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Tsuyoshi Munakata, Akira Matsuda, Kazunori Watanabe
1975 Volume 1 Issue 1 Pages
1-3
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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Experiments on vacuum distillation were made in a 2. 2 cm i. d. wetted-wall column 143 cm in length in a range of pressure from 0.05 to 2 mmHg by using three binary systems : ethyl oxalate (E. O.) -methyl salicylate (M. S.), methyl palmitate (M. P.) -di-
n-butyl phthalate (D. B. P.) and D. B. P.-di-
n-butyl sebacate (D. B. S.). The results obtained show the following facts. 1) The pressure drop data agree with the analytical equation in which a compressibility effect is considered. 2) For E. O.-M. S. and M. P.-D. B. P. systems (Surface tension positive), when reflux rate per wetted perimeter is over 0.0030.007 g/cm·sec the performance of the column is nearly equal to that predicted by the theoretical mass transfer rate in the vapor phase, but when the reflux rate is below that, lower efficiency results. 3) For D. B. P.-D. B. S. system (Surface tension negative), the performance comes down to 1/31/6 of that for the positive systems.
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Kikuko Hosoda, Iwao Takashima, Saichi Hatano
1975 Volume 1 Issue 1 Pages
4-8
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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Using beehive packings which were regular and had nowall effect, a relationship between
HOG and the reflux ratio γ (1 to ∞) was observed. Experimental conditions were as follows; tower diameter : 78 mm, packed height : 500 mm, sample : methanol-water system, determination of vapor concentration : differential condensation temperature method.
HOG varies largely depending on r when r is less than 10 and mass velocity of vapor
G is less than 60% of flooding velocity. This relation can be expressed by the following equations :
packing A (ε = 0.92)
HOG = 0.99 γ
-0.82packing B (ε = 0.90)
HOG =0.01
G 0.45 γ
-0.47When γ is greater than 10,
HOG approaches the values at total reflux.
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Shigeaki Kasaoka, Kyohei Hiramatsu, Yoshihisa Hamazaki
1975 Volume 1 Issue 1 Pages
9-13
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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In solid catalytic reactions and diffusion operations, a packed bed of cylindrical or ring-type solids as well as spherical solids is often employed, and these shaped solids have a distribution of diameter of length. However, no correlation expression for average mass transfer coefficient (
kf) in such cases has been published.
In the present work, the mass transfer rates of shaped benzoic acid (cylinders of equal or different diameter and length, spheres of different diameter, rings of equal diameter and length, and mixtures of spheres and cylinders) were measured by the dissolution into flowing water in the Reynolds number (
Re) range of 1 to 120, and the Schmidt number (
Sc) range of 346 (50°C) to 777 (30°C).
As a result, the equivalent diameter (
dps) based on the sphere of equal surface area was adopted as the representative dimension of packed solid, and the following equation for spherical solid of equal diameter was applied exactly for the above solid-fluid systems.
JD'= (
kf/u)
Sc1/2= 0.70
Re-0.61, 1 <
Re =
dpsuρ / μ<120
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Yoshiharu Murata, Fumitaka Sato, Sakae Tachikawa
1975 Volume 1 Issue 1 Pages
14-19
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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The mechanisms and rates of growth of
m CNB (chloronitrobenzene) and
p NT (nitrotoluene) from the binary melt of (
m CNB) - (
o CNB) and (
p NT) - (
mNT), respectively, have been investigated using an agitated vessel.
Crystals of both compounds grow by the stepwise mechanism as surface diffusion controlling, and in the case of
m CNB the screw dislocation mechanism is confirmed experimentally.
When the overall rate of growth is mainly controlled by the surface integration step, the following empirical equations are obtained :
mCNB
dW/
Adθ =2.00×10
11exp (-2.3×10
3/
RT) Δ
T2pNT
dW/
Adθ 5.64× 10
9exp (-19.3×10
3/
RT) Δ
T
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Takao Kokugan, Masaru Shimizu
1975 Volume 1 Issue 1 Pages
20-26
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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The results of theoretical and experimental studies of “packing effect” on separation of gas mixture by a packed thermal diffusion column are as follows : (1) from analytical discussions of batch system transport equation derived by Lorenz-Emery, it was found that
Ymax, which gave a maximum packing effect on separation, existed at
P≡
KDF/KCF<1, where
Y≡ω/√
k,
k is permeability of packing and w is half the distance between the plates. (2) continuous-flow transport equations for a packed thermal diffusion column were developed by the same method that Jones-Furry used for an open column. The developed equation agreed with the experimental data on the whole. (3) to investigate a series of packing effects on separation by packings, the relations of properties of packings between packing coefficiently and void fraction ε were obtained previously by hydraulic experiments. Both separation results of batch and continuous flow experiments were satisfied generally by the theoretical calculation, using the hydraulic relation.
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Toshisuke Sasakura, Nobuichi Ohi
1975 Volume 1 Issue 1 Pages
27-32
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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Dissolution of slightly soluble sulfates (Ca and Sr) suspended in water by cation exchange resin in H
+ form (Dowex 50 W) in a stirred vessel at 30°C was studied under the condition that mass transfer through the two liquid films adjoining salt and resin particles was rate-controlling.
Dissolution rate charts which relate bulk hydrogen ion concentration
CH to
krart, as a parameter α {=
ksas/ (
ksas+
krar)}, are presented.
The resin-side capacity coefficients
krar were determined under the condition that the salt-side resistance was negligible. The values of α and overall capacity coefficients
Ka (=α
krar) were determined graphically by comparison with the observed values of capacity coefficient for a wide range of salt to resin ratio (
W0/
m) with the value estimated from the charts mentioned above. Using the observed linear relation between
W0/
Ka and
W0/
m, the values of
krar0 and
ksas0 were determined from the slope and intercept, respectively, and the validity of
Ka were confirmed. The mass transfer coefficients obtained from the measured capacity coefficients were well correlated as functions of operating variables such as resin and salt particle size and rate of agitation.
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Hajime Unno, Ichiro Inoue
1975 Volume 1 Issue 1 Pages
33-38
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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A stochastic model of liquid mixing on perforated tray is applied to a mass transfer process. This model represents successfully the experimental results of the physical absorption or desorption process.
The relation between liquid mixing parameter and efficiency of mass transfer is simulated by this stochastic model. The results are as follows : 1) the efficiency of mass transfer is reduced by both of the Lagrangian time scale and the fluctuating velocity of liquid ; 2) the efficiency of mass transfer is affected more remarkable by the Lagrangian time scale than by the fluctuating velocity of liquid.
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Kazuo Aihara, Naohiko Ukawa, Mitsunori Hozawa, Teiriki Tadaki
1975 Volume 1 Issue 1 Pages
39-44
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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An experimental and theoretical study was attempted for the vaporization of water into a laminar flow of nitrogen gas in a wetted-wall column. Flow patterns and concentration profiles of gas phase were obtained, by solving the Navier-Stokes equations and diffusion equation numerically. In cocurrent gas-liquid flow fresh gas was always in contact with the liquid surface, whereas in countercurrent flow there existed a large circulation near the surface which blocked the contact.
It was concluded that the difference of flow patterns made overall mass transfer rate for cocurrent flow larger than that for countercurrent flow.
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Haruo Hikita, Haruo Ishikawa
1975 Volume 1 Issue 1 Pages
45-50
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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The rate of absorption of carbon dioxide into aqueous sodium carbonate-sodium bicarbonate solutions has been measured at 25°C in a 12.3 cm I. D. agitated vessel with a flat gas-liquid interface. Experiments have been carried out under conditions where gas absorption is accompanied by an irreversible pseudo-first order reaction. The experimental results have been analyzed by chemical absorption theory based on the Lévêque model and show good agreement with theoretical predictions for gas absorption with an irreversible pseudo-first order reaction between dissolved carbon dioxide and hydroxyl ions in carbonate-bicarbonate solution.
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Yasuhiko Tonooka, Ichiro Inoue
1975 Volume 1 Issue 1 Pages
51-56
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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Radial mixing phenomena in a packed bed are described by the two-dimensional dispersion model in an entrance region. To determine the mixing parameters such as radial dispersion coefficient, Peclet numbers and characteristic length, experiments of measuring the concentration distribution of matter dispersed continuously from a point source were made for packed beds of various heights.
From the experimental results, the radial dispersion was expressed as the function of Reynolds number and mean diameter of glass beads. The reciprocal of the Peclet number was proportional to the square of the apparent intensity of the turbulence. Further, the product of axial and radial Péclet numbers was nearly constant for Reynolds numbers above 50.
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Hiroshi Hara, Kazuo Endoh
1975 Volume 1 Issue 1 Pages
57-61
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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The effect of ultrasonics on settling velocity of suspended particles in water was studied. Pulse ultrasonic irradiation was much more effective than continuous irradiation. The settling velocity tends to decrease at an ultrasonic frequency of 200 kHz and increase at 1, 600 kHz. The measure of increase of settling velocity is expressed by
UR, the ratio of velocity of particles under pulse irradiation to that without irradiation.
UR=exp (α
I+β
T) :
dp>13,
c0 = 0.19 2.2 wt%,
I= (112) × 10
6 erg/cm
2 · sec where
I is ultrasonic intensity,
dp is diameter of particle,
c0 is concentration of particles in water,
T is number of pulse irradiation times and α, β are experimental constants.
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Shiro Ito, Toshio Kajiuchi, Hideo Oouchi
1975 Volume 1 Issue 1 Pages
62-67
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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Power consumption of mixing impellers has been described as the relation of power number
Np and Reynolds number
Re for Newtonian fluids.
In this paper, the generalized Reynolds number
Re for Bingham plastic fluids has been introduced from a theoretical consideration of the energy integral of the momentum equation for the flow system.
This generalized Reynolds number is expected to play the same role as Reynolds number for Newtonian fluids.
As a result, good correlations of
Re and
Np for mixing in Bingham plastic fluids have been obtained, the same as for the relation of
Re and
Np for Newtonian fluids.
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Shinji Nagata, Masabumi Nishikawa, Masamitsu Hattori, Takashi Kayama
1975 Volume 1 Issue 1 Pages
68-74
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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Heat transfer coefficient from a jacket wall to a half-ellipsoidal impeller, which was newly developed by the present authors, was studied in highly viscous Newtonian and non-Newtonian liquids.
It was experimentally confirmed that the impeller was effective in mixing of highly viscous liquid with least power consumption. In particular, an impeller useful as a heat transfer surface gave a high value of heat transfer coefficient.
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Yasuo Tamaki, Eiji Harada, Shiro Ito
1975 Volume 1 Issue 1 Pages
75-80
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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The behavior of liquid in the horizontal cylindrical agitated vessel is classified into two patterns, agitated state and annular state, and the transition from one to the other can be determined by the Froude number (
Fr=
Din2/g).
(
Fr)
c represents the transition Froude number from the annular to the agitated state and (
Fr)
a represents the transition Froude number from the agitated to the annular state.
(
Fr)
c and (
Fr)
a can be expressed by the following empirical equations containing impeller diameter (
Di), blade width (
W), number of blades (
B), vessel diameter (
Dt), vessel length (
L), and ratio of liquid volume (
ε).
(
Fr)
c = 30
Re-0.28 (
W/Di)
-1.0 B
γ (
L/Di) 0.8 (1-ε)
3.3 (
Dt/Di)
6.7(
Fr)
a = 26.5
Re-0.28 (
W/Di)
-1.0 (
L/Di)
2.5 (1-ε)
3.0 (
Dt/Di)
6.0γ=1.53ε-0.83
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Masayuki Nishinaka, Shigeharu Morooka, Yasuo Kato
1975 Volume 1 Issue 1 Pages
81-85
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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The radial distribution of holdup of gas bubbles was measured in fluid beds with diameter of 6.6, 12 and 19 cm by use of a small hot-wire probe. The radial distributions of holdup of gas bubbles are almost the same in the region of bed height where the effect of the distributor is considered to be negligible. The holdup of gas bubbles, εb, at radial distance γ from the center axis of the tower is expressed as
(
εbc-
εb/
εbc) = (
εbc-
εbw/
εbc) (γ/
R)
nwhere
εbc is holdup of gas bubbles at the center axis of the tower
εbw is holdup of gas bubbles extrapolated to the tower wall and
R is radius of fluid bed.
Furthermore, the relationships among (
εbc-
εbw) /
εbc or
n and the gas velocity and tower diameter were obtained.
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Akio Nishiwaki, Tokihiro Kago, Yasuo Kato, Shigenobu Tanaka, Takashi F ...
1975 Volume 1 Issue 1 Pages
86-91
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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Longitudinal mixing of liquid in multi-stage bubble columns was measured by a delta-response method for cocurrent and countercurrent operations. Response curves obtained were analyzed by the diffusion/ back-flow model, in which it was assumed that the diffusion model was applicable in each stage and there was back-flow between stages, and the back-flow ratio, β, was determined.
β in the range of 1.5 4.5 cm/sec of superficial gas velocity,
ug, is a function of both superficial liquid velocity and open area ratio of perforated baffle plates, and an empirical equation is obtained. β in the range of
ug>=13 20 cm/sec is approximated by two empirical equations, one for non pulsating flow region and other for pulsating flow region. β in the range of
ug=4.5 13 cm/sec can be read by the straight line which passes values of β on a log-log graph at
ug=4.5 cm/sec and
ug= 13 cm/sec calculated from the above equations.
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Tokuro Mizushina, Toshitatsu Matsumoto, Syuichi Morioka, Toshiyuki Fur ...
1975 Volume 1 Issue 1 Pages
92-98
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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An experimental study on cooling of hot air stream by liquid spray was made to obtain fundamental knowledge of spray quenching. Experiments were performed in a vertical downward flow of air in a 0.059 m diameter tube, and heat and mass transfer rate and pressure drop were studied. In this experiment, the maximum temperature drop during a contact time of 0.007 sec was 300°C. No effect of high mass flux upon the measured heat and mass transfer were observed within the accuracy of the experiment in the range of experimental conditions.
A theoretical approach was developed and good agreement was obtained between theoretical and experimental results. The theoretical calculations were carried out by using the mean volume-surface droplet diameter, and an equation of cooling efficiency is presented.
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Teruhiko Hoshino, Hirokazu Saito, Hiroshi Yukawa
1975 Volume 1 Issue 1 Pages
99-103
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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The effect of ultrasonic vibrations on free convective heat transfer from heated wire to water was experimentally investigated. Electrically heated platinum wire was placed horizontally in a stationary sound field of which the direction was horizontal or vertical. Deionized water degassed by boiling was used as sound medium.
The effect of ultrasonic vibrations on free convective heat transfer was expressed at the ratio of heat transfer coefficient with vibration to that without vibration. In the case of degassed water, there is a maximum value of heat transfer coefficient near the maximum value of acoustic radiation pressure and there is a minimum value of heat transfer coefficient near zero radiation pressure, but the increase of heat transfer coefficient with ultrasonic vibration was small.
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Toshiyuki Koya, Daizo Kunii
1975 Volume 1 Issue 1 Pages
104-109
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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Two kinds of pellets, of about 10 mm, made of ferric oxide powder and of Marcona powdery ore, were reduced to some extent by pure methane at temperatures of 770 1, 000°C, and the composition of exhaust gas was analysed.
For pellets of ferric oxide powder (hematite), fractional conversion of reduction was found to be nearly 95 per cent at 870°C, and carbon deposition was negligible before the total conversion attained 90 per cent. Conversion of methane of nearly 10 per cent was observed in the above case.
In case of 13.2 mm pellets of Marcona powdery ore, on the other hand, carbon deposition increased very much after total conversion of the pellet exceeded 55 per cent, and then nearly 45 per cent of methane was converted to carbon, carbon monoxide and hydrogen.
Difference of reduction behavior between the two kinds of pellets is discussed briefly, taking account of the difference of size distribution for the original fine powder.
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Yoshiharu Murata, Nobuyasu Meguri, Yukio Someya, Nobuetsu Yutani, Sige ...
1975 Volume 1 Issue 1 Pages
110-120
Published: January 10, 1975
Released on J-STAGE: October 21, 2009
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