current efficiency always decreased while the product peroxide concentration went through a maximum. In the two‐phase system the maximum peroxide concentration increased with bed height. Both current efficiency and the rate of peroxide production generally decreased with catholyte flowrate. For the three‐phase fluidized cathode the rate of peroxide production and the current efficiency increased with both catholyte and oxygen flowrate. Possible rate controlling steps are discussed. Current densities for both two phase and three phase fluidized beds were too low to be of commercial use.
Extraction of phenol from water with mixed solvents
Authors: Medir M. , Mackay D. 
Published: March 2009

AbstractDistribution coefficient data ate presented for phenol at 25°C between water and nine mixed solvents. The binary solvent mixtures were n‐octane with n‐hexanol‐l, n‐octanol‐l and n‐decanol‐l; n‐octanol‐l with benzene carbontetrachloride, cyclo‐hexane, kerosene and butyl acetate; and n‐butyl acetate with benzene. All alcohol mixtures exhibited a positive deviation from linearity in distribution co‐efficient, maxima being obtained for mixtures of n‐octanol‐l with n‐butyl acetate and benzene. The data are correlated empirically and the nature of the chemical associations discussed. Practical implications are that esteralcohol mixtures may be the preferred solvents for phenol extraction from water since these mixtures have distribution coefficients significantly greater than either pure solvent.
Heat transfer rate predictions in condensation on droplets from air‐steam mixtures
Authors: Kulic E. , Rhodes E. , Sullivan G. 
Published: March 2009

AbstractThis paper describes simulations of the combined heat and mass transfer to single water droplets falling freely in air‐steam mixtures. The effects of droplet size, initial velocity, and concentration of steam in the mixture are discussed. The results are to be used in the design synthesis of steam dousing chambers in which sprays containing droplets whose diameters range as high as 6 mm. are used.
Effect of high temperature treatment on the properties of fe‐mo oxide catalysts
Authors: Aruanno Jorge , Wanke Sieghard 
Published: March 2009

AbstractIn this study the structural and compositional changes that Fe‐Mo oxide catalysts undergo during treatment at elevated temperatures were investigated. Commercial and laboratory prepared catalysts were examined. The changes in catalyst properties were determined by low temperature nitrogen adsorption, scanning electron microscopy, X‐ray diffraction, X‐ray fluorescence and thermogravimetric analysis. The activities of the catalysts for the oxidation of methanol in air to formaldehyde were measured using an integral bed reactor.The results showed that treatment at elevated temperatures resulted in the growth and segregation of Fe2(Mo04)3 and Mo03 crystals resulting in a loss of specific surface area. The changes in specific activity can be explained in terms of molybdenum depletion from a molybdenum rich iron molybdate phase.
Effects of charge stock composition on the kinetic parameters in catalytic cracking
Authors: Pachovsky Roman A. , Wojciechowski Bohdan W. 
Published: March 2009

AbstractIt is shown that the addition of wax to a wax free neutral distillate has no synergistic effect on the initial rate constant for cracking. The initial rate constant is in fact found to be a linear function of the mole fraction of wax in the feed. At the same time it is found that the activation energy for the cracking of pure wax is ˜ 48 kcal/inole and is some 4 kcal/mole lower than the activation energy for the cracking of the wax free aromatics and cyclic aliphatics. We are therefore led to believe that the initial rate constant for the catalytic cracking of any mitxure of compounds is simply the sum of the individual rate constants weighted by their respective mole fractions.It is also shown that the introduction of wax into the wax free feed results in an increased apparent order of the overall reaction and in more rapid decay of catalyst activity.
Steady state and dynamic studies of a multi product chemical plant
Authors: Johnson A. I. , Lozada A. , Anvari M. , Stephanopoulos G. , Weng P. 
Published: March 2009

AbstractSteady state and dynamic behaviour studies of a fat hydrolysis plant for handling a variety of feeds to produce a range of fatty acids for detergents and soaps are presented. These include optimization techniques for the steady state. Alternate techniques for product change are presented, and simulated using a dynamic simulator. The computer systems used are modular.
Particle segregation in a fluidized bed
Authors: Chen J. L.‐P. , Keairns D. L. 
Published: March 2009

AbstractParticle segregation data at low gas velocity, near the minimum fluidizing velocity, are presented for particles of different size (150 to 2800 μm) and density (720 to 2800 kg/m3) in a fluidized bed. Phase diagrams similar to those of liquid‐solid systems are developed to present the results. The data were collected in a 100 mm diameter unit operating at pressures up to 660 kPa and a 114 mm diameter unit at atmospheric pressure.The particle segregation data were obtained to provide design and operating criteria for a two‐stage. i.e., an agglomerating combustor/gasifier and a devolatilizer/desulfurizer, fluidized bed coal gasification process to produce low heating‐value gas (890‐1350 K‐cal/m3) for power generation. The data indicate that the criteria for particle separation can be achieved if the operating gas velocity is close to the minimum fluidizing velocity of the dense particles, that is, agglomerated ash, and spent dolomite.
Corona‐induced autohesion of polyethylene: Dependence of bonding on frequency and power consumption in various gases
Authors: Stradal M. , Goring D. A. I. 
Published: March 2009

AbstractThe autohesion of polyethylene sheets was markedly improved by corona discharge treatments in oxygen, nitrogen, argon and helium. Equal bond strength was produced by an equal number of discharge cycles regardless of the time or frequency of application. At a given operating voltage the power consumed in a discharge rather than the chemical nature of a gas proved to be a factor controlling the enhancement of autohesion. The detrimental effect of the oxidation upon autohesion was noted after a prolonged treatment in an oxygen corona.
Experimental testing of the hydrodynamic collision model of fine particle flotation
Authors: Reay David , Ratcliff G. A. 
Published: March 2009

AbstractFlotation rates of glass beads and of latex particles have been measured as a function of particle size using very small bubbles. With glass beads the observed rate versus size relationship agreed quite well with the prediction of a simple hydrodynamic collision model, but that found with latex particles did not. It is suggested that electrical forces may have to be taken into account when the particles have a significant zeta potential. With both types of particle, the relationship between flotation rates measured at two different bubble sizes is consistent with the model's predictions.
Laminar natural heat transfer from an isothermal sphere to non‐newtonian fluids
Authors: Liew K. S. , Adelman M. 
Published: March 2009

AbstractAn experimental study of natural convection heat transfer conducted with water and thirteen aqueous polymer solutions obeying the power‐law model, varying in flow behavior index from 0.3 to 0.99, and consistency index between 10 and 5 × 103, showed that the behavior of these solutions justifies the theoretical treatment of this phenomenon proposed by Acrivos(10). The heat source was an internally electrically heated copper sphere, 5 inches in diameter, and designed to provide an isothermal surface.
Mass transfer from crystalline surfaces in a turbulent impinging jet part I. Transfer by erosion
Authors: Giralt Francesc , Trass Olev 
Published: March 2009

AbstractMechanical erosion from two crystalline coating materials, naphthalene and trans‐cinnamic acid, in submerged turbulent impinging jets of water has been studied. In the absence of diffusion, the observed erosion rates in the wall jet region vary linearly with wall shear stress. Threshold shear stress values below which erosion may be neglected have been defined for both coating materials. Erosion rates in the impingement region also depend on the shear stress which, depending on the crystalline grain size, may interact with pressure forces.
Non‐isothermal pressure‐drop in non‐newtonian laminar flow
Authors: Mahalingam R. , Coulson J. M. 
Published: March 2009

AbstractExperimentally‐measured pressure‐drop data are compared with analytical predictions for laminar flow of non‐Newtonian fluids in circular conduits, under constant wall heat flux boundary condition. The non‐Newtonian pseudoplastic solutions used in this study were aqueous solutions of Methocel® (0.75% – 2% w/w) and Carbopol 934® (0.15% – 0.50%). The heated section was 0.792″ i.d. × 1″ o.d. × 112.87″ long brass tube with an additional length of 68″ acting as the entrance length. The analytical predicitions on pressure drop have been based on numerically computed or analytically‐postulated temperature profiles. The mean deviation of the predicted values from the experimental values is of the order of ±8%.
Influence of fluid rheology on circulation, mixing and blending
Authors: Chavan V. V. , Ford D. E. , Arumugam M. 
Published: March 2009

AbstractThe measurements of the integral physical quantities such as circulation, mixing and blending times for helical screw impellers with the draught tube are presented in this paper. The influence of shear‐thinning and elastic properties of the liquids on these quantities are analysed both experimentally and theoretically.The overall circulation was found to be independent of the shear‐thinning character of the liquid. The influence of elasticity is considered in the light of the existing knowledge on sonic simple flow situations. A relation which incorporates the geometry of the mixer and the rheological properties of the liquid is proposed.The mixing and blending time results are analysed and related to the hydrodynamics using the laminar mixing approach of Mohr and his co‐workers. Although the analysis is approximate, it provides a useful tool in explaining the effects of rheology. It also suggests a way to estimate the blending times.