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Volume 12 (1986)
- Issue 6 Pages 627-
- Issue 5 Pages 499-
- Issue 4 Pages 375-
- Issue 3 Pages 251-
- Issue 2 Pages 127-
- Issue 1 Pages 1-
Predecessor
Volume 12, Issue 2
Displaying 1-21 of 21 articles from this issue
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Single fluidized bed mock-up test for gas-solid systemRyokichi Sugioka, Masami Takao, Kichiro Kaji, Mamoru Taniuchi, Toshiyu ...1986 Volume 12 Issue 2 Pages 127-132
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe KKI process, a new method for thermal cracking of vacuum residue, employs a particle circulation system between two fluidized beds, using an overflow system.
Regarding the particle circulation system, the most important points are to predict the particle circulation rate and to control this rate. So the characteristics of fluidization on the inclined fluidized bed were studied by single fluidized bed mock-up test for a gas-solid system. Formulas for predicting the void fraction and the pressure drop of gas in the inclined fluidized bed were obtained.View full abstractDownload PDF (769K) -
Toshio Kawaguchi, Toshihisa Wakasugi, Naosuke Hatano1986 Volume 12 Issue 2 Pages 133-139
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSTo determine optimum operating conditions of vinyl acetate synthesis from acetylene, a series of tests was conducted for about two years by use of an industrial fluidized reaction vessel of 3.28 m diameter and 50 ton/day vinyl acetate production capacity.
Assuming that the reaction rate was proportional to the partial pressure of acetylene, the rate and rate constants were studied by comparing the plug flow model with the complete mixing flow model. It was found that vinyl acetate synthesis by use of zinc acetate carbon catalyst in a large fluidized reaction vessel appeared to show complete mixing because the reaction rate constant determined from the observed conversion remained constant irrespective of reaction conditions.View full abstractDownload PDF (986K) -
Kunio Kato, Kozo Ebara, Shinji Takahashi, Masatoshi Tanizawa, Hiroyuki ...1986 Volume 12 Issue 2 Pages 140-145
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSTo classify fine particles (less than 40 μm), a sonic fluidized bed particle classifier was invented. In this classifier, fine particles were classified by elutriation phenomena from the fluidized bed. To protect cohesion of fine particles, the sound waves of 10-300 Hz were generated below the gas distributor and stirrers were installed in the free board. To transmit the sound waves to the fluidized bed, filtration cloths were used as the gas distributor. Fly-ash particles (1-50 μm) and silicon carbide particles (1-20 μm) were continuously classified.
Very fine particles which cannot be fluidized by an ordinary fluidized bed could be continuously classified by this classifier. The characteristics of particle classification of this classifier are expressed by a partial separation efficiency, and good correlation between particle separation efficiency and operating conditions was obtained. If one size was 1.5 times larger than the other, these two sizes were classified with good efficiency by this classifier.View full abstractDownload PDF (867K) -
Koichi Yamamura, Mitsutoshi Nakajima, Hisayoshi Matsuyama1986 Volume 12 Issue 2 Pages 146-152
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe problem of detection of gross errors in process data obtained in the steady state of a continuous process is formulated as the problem of selecting the optimal statistical model that minimizes Akaike's Information Criterion subject to mass and heat balances. This formulation makes it possible to construct an efficient algorithm for detection of gross errors utilizing a branch-and-bound technique. The efficiency of this algorithm is demonstrated by applying it to numerical experiments with the use of a simplified refinery model with 22 flowmeters.View full abstractDownload PDF (831K) -
Hidemitsu Hojo, Ken Tsuda, Makoto Arai, Yoshikazu Kano1986 Volume 12 Issue 2 Pages 153-158
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSBehavior of flame propagation and of quenching in a circular pipe were investigated to establish design criteria for a flame arrester.
Effects of ignition energy, sealing condition of pipe ends, pipe diameter and length on the behavior of flame propagation were studied. Among these factors, sealing condition of pipe ends and length showed significant effects on flame velocity.
Flame quenching experiments by wire gauze arrester showed that estimation of the flame velocity through the arrester was important in considering the quenching ability. It was concluded that the critical flame velocity should be estimated as a few meters per second for an open-end system, and a very high value for an in-line system. The arrester should be set near the ignition point where the flame propagates with low velocity.View full abstractDownload PDF (2710K) -
Masayoshi Kubota, Kazuyuki Itoh, Harumi Matsuzaki, Kenkichi Izumi, Yas ...1986 Volume 12 Issue 2 Pages 159-164
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe effect of surface potential of particles on removal characteristics in the HGMS were studied by using three kinds of small particles with individually different magnetic susceptibility : molybdenum, chromium and hematite. It was shown that the effect of surface potential of particles such as molybdenum with low magnetic susceptibility value less than 1.7× 104 appeared at a low linear velocity of liquid less than 150 m/h, and the removal performance increased by controlling the pH range in which the product of ζ-potential of the particle and matrix was negative.
The relation between the particles volume captured with matrix and the rest potential of the matrix was determined.View full abstractDownload PDF (938K) -
Soo Kag Lee, Hitoki Matsuda, Masanobu Hasatani1986 Volume 12 Issue 2 Pages 165-171
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSFor rate enhancement of thermal energy storage by means of Ca (OH)2/CaO reversible thermochemical reaction, the dehydration behaviour of Ca (OH)2 was studied under reduced pressure conditions (2.33-101.3 KPa). It was found that the initiation temperature of the dehydration of Ca (OH)2 was lowered by reducing the pressure in the reaction system and that the dehydration rate increased in inverse proportion to the pressure in the system.
The overall reaction rate expression under static conditions was obtained by non-isothermal reaction analysis at various constant heating rates. The reaction orders with respect to a solid reactant and to water vapour pressure were found to be 0th and 0.5th, respectively. The apparent rate constant determined was relatively well correlated with the total pressure in the reaction system within the experimental conditions employed in the present study.
The enhancement of the dehydration of Ca (OH)2 by reducing the pressure in the reaction system was quantitatively estimated.View full abstractDownload PDF (901K) -
Tsuyoshi Munakata, Katsumi Honda1986 Volume 12 Issue 2 Pages 172-178
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSA theoretical analysis of the partial condenser is proposed. Based on the two-film theory, its feature lies in expressing the vapor or liquid composition in the condenser related to the local flow rate of condensate. The results are more comprehensive for use in design calculation than are those of previous investigators, since the position in the condenser can be related and other there are analytical advantages. For the case of the linear equilibrium relation, the solution is given with two parameters : the mass transfer resistance ratio of liquid to vapor phases and the ratio of the condensation flux to the overall mass transfer coefficient. The well-known Rayleigh solution and another extreme case where the mass transfer resistances in both the liquid and vapor phases vanish are explained in relation to the solutions.
A numerical example on the operating line in a partial condenser is shown. The present method gives reasonable results compared with the few other methods.View full abstractDownload PDF (1066K) -
Yasuo Fukuwatari, Yoshitaka Tamura, Teruhiko Mizota, Mamoru Tomita, Sh ...1986 Volume 12 Issue 2 Pages 179-184
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSNew equations for membrane transport as well as for concentration polarization were introduced in order to analyze the process of the reverse osmosis concentration of cheese whey, a multi-component system. The present equations were derived and simplified from those for multi-component systems, employing total solute molarity instead of molar concentrations of individual components, and the averaged solute permeability and mass transfer coefficient.
To appraise the new equations, batch-wise concentration of fresh cheese whey was carried out by using RO membrane of 90 % salt rejection rate, installed in a plate-and-frame module, under the following conditions : operating pressure, 3.9 MPa; recirculation flow rate, 0.9 m3 h-1; temperature, 10°C.
The water flux and total solute flux calculated from the equations were in good accord with experimental data up to fourfold concentration of the cheese whey. Simultaneously, solute concentration on the membrane surface of the higher-pressure side was also calculable by means of the equations.View full abstractDownload PDF (795K) -
Shoji Tanno, Takeshi Kawasaki, Takatoshi Miura, Shigemori Ohtani1986 Volume 12 Issue 2 Pages 185-191
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe deposition rate of droplets on the wall of a spray chamber was measured while varying the atomizing air (Ma) and liquid (Ml) flow rates, the ambient air flow rate (Ms) and the ratio of length to diameter of the spray chamber. The deposition rate increases with the atomizing air flow rate at Ms/ (Ma+Ml) <50 and then does not depend on the Ma at Ms/ (Ma+Ml) ≥ 50.
The deposition rate was also calculated by using a turbulence model of two k-ε equations and a Particle Source In Cell (PSI) model. The following measurements near the spray nozzle exit were carried out to give the initial values of the computation : radial distributions of spray dispersion, drop size and velocity components of the ambient and droplet flows. Good agreement can be obtained between the calculated and the measured deposition rates.View full abstractDownload PDF (992K) -
Jusuke Hidaka, Shigeo Miwa, Kazutaka Makino1986 Volume 12 Issue 2 Pages 192-198
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe generating mechanism of sound in shear flow of a granular material was studied by applying powder mechanics and acoustic theory. In shear flow, rupture layers are formed periodically in the granular bed. The sound field generated by the formation of rupture layers was estimated on the basis of the model of sound radiation from a piston in an infinite wall. The sound pressure waveform agrees well with the measured one. This result shows that the sound parameters closely relate to the frictional properties and the formation of rupture layers.View full abstractDownload PDF (2868K) -
Shiro Kishihara, Satoshi Fujii, Masahiko Komoto, Hajime Tamaki, Syoich ...1986 Volume 12 Issue 2 Pages 199-205
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSClarification of diluted molasses through a dynamic membrane (a self-rejecting membrane) which was formed on a porous ceramic tube under pressure was carried out and performance of the membrane was studied.
The flux declined and the rejection of colored substance rose with prolonged permeation time, and formation of the self-rejecting membrane became almost steady after about two hours. The thickness and tightness of the self-rejecting membrane could be controlled by circulation rate and operating pressure, respectively. It could be supposed that at a level of rejection of 0.9 the cut-off molecular weight of the self-rejecting membrane formed was 40, 000 or 20, 000 at an operating pressure of 0.5 MPa or 2 MPa, respectively.
The flux through the self-rejecting membrane was above four times that through an asymmetric organic membrane although the rejection of colored substance through the self-rejecting membrane was lower. The flux of Bx 50° molasses was 20 1· m-2· h-1 at 60°C, 0.2 MPa operating pressure and 4m · s-1 circulation rate, and the rejection of colored substance was 0.1. Turbid and suspended substances in molasses which cannot be satisfactorily removed by means of Celite filtration or centrifuging were completely removed by ultrafiltration through the self-rejecting membrane. The taste of permeate was remarkably improved in comparison with that of the original molasses.View full abstractDownload PDF (925K) -
Kunihisa Osasa, Masao Sambuichi, Hideo Nakakura1986 Volume 12 Issue 2 Pages 206-212
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSElectroflotation experiments were carried out with flocculated suspensions under liquid batch and gas continuous conditions. Cellulose, kaolin and water works sludge were used as solids samples and polyacrylamide as polymeric flocculant. The effects of the kind of solids, of the floc characteristics, and of the magnitude of electric current on the separation process were examined experimentally.
The character of the floc surface, e.g. wettability, roughness and shape, determined the ease with which the process could be brought about. The length of time required to float a floc showed an approximately inverse relationship with the product of its diameter and the magnitude of current and was related to the length of time taken for a floc to become neutrally buoyant by bubble attachment. Hence increasing the magnitude of current and the average diameter of floc resulted in an increase in the rate of separation.View full abstractDownload PDF (1006K) -
Chiaki Kuroda, Kohei Ogawa, Ichiro Inoue1986 Volume 12 Issue 2 Pages 213-218
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSA method for measuring concentration of helium gas in turbulent air flow by using hot-wire anemometry and the suction method at constant pressure was investigated in order to utilize it for studying experimentally the turbulent gas mixing process.
The necessary conditions for a measuring probe which can accurately detect concentration fluctuation were clarified experimentally. A probe made for trials is sufficient for measurements in a gas flow of around 5 m/s; i.e. the relationship between the concentration of helium and the output of CTA is a monotonous increasing function, and the accuracy of measurement and the response rate for concentration fluctuations are about 0.005 and 300 Hz respectively at a suction velocity of 5 m/s.View full abstractDownload PDF (761K) -
Hitoshi Takase, Shoji Tsuri, Masunori Sugimoto, Hiroyuki Tanaka, Hiros ...1986 Volume 12 Issue 2 Pages 219-248
Published: March 10, 1986
Released on J-STAGE: November 12, 2009
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1986 Volume 12 Issue 2 Pages 249a
Published: 1986
Released on J-STAGE: November 22, 2010
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1986 Volume 12 Issue 2 Pages 249b
Published: 1986
Released on J-STAGE: November 12, 2009
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1986 Volume 12 Issue 2 Pages 249c
Published: 1986
Released on J-STAGE: November 22, 2010
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1986 Volume 12 Issue 2 Pages 249d
Published: 1986
Released on J-STAGE: November 22, 2010
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1986 Volume 12 Issue 2 Pages 249e
Published: 1986
Released on J-STAGE: November 22, 2010
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1986 Volume 12 Issue 2 Pages 249f
Published: 1986
Released on J-STAGE: November 22, 2010
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