Modeling, optimization and operability analysis of Lurgi and Haldor Topsøe methanol synthesis reactors

Abstract

Abstract In this research is focused on modeling, simulation and operability analysis of methanol synthesis reactors in the Lurgi and Haldor Topsøe methanol plants at steady state condition. In this regard, the tubular methanol synthesis reactors are mathematically modeled based on the laws of conservation of mass and energy considering interparticle resistance inside the commercial CuO–ZnO/Al2O3 catalyst. Then, the methanol productivity, carbon conversion, and thermal performance of both configurations are compared at the same weight hourly space velocity. The mole fraction of methanol in the outlet stream from Lurgi and Topsøe designed reactors are 9.08 and 9.71, respectively. In addition, the hotspot temperature in the Lurgi and Topsøe reactors are 278.8 and 267.7 °C based on the considered model, respectively. The carbon dioxide and carbon monoxide conversion in the Topsøe designed reactor are 8.95 and 4.89 % higher compared to the Lurgi reactor. Finally, a multi-objective optimization problem is programmed considering methanol production rate, carbon dioxide conversion and catalyst loading as objective functions and the optimal operating conditions and specifications of Topsøe reactor are obtained considering two different strategies. The simulation results show that applying the optimal conditions on the Topsøe designed reactor enhance the methanol productivity up to 16.04 %.