JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
Print ISSN : 0021-9592
Volume 21 , Issue 2
Showing 1-18 articles out of 18 articles from the selected issue
  • SATORU ASAI, YASUHIRO KONISHI, YUKIYASU SASAKI
    1988 Volume 21 Issue 2 Pages 107-112
    Published: April 20, 1988
    Released: April 19, 2006
    JOURNALS FREE ACCESS
    The mass transfer coefficients between solid particles and turbulent liquids were measured in agitated vessels. For large particles characterized by large values of the specific power group (γ1/3d4/3/v), the measured mass transfer coefficients were in good agreement with Levins and Glastonbury''s correlation. For fine particles less than 100μm, however, the mass transfer coefficient deviated below their correlation, reaching more rapidly the theoretical limiting value Sh = 2 for molecular diffusion in an infinite stagnant fluid. This lends the first quantitative support to the postulate that fine particles may stay in and move together with microeddies. A new correlation for the mass transfer coefficient is presented. The effect of particle density and vessel diameter on the mass transfer coefficients was found to be negligible. Furthermore, the effect of solid particle concentration was found to be of little importance in the range of specific surface area up to at least 3000m2/m3 of liquid.
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  • KAZUYUKI SHIMIZU, MAKOTO MORIKAWA, SATORU MIZUTANI, SHINJI IIJIMA, MAS ...
    1988 Volume 21 Issue 2 Pages 113-117
    Published: April 20, 1988
    Released: April 19, 2006
    JOURNALS FREE ACCESS
    A comparative evaluation of on-line control techniques was made for the glucose-controlled fed-batch culture of baker''s yeast. Based on the comparison of control qualities by computer simulation, two methods -moving identification combined with optimal control and programmed-PI control- were adopted for the experiments to keep the glucose concentration in the culture broth at low level. The control variable was the feed rate of concentrated glucose. The glucose concentration in the culture broth was measured on-line every 5 min using an automatic glucose analyzer. The glucose concentration in the broth was controlled in the range of 0.1-0.2 kg/m3 with these control strategies.
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  • OSAMU ARIGA, TOHRU WATARI, KIMIHISA TAKEUCHI, MASATAKA ANDO, HIROMI TA ...
    1988 Volume 21 Issue 2 Pages 117-122
    Published: April 20, 1988
    Released: April 19, 2006
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    Stability of a recombinant plasmid pMCT98 was investigated for free and immobilized Escherichia coli C600/pMCT98 cells. KC1, a hardening reagent for immobilizing matrix, inhibited cell growth and decreased the stability of the plasmid for free cells. However, the immobilization within ic-carrageenan gel did not affect cell growth and increased significantly the stability of the plasmid, and the amount of the gene product did not decrease through successive passage of the immobilized cells. Coexistence of plasmid pRLK13 lowered the stability of plasmid pMCT98 for both free and immobilized cells. Some oscillations in the ratio of cells harboring the plasmids were observed in the immobilized E. coli C600/pMCT98/pRLK13 system.
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  • FUMIYA YOSHIDA, MANABU YAMAGUCHI, TAKASHI KATAYAMA
    1988 Volume 21 Issue 2 Pages 123-129
    Published: April 20, 1988
    Released: April 19, 2006
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    An experimental study was carried out for the dispersion of water drops from a water film which flowed down an inclined plate with notched flash-boards into a continuous dielectric liquid phase in an electric field. Hydrodynamic characteristics of the dispersion were examined experimentally for three kinds of continuous phase. An empirical equation is proposed for the Sauter mean diameter of drops dispersed in the electric field. It is confirmed that the moving velocities of drops can be closely estimated by an empirical equation of Takamatsu et al. Dispersed-phase holdup is correlated with dimensionless electric stress, which is determined by physical properties of the liquids used and operating conditions. An empirical equation including the effect of the distance between two flash-boards, L, on the holdup is proposed in the range of 30 < L < 50 mm. The effect of distance is explained quantitatively by electric field strength on water film on the flash-board, calculated numerically by the boundary element method.
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  • TAKASHI NAKAYAMA, HIROSHI SAGARA, KUNIO ARAI, SHOZABURO SAITO
    1988 Volume 21 Issue 2 Pages 129-134
    Published: April 20, 1988
    Released: April 19, 2006
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    For the separation of fusel oil from low-concentration fermentation broths, ternary liquid-liquid equilibria at 323.2 K were measured for the systems of water and 1, 1-difluoroethane with alcohols (l-propanol, 1-butanol and 1-pentanol). The liquefied gas 1, 1-difluoroethane can achieve much higher distribution coefficients of l-propanol, 1-butanol and 1-pentanol than ethanol. Therefore, 1-propanol, 1-butanol and 1-pentanol will be selectively removed from low-concentration ethanol aqueous solutions with liquefied 1, 1-difluoroethane at low solvent ratios.
    The liquid-liquid equilibrium data were correlated by the UNIQUAC and NRTL equations. The UNIQUAC equation gave better correlation of the experimental data than did the NRTL equation. However, the two-phase regions estimated by the UNIQUAC equation were larger than the experimental results for the systems of water + 1-propanol + 1, 1-difluoroethane and water + 1-pentanol + 1, 1-difluoroethane.
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  • HIROMOTO USUI, MATSURU KODAMA, YUJI SANO
    1988 Volume 21 Issue 2 Pages 134-140
    Published: April 20, 1988
    Released: April 19, 2006
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    Aqueous solutions of polyethylene oxide were injected into a pipe flow through a small tube at the center of a pipe. The turbulent characteristics in drag-reducing flow with polymer injection were measured by means of a Laser Doppler Velocimeter (LDV). The experimental results were compared with measurements both in a Newtonian fluid (water) flow and in a premixed flow with 300 ppm homogeneous polymer solution.
    The experimental results suggested that the polymer injection caused a thickening of the buffer layer, enlargement of macroscale turbulent eddy and suppression of fine turbulent eddy. A difference in turbulent characteristics between premixed and polymer injected systems was observed in the distributions of turbulent macroscale, skewness factor and flatness factor. The enlargement of macroscale was more significant in the turbulent core region in the case of polymer injection experiments. The measurements of skewness and flatness factors showed that the low-speed fluid element caused by the ejection process passed more clearly the measuring position near the outer boundary of the buffer layer in the case of polymer injection experiments.
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  • TAKAO OHMORI, MINORU MIYAHARA, MORIO OKAZAKI, RYOZO TOEI
    1988 Volume 21 Issue 2 Pages 141-147
    Published: April 20, 1988
    Released: April 19, 2006
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    The heat transfer coefficient between a granular bed with aeration and a moving heating tube submerged in the bed was measured by use of a heat flux generator developed specifically for rapid measurement. The velocity of air flow was limited to less than the minimum fluidization velocity. A heat transfer model taking account of the effect of air flow was proposed. It was confirmed that this model can describe the effects on the heat transfer coefficient of various operation parameters including the velocity of air flow, the thermal properties of granular material, particle diameter and shape, and the diameter of the heating tube.
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  • XI-YIN ZHENG, GUANG-WEN WU, NAI-WEN ZHANG
    1988 Volume 21 Issue 2 Pages 147-157
    Published: April 20, 1988
    Released: April 19, 2006
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    A simple DDLC-EOS (density-dependent local-composition model combined with equations of state) unified model based on a conformal mixture as the reference state is proposed.
    Its applicability has been tested on more than 100 binary high-pressure vapor-liquid equilibrium data for several types of mixtures. For systems containing strongly polar and nonpolar substances or for some asymmetric mixtures, its fitting accuracies have been remarkably improved over those using the conventional Soave-Redlich-Kwong, Peng-Robinson and Patel-Teja equations of state. The proposed model is also capable of correlating vapor-liquid equilibria of nonpolar mixtures with the same or a slightly better accuracy than those cubic equations of state with the quadratic mixing rule.
    In addition, model energy parameters obtained from the data reduction of constituent binaries were then applied to predict vapor-liquid equilibria of several ternary systems. Predicted results were also better than those by conventional methods.
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  • NORIO OUCHIYAMA, TATSUO TANAKA
    1988 Volume 21 Issue 2 Pages 157-163
    Published: April 20, 1988
    Released: April 19, 2006
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    The authors'' theory of porosity estimation from particle size distribution was modified to make allowances for the size and species dependences of packing characteristics of particles. The new version is examined together with other existing theories by using well known relations and past experimental data. It is shown that the estimates by the modified theory are almost consistently in good agreement with the known data whereas the other theories examined show theoretical deficiencies that sometimes give rise to large deviations for mixtures of particles of remarkably different sizes. Some possible problems are also discussed in association with the new assumption introduced.
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  • MASAHIRO NIWA, HARUHIKO OHYA, EMIKO KUWAHARA, YOUICHI NEGISHI
    1988 Volume 21 Issue 2 Pages 164-171
    Published: April 20, 1988
    Released: April 19, 2006
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    Reverse osmotic concentration of aqueous MEK, THF and EAc solutions was carried out using five composite membranes (PEC-1000, FT-30 BW, FT-30 SW, NS-100 P1700, NS-100 P3500) and cellulose acetate membrane.
    Separation of solute and permeation through the membranes were measured under the following conditions: concentration of MEK, 1-8.2 wt%; concentration of THF, 0.7-6.3 wt%; concentration of EAc, 0.8-3.9 wt%; operating pressure, 4-6 MPa. PEC-1000 gave the best solute separation for each system. Its separation was above 97.5% for MEK system, above 99% for THF system and above 97% for EAc system.
    Membrane constants were calculated by the Spiegler-Kedem membrane transport model. The deviation from their model was corrected by compaction coefficients.
    Energy and membrane area required to concentrate aqueous MEK, THF and EAc solutions using PEC-1000 were calculated.
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  • JEONG H. CHOI, JAE E. SON, SANG D. KIM
    1988 Volume 21 Issue 2 Pages 171-178
    Published: April 20, 1988
    Released: April 19, 2006
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    A theoretical model for mean bubble size and frequency based on the collision theory with random spatial bubble distribution in freely bubbling gas-flu id i/ed beds was developed. A hemispherical bubble velocity diagram was constructed to determine the average bubble collision frequency. The resulting theoretical equation for predicting bubble size is
    (U-Umf)(Db-Db0)+0.474g1/2(D3/2b-D3/2b0)=1.132(U-Umf)h
    Bubble characteristics such as pierced bubble length, velocity and point frequency were measured in a square (30 × 30-cm) fluidized bed by means of an electroresistivity probe.
    The gradient of bubble size increased linearly with bubble voidage. The bubble Froude number also increased along the bed height with bubble voidage. The bubble Froude number represents approximately a linear relationship with the average fractional change of square root of the static energy of bubble rise along the bed height. The present model of bubble size was found to represent well the data in the literature.
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  • MANABU YAMAGUGHI, HIROYUKI SUGAYA, TAKASHI KATAYAMA
    1988 Volume 21 Issue 2 Pages 179-183
    Published: April 20, 1988
    Released: April 19, 2006
    JOURNALS FREE ACCESS
    A new spray column with vertical four-pole electrodes is developed for use as an electrostatic liquid extractor. The population behavior of dispersed drops in a d.c. electric field is studied in terms of dispersed-phase holdup, drop velocity, drop size distribution by use of the system of water drops in cyclohexane. It is found that the holdup characteristic, drop velocity and drop volume can be easily controlled by changing the strength of electric field in the two-phase flow contactor.
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  • TAKAO TSUKADA, NOBUYUKI IMAISHI, MITSUNORI HOZAWA
    1988 Volume 21 Issue 2 Pages 184-191
    Published: April 20, 1988
    Released: April 19, 2006
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    For the CZ crystal growth of silicon and sapphire, the flow and temperature fields with non-flat melt/crystal and melt/gas interfaces were studied theoretically by use of the finite element method.
    The theoretical method used here can predict the temperature distribution and the flow pattern (forced convection, free convection, Marangoni convection and their combined flow) in the melt and crystal, including the shapes of the melt/crystal and melt/gas interfaces and the crystal radius, although calculation was limited to the case of small CZ apparatus.
    It is found that the melt/gas interface shape affects the flow pattern in the melt, and that the melt/crystal interface shape for a system of small Pr such as silicon is not sensitive to the flow field. But for a system of larger Pr such as sapphire, the melt/crystal interface shape is strongly dependent on the flow field.
    It is also found that the Marangoni effect, if it operates, plays the most important roll in promoting the flow in the melt.
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  • TSUNEYUKI SATO, ITSUO TOYODA, YOSHIYUKI YAMAMORI, TOSHIKUNI YONEMOTO, ...
    1988 Volume 21 Issue 2 Pages 192-198
    Published: April 20, 1988
    Released: April 19, 2006
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    Chemical reactions of CO gas with copper(I)-tetrachloroaluminate(III)-aromatic hydrocarbon solutions, namely COSORB solutions, were investigated from the viewpoint of equilibrium and kinetics.
    The equilibrium and the non-equilibrium amounts of CO dissolved into COSORB solutions were measured by using a batchwise gas-liquid contactor.
    Equilibrium properties such as CO gas solubility constants or CO-complex stability constants for various solvent solutions were determined from the experimental data with the aid of the optimization technique. The solubility of CO decreased with temperature as well as with concentration of CuAlCl4. The stability constants were influenced by the π-electron releasing ability of the aromatic hydrocarbon molecule.
    A rational reaction mechanism is proposed to explain the non-equilibrium rate data obtained experimentally. The reaction followed a unimolecular substitution mechanism and was determined to be exothermic. The COcomplex stability constant calculated from the optimum rate constant was in good agreement with the results of the equilibrium experiments.
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  • MASAO SUDOH, TAKAMASA KODERA, HARUYOSHI HINO, HIROSHI SHIMAMURA
    1988 Volume 21 Issue 2 Pages 198-203
    Published: April 20, 1988
    Released: April 19, 2006
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    Both anodic oxidation and generation of hydrogen peroxide through electroreduction of oxygen may be useful for oxidative degradation of organic compounds. To clarify the effect of electrode reactions of both sides of a bipolar plate on the current efficiency for oxidative degradation of phenol, experiments were conducted by using an undivided bipolar electrolyzer having a vertical stack of perforated graphite electrodes. The Faradaic current If was arranged as a function of the electrode potential difference EB between opposite sides of a bipolar plate. By analyzing the If - EB curves for the electrolyses in solutions containing different reactants, separate currents corresponding to anodic and cathodic reactions were determined. The effect of EB on the COD current efficiency Ce(COD) for the oxidative degradation of phenol could be well explained by the contribution of the currents of phenol oxidation and oxygen reduction to the total current. The value of Ce(COD) in case of sparging oxygen showed a bimodal curve having the maximum values with respect to EB.
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  • TOSHIRO MURASE, MASASHI IWATA, ICHIO KATO, WON-DEOK LEE, MOMPEI SHIRAT ...
    1988 Volume 21 Issue 2 Pages 204-206
    Published: April 20, 1988
    Released: April 19, 2006
    JOURNALS FREE ACCESS
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  • KIYOTAKA SAKAI, SHINGO TAKESAWA, RISHICHI MIMURA, HIDEHIKO OHASHI
    1988 Volume 21 Issue 2 Pages 207-210
    Published: April 20, 1988
    Released: April 19, 2006
    JOURNALS FREE ACCESS
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  • HIDEO NISHIUMI
    1988 Volume 21 Issue 2 Pages 210-214
    Published: April 20, 1988
    Released: April 19, 2006
    JOURNALS FREE ACCESS
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