Simulation of DME synthesis from coal syngas by kinetics model

다국어 초록 (Multilingual Abstract)

DME (Dimethyl Ether) has emerged as a clean alternative fuel for diesel. There are largely two methods
for DME synthesis. A direct method of DME synthesis has been recently developed that has a more compact process
than the indirect method. However, the direct method of DME synthesis has not yet been optimized at the face of its
performance: yield and production rate of DME. In this study it is developed a simulation model through a kinetics model
of the ASPEN plus simulator, performed to detect operating characteristics of DME direct synthesis. An overall DME
synthesis process is referenced by experimental data of 3 ton/day (TPD) coal gasification pilot plant located at IAE
in Korea. Supplying condition of DME synthesis model is equivalently set to 80 N/㎥ of syngas which is derived from
a coal gasification plant. In the simulation it is assumed that the overall DME synthesis process proceeds with steadystate,
vapor-solid reaction with DME catalyst. The physical properties of reactants are governed by Soave-Redlich-
Kwong (SRK) EOS in this model. A reaction model of DME synthesis is considered that is applied with the LHHW
(Langmuir-Hinshelwood Hougen Watson) equation as an adsorption-desorption model on the surface of the DME catalyst.
After adjusting the kinetics of the DME synthesis reaction among reactants with experimental data, the kinetics
of the governing reactions inner DME reactor are modified and coupled with the entire DME synthesis reaction. For
validating simulation results of the DME synthesis model, the obtained simulation results are compared with experimental
results: conversion ratio, DME yield and DME production rate. Then, a sensitivity analysis is performed by
effects of operating variables such as pressure, temperature of the reactor, void fraction of catalyst and H2/CO ratio of
supplied syngas with modified model. According to simulation results, optimum operating conditions of DME reactor
are obtained in the range of 265-275℃ and 60 kg/㎠. And DME production rate has a maximum value in the range
of 1-1.5 of H2/CO ratio in the syngas composition.

다국어 초록 (Multilingual Abstract)

DME (Dimethyl Ether) has emerged as a clean alternative fuel for diesel. There are largely two methods
for DME synthesis. A direct method of DME synthesis has been recently developed that has a more compact process
than the indirect method. However, the direct method of DME synthesis has not yet been optimized at the face of its
performance: yield and production rate of DME. In this study it is developed a simulation model through a kinetics model
of the ASPEN plus simulator, performed to detect operating characteristics of DME direct synthesis. An overall DME
synthesis process is referenced by experimental data of 3 ton/day (TPD) coal gasification pilot plant located at IAE
in Korea. Supplying condition of DME synthesis model is equivalently set to 80 N/㎥ of syngas which is derived from
a coal gasification plant. In the simulation it is assumed that the overall DME synthesis process proceeds with steadystate,
vapor-solid reaction with DME catalyst. The physical properties of reactants are governed by Soave-Redlich-
Kwong (SRK) EOS in this model. A reaction model of DME synthesis is considered that is applied with the LHHW
(Langmuir-Hinshelwood Hougen Watson) equation as an adsorption-desorption model on the surface of the DME catalyst.
After adjusting the kinetics of the DME synthesis reaction among reactants with experimental data, the kinetics
of the governing reactions inner DME reactor are modified and coupled with the entire DME synthesis reaction. For
validating simulation results of the DME synthesis model, the obtained simulation results are compared with experimental
results: conversion ratio, DME yield and DME production rate. Then, a sensitivity analysis is performed by
effects of operating variables such as pressure, temperature of the reactor, void fraction of catalyst and H2/CO ratio of
supplied syngas with modified model. According to simulation results, optimum operating conditions of DME reactor
are obtained in the range of 265-275℃ and 60 kg/㎠. And DME production rate has a maximum value in the range
of 1-1.5 of H2/CO ratio in the syngas composition.

참고문헌 (Reference)

• 1 K. Fujimoto, 2051-, 1984
• 2 G. H. Graaf, 41 : 2883-, 1986
• 3 G. Soave, 27 : 1197-, 1972
• 4 Q. Sun, (171) : 301-, 1998
• 5 H. T. Zhang, 27 : 198-, 2001
• 6 X. D. Peng, 54 : 2787-, 1999
• 7 P. Villa, Frozatti, 24 : 12-, 1985
• 8 K. Klier, 1982
• 9 W. Seyfert, 57 : 482-, 1980
• 10 I. Dybkjaer, 1988
• 11 Z.G. Nie, 14 : 22-, 2005
• 12 한명완, "반응증류공정을 이용한 디메틸 에테르 생산" 한국화학공학회 42 (42): 44-52, 2004
• 13 Young Don Yoo, "Synthesis of dimethyl ether from syngas obtained by coal gas" 한국화학공학회 24 (24): 350-353, 2007
• 14 "DME handbook" Ohmsha 2006
• 15 ASPEN Tech, "ASPEN plus 2006 Manual"
• 16 Y. Ohno, "12th ICCS-November 2003 Coal Conversion into DME" 2003