CO2 and H2O are two important by-products that affect DME production in the reactor. Besides, CO2 is an important air pollutant and may have an impact on global climate change. Therefore, this study tries to increase CO2 conversion along with DME production simultaneously and independently proposing a multi-stage reactor using a multi-objective approach. In this respect, a variety of effective optimization degrees of freedom such as H2O separation ratio, feed temperature, inter-stage cooling temperature, shell temperatures, number of reactors in series and reactor configurations (adiabatic/non-adiabatic fixed bed reactor; (non-)AFBR) at each stage are optimized to improve overall reactor efficiency. An industrial scale catalytic fixed bed reactor is used and the results of the proposed multi-objective multi-stage case are compared with a single-stage single-objective (base case) and single-stage multi-objective optimization one. The comparative test studies clearly demonstrate superiority of the proposed methodology to give optimal solutions with much less CO2 productivity and high DME productivity at the end of the staged reactor. Besides, the simulation results of multi-objective optimization introduced more optimum points as a Pareto front compared to the single objective optimization case.

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