Editor-in-Chief
Takao Tsukada (Tohoku University)

Associate (Editor-in-Cheifs)
Manabu Shimada (Hiroshima University)
Masahiro Shishido (Yamagata University)

Editors
Ryuichi Egashira (Tokyo Institute of Technology)
Jun Fukai (Kyushu University)
Choji Fukuhara (Shizuoka University)
Toshitaka Funazukuri (Chuo University)
Takayuki Hirai (Osaka University)
Jun-ichi Horiuchi (Kitami Institute of Technology)
Eiji Iritani (Nagoya University)
Yoshinori Itaya (Gifu University)
Noriho Kamiya (Kyushu University)
In-Beum Lee (Pohang University of Science and Technology (POSTEC))
Kouji Maeda (University of Hyogo)
Hideyuki Matsumoto (Tokyo Institute of Technology)
Nobuyoshi Nakagawa (Gunma University)
Masaru Noda (Fukuoka University)
Hiroyasu Ogino (Osaka Prefecture University)
Mitsuhiro Ohta (The University of Tokushima)
Eika (W. Qian Tokyo University of Agriculture and Technology)
Yuji Sakai (Kogakuin University)
Noriaki Sano (Kyoto University)
Naomi Shibasaki-Kitakawa (Tohoku University)
Ken-Ichiro Sotowa (The University of Tokushima)
Hiroshi Suzuki (Kobe University)
Nobuhide Takahashi (Shinshu University)
Shigeki Takishima (Hiroshima University)
Yoshifumi Tsuge (Kyushu University)
Tomoya Tsuji (Nihon University)
Da-Ming Wang (National Taiwan University)
Takuji Yamamoto (National Institute of Advanced Industrial Science and Technology (AIST))
Yoshiyuki Yamashita (Tokyo University of Agriculture and Technology)
Miki Yoshimune (National Institute of Advanced Industrial Science and Technology (AIST))

Editorial office:
The Society of Chemical Engineers, Japan
Kyoritsu Building, 4-6-19, Kohinata, Bunkyo-ku
Tokyo 112-0006, Japan
journal@scej.org

AIMS AND SCOPE:

Journal of Chemical Engineering of Japan, an official publication of the Society of Chemical Engineers, Japan, is dedicated to providing timely original research results in the broad field of chemical engineering ranging from fundamental principles to practical applications. Subject areas of this journal are listed below. Research works presented in the journal are considered to have significant and lasting value in chemical engineering.

Physical Properties and Physical Chemistry
Transport Phenomena and Fluid Engineering
Particle Engineering
Separation Engineering
Thermal Engineering
Chemical Reaction Engineering
Process Systems Engineering and Safety
Biochemical Food and Medical Engineering
Micro and Nano Systems
Materials Engineering and Interfacial Phenomena
Energy
Environment
Engineering Education

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Experiments of dense-phase pneumatic conveying of two fuel powders (Jinling petroleum coke and Huaibei anthracite coal) using nitrogen were carried out in an experimental facility including top-discharge and bottom-discharge blow tanks with design pressure up to 6.4 MPa. Petroleum coke and anthracite coal, which are widely used as attractive feed stocks for gasification, were chosen as conveying materials. The effect of blow tank type and powder properties on conveying characteristics at high pressure were investigated. Meanwhile, comparisons of conveying capacity, conveying stability and power consumption between these two kinds of blow tanks and the two fuel powders were made. The results indicate that the top-discharge blow tank has higher conveying capacity and better conveying stability, while the bottom-discharge blow tank has higher solid–gas ratio and lower power consumption. The anthracite coal has higher material mass flow rate and better conveying stability than petroleum coke due to its better flowability.

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Molecular dynamics simulation was used to investigate the permeation properties of a virtual condensable vapor through micropores. A permeation model was proposed to simulate the movement of condensable vapor through a micropore. The model is called “micropore filling phase permeation (MFP),” and the effect of feed gas pressure, pore size and pore size distributions on the vapor permeation properties was examined through model calculations. The observed permeance of ethane-like LJ particles at 260 K, a temperature below the critical temperature of real ethane, decreased stepwise at a specific pressure as the mean pressure was increased for micropores sized 0.8 and 1.1 nm in diameter. Analysis of the adsorption isotherm in the pores and vapor permeation simulations revealed the formation of a high-density liquid-like phase in micropores as the MFP caused a decrease in the mobility of permeating molecules. The model calculations based on the MFP showed qualitative agreement with the simulation results.

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A stable 12-phase alternating current (AC) arc has been successfully applied to melt granulated glass materials. The discharge behavior and the high temperature region of the plasma system can be controlled by the electrode configurations. In this study, the temporal characteristics of the arc discharge were examined by image analysis with a high-speed camera. The instabilities of particle surface temperature were investigated by a high-speed camera equipped with a band-pass filter system. This is the first time that particle temperature measurement of millisecond order has been performed by high-speed camera. Results show the amplitude of the variation in the in-flight particle temperature depends on the amplitude of the arc fluctuation. The periodicity of arc fluctuation is strongly related with transition of discharge pattern.

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This study investigates the dissolution kinetics of malachite using an ammonium citrate solution as an alternative leaching agent. The effects of several experimental parameters on the dissolution of malachite were investigated. A kinetic model to represent the effects of these parameters on the dissolution rate was studied. The dissolution rate was determined to increase with increasing solution temperature, concentration, stirring speed and decreasing particle size. Dissolution was observed to be controlled by the shrinking core model for surface chemical reactions. The activation energy of the dissolution process was determined to be 42.59 kJ/mol. The results indicate that the ammonium citrate solution could be used as an effective leaching agent for copper extraction from malachite.

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Confined Impinging Jet Reactors (CIJR) have become an important new reactor type used in the chemical industry and have been successfully applied in chemical plants. However, there have been few investigations on asymmetric CIJRs. In this work, the micromixing efficiency of an asymmetric T-shaped CIJR consisting of two tubes with inner diameters of 3 mm and 6 mm was investigated using a new parallel competing iodide iodate reaction. The effects of operating conditions such as impinging velocity and reagent concentration on the mixing performance were studied. The experimental results show that the segregation index X_S decreases with an increase in impinging velocity and impinging jets momentum ratio, and the decrease of acid concentration. Further, the distance between the axes of the jets and the top wall of the mixing chamber has a very complicated effect on the micromixing efficiency in the asymmetric CIJR. Based on the incorporation model and the experimental data, the micromixing time was estimated to be of the magnitude of milliseconds, confirming that the asymmetric CIJR possesses a superior micromixing efficiency.

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A fire whirl is known as a phenomenon that causes severe fire damage. A fixed-frame-type fire whirl generator is often used in fire whirl research, and it typically produces a weak fire whirl, whose flame height is determined almost solely by the heat feedback mechanism. The presence of a vortex above a pool fire changes the shape of the flame base and enhances the heat feedback from the flame to the fuel, increasing the burning rate, and hence the flame height. Since the burning rate of a fire whirl is determined by the nature of the vortex, its flame height should be able to be expressed as a function of vortex parameters, specifically, the circulation and the core radius of the vortex. This paper reports such a flame height correlation that was semi-empirically derived through a series of experiments, a computational fluid dynamics (CFD) simulation, and theoretical considerations.

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Biomass and its glucosamine content were measured for Monascus ruber after its cultivation on solid media containing different amounts of rice starch and protein. The protein was supplied as either yeast extract or peptone. The ratios of carbohydrate weight and protein weight (C/P ratio) in the media in this study were 2.2, 2.7, 20, 29, 34, and 60. Biomass production increased when the C/P ratio increased. The results show a linear relationship between the glucosamine content in biomass of M. ruber and the C/P ratio of media. We have successfully used this linear relationship to predict the glucosamine content in the biomass of M. ruber on rice flour medium. The error in this prediction method is not more than 15%.

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A novel semi-Lagrangian computational method has been developed in order to determine an accurate solution to the fluid mixing problem with a given velocity field in a T-shaped micromixer. Its trajectory-based fractional discretization scheme consists of a grid-based expression of a Laplacian with a spatial interpolation and a Lagrangian expression of convective transport by backward tracer particle tracking. The present numerical simulations provide high accuracy with negligible numerical diffusion for any grid orientations. The solutions to convective mixing in an engulfment flow regime of a T-shaped micromixer at Re=200 for various values of Sc from 1 to 1000 are compared with those obtained from a conventional grid-based method and a backward random-walk Monte Carlo method. The results of the proposed method are shown to agree well with those of the Monte Carlo method for all conditions, while the grid method presents large discrepancies due to unavoidable numerical diffusion at large values of Sc even with 16 million cells. It is demonstrated that the present method requires considerably lesser CPU time to achieve an accuracy equal to that obtained with the Monte Carlo method.

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Simulation of polymerization-induced phase separation of a polymer gel from a multifunctional monomer was carried out using the phase field method. To describe the driving force for phase separation, the interfacial energy between the polymeric phase and the aqueous phase was assumed to depend positively on the degree of polymerization, while the thickness of the interface at equilibrium and the mobility were assumed to depend negatively on it. The mobility was also assumed to depend negatively on the volume fraction of the polymer. A sigmoidal function was introduced to describe the nonlinear dependence of the mobility on the volume fraction. The wavelength of phase separation became finer as the polymerization rate increased when the rate of the reaction had a time scale similar to that of diffusion. When a nonreactive polymer coexists in the phase separation, the wavelength of phase separation shrinks because of suppression of diffusion caused by the coexisting polymer. These results qualitatively agreed with the experimental results for macroporous silica prepared via polymerization-induced phase separation.

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