bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adsorption de colorants ioniques sur des fibres de laine carbonisees
Authors: Perineau Francis , Farag Karim , Molinier Jacques , Gaset Antoine 
Published: March 2009

AbstractThe study of the adsorption of an acid dye (AB‐80) and of a basic dye (BR‐22) has been carried out on charred woollen fibres, with a view to using that industrial waste material in the treatment of liquid effluents. The authors have first studied the dye diffusion; the diffusion of AB‐80 appeared much slower than that of BR‐22, due to the steric cumbersomeness of the AB‐80 molecule. As a result, the temperature effect on the diffusion, owing to its influence on the dye aggregation, was clearly more pronounced for AB‐80 than for BR‐22; that fact was confirmed by the determination of adsorption isotherms at different temperatures. Under favourable conditions, the curves indicated satisfactory adsorption values; as they were cither of type H (AB‐80) or L (Br‐22), they also indicated the efficiency of the aforesaid fibres in the treatment of slightly‐concentrated effluents. The above finding has been verified by a column treatment of an AB‐80 solution; it then showed the very strong influence of the contact time as well as a wall effect on the effluent purification. In the study conclusion, the results obtained in the treatment of an industrial effluent in a stirred reactor are presented.
Leaching in a bubble‐column slurry reactor
Authors: Reilly I. G. , Scott D. S. , Abou‐El‐Hassan M. 
Published: March 2009

AbstractExperimental leaching runs were carried out in a continuous concurrent laboratory size bubble column 5.2 cm in internal diameter and 2.90 m tall. The system studied was the dissolution of a synthetic covellite (CuS) in ammoniacal solution in the presence of pure oxygen. Behaviour of the column with respect to gas holdup and solids concentration profiles was measured without reaction by using nitrogen in place of oxygen. Gas holdup values were in agreement with literature results. However, solids concentration profiles for the mixed particle size solid used were of a more complex nature than those obtained for uniformly sized solids.Conversions obtained at various temperatures and gas and liquid velocities were analyzed in terms of the estimated rates of the individual rate processes occurring. From these results, gas absorption rate was clearly the controlling mechanism at high temperatures, and surface chemical reaction rate was controlling at low temperatures. Hence, the rate controlling steps can be identified in bubble column reactors from currently available literature correlations, together with independent kinetic measurements.
Transient behavior of recycle reactor with consecutive reaction
Authors: Ido T. , Goto M. , Goto S. , Teshima H. 
Published: March 2009

AbstractExperimental and theoretical transient behavior of a recycle system were studied for a plug flow reactor with a mixing tank and a recycle line. The consecutive reaction chosen for experimental study was the hydrolysis of diethyl succinate through monoethyl succinate to succinic acid on a strong acid ion exchange resin at 50°C. Both realistic and simplified models were developed to simulate the transient behavior of the recycle system. The simplified model was more useful than the realistic model because analytical solutions could be obtained. The approach time to the steady state is presented for the recycle reactor.
Upgrading of delayed and fluid cokes from oil sand by desulfurization
Authors: Hall E. S. , Tollefson E. L. , George Z. M. , Schneider L. 
Published: March 2009

AbstractCalcination of delayed and fluid oil sand cokes with alkaline reagents at high sodium/sulfur ratios followed by leaching gave almost complete desulfurization in terms of gaseous combustion products. Use of smaller proportions of alkaline reagents with hydrodesulfurization at 650 to 850°C also resulted in extensive removal of sulfur as hydrogen sulfide.
Coating flows with interfacial air drag. A nonlinear theory
Authors: Nigam K. D. P. , Esmail M. N. 
Published: March 2009

AbstractThe problem of the coating flow of a Newtonian liquid under the influence of a contiguous air flow is considered. The effect of the air flow is simulated by a constant tangential viscous shearing, calculated as the average skin friction per unit area of a boundary layer air flow over a smooth flat plate. Predictions are obtained for the liquid flow characteristics in cases of cocurrent and countercurrent forced air flows. Significant changes in the liquid film thickness start to occur when the absolute value of a dimensionless shearing number, Tn, exceeds 0.01. This value is not sensitive to the other flow parameters. The study is limited to low and moderate liquid Reynolds numbers, when the surface tension forces have considerable to noticeable effect.
Studies of the behavior of disturbance waves in annular two‐phase flow
Authors: Nencini Franco , Andreussi Paolo 
Published: March 2009

AbstractDownward annular two‐phase flow (air‐water) has been examined experimentally. Statistical methods have been applied to calculate the flowrates associated with the hypothetical substrate flow and large wave flow. Agreement with actual Jiquid flowrates under varying gas flows is good. The constant thickness assumption is shown to give significant error. Main characteristics of large waves have also been determined.
Thermodynamics of ion exchange as an adsorption process
Authors: Novosad J. , Myers A. L. 
Published: March 2009

AbstractA thermodynamic description of adsorption from liquid solutions can be used as a basis for a rigorous thermodynamic treatment of ion exchange. Previous treatments were based upon the implicit assumption that the resin phase contains only fixed ionic groups and bound counter‐ions. However, porous ion exchangers can also absorb (or adsorb) the solvent and electrolytes dissolved in it. The observed selectivity of the exchanger depends upon the amount of solvent adsorbed, so that the definition of the boundary (Gibbs dividing surface) between the solid exchanger and the bulk liquid solution becomes important. Instead of the usual counter‐ion selectivity, the variable which describes the uptake of electrolyte is the equivalent of the surface excess. This paper is concerned with the definition and properties of this variable and with the development of an integral thermodynamic consistency test.On peut faire un traitement thermodynamique rigoureux de l'échange d'ions en utilisant une description thermodynamique de l'adsorption à partir de solutions liquides.
Mass transfer modelling for GS heavy water plants: Part 1: Point efficiency on GS sieve trays
Authors: Neuburg H. J. , Chuang K. T. 
Published: March 2009

AbstractA model that takes into account the gas‐phase and liquid‐phase resistance to mass transfer has been developed, where the overall mass transfer coefficient (KOGa) is expressed as a function of the equivalent Sauter‐mean bubble diameter. This parameter was back calculated from mass transfer measurements made at a pilot plant on single pass sieve trays of 0.311 m diameter. Hydraulic parameters were measured for these trays as well. Mean bubble diameters were then correlated as a function of active area F‐factor and dispersion height for various tray geometries, and these correlations are used to predict point efficiencies on production plant trays up to 8.5 m in diameter.
Optimum performance data for the leaching of roasted chalcopyrite concentrate in a jet contactor
Authors: Jain R. C. , Madhavan S. , Acharjee D. K. , Gupta P. Sen 
Published: March 2009

AbstractChalcopyrite concentrate has been roasted in a mullite tube furnace and the optimum temperature of roasting determined. The roasted concentrate has been leached with dilute sulphuric acid in a jet contactor. Optimum performance data for leaching, namely temperature, particle size, slurry concentration, acid concentration, nozzle diameter and effective contactor height have been obtained. For predicting the copper concentration in the leached solution, an expression based on a diffusion model has been derived and compared with the experimental data. It has been observed that at low values of mixed phase velocity, the agreement is good, but at high values, the variation is relatively larger.
Combustion of low heating value fuels and wastes in the spouted bed
Authors: Arbib H. A. , Levy A. 
Published: March 2009

AbstractIn a spouted bed burner, the flow‐maintained vortex of particles operates as a heat exchanger, preheating the incoming mixture without diluting it. This makes it a combustor especially attractive for incinerating low heating value fuels and wastes.Bench‐scale experimental studies were carried out to assess the ability of the spouted bed to burn efficiently poor fuels and waste materials in various aggregative states. The paper reports results of two series of experiments with gaseous and liquid fuel‐containing streams. High levels of hydrocarbon conversion and combustion efficiency were attained for mixtures that would not be combustible by other methods without an auxiliary fuel.
Computer control of holdup in a reciprocating plate extraction column
Authors: Taylor P. A. , Baird M. H. I. , Kusuma I. 
Published: March 2009

AbstractThis paper describes the application of computer control to a pilot scale (15 cm diameter) Reciprocating Plate Solvent Extraction Column. The system under investigation was kerosene dispersed in water without mass transfer between the phases. The control objective was the regulation and set point tracking of the holdup of the dispersed phase.Dynamic tests showed that the column was a non‐minimum phase, dead‐time process with asymmetric, non‐linear gains and time constants.Fixed parameter controllers of increasing complexity; PID, Dahlin algorithm, and minimum variance, were compared to an adaptive controller, the self tuning regulator. These controllers were applied in feedback and combined feedback‐feedforward configurations.
A one‐dimensional model of plug flow pneumatic conveying
Authors: Chan Shu‐Ming , Remple D. , Shook C. A. , Esmail M. N. 
Published: March 2009

AbstractA one‐dimensional model of pulse or plug flow is proposed. This type of flow is observed at high mass ratios of solids to gas and requires gas velocities orders of magnitude less than dilute phase systems.Plug stability criteria are examined by considering the axial interparticle stresses within single plugs and the effect of the radial transmission of these stresses on wall friction. Establishment of the fluid pressure gradient within the plug and the existence of a settled layer of solids in the interplug space are shown to be important requirements.These concepts are used in the formulation of an empirical pressure drop equation which is used in the correlation of experimental data. Comparison of predicted and experimental values is reasonable for the air‐sand system considered.The model should be of value in the planning and interpretation of future experimental studies.
Transfert de chaleur entre une couche fluidisee bidimensionnelle et une paroi
Authors: Granier M. , Riba J. P. , Couderc J. P. 
Published: March 2009

AbstractHeat transfer between a wall and a two‐dimensional fluidized bed has been studied. The fluidized bed remains isothermal for thicknesses as small as 8 mm, with significant values of the heat transfer coefficient up to the wall of the column.The bubbling properties in the two‐dimensional bed have been recorded using a rapid cine camera. These data have been used to test several heat transfer models. A convenient agreement has been obtained when taking into account a wall contact resistance term.
Evaluation et comparaison des parameters de la dispersion axiale dans les deux phases d'une colonne extraction à plateaux alternatifs
Authors: Bensalem A. , Steiner L. , Hartland S. 
Published: March 2009

AbstractThe impulse response technique for the injection of a tracer has been applied to both liquid phases in a pilot plant sized reciprocating plate extraction column of the type introduced by Karr. The responses obtained have been interpreted using the piston flow model, and employing three analysis techniques to determine the Péclet number, Pe, and the residence time, π, namely the moments method, the least‐squares method in the time and frequency domains and the Vergnes' method.The least‐square method was found to give the most coherent results, even for the dispersed phase, because this method is less sensitive to instrument drift (noise) than the two other methods.The piston flow model successfully described and correlated the longitudinal mixing in the continuous phase, and fairly well for the dispersed phase.
Kinetic parameter determination in monoculture and monosubstrate biological reactors
Authors: Rizzuti L. , Augugliaro V. , Dardanoni L. , Torregrossa M. V. 
Published: March 2009

AbstractThe kinetic parameters of a biological reactor, operating under monoculture and monosubstrate conditions, have been determined. Pure cultures of Nocardia corallina and Pseudomonas fluorescens species have been used with phenol as the only organic carbon source. The experimental runs have been carried out both in a batch and in a continuous stirred reactor.The batch results have been interpreted by zero order kinetics in phenol and first order kinetics in biomass. The kinetic‐constants have also been calculated. The activation energy has been determined only for the Nocardia species. Using this strain, the continuous reactor, working without biomass recycle, has confirmed the first order kinetics with respect to biomass.
The products of cumene cracking on an amorphous silica alumina
Authors: Marczewski M. , Wojciechowski B. W. 
Published: March 2009

AbstractA detailed analytical study of the products of cumene cracking over amorphous silica alumina shows that the mechanism of cracking over these catalysts is identical to that observed over crystalline LaY and HY at various levels of exchange. Additional analytical details are developed in this work and are used to elaborate on the previously proposed reaction network for this reaction. In particular we find that hydrogen and propane appear as secondary products in the cracking reaction network. We also find that within the limits of our measurement all the observed coke is formed from product propylene.
An explicit method of design of non‐isothermal tube‐wall reactor with volume change
Authors: Goyal S. K. , Esmail M. N. , Bakhshi N. N. 
Published: March 2009

AbstractAn analysis of a tube‐wall reactor with varying volume is considered under turbulent flow conditions for the case in which both the kinetic and diffusional resistances are important. The implicit molar flux expression is approximated by three successive approximations and the mass and energy balances are combined to obtain a single explicit design equation. This equation takes the form of a simple numerical integration which requires only physical and chemical properties of the inlet gas and reactor operating conditions. The method also predicts the temperature and heat flux along the reactor length. Comparison of the model predictions with a limited number of previous experimental results is good.
A fundamental study on recovery of copper with a cation exchange membrane: Part 1 — Ion exchange equilibria between cupric and hydrogen ions
Authors: Kojima Toshinori , Furusaki Shintaro , Takao Kenji , Miyauchi Terukatsu 
Published: March 2009

AbstractIt is possible to concentrate metal ion against the gradient of its concentration through a cation exchange membrane. The membrane has a high ion exchange capacity and is hydrophilic, therefore a rapid transfer rate of ions is expected.Ion exchange equilibrium data between cupric and hydrogen ions for sulfuric and nitric acid systems are obtained and analyzed quantitatively for concentrations of dissociated cupric and hydrogen ions.
A fundamental study on recovery of copper with a cation exchange membrane: Part 2 — Transfer rate of copper and hydrogen ion through a cation exchange membrane
Authors: Kojima Toshinori , Furusaki Shintaro , Saito Kyoichi 
Published: March 2009

AbstractTransfer rates of copper and hydrogen ion through a cation exchange membrane were measured experimentally for the systems of Cu/H‐SO4 and Cu/H‐NO3. Transfer rates of anions in the membrane were also measured, and they were negligible compared to those of the cations. Cupric ion and hydrogen ion transfer in a ratio of 1:2 and in opposite directions. The self‐diffusion coefficient of cupric ion in the membrane is obtained from the transfer rate of copper in high concentrations of sulfuric or nitric acid solutions using the equilibria data obtained in our previous work. The coefficient of the hydrogen ion is similarly obtained.
Liquefaction of coal by SRC‐II process: Part III: Reactivity of liquefaction products
Authors: Singh Chandra P. P. , Carr Norman L. 
Published: March 2009

AbstractData from experimental studies of the reactivities of SRC‐II liquefaction products, in the absence of coal, are analyzed. A general quantitative validation of the new kinetic model for SRC‐II coal liquefaction (Singh et al., 1981 a) is obtained by very good agreement between model predicted and measured yields. This shows that the new kinetic model provides a reasonable representation of the overall intrinsic process of SRC‐II coal liquefaction and hence, it can be used to explore the regions of process conditions far away from those obtained under normal SRC‐II operations.
Surface activity of foam fractions of a calcium lignosulphonate
Authors: Keirstead K. F. , Caverhill L. , De Kée D. 
Published: March 2009

AbstractSuccessive foam fractionation has been used to divide a processed calcium lignosulphonate into tractions differing appreciably in surface activity. Static surface tension has been measured by the de Nouy tensiometer and surface tension aging by the sessile bubble (photographic) method. The effect of concentration on surface tension has been determined. The effect of pH at 1% concentration on dynamic surface tension has been determined on freshly prepared solutions.
A new velocity profile model for turbulent pipe‐flow of power‐law fluids
Authors: Shenoy A. V. , Saini D. R. 
Published: March 2009

AbstractA new velocity profile model for turbulent flow of non‐Newtonian power‐law fluids in smooth pipes has been proposed, following the approach of Stein et al. (1980) for Newtonian fluids. The merit of the model, as different from all earlier works, lies in its ability to predict a zero velocity gradient at the centreline for all values of the pseudoplasticity index n. The predictions of the model when compared with the work of Bogue and Metzner (1963) have shown good agreement.
Estimation of vapor pressure from normal boiling point of hydrocarbons
Authors: Dutt N. V. K. 
Published: March 2009

AbstractThe Antoine equation is used to propose a simple method for the prediction of vapor pressure of hydrocarbons. This study on 218 compounds belonging to different homologous series revealed that (for each series of compounds): (i) the constant A of the Antoine relation is nearly the same for all the compounds, and (ii) the constants B and C can be related linearly to the normal boiling point. The result of the approach is Equation (7). Comparisons with the methods of Lee and Kesler (1980), and API Data Book (1978) show that the method described in this paper is a good alternative when normal boiling points are the only data available.On a employé l'équation d'Antoine pour proposer une méthode simple servant à prévoir la tension de vapeur des hydrocarbures. Cette étude, qui porte sur 218 composés appartenant à différentes séries homologues, a permis d'établir (pour chaque série de composés) les points suivants: (i) la constante A de l'équation d'Antoine est pratiquement la měme pour tous les composés; (ii) on peut relier linéairement les constantes B et C au point d'ébullition normal. L'équation (7) résulte de cette approche. Des comparaisons faites avec les méthodes de Lee et Kesler (1980) et avec les données que contient l'API Data Book indiquent que la méthode décrite peut ětre substituée avantageusement aux méthodes précitées, lorsque les points d'ébullition normaux sont les seules données disponibles.
Hydrodynamic transport of cylindrical capsules in a vertical pipeline
Authors: Latto B. , Chow K. W. 
Published: March 2009

AbstractData are presented on the flow phenomena associated with the hydraulic transport of right cylindrical capsules, having d/D and L/d ratios, and relative density in the range of 0.49 to 0.82, 4 to 14, and 1.15 to 2.7 respectively, in a 7.6 cm 1.D. vertical pipeline with flow Reynolds numbers up to 3.6 × 105. On the basis of the experimental results the effect of the individual pertinent variables which affect the velocity ratio Rv, pressure gradient ratio Rp and the unit energy requirement E for the capsule are discussed. Semi‐empirical correlations between the capsule velocity and the capsule gradient and the pertinent variables of the system are also presented.
Breakup of jets in power law non‐newtonianndashnewtonian liquid systems
Authors: Kitamura Yoshiro , Takahashi Teruo 
Published: March 2009

AbstractNon‐Newtonian effects on the breakup of jets into drops were experimentally studied for power law fluidNdashNewtonian systems under the condition of zero jet velocity relative to the continuous phase. While laminar breakup lengths of Newtonian jets in non‐Newtonian liquids agree with the prediction from the stability analysis for Newtonian systems, non‐Newtonian jets in Newtonian liquids are less stable than Newtonian jets. Experimental diameters of drops formed from jets in NewtonianNdashnon‐Newtonian and in non‐NewtonianNdashNewtonian systems are in good agreement with the prediction based on stability analysis for Newtonian systems.
Determination d'un champ de vitesses par anemometrie a films chauds dans des domaines a turbulence elevee application a des installations de decantation et d'Agitation
Authors: Gourdon C. , Et J. Costes , Domenech S. 
Published: March 2009

AbstractThe authors present a study of experimental methods which permit the determination of the turbulent hydrodynamic characteristics of the flow within settling and agitation units. The measurements have been made by thermal anemometry implying one and three hot films. The processing of the experimental data obtained on‐line in real time permits the average velocities, the turbulent fluctuations, the turbulent lengths and the dissipation rate to be obtained.
Dynamic analysis and simulation of a helium‐heated steam reformer
Authors: Miyasugi Takeshi , Kosaka Shinichi , Suzuki Akira 
Published: March 2009

AbstractThis paper deals with the dynamic characteristics of a helium‐heated heat‐exchanger type steam reformer with catalyst tubes of industrial size. A nonlinear dynamic model was developed based on algebraic and ordinary differential equations which describe material, component and energy balances. This model was numerically linearized around an operating point. In addition, an auto‐regressive model was obtained from experimental input‐output data in which the inputs were perturbed simultaneously using pseudo‐random binary sequences. Experimental data obtained by step and PRBS testing were used for comparison with the simulated responses. The comparison showed that the simulated responses agreed reasonably well with the experimental data.