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Predecessor
Volume 11, Issue 1
Displaying 1-16 of 16 articles from this issue
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Masahiro Kamata1985 Volume 11 Issue 1 Pages 1-6
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSA theoretical and experimental investigation was performed to determine the drift velocity of an oil slick on water surface in the presence of water waves. The oil slick was assumed to be thick and highly viscous, so that it does not stretch in response to the periodical wave motions. Measurements of the drift velocities were made by substituting thin plastic films in place of the oil slicks. Theoretically, the drift velocities were derived by assuming zero net force within the boundary layer under the oil slick. The boundary layer should be considered turbulent, according to the analysis of the experimental results.View full abstractDownload PDF (859K) -
Mitsuaki Hirota, Atsushi Fudoh, Yoshiteru Mizuno, Toshio Oshima1985 Volume 11 Issue 1 Pages 7-12
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe effects of the flowability of dust and of dislodging methods on the permeability of air and on dust penetration through the filter were examined by means of an unused filter and a dislodged filter with four kinds of powder. It was shown that flowability of the dust affected the collection mechanism of the filter cloth. For a low-flowable dust, most dust particles were collected at the surface of the filter cloth, and few particles entered into the filter cloth. Therefore, the characteristic of collection by the dislodged filter cloth was similar to that by the unused filter.
On the other hand, for a high-flowable dust a portion of the dust particles entered into the filter cloth. In this case, a fraction of the dust particles collected in the filter cloth remained in it after dislodging, and so the permeability of air and the mass of dust penetrating the dislodged filter cloth were affected significantly by the dislodging methods and the mass of dust remaining in the filter cloth.View full abstractDownload PDF (925K) -
Yoshikazu Kuga, Jiro Koga, Kenji Yamaguchi, Ichiro Inoue1985 Volume 11 Issue 1 Pages 13-19
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSA fundamental experiment was carried out to analyze the comminution kinetics of a screen mill, and the size distribution of products by one collision against the impact plate was measured. Particles used were Soma sand and Neobead. Impact velocity was 15.7, 32.3, 47.1 and 61.6 m ·s-1. The size distribution of products was approximately expressed by the Rosin-Rammler equation. The parameters of distribution were almost independent of the size of feed particles and were a function of impact velocity. The crushing efficiency, defined as the ratio of the increase of area to the kinetic energy, tended to take a maximum against the impact velocity.
The breakage probability was approximately expressed by the Weibull distribution function of the feed particle size and the impact velocity. The breakage function was described as the Rosin-Rammler equation. The first-order approximation of both functions could be given as the 2nd-4th power function of particle size. They had the same tendency with the selection and breakage functions of the screen mill, and useful fundamental data to investigate the comminution in a screen mill were obtained by this experiment.View full abstractDownload PDF (935K) -
Shigehisa Endoh, Kenji Yamaguchi, Shoichi Okamoto1985 Volume 11 Issue 1 Pages 20-26
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSMagnetite slurry was filtrated with three kinds of nickel sponge magnetic filter under several conditions of filtrate velocity (0.01-0.1 m/s), thickness of filter (0.01-0.2 m) and applied magnetic field (3.98 × 104 and 7.96 × 104 A/m). After a given duration of magnetic filtration, the filter was cleaned by backwashing water, whose velocity uω was changed from 0.02 to 0.1 m/s. The mass ratio of particles discharged from the filter to those collected in the filter ηd was measured and the effects of those conditions on ηd were examined. For the filter of greater foam size, the performance of renewal was not influenced by the filtration conditionsηd was about 10-20 % where uω =0.03m/s. On the other hand, for the filter of 0.3mm foamsize, the effects of uω were remarkable and ηd attained 70 % where uω=0.05 m/s. Size of particles removed in backwashing water increased to 2-5 times the feed magnetite size.View full abstractDownload PDF (873K) -
Koichi Asano, Shigeru Matsuda1985 Volume 11 Issue 1 Pages 27-33
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSMeasurements of the rates of heat and mass transfer for condensation of binary vapor mixtures of the methanol-water system on a small vertical flat plate under both total and partial condensation conditions were made. The surface temperatures of the liquid film showed good agreement with the bubble points of the liquid for both total and partial condensation conditions. Vapor-phase sensible heat fluxes and diffusion fluxes showed good agreement with predictions by a laminar boundary layer theory. Condensation heat transfer coefficients defined by the temperature difference between the interface and the wall showed good agreement with predictions by the Nusselt model with due consideration to physical properties of the condensate. Studies of the critical conditions for transition to total and partial condensation were also made.View full abstractDownload PDF (990K) -
Harumi Matsuzaki, Sankichi Takahashi, Masayoshi Kubota, Katsuya Ebara, ...1985 Volume 11 Issue 1 Pages 34-40
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe characteristics of fine Fe-compound particle removal by an HGMS with fibre matrix are studied.
The removal efficiency, R, of the particles by the HGMS is expressed as follows :
1-R=1n(631k*β)n, β=ε·h/d**·(1-ε)/uL·uM/uG
where k* is equivalent mass transfer rate and n is a constant. The particle concentration gradient, dX/dx, in the matrix is independent of C and depends on x.
The equivalent mass transfer rate, k*, is dependent on the particle diameter, d. When d is less than 1 μm, k* equals 2.2 × 10-7 cm/s and when d is greater than 1 μm, k* depends on the particle form, i.e. k* is 1.27 × 10-7 cm/s for particles without protrusion and is 2.83 × 10-6 cm/s for particles with protrusion. But when uL/ε(1-ε) is greater than 224 cm/s, R decreases because of the through-pass phenomenon in the matrix.View full abstractDownload PDF (3100K) -
Osafumi Fujimoto, Hakuai Inoue1985 Volume 11 Issue 1 Pages 41-47
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe rate of water vapor adsorption on porous Vycor glass was measured and the mechanism of the adsorption process was analyzed.
The adsorption of water vapor on Vycor was divided into two different types of adsorption : physical adsorption and chemisorption. Physical adsorption accounted for most of the total adsorption at room temperature. It proceeded rapidly and the rate was determined by the internal diffusion control.
Comparing the experimental values with the theoretical sorption curve, the internal diffusion coefficient was obtained. It could be shown that the contribution of surface diffusion to the total diffusion was so large that Knudsen diffusion was negligible. The observed surface diffusion coefficient changed with the amount of sorbate adsorbed on Vycor.
The rate of chemisorption could well be expressed by the Elovich equation.View full abstractDownload PDF (1038K) -
Hiroaki Masuda, Shuji Matsusaka, Shunya Ikumi1985 Volume 11 Issue 1 Pages 48-54
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSParticle reentrainment caused by an air stream was investigated both experimentally and theoretically. Fine particles, mainly fly-ash, were packed into a concavity on the inside wall of a rectangular channel with various packing fractions, and reentrained by an air stream. Behavior of particles on the powder bed was observed by a TV monitor and recorded on a videotape. It was found that the particles reentrained were mainly aggregates, and that the reentrainment velocity increased with increasing packing fraction or decreasing diameter of the primary particles in the powder bed. It was also found that the higher the packing fraction or the smaller the diameter of the primary particles, the smaller the diameter of aggregate particles reentrained. The tensile strength of the powder bed, calculated by use of Rumpf's equation and the van der Waals force, correlated well with the critical shear stress at which particle reentrainment began. Furthermore, the dependence of the reentrainment flux (number of reentrained aggregate particles per unit area and unit time) on the air velocity was found to be qualitatively explained by the frequency of turbulent bursts.View full abstractDownload PDF (899K) -
Kazuhisa Ohtaguchi, Ichiro Inoue1985 Volume 11 Issue 1 Pages 55-62
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe objective of this article is to present a functional design method for culture systems to handle growth, sugar consumption, and lactic acid production processes of yogurt starter St. thermophilus. In the first part, a conceptual scheme to represent the totality of cellular function of the batch growing microorganism was pictured with functional blocks which suggested the necessity of including the cellular function of inocula in the processing parameters of batch cultures.
Experiments described in the next part were done with a sequential fermentation process utilizing a chemostat as the preculture vessel and a batch fermentor as the main culture apparatus. Dilution rate of the chemostat was varied in nine steps in the range between 0.034 and 1 1/h, and cells from such a steady-state chemostat were inoculated into batch cultures. It was found that the cellular state of inocula have a marked effect on the subsequent batch growth and acid production processes of St. thermophilus.
Specific rates of cellular growth, lactose consumption, and lactic acid production as well as final concentrations of cell mass and acid in cultures were related to cellular functions of inocula with synthesized dimensionless parameters.View full abstractDownload PDF (1284K) -
Case of the Michaelis-Menten type reactionMitsuo Sakata, Shintaro Furusaki1985 Volume 11 Issue 1 Pages 63-69
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSNumerical calculations were carried out to investigate the influence of intraparticle diffusion on reactions inside immobilized-enzyme particles under compaction in a packed column.A two-dimensional diffusion model was proposed for partial regions, where each region in cludes one contact surface. Concentration profiles were obtained for the case of the MichaelisMenten kinetics by using the finite difference method and/or the finite element method.
The effect of compaction on reaction was estimated in terms of the effectiveness factor. From these results, it was found that the effectiveness factor decreases with increasing contacting area and the general modulus. An approximate expression for the effectiveness factor was developed by using the method previously proposed by Kobayashi et al.View full abstractDownload PDF (1062K) -
Masao Sudoh, Tadahisa Sasase, Takumi Yonebayashi, Kozo Koide1985 Volume 11 Issue 1 Pages 70-76
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSOxidative degradation of aqueous phenol effluent was achieved with Fenton's reagent ofhydrogen peroxide and ferrous ion. Effects of concentrations of phenol, hydrogen peroxide and ferrous ion, pH and reaction temperature on degradation rate of phenol were experimentally examined. pH was kept constant by a pH-stat instrument during the reaction. Degradation rates of phenol were arranged with the first-order reaction of phenol with rate constant such that k=Aexp (-E/RT) [Fe2+] α [H2O2] β at different pH values.
Oxidation products were analysed with a high-performance liquid chromatograph and identified with catechol, hydroquinone and ρ-quinone, which were oxidized successively to muconic acid and maleic acid. Oxidation efficiency showed higher values at pH 3, 4 and when reaction temperature was increased. In conclusion, operation in the range of pH 3-4.5 is effective from considerations of degradation rate and oxidation efficiency.View full abstractDownload PDF (904K) -
Toshiro Murase, Hideo Nakakura, Hidetoshi Mori, Mompei Shirato1985 Volume 11 Issue 1 Pages 77-83
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSA method for analysing final moisture content of a granular bed under gravitational and centrifugal drainage is studied.
The effect of final equilibrium saturation profile on final moisture content is shown in terms of equivalent capillary drain height, taking into account the driving force of drainage. An equation for the capillary pressure curve is derived on the basis of Haring's statistical pore model to determine the capillary drain height, thus providing an easy method for calculation of the final saturation profile and the average residual saturation of a granular bed. The final, equilibrium moisture content can be accurately evaluated from calculation of a newly defined capillary number, J·N cap. Predicted results agree well with experimental results for gravitational and centrifugal drainage of incompressible granular beds of glass beads, Soma standard sand, and calcium carbonate particles of diameter 76-811 μm.View full abstractDownload PDF (1143K) -
Jun Fukai, Minoru Watanabe, Takatoshi Miura, Shigemori Ohtani1985 Volume 11 Issue 1 Pages 84-92
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSA new method, which utilizes the non-linear least squares method, is proposed to estimate simultaneously the thermal conductivity, the heat capacity and their temperature coefficients. This measurement principle is further expanded so as to measure the heat of chemical reaction. In the measurement, a hollow cylinder is heated from both the central axis and the outer surface. It is found that the optimum location of the minimum temperature in the specimen should be in a middle part between the center and the outer surface in order to reduce measurement error. The effective thermal conductivity and the heat capacity of a packed bed of glass and aluminum oxide are measured from 300 K to 700 K at a heating rate of 2-3 K/min. The endothermic quantity of transition (KNO3) and dehydration (CaC2O4·H2O) are also measured at a heating rate of 2 K/min. The results agree well with those determined by other measuring techniques. By using this method, therefore, the thermal conductivity, heat capacity and heat of reaction which are necessary to solve heat conduction problems can be determined simultaneously.View full abstractDownload PDF (1271K) -
Ryokichi Sugioka, Shoichi Kikuchi, Kichiro Kaji, Masami Takao1985 Volume 11 Issue 1 Pages 93-98
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSA model for predicting the driving force of particle circulation between two fluidized beds was developed by use of experimental data on a KKI process pilot plant with a capacity of 30 BPSD vacuum residue feed. KKI process is a new process in which vacuum residue is decomposed thermally into lighter oils in a fluidized bed of pulverized iron ores and, at the same time, iron ore particles covered with decomposed petroleum coke are reduced to sponge iron in a reduction furnace. The model shows that the circulation driving force is obtained by the difference of static pressure between the fluidized bed reactor and a cross-pipe which connects the two fluidized beds. Then, it was shown that both the circulation rate and the direction of circulation can be controlled by the change in feed rate of steam to fluidized bed and cross-pipe.View full abstractDownload PDF (763K) -
Masato Tanaka, Takashi Izumi, Eiji O'shima1985 Volume 11 Issue 1 Pages 99-106
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSIn suspension polymerization of styrene, deposition of polymer onto the baffle and wall of the stirred-tank reactor was measured. As a stabilizer, polyvinyl alcohol was used.
The following points were found.
1) Rate of deposition increases with the progress of polymerization and reaches the maximum at about 3 hrs after the beginning of reaction.
2) The transient feature of the deposition rate in the course of time is the same as that of the rate of coalescence between droplets in suspension polymerization of styrene.
3) Increase of the viscosity of continuous phase by addition of the viscous fluid decreases deposition.
4) Increase of stabilizer concentration decreases deposition.
5) Over 80 % of overall deposited amount deposits during 4 hrs after the beginning of reaction.
6) Deposited amount is at its minimum for Reynolds numbers between 3 × 104 and 3.6 × 104.
7) Deposited amount increases as the impeller height closes to the liquid surface.View full abstractDownload PDF (996K) -
Isami Yoshifuku, Katsuroku Takahashi, Masami Kato, Kahoru Hirayama, Hi ...1985 Volume 11 Issue 1 Pages 107-125
Published: January 10, 1985
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSDownload PDF (2422K)
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