KAGAKU KOGAKU RONBUNSHU
Online ISSN : 1349-9203
Print ISSN : 0386-216X
ISSN-L : 0386-216X
Volume 10 , Issue 1
Showing 1-19 articles out of 19 articles from the selected issue
  • Hitoshi Kosuge, Koichi Asano
    1984 Volume 10 Issue 1 Pages 1-6
    Published: January 10, 1984
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Experimental studies of vapor-phase diffusion fluxes of each component and sensible heat fluxes in ternary distillation of acetone-methanol-ethanol system were made by a wetted-wall column at total reflux conditions.
    Observed vapor-phase diffusion fluxes of each component were found to be affected by vapor velocity and by length of wetted-wall column. The data were well correlated in terms of modified Graetz number with effective diffusion coefficient.
    Effect of vapor condensation of vapor-phase diffusion fluxes and sensible heat fluxes showed good agreement with results of numerical solution by a previous worker. Dimensionless vapor-phase diffusion fluxes and sensible heat fluxes with correction of the effect of vapor condensation showed good agreement with the theoretical values by Graetz model.
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  • Mitsuo Takahashi, Shinji Takahashi, Hiroji Iwasaki
    1984 Volume 10 Issue 1 Pages 7-9
    Published: January 10, 1984
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Viscosity of gaseous R-12 was measured using a oscillating disk viscometer of Maxwell type at 298.15398.15 K in the pressure range up to 4.1 MPa. An empirical equation was obtained to represent the viscosity at normal pressure as a function of temperature. Force constants for Lennard-Jones 12-6 potential were determined from the observed viscosity values at normal pressure as follows : ε/k=215.9 K, σ = 0.5496nm.
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  • Yasuhiko Nozaki, Shintaro Furusaki, Terukatsu Miyauchi
    1984 Volume 10 Issue 1 Pages 10-16
    Published: January 10, 1984
    Released: November 12, 2009
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    Conversion data for a fluidized catalyst bed of 0.1 m in diameter and 2 m in height, obtained by use of absorption of CO2 gas in air into alkaline solution supported on fluidized particles, were studied. Experimental results obtained at a superficial velocity of 0.1 to 0.6 m/s of air were analyzed with the successive contact model by use of the Lewis-Gilliland-Glass plot. Bubble measurements using a hot-wire probe were also carried out and the results were studied together with the absorption rate data. The following results were obtained : (1) The overall volumetric mass transfer coefficient between the bubble phase and the emulsion phase varied from 0.29 to 0.74 s-1 with UG; this was explained by the difference in mean bubble hold-up. (2) The ratio of direct-contact particles to the total volume of particles in the bed was expressed as 0.18 × UG1.2, which corresponded fairly well to the fraction of particles in the dilute phase. (3) Mean bubble diameter along the axis of the bed from measurements by the hot wire method was (3.2, 2.2, 1.4) × 10-2 m for alkaline supported alumina particles, FCC and alumina particles, respectively. The rising velocity of the bubbles was about 0.9 m/s for all particles.
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  • Shigeru Sano, Fumio Saito, Saburo Yashima
    1984 Volume 10 Issue 1 Pages 17-24
    Published: January 10, 1984
    Released: November 12, 2009
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    The adhesive forces of 4 kinds of glass powders and 3 kinds of mineral powders on the surface of glass plate were measured by a centrifugal method and the influence of atmospheric humidity and the shape of the powders on the adhesive forces was experimentally studied.
    The results are summarized as follows :
    1) Concerning the effect of atmospheric humidity, the adhesive forces of the powders increased slowly with increasing humidity in the range of relative humidity of 10% to 80%.
    On the other hand, the adhesive forces increased suddenly with increasing humidity when relative humidity exceeded 80%. In the range of relative humidity under 10%, they tended to decrease. Thus the overall relationships between the adhesive forces and relative humidity can be shown as reverse S type curves. 2) With regard to the effect of the shape of glass powders, the adhesive forces of powders decreased with decreasing shape factor. Spherical particles showed the maximum adhesive forces, and with increasing irregularity of shape the adhesive forces gradually decreased.
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  • Yuji Yoshimura, Minoru Kurita, Toshio Sato, Hiromichi Shimada, Akio Ni ...
    1984 Volume 10 Issue 1 Pages 25-32
    Published: January 10, 1984
    Released: November 12, 2009
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    A coal liquid obtained from the coal liquefaction processes of the Sumitomo Coal Mining Co. applied to sub-bituminous Wandoan Coal was hydroprocessed in a continuous stirred tank reactor with stationary catalyst basket.
    The activities of Co-Mo and Ni-Mo-γ-alumina catalysts decreased in the order of hydrodesulfurization activity > hydrocracking activity of hexane insolubles to oil fractions > hydrodenitrogenation, and the deactivation rates of these catalysts decreased in the order of hydrodenitrogenation activity > hydrodesulfurization activity > hydrocracking activity of hexane insolubles to oil fractions.
    The Ni-Mo-γ-alumina catalyst was superior in hydrodenitrogenation activity to the Co-Mo-γ-alumina Catalyst.
    From the relations observed between these hydrotreating activities and average pore sizes of catalysts and between carbon deposits and average pore sizes, it was found that the hydrogenating and hydrocracking reactions were strongly influenced by pore diffusion. By measuring the changes in pore size distributions of spent catalysts and radial concentration profiles of carbon deposits on the spent catalysts, it was found that the deactivation of catalysts might be mainly the results of carbonaceous material deposits on the catalysts in these experiments.
    Metal deposits on the catalyst surfaces were another reason for catalyst deactivation. Of these metals, titanium, alkaline metals and alkali earth metals selectively deposited on the catalyst surfaces from the coal liquid, and iron was found in narrow bands on the surfaces of spent catalysts.
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  • Yasuo Hirose, Mitsutoshi Tsuda
    1984 Volume 10 Issue 1 Pages 33-37
    Published: January 10, 1984
    Released: November 12, 2009
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    A variety of chemical engineering problems is finally confronted with a non-linear simultaneous equation. The Newton-Raphson method reduces the non-linear problem into a linear one. From the computational point of view, it is important to solve this linear equation with as small memory as possible. Here is presented a new algorithm to solve a block-tridiagonal linear equation containing a singular submatrix whose inverse cannot be obtained. The first case : when the temperature of a specified plate is given, the residual function of that plate must be replaced with another one. This replacement makes a singular Jacobian submatrix containing a zero-row. The second case : when the feed enthalpy is unknown, a variable, the vapor flow rate at the top of the tower, must bt replaced with the feed enthalpy. This replacement makes a singular Jacobian submatrix containing a zero-column. Numerical examples of the two cases above show the effectiveness of the present method.
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  • Hisashi Miyashita, Akio Nakamura, Seiichi Hirano, Kaichiro Wakabayashi
    1984 Volume 10 Issue 1 Pages 38-42
    Published: January 10, 1984
    Released: November 12, 2009
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    An experimental study of the mechanism of mass transfer on the inner tube wall in an eccentric annulus was carried out by use of an electrochemical method.
    The circumferential distribution of local mass transfer coefficient on the inner tube was measured by varying the Reynolds number, the radius ratio value (D0/Di) and the eccentricity values. To examine the transfer mechanism, wall shear stress on the inner tube wall and its fluctuation intensity were measured.
    From the behavior of the distributions of the factors mentioned above, it was found that the tendency of distribution of local mass transfer coefficients depended on the shear stresses. In addition, it was found that the turbulence level of the shear stress fluctuation was highest at ±60 degrees from the narrowest cross section in the eccentric annulus. Also, as the flow rate began to fall against the narrowest section from the turbulence section, then the mass transfer coefficients became small.
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  • Masao Sudoh, Naohiro Nomura, Kozo Koide
    1984 Volume 10 Issue 1 Pages 43-48
    Published: January 10, 1984
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Oxidative degradation of aqueous phenol effluent was achieved by using an electrochemical reactor with β-PbO2 anode or graphite anode (partly used) and stainless steel plate (SUS316) cathode without diaphragm.
    Effects of anode potential and phenol concentration on current efficiency were experimentally examined. β-PbO2 had a higher current efficiency and lower consumption of electrode than graphite. With β-PbO2 anode, the current efficiency of phenol oxidation was more than 30%, reaching a limiting value of about 50% under conditions of over 5.0 mol·m-3 phenol concentration and anode potential below 1.5 V.
    By the analysis of oxidation products, it was shown that phenol was electrochemically oxidized to hydroquinone and p-quinone successively and decomposed to maleic acid, and that COD was conclusively reduced.
    Electrochemical degradation is effective as a pretreatment for the decrease of high concentration of phenol to a concentration of about 5.0 mol·m-3.
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  • Masafumi Mochizuki, Kazuo Sato
    1984 Volume 10 Issue 1 Pages 49-55
    Published: January 10, 1984
    Released: November 12, 2009
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    The Sauter-mean drop diameter d32 near the impeller tip was directly measured by photographs. Turbine impellers with various geometries were used. The following results were obtained. 1) Mean drop diameter within the impeller region was proportional to the-3/4 power of Weber number. 2) At constant Weber number, mean drop diameter was reduced to a minimum at B/D=0.3 (B= width of impeller blade, D=impeller diameter) and number of impeller blades nb=6. 3) The concept of helical flow intensity was presented and developed extensively. It was shown that normalized mean drop diameter D32 is a unique function of the helical flow intensity. 4) The interfacial area per unit power input was minimum at B/D=1/8 and nb=2.
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  • Naonori Nishida
    1984 Volume 10 Issue 1 Pages 56-61
    Published: January 10, 1984
    Released: November 12, 2009
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    An interactive algorithm for the solution of parameter estimation problems is presented. An interactive algorithm for multiple criteria problems developed by previous investigators is successfully applied to the solution of parameter estimation problems. The algorithm proposed here is suited to the solution of such parameter estimation problems as the following : (1) The errors in observed values are not subjected to the specific distribution function. (2) The number of observed values is scarce. For these types of parameter estimation problem, the usual parameter estimation methods such as the least square method are difficult to apply.
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  • Ikuho Yamada, Hideki Mori, Satoshi Matsui, Setsuro Hiraoka, Shigekatsu ...
    1984 Volume 10 Issue 1 Pages 62-67
    Published: January 10, 1984
    Released: November 12, 2009
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    A method is proposed for determining the minimum temperature of heat source required for the separation of a binary mixture by use of three types of multi-effect distillation : forward feed, individual feed and backward feed types.
    The feature of the proposed method is to solve a set of nonlinear simultaneous equations composed of enthalpy balance of the multi-effect distillation processes by using a quasi-linearization method. The stable convergence of the proposed method is demonstrated in numerical examples of binary separation of 2-methylpentane-n-hexane system.
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  • Tsutao Otake, Setsuji Tone, Isao Komasawa, Masao Kawashima
    1984 Volume 10 Issue 1 Pages 68-74
    Published: January 10, 1984
    Released: November 12, 2009
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    The kinetics and mechanism of chloride volatilization of such heavy metal oxides as PbO, ZnO, CuO and CdO contained in sludge were studied at atmospheric pressure and at 7731023 K, employing HCl gas or a mixture of CaCl2 and SiO2 as chlorinating reagents.
    Where HCl gas was used, the overall reaction rate was controlled by the diffusion rate of HCl gas through the gas film at high temperature and by the vaporization rate of the resultant metal chlorides at low temperature. Where CaCl2 and SiO2 were used, the decomposition of CaCl2 and formation of HCl is much enhanced by SiO2. The metal oxides are promptly chlorinated by HCl, and the overall rate is controlled by the vaporization of the resultant metal chlorides.
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  • Katsuhiko Fujinawa, Tamami Komatsu, Mitsunori Hozawa, Nobuyuki Imaishi ...
    1984 Volume 10 Issue 1 Pages 75-81
    Published: January 10, 1984
    Released: November 12, 2009
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    The extraction of copper by a W/O/W type liquid surfactant membrane process was studied experimentally using a stirred cell. The effect of the mean drop diameter dp of the inner water phase of the W/O emulsion on the extraction rate N0 and on the breakage ratio ε of the membrane were investigated. Kerosine, Span 80, an aqueous solution of cupric sulfate solution, and an aqueous solution of sulfuric acid and ammonium sulfate, which is the tracer of the breakage, were used as the oil phase, the surfactant, the outer water phase and the inner water phase, respectively. As the extraction reagent, LIX65N and LIX64N were used. The extraction rate N0 was measured using an ion electrode.
    The following points were determined experimentally; N0 increases with pH of the outer water phase. N0 is proportional to dp-1 in the case of LIX65N, while No is proportional to dp-0.3 in the case of LIX64N when pH is 5.72. The breakage ratio ε essentially increases as dp increases. For stabilization of the membrane, there is a critical value ncr of the number of the adsorbed layer, n, of the surfactant at the interface. If n>ncr, ε is independent of the concentration Cs of the surfactant. But if n<ncr, ε increases rapidly as Cs decreases.
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  • Tadaatsu Ido, Toshimi Kohmura, Shigeo Goto
    1984 Volume 10 Issue 1 Pages 82-88
    Published: January 10, 1984
    Released: November 12, 2009
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    The reaction paths and kinetics of methanol to methane on a nickel catalyst were studied in a flow tubular reactor at 200-400°C and atmospheric pressure. When the time factor was small, carbon monoxide and hydrogen formed at the proportion of 1 to 2, respectively, by decomposing methanol. As the time factor increased, methane was produced by the hydrogenation of carbon monoxide and then carbon dioxide by the water-gas shift reaction. The kinetics of hydrogenation of carbon monoxide and carbon dioxide and of water-gas shift reaction were investigated on the same catalyst at 250°C. In the case of hydrogenation of carbon monoxide, methane and water were mainly produced and carbon dioxide was formed as a by-product. In the water-gas shift reaction, carbon dioxide and hydrogen were formed but the formation of carbon dioxide decreased with increasing amount of hydrogen.
    In the hydrogenation of carbon dioxide, only methanation took place, but this reaction was inhibited by the presence of carbon monoxide. Experimental data of methanol-to-methane formation were in good agreement with the results calculated by using the kinetics of the respective reactions.
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  • Toshiro Murase, Niichi Hayashi, Masashi Iwata, Kazuhito Itoh, Mompei S ...
    1984 Volume 10 Issue 1 Pages 89-95
    Published: January 10, 1984
    Released: November 12, 2009
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    For the high-degree expression of solid-liquid mixture, a method of building up high expression pressure is studied under a repeated load by using a compression-permeability cell with specially designed piston. The compression surface of the piston is partly cut off, and a repeated load is periodically applied to the piston, which rotates intermittently. The semisolid material of water-works sludge is consolidated under high oscillating pressure, which is produced by the reduction of contact area between the loading piston and the mixture. The contact-area decrease effects on high-degree separation are evaluated in comparison with the expression performance under constant pressure. Remarkable increases in expression rate and dehydrated liquid volume are confirmed under the conditions where the initial solid concentration of the semisolids ranges from 0.56 to 0.65. It is shown that the drastic improvement of expression performance depends heavily on both the concentrated and repeated load while the performance is not affected by the load oscillation only.
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  • Tatsuo Tokimasa, Yoichi Nagase, Masaaki Hara
    1984 Volume 10 Issue 1 Pages 96-101
    Published: January 10, 1984
    Released: November 12, 2009
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    Following work by the authors reported previously, Reynolds stress measurement has been carried out for the initial stage of mixing-layer flow characterized by a growing-up period of two-dimensional vortical motion before its pairing.
    It was found that the sum of the stresses over the mixing-layer width showed a periodic variation with downstream distance. The sum increased abruptly at the beginning of the roll-up and then decreased because of mutual interaction between vortices. This periodicity should be conjugated with that in the vortex-pairing period, which was pointed out by Hussain et al.
    Reynolds stress, -ρu'v', distribution in a vortex was as follows : (1) with respect to a young vortex, there was a large but minus region with entrainment from the high-velocity side and a large plus region with entrainment from the low-velocity side; (2) with respect to a rather old vortex caused by the mutual interaction of vortices, which was characterized by a double-roll structure of high-and low-velocity fluid, two of the large plus regions laid around the boundary between the high and low velocities with a 180-degree phase lag and a pair of small minus regions were also found on a 90-degree phase lag relative to the plus region. Thus the plus and minus regions of the Reynolds stress transform from a round vortex to an elongated one.
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  • Kohei Ninomiya, Hiroshi Fujii, Hisashi Kono
    1984 Volume 10 Issue 1 Pages 102-107
    Published: January 10, 1984
    Released: November 12, 2009
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    Absorption of NOx gas into aqueous ammonium carbonate solutions was studied, using a packed column with cocurrent downward flow. The relation between the flow pattern and the selectivity of NO3- was investigated. In the trickle-flow region where kL, is small, the selectivity of NO3- is increased due to the presence of an acid portion in the liquid film, if the diffusion rate of alkaline component is not faster than the absorption rate of NOx gas. In the bubble-flow region where kL is large, the selectivity of NO3- is increased in spite of the absence of an acid portion in the liquid film.
    In this case, the results could be satisfactorily interpreted on the basis of a theory of simultaneous absorption with first-order reactions of N2O3 and N2O4. The absorption rate of N2O4 was expressed by the physical absorption rate for large kL.
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  • Yoshiteru Kanda, Shigeru Sano, Fumio Saito, Saburo Yashima
    1984 Volume 10 Issue 1 Pages 108-112
    Published: January 10, 1984
    Released: November 12, 2009
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    An experimental study of single-particle crushing at slow compression rate was carried out for two kinds of glassy and five kinds of natural materials. The specimens were almost spherical particles of 0.5 to 3.0 cm in diameter.
    The relationships between particle size and fracture energy (strain energy) were calculated by using the results of the size effect ranging from about 10 cm to 0.0030 cm of single particle crushing, as shown in the previous papers. The experimental results are summarized as follows :
    1) The fracture energies obtained were larger than the values calculated from the theoretical equations for limestone, marble and gypsum.
    2) For natural materials, the specific fracture energies rapidly increased with decreasing particle size within the range of particle size smaller than about 500 μm.
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  • Hitoshi Takase, Hajime Unno, Takashi Akehata, Toshifumi Ishikura, Hisa ...
    1984 Volume 10 Issue 1 Pages 113-132
    Published: January 10, 1984
    Released: November 12, 2009
    JOURNALS FREE ACCESS
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