Shinjuku, Japan
Shinjuku, Japan

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Yamada A.,Yokogawa Electric Corporation | Matsumoto H.,Tokyo Institute of Technology | Takagaki J.,Mitsui Chemicals Inc | Kawamura T.,Omega Simulation Co. | Yokoyama K.,Omega Simulation Co.
Journal of Chemical Engineering of Japan | Year: 2015

The dynamic simulation method based on the first principle model is considered to be useful especially when revision of the operation and control on experiences of plant engineers during run of the distillation plant is risky due to unstable behavior, use of unstable substances, complicated structure of the plant and so on. However, in the case of application of a conventional mirror modeling method in the Mirror Plant where the tray effciency is constant, the simulated temperatures before revising the control method are seen not to agree well with the observed plant data. We propose use of vapor temperatures for estimation of vaporization effciency for the equilibrium stage models by using the mirror modeling method in the Mirror Plant, which composes three system modes. In the case of adopting a time-variant model for the effciency, the simulated temperatures before revising the control method are seen to agree well with the observed ones. Then, it was simulated using the correlation model between vaporization effciency and vapor temperature adjusted for conventional control method whereby the periodical fluctuation can be stabilized after switching to the revised control method. Thus, the revised control method is implemented in the Distributed Control System, and it is observed that fluctuation of the vapor temperature became remarkably small. An application method of the vaporization efficiency based on temperature data is shown by dynamic simulation of remarkable periodical fluctuation of temperatures in a distillation column. Hence, it is made clear that the above-mentioned methodology for mirror modeling is useful and valuable for an improvement and verification of control loops for more stable operation of a plant. © 2015 The Society of Chemical Engineers, Japan.


Machida Y.,Omega Simulation Co. | Ootakara S.,Mitsui Chemicals Inc. | Seki H.,Tokyo Institute of Technology | Hashimoto Y.,Nagoya Institute of Technology | And 6 more authors.
IFAC-PapersOnLine | Year: 2016

A rigorous dynamic plant model of a vinyl acetate monomer (VAM) production was developed. This plant model enables the users to experience realistic plant operation, since it reflects the real plant characteristics and practical problems on the basis of experienced practitioners’ opinions. More importantly, the plant model provides a new benchmark problem; the users can investigate start-up/shutdown operation, plant-wide process control, fault detection and diagnosis, and others. Multiple scenarios prepared in the developed model cannot be simulated in conventional benchmark problems. The plant model can be used also for chemical engineering education. This advantageous plant model is released from Omega Simulation Co., Ltd. with a free limited license of Visual Modeler, which is a commercial dynamic simulator and can be linked with MATLAB®. This article aims to introduce the VAM plant model, the steady-state balance, various disturbances and malfunctions, and operation scenarios. © 2016


Yumoto T.,Omega Simulation Co. | Ootakara S.,Mitsui Chemical Inc. | Seki H.,Tokyo Institute of Technology | Hashimoto Y.,Nagoya Institute of Technology | And 3 more authors.
IFAC Proceedings Volumes (IFAC-PapersOnline) | Year: 2010

A dynamic simulator for the benchmark vinyl acetate (VAc) monomer production process is introduced. Rigorous first-principles dynamic models of the VAc process are implemented on the commercial software package Visual Modeler (Omega Simulation Co., Ltd.). The simulator employs pressure flow calculations and considers non-idealities in the process equipment, so that more realistic simulations are made possible, compared with the conventional simulators. The simulator's high performance calculation provides an environment where feasibility and performance of designed control systems can be efficiently evaluated without sacrificing high fidelity of the process model. The developed simulator will be made available in the public domain with a free limited license of Visual Modeler. © 2009 IFAC.


Yokoyama K.,Omega Simulation Co. | Matsuda H.,Nihon University | Kurihara K.,Nihon University | Tochigi K.,Nihon University
Kagaku Kogaku Ronbunshu | Year: 2012

Solubilities and tie line data were measured for seven ternary systems (methanol+water+n-butanol, n-propanol+water+n-butanol, n-propanol+water+n-amylalcohol, 2-propanol+water+n-amyl-alcohol, methanol+water+n-heptane, n-propanol+water+n-heptane, 2-propanol+water+n-heptane) using new experimental apparatus for liquid-liquid equilibria. NRTL parameters were determined using experimental tie line data and were confirmed by liquid-liquid equilibrium calculations of the components of both liquid phases from the feed components. © 2012 The Society of Chemical Engineers, Japan.


Matsuda H.,Nihon University | Kamihama N.,Nihon University | Kurihara K.,Nihon University | Tochigi K.,Nihon University | Yokoyama K.,Omega Simulation Co.
Journal of Chemical Engineering of Japan | Year: 2011

Isobaric vapor-liquid equilibria (VLE) were measured for four binary systems containing tetrahydrofuran (THF): THF+water, and three different mixtures of THF+n-alkane (n-pentane, n-hexane, and n-heptane). Measurements were conducted at pressures in the range 40.0-101.3kPa using a simple, automatic apparatus developed in our laboratory. From the experimental VLE data it was confirmed that the THF+water and THF+n-hexane systems formed minimum-boiling-point azeotropes, whereas the THF+n-pentane and THF+n-heptane systems were non-azeotropic mixtures. Non-random two-liquid (NRTL) parameters were also determined on the basis of the experimental VLE data. © 2011 The Society of Chemical Engineers, Japan.


Yokoyama K.,Omega Simulation Co. | Motohashi Y.,Nihon University | Matsuda H.,Nihon University | Kurihara K.,Nihon University | Tochigi K.,Nihon University
Journal of Chemical Engineering of Japan | Year: 2011

The compositions and the physical properties of mixtures are required to simulate multi-component batch distillation operations. In this study, temperature and accumulated distillate are measured as a function of time by use of a simple distillation apparatus. Initial compositions and physical parameters are estimated from this measurement data by a dynamic mathematical model, to examine the extent to which batch distillation operations can be predicted. For an ideal and a non-ideal solution system, the following three types of value estimation are examined: (I) compositions only, (II) parameters of one component, and (III) compositions and parameters of one component. The compositions could be estimated with sufficient accuracy. As for the physical properties, after devising a method for reducing the number of parameters, it is found that a batch distillation operation can be industrially designed from the estimated results. © 2011 The Society of Chemical Engineers, Japan.


Matsuda H.,Nihon University | Yokoyama K.,Omega Simulation Co. | Kyuzaki H.,Nihon University | Kurihara K.,Nihon University | Tochigi K.,Nihon University
Journal of Chemical Engineering of Japan | Year: 2010

Isobaric vapor-liquid equilibria for the ethylbenzene + p-xylene system at 40.00, 66.66, and 93.32 kPa have been measured using a modified Rogalski-Malanowski equilibrium still. Parameters for the NRTL equation are determined from the experimental vapor-liquid equilibrium data. In addition, the number of columns and the reflux ratio needed for separation by distillation are estimated. The separation performance can be partially evaluated, even if the mixture is assumed to be an ideal solution. However, we find that the temperature distribution in the distillation column differs, and that consideration of the activity coefficients affects the selection of the feed location. © 2010 The Society of Chemical Engineers, Japan.


Yokoyama K.,Omega Simulation Co. | Matsuda H.,Nihon University | Kurihara K.,Nihon University | Tochigi K.,Nihon University
Kagaku Kogaku Ronbunshu | Year: 2013

The Antoine constants and the NRTL parameters were determined for a system of water+ propyleneglycol monomethyl ether (PGME)+ propyleneglycol monomethyl ether acetate (PGMEA) using automatic vapor-liquid equilibrium measuring equipment. First, the NRTL parameters of a methanol+ ethanol+ water system and an acetone+ methanol+ water system were determined using the equipment. With these parameters, a distillate curve map was plotted to trace the vapor phase compositions of the residual curve map calculations, and this map was compared with the distillate trajectory of batch distillation. For the system of water+ PGME+ PGMEA, the distillate trajectory of batch distillation was examined by drawing the distillate curve map for the case in which the distillate in the region of liquid- liquid equilibrium was divided into two phases and the oil phase was returned to the still. These studies showed the possibility of evaluating batch distillation for systems with unknown physical properties using this equipment and the distillate curve map. © 2013 The Society of Chemical Engineers, Japan.

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