JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
Print ISSN : 0021-9592
Volume 11 , Issue 4
Showing 1-16 articles out of 16 articles from the selected issue
  • A. G. POLLIN, VOJTECH FRIED
    1978 Volume 11 Issue 4 Pages 253-257
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
    A statistical theory of fluid mixtures is derived which is able to predict the excess enthalpy of binary liquid mixtures accurately from volumetric data. The treatment is a modification of the methodology developed by Flory and coworkers, in which the van der Waals energy-volume relationship is replaced by the more general expression, E=-a/Vm. The exponent m is postulated to be a fundamental property of each liquid component and the value of m for a binary mixture is assumed to be a volume fraction averaged function of the values of m for the individual components. The mixture is treated as being composed of two pseudocomponents whose potential energies and properties are not quite the same as those of the pure components from which they are derived. The theory permits the interaction energy between two like molecules in a mixture to vary with concentration.
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  • A. G. POLLIN, VOJTECH FRIED
    1978 Volume 11 Issue 4 Pages 258-264
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
    Values of the exponent m in the configurational energy expression, E=-Nrsη/2vm, have been obtained from enthalpy of mixing data for 17 non-polar and weakly polar liquids and several alcohols. With these pure component m values and volume fraction averaged mixture m values, the pseudo-2-fluid theory is successfully applied to fifty binary mixtures of nonpolar and weakly polar constituents and ten binary mixtures containing normal alcohols. Agreement between the excess enthalpies calculated from density data and observed HE values approaches the limits of experimental accuracy.
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  • ATSUSHI IKARI, YASUO HATATE, RYOKO DEGUCHI
    1978 Volume 11 Issue 4 Pages 265-270
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
    Vapor-liquid equilibria of water-ethanol system containing about 0.1% crotonaldehyde were measured at 1 atm. The equilibrium ratio of crotonaldehyde decreases rapidly with increasing concentration of ethanol and reaches unity when the mole fraction of ethanol is 0.98. Beyond this ethanol concentration it becomes lower than unity.
    The experiments of continuous distillation were carried out in a glass Oldershow-type column. The concentrations of the minor component in distillate and bottom were determined under various conditions. It is shown that in a range of higher concentration of ethanol, crotonaldehyde is difficult to remove by distillation.
    With some assumptions, a set of differential equations governing the behavior of ethanol and a minor component has been derived and solved numerically by the Hamming method.
    It is shown that the calculated curves are similar in shape to the observed ones. The model presented can be used to predict approximately the behavior of the minor component.
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  • YOSHISHIGE HAYASHI, EIJI HIRAI, SHUICHI HIGASHI
    1978 Volume 11 Issue 4 Pages 270-275
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
    Theoretical study of crossflow gas absorption accompanied by a second-order irreversible chemical reaction was performed by taking into account both gas- and liquid-phase resistances to absorption and this solution was compared with the results calculated in the previous paper2) on liquid-phase resistance.
    Using the theoretical solution proposed in this paper, one can examine how the chemical absorption rate is affected by the change of reactant concentration in the liquid phase or of solute gas composition in the gas phase, and can estimate the concentration profile of the solute gas at the gas-liquid interface.
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  • Eizo SADA, HIDEHIRO KUMAZAWA, YASUO YAMANAKA, ICHIBEI KUDO, TAKASHI KO ...
    1978 Volume 11 Issue 4 Pages 276-282
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
    The rates of single and simultaneous absorptions of dilute SO2 and NO in aqueous mixed solutions of NaClO2 and NaOH were measured at 25°C using a stirred vessel with a plain gas-liquid interface. In the SO2-NaClO2 system, the absorption rate exceeded the gas-film controlled rate, which implies the possibility of gas-phase oxidation of SO2 due to the evolved C1O2. In the SO2-(NaClO2+NaOH) system, the absorption rate agreed with that under gas-film controlled conditions. In the (SO2+NO)-(NaClO2+NaOH) system, the reduction of the NO absorption rate in the presence of SO2 substantially exceeded that evaluated through the decrease in interfacial concentration of NaClO2 and NaOH due to surface reaction with coexisting SO2. The rate of absorption of SO2 exceeded the gas-film controlled rate. The decomposition of NaClO2 proceeds to a greater degree during simultaneous absorption than the single absorption of SO2.
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  • SUSUMU FUKUSHIMA, ATSUO UYAMA, YOSHIRO YAMAGUCHI, EIJI TSUJI, SEIICHI ...
    1978 Volume 11 Issue 4 Pages 283-289
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
    Absorption rates of pure oxygen gas into sodium dithionite solution with sodium hydroxide were measured at 20 and 30°C in a laminar jet. Absorption rates were also measured under 0.315 to 4.0 atm of oxygen pressure in a continuous stirred tank.
    From analysis of the data on the basis of chemical absorption theory, the rate equation of chemical reaction for molecular oxygen A was obtained, where the molar ratio of sodium dithionite B to sodium hydroxide is lower than 1/2, as
    rA=k0, 1.9C0AC1.9B
    where
    k0, 1.9=(3.7±0.7)×1010 exp (-1.20×104RT) [(l/g-mole)0.9 sec-1]
    The absorption for the bubble stirred tank showed that the reaction orders for respective chemical species are reasonable.
    Furthermore, the homogeneous reaction assay in the continuous stirred tank established that this rate equation of chemical reaction is reasonable.
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  • NORIAKI KUBOTA, HIDEYUKI KARASAWA, TADAO KAWAKAMI
    1978 Volume 11 Issue 4 Pages 290-295
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
    Waiting times were measured at supercooling of 4, 8, 10 and 12°C respectively with agitation speeds of 150, 300 and 450 rpm. Critical supercooling was also measured in the range of cooling rates from 8.08 ×10-4 to 1.56×10-2°C/sec at an agitation speed of 300 rpm. Both series are analyzed by the stochastic model in which the first nucleation is treated as a random process.
    The waiting times distributed exponentially. The nucleation probability, a probability of first nucleation per unit time, calculated from the waiting times is correlated to the 1.30th power of agitation speed and to the 1.38th power of supercooling. The critical supercooling is related to cooling rate by the model and this equation is compared with the similar one of Nývlt. The critical supercooling calculated by the equation of the model agrees with the experimental values. The nucleation probability is suggested to be identical with a nucleation rate.
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  • KUNIO SHINOHARA, ATSUSHI YASUDA
    1978 Volume 11 Issue 4 Pages 296-301
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
    Pneumatic escalator is examined as to its heat transfer characteristics with particles. Change in particle temperature in the horizontal direction of overall particle flow is measured by a radiation thermometer. An experimental equation of particle temperature is made under various operating conditions such as air flow rate, particle feed rate and inlet air temperature. An apparent coefficient of heat transfer based on particle temperature alone is evaluated by heat balance and rate of heat transfer between particles and air or wall surfaces.
    As a result, it is found that Nusselt''s number increases with particle Reynolds number, particle concentration and average temperature of air within each sectionalized cell and with decreasing particle size. Thus, a pneumatic escalator could suitably be designed and utilized for continuous and simultaneous heating operations on the basis of the heat transfer data obtained.
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  • TAMOTSU HANZAWA, KAZUO SAKAUCHI, KUNIO KATO, TEIRIKI TADAKI
    1978 Volume 11 Issue 4 Pages 302-308
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
    Concentration distributions of reactant gas in a horizontal epitaxial reactor were numerically calculated from fundamental equations for the case where the overall reaction rate is affected by the surface-reaction rate at the reaction surface. The reactant concentration in the reactor was affected by distance from the leading edge, feed rate of gas, width of reaction zone and reaction rate constant, but the profile of reactant concentration distributions in the cross-sectional direction were not affected very much by these factors. However, the concentration distributions were influenced quite sensitively by Gr. To check the calculated results, carbon plates were burned in this reactor under the same conditions as those in the calculation, and local concentration of carbon dioxide was measured. The calculated concentration distributions agreed well with the experimental ones. Furthermore, the reactant concentration distributions for the case of surface reaction rate control were compared with those for the case of mass transfer rate control, and the concentration distributions of the former became more uniform than those of the latter.
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  • SHINTARO FURUSAKI, MICHIO TAKAHASHI, TERUKATSU MIYAUCHI
    1978 Volume 11 Issue 4 Pages 309-314
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
    Effect of the freeboard and the transition region on stability of fluid catalytic reactors is presented. Wall heat transfer coefficient and solid circulation rate have a significant effect on stability. These properties were measured. Both decrease as bed density decreases in the dilute phase (freeboard) and transition region. On the premise that non-catalytic violent reactions are induced due to temperature rise initiated by catalytic reactions in the dilute phase and/or the transition region, an approach to instability of the reaction system is presented by calculations. If the noncatalytic reactions are highly exothermic and their activation energies are large, the system can easily run away at any level of solid circulation. Thus, the possibility of these non-catalytic reactions, e. g. combustion or polymerization, should be avoided by such means as control of inlet compositions or close control of temperature in the dilute phase.
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  • MOMPEI SHIRATO, TOSHIRO MURASE, NIICHI HAYASHI, TETSUO NOGUCHI
    1978 Volume 11 Issue 4 Pages 315-318
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
    To improve deliquoring rates in batch-type expression equipment, expression experiments of thickend slurry and semi-solid materials were carried out at constant expression pressure by using a compression-permeability cell equipped with vertical, permeable strings. The experiments showed that filtration with strings can be represented by Ruth''s filtration equation and the successive consolidation processes by the consolidation equation based upon the Terzaghi-Voigt model. Consequently, the experimental values of filtration coefficient Ks and consolidation coefficient (Ce)s can be determined by using experimental data. The string effects on filtration and consolidation rates are evaluated in terms of the increase in K and Ce values. It has become apparent that the effects depend heavily on the ratio of radial to vertical maximum drainage distance iR/L0 and the increase in deliquoring rates is remarkable when iR/L0≤1.0.
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  • HIROSHI KUBOTA, YASUO HOSONO, KOICHI FUJIE
    1978 Volume 11 Issue 4 Pages 319-325
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
    An aeration system employing a long vertical shaft of 100 m or more depth has recently been developed by ICI. The interior of the shaft is divided into two parts. Air bubbles sparged in one side of the interior flow down to the bottom and then flow up through the other side of the shaft to the surface, as liquid circulates through both sides. This liquid circulation is maintained by the gas lift action of the sparged air. In this aeration system, the flow path of the air bubbles introduced is long enough to yield high oxygen utilization.
    In the present paper, the authors discuss operating problems of ICI''s deep shaft aerator. The airlift type deep shaft was simulated by a mathematical model. The momentum balance equation for the fluid flow, the theoretical and empirical relations between gas velocity, liquid velocity, gas slip velocity and gas holdup, and the mass balance equation for oxygen transferred through the gasliquid interface, were all simultaneously solved to obtain the distributions of gas holdup and oxygen utilization along the shaft length.
    The calculated results give valuable information, such as the relations between the gas velocity, liquid circulation velocity, depth of air introduced and oxygen utilization. The power economy of the deep shaft is discussed in connection with its design and operating problems.
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  • A. G. POLLIN, VOJTECH FRIED, MASAHIRO YORIZANE
    1978 Volume 11 Issue 4 Pages 326-327
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
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  • U. P. GANGULY, P. SEN GUPTA
    1978 Volume 11 Issue 4 Pages 328-331
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
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  • KORETSUNE UEYAMA, JUN''ICHI HATANAKA
    1978 Volume 11 Issue 4 Pages 331-334
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
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  • MOMPEI SHIRATO, TOSHIRO MURASE, KUNIO ATSUMI, TAKATOSHI NAGAMI, HIROMI ...
    1978 Volume 11 Issue 4 Pages 334-336
    Published: August 20, 1978
    Released: March 31, 2006
    JOURNALS FREE ACCESS
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