Issue
Korean Journal of Chemical Engineering,
Vol.38, No.10, 2020-2033, 2021
Investigation of anti-condensation strategies in the methanol synthesis reactor using computational fluid dynamics
Flow mal-distribution in the shell side of the gas-cooled conventional reactor (CR) in the mega methanol plant is responsible for producing gas condensate in the catalytic zone. This phenomenon leads to catalyst agglomeration and efficiency reduction in the reactor. In this study, two novel and viable strategies, possible to be implemented in working reactors, are introduced to prevent condensation. In the first strategy, co-current mode (CCM), the reactant flow changes from counter-current into the co-current. In this regard, the feed inlet is replaced from the bottom of the reactor into the top. In the second strategy, changed-bed mode (CBM), the catalyst particles at the last two meters of the reactor are replaced with non-reactive ceramic balls. The results for three-dimensional computational fluid dynamics (CFD) in CR have been validated against previous study and industrial data, indicating close agreement. The main advantage of CCM and CBM is that the sudden temperature drop fails to occur at the end of the reactor. Consequently, the higher temperature of the products prevents water and methanol condensation. In addition, the CCM leads to a milder temperature profile throughout the shell side, which increases catalyst durability.
[References]
  1. Leonzio G, J. CO2 Utilization, 27, 2326, 2018
  2. Chen L, Jiang QZ, Song ZZ, Posarac D, Chem. Eng. Technol., 34(5), 817, 2011
  3. Sadeghi S, Vafajoo L, Kazemeini M, Fattahi M, APCBEE Procedia, 10, 84, 2014
  4. Mirvakili A, Rahimpour M, Appl. Therm. Eng., 91, 1059, 2015
  5. Mirvakili A, Bakhtyari A, Rahimpour MR, Appl. Therm. Eng., 128, 64, 2018
  6. Samimi F, Karimipourfard D, Rahimpour MR, Chem. Eng. Res. Des., 140, 44, 2018
  7. Keshavarz A, Mirvakili A, Chahibakhsh S, Shariati A, Rahimpour M, Chem. Eng. Processing-Process Intensification, 158, 108176, 2020
  8. Nasrollahi F, Bakeri G, Ismail AF, Rahimnejad M, Imanian M, Korean J. Chem. Eng., 30(10), 1867, 2013
  9. Rahimpour MR, Lotfinejad A, Chem. Eng. Process., 47(9-10), 1819, 2008
  10. Eksiri Z, Mozdianfard MR, Mirvakili A, Rahimpour MR, Chem. Eng. Res. Des., 162, 212, 2020
  11. Luyben WL, Ind. Eng. Chem. Res., 49(13), 6150, 2010
  12. Rahmatmand B, Rahimpour MR, Keshavarz P, Fuel Process. Technol., 193, 159, 2019
  13. Mirvakili A, Chahibakhsh S, Ebrahimzadehsarvestani M, Soroush E, Rahimpour M, J. Taiwan Inst. Chem. Engineers, 104, 40, 2019
  14. Redondo B, et al., Chem. Eng. Processing-Process Intensification, 143, 107606 (2019).
  15. Manenti F, Leon-Garzona A, Bozzano GG, Chem. Eng. Trans, 35 (2013).
  16. Son M, Woo Y, Kwak G, Lee YJ, Park MJ, Int. J. Heat Mass Transfer, 145, 118776, 2019
  17. Pavlisic A, Hus M, Prasnikar A, Likozar B, J. Clean Prod., 275, 122958, 2020
  18. Hus M, Kopac D, Stefancic N, Jurkovic D, Likozar B, Catal. Sci. Technol., 7, 5900, 2017
  19. Kopac D, Hus M, Ogrizek M, Likozar B, J. Phys. Chem. C, 121, 17941, 2017
  20. Balduzzi F, Bianchini A, Maleci R, Ferrara G, Ferrari L, Renew. Energy, 85, 419, 2016
  21. Xia B, Sun DW, Computers and Electronics in Agriculture, 34, 5 (2002).
  22. Rahimpour MR, Chem. Eng. Commun., 194(10-12), 1638, 2007
  23. Kopetsch H, Process and plant for producing methanol, in, Lurgi GmbH (2011).
  24. Tijm PJA, Waller FJ, Brown DM, Appl. Catal. A: Gen., 221(1-2), 275, 2001
  25. Miieller D, Bormann A, Process and plant for producing methanol, in, LURGI GMBH (2011).
  26. Cui X, Kær SK, Chem. Eng. J., 393, 124632, 2020
  27. Marlin DS, Sarron E, Sigurbjornsson O, Front. Chem., 6, 446, 2018
  28. Zhang J, Liu T, Huang Q, Luo Z, Lu A, Zhu L, Mater. Chem. Phys., 255, 123611, 2020
  29. Lakhani S, Raul A, Saha SK, Appl. Therm. Eng., 123, 458, 2017
  30. Dubovsky V, Ziskind G, Letan R, Appl. Therm. Eng., 31, 3453, 2011
  31. Ansys AF, 15.0 User’s Guide, ANSYS, Inc., United States (2013).
  32. Fluent A, ANSYS fluent theory guide 15.0, ANSYS, Canonsburg, PA, 33 (2013).
  33. Yao ZQ, Shen HC, Gao H, J. Hydrodynamics, 25, 131, 2013
  34. Peter M, Fichtl MB, Ruland H, Kaluza S, Muhler M, Hinrichsen O, Chem. Eng. J., 203, 480, 2012
  35. Ferziger JH, Peric M, Computational methods for fluid dynamics, Springer (2002).