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Atsuo Murata, Shigeo Oba, Takeshi Ishikawa, Mitsuho Hirata
1982 Volume 8 Issue 6 Pages
655-658
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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For the design of a distillation column to separate high-purity geraniol from a mixture of geraniol, nerol and citronellol, vapor pressure of pure components and vapor-liquid equilibria of binary mixtures were measured. Further, to prove separation performance, distillation experiments were carried out at 20 mmHg by using a 70 mmφ Sulzer packed column.
Experimental results show that the high-purity geraniol separation can be achieved successfully by low-pressure distillation.
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Hideo Suematsu, Shiro Inoue
1982 Volume 8 Issue 6 Pages
659-663
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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As a basic study in predicting the heat transfer characteristics of fluted tubes, the flow characteristics of falling liquid films on vertical fluted walls have been studied experimentally. Four kinds of fluted tubes were used in the experiments.
The following conclusions were obtained.
1) By considering the hydraulic radius, the flow characteristics can be summarized to several experimental correlations which are similar to the Nusselt solution for a vertical flat wall and are almost independent of the configurations of the flutes.
2) On estimating the volumetric flow rate of falling liquid film in a flute, numerical analysis of falling liquid film without wavy laminar flow can be used up to a Reynolds number of about 1000.
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Yosuke Kawashima, Masayoshi Nakagawa, Satoru Iuchi
1982 Volume 8 Issue 6 Pages
664-670
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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Flow patterns due to confluence in a two-dimensional, right-angled, T-shaped flow section were solved numerically by using a
k-ε turbulence model. The calculated results were compared with experimental results in respect of macroscopic characteristics of confluent flow, and the applicability of the
k-ε model to confluent flow was investigated. Calculations were carried out for cross-sectional area rations of 1.0 and 2.0 and for flow rate ratios of 0.1, 0.3, 0.5, 0.7, and 0.9. Reynolds number downstream, with
W1 as a characteristic length, was 25000 (
W1 : width of main pipe).
It was shown that the calculated results agreed well with the experimental results.
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Masashi Kuramae
1982 Volume 8 Issue 6 Pages
671-676
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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This paper deals with a method for predicting the drying characteristics of a coarse granular bed.
The method is based on the known relationship between capillary suction pressure and moisture content, and the static balance between capillary and gravity forces where the inertial effects are neglected for the estimation of moisture content distribution during the constant-rate drying period. It is proved that the present method is generally preferable for the granular bed of particle diameter larger than 200 μ.
Furthermore, the method is extended to estimation of the characteristic drying curve, the time required for complete drying and the critical moisture content in conductive drying, and the validity of these extensions is studied.
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Katsuyuki Kubota, Shinya Hayashi, Masaharu Nishijima, Junji Uzuki
1982 Volume 8 Issue 6 Pages
677-684
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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The underlying mechanism for the separation achieved in a nonfoaming adsorptive bubble separation column was studied both experimentally and theoretically by means of a strong and familiar anionic surfactant, sodium dodecylbenzenesulfonate, DBSNa, M.W. = 348.48, and a modified semiempirical mathematical model.
The adsorption rate of dodecylbenzenesulfonic group, DBS-, to the gas-liquid interface was relatively large and could be formulated in terms of the Langmuir adsorption equation.
The concentration profiles of the continuous and the dispersed phases, established in a slender vertical bubble column operating in a concurrent-flow system, were predicted by the present semiempirical model, composed of simultaneous first-order ordinary differential equations, and it was found that the present model is simpler and more convenient for predicting the profiles than is the previous lumped parameter model, in which the liquid-side mass transfer coefficient remains constant irrespective of the retention time of a bubble in the column. The present model enables us to predict the removabilities of the present surfactant.
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Fujio Watanabe, Masanobu Hasatani
1982 Volume 8 Issue 6 Pages
685-692
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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Using active carbon particles of 3 to 10 mm diameter, experiments in adsorption of phenol and benzoic acid from aqueous solution were carried out, and the adsorption rate and intraparticle distribution of local adsorption equilibrium were measured for two cases : a circulation batch method (Case 1) in which the extraparticle concentration is kept constant, and an ordinary batch adsorption method (Case 2). The data obtained were compared with the respective numerical solutions of three sorts of diffusion equations in which different rate-controlling steps were assumed, and the intraparticle diffusion kinetics accompanied by adsorption were studied.
1) The calculated shape of intraparticle distribution of local adsorption equilibrium differs among the rate-controlling steps assumed, but these differences become clearer for the Case 1 than for the Case 2 experiment. Thus the diffusion kinetics can be identified more easily from the Case 1 experiment.
2) The experimental data for the phenol adsorption shows best agreement with results calculated from the equation assuming simultaneous pore and surface diffusion. The benzoic acid adsorption is related most closely to the surface diffusion control.
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Akira Kurata, Seiji Sanga
1982 Volume 8 Issue 6 Pages
693-698
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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The secondary effluent of municipal wastewater was treated with a reverse osmosis pilot plant. The regenerated water was applied to feed water of a low-pressure boiler and its feasibility and economics for reuse were investigated.
Pilot plant tests were conducted for about 14 000 hours, using a tubular module and two kinds of spiral-wound modules. The effect of operating conditions on water flux and water quality through the reverse osmosis membranes and the deposition of scale and/or corrosion in the boiler, etc. were studied.
It was found that the quality of water obtained by the reverse osmosis process was suitable for boiler feed water and the operating cost of a spiral-wound module would be competitive with the use of tap water.
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Hiroyuki Tanaka, Hiroshi Komiyama, Hakuai Inoue
1982 Volume 8 Issue 6 Pages
699-703
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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The catalytic oxidation reaction of dissolved ammonia with Co
2O
3 was studied at 463 to 523K and 3 to 6 MPa. The reaction proceeds according to the stoichiometric relation 4NH
3+3O
2→2N
2+6H
2O. Kinetic studies showed that the reaction follows the first-order law with respect to both oxygen and ammonia and exhibits an activation energy of 61 kJ · mol
-1. This catalytic reaction might be effectively incorporated as a denitrogenation step in the waste-water treatment process with wet air oxidation.
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Masaharu Takao, Hitoshi Horikiri, Kai Wang, Yasuhiro Murakami
1982 Volume 8 Issue 6 Pages
704-709
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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The relation of the degree of deviation defined by a first-order centered moment of concentration and the degree of standard deviation defined by a square root of variance of concentration of fluid, to the unreacted fraction for instantaneous reaction under unity of stoichiometric ratio was investigated both by experiments of physical mixing and chemical reaction performed at lower Reynolds numbers in a baffled stirred thank with turbine impeller, and by a theoretical study with use of a simplified mass exchange-type model. In the physical mixing experiment, a number of local concentrations were measured in the course of mixing between potassium chloride solution and distilled water stratified in two phases due to a slight difference in density, and the degree of deviaion and the degree of standard deviation were calculated. In the chemical reaction experiment, a number of concentrations of product were measured in the course of instantaneous reaction between acetic acid solution and ammonium hydroxide solution stratified in two phases due to a slight difference in density, and a mean unreacted fraction was calculated. It is found from these experiments that the degree of deviation is almost the same as the degree of standard deviation and, at the same time, agrees with the mean unreacted fraction within 3% experimental error. This experimental result is shown to be almost fully explained by the simplified mass exchange-type model.
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Saburo Yashima, Fumio Saito, Yoichi Masuko
1982 Volume 8 Issue 6 Pages
710-716
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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Impact crushing experiments with single irregularshaped particles made of five kinds of minerals having a size range of 0.95-3.9 cm was carried out by use of a double-pendulum impact testing apparatus.
The experimental results are summarized as follows : 1) The experimental relationship between specific fracture energy and impact energy was similar to the theoretical one derived from the theory of impact between two elastic bodies under the condition that the particle is not fractured. But specific fracture energies were less than the values calculated from the theoretical equation. 2) The experimental relationship between impulse and specific fracture energy was in good agreement with the theoretical one. 3) By the use of volume equivalent particle diameter as a characteristic particle size of irregular particles, the experimental relationships 1) and 2) mentioned above were both in fair agreement with those obtained by using spherical particles. 4) Size distributions of fractured products were represented by the GM-H size distribution equation. And new surface produced was increased with increasing impact energy. 5) The energy law was similar to the final fineness limit theory proposed by T.Tanaka. 6) Crushing efficiency of a irregular-shaped particle was better than that of a spherical particle in the range of large impact energy.
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Hiroaki Masuda, Tsukasa Motooka
1982 Volume 8 Issue 6 Pages
717-721
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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The classification performance of a newly constructed two-stage virtual impactor was studied both theoretically and experimentally. It is found that the classification characteristics of the first stage are well represented by the previous theory, which accounted for the effects of core and sheath air flows. It is also found that the classification characteristics of the second stage agree well with the theory based on potential flow calculations, to the extent that the flow rate ratio of core to total air flow is assumed to be determined by the critical trajectories of particles in the first-stage jet. The theory, however, must take into account the fact that the particles deviate to the center line in the acceleration zone. The separation characteristics, which affect the size distribution of the test aerosols produced by the impactor, are also found to be estimated by the individual separation characteristic of the first and the second stages.
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Isamu Kashiki, Akira Suzuki
1982 Volume 8 Issue 6 Pages
722-727
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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The relationship between the flocculation ability of a new type of flocculants,
i.e., the associated colloidal flocculants, and their solubility tendency in water was studied.
It was confirmed that the flocculation ability of the flocculants derives from the formation of their associated colloidal particles.
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Akira Suzuki, Isamu Kashiki
1982 Volume 8 Issue 6 Pages
728-733
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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The mechanism of the flocculation of kaolin suspensions by poly cations was studied. Experiments of adsorption and flocculation were carried out for the systems kaolin-methylene blue (mono cation) and kaolin-methyl glycol chitosan (poly cations).
The data showed that the adsorbed MGCh molecules had no segment extending into the liquid phase, and the optimum coverage fractions for flocculation on particle surfaces adsorbed by MB and MGCh were 0.35 and 0.03, respectively. Based on the above facts, it was proved that neither charge neutralization by adsorbed polymer nor interparticle bridging could be the mechanism leading to flocculation.
A new concept for the flocculation mechanism is proposed by considering the force acting between the surface elements for interaction of two particles and the uneven distribution of sites adsorbed by polymer flocculants.
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Tanaka Masato, O'Shima Eiji
1982 Volume 8 Issue 6 Pages
734-738
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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Experiments were performed to investigate the effect of the viscosity of the continuous phase on the stability of droplets in suspension polymerization of styrene.
An empirical equation was obtained to represent the dependence of the rate of coalescence and breakup of droplets on the viscosity of the continuous phase.
It was found that the rate of coalescence is lowered and a narrower particle size distribution is obtained by increasing the viscosity of the continuous phase.
Furthermore, it was presumed that a coalescence rate larger than 1.5×10
5 number/hr leads to agglomeration. With the usual stirring equipment of beaker scale the phase ratio can be raised to 0.67 by increasing the viscosity of the continuous phase.
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Masao Yokoyama, Toyohiko Hayakawa
1982 Volume 8 Issue 6 Pages
739-746
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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A multi-period planning model for decision of capacity and location of chemical plants was devised wherein the total discounted profit was maximized, taking account of plant construction cost and those of production, transportation, etc. Nonlinear costs, upper limit of plant construction capacity, and plant life were considered in the model.
The problem was formulated as a large-scale optimization problem containing a nonlinear function and 0-1 variables. The procedure of successive approximation by 0-1 mixed integer programming problem was proposed, and a partitioning procedure based on Benders' decomposition was developed in order to calculate it.
The situation of the planning model and the effectiveness of the calculation procedure are made clear through numerical examples.
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Masaharu Takao, Yasuhiro Murakarni, Jiro Koga, Yoshikazu Kuga, Kenji Y ...
1982 Volume 8 Issue 6 Pages
747-759
Published: November 10, 1982
Released on J-STAGE: November 12, 2009
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