Due to the worldwide effort on developing renewable fuels, methane production by different methods has gained considerable interest. Considering the difficulties in producing methane from renewable sources such as biomass or black liquor, an interesting methanation reaction for increasing methane concentration in produced gas, found to be hydrogenation of carbon dioxide and is called Sabatier reaction.The present research is on simulation and optimization of the Sabatier reaction in a catalytic bed of Ruthenium on Alumina base. The simulation is based on two different scenarios: first, an adiabatic reactor with interstage cooling and second; an isothermal tube reactor with wall coolingIn this highly exothermic reaction, most of the produced heat must be removed by external cooling in order to prevent too high increase of the bed temperature. Regarding the design optimization done in the project, the best results occur for the isothermal case in 600K and 10 bar, while for the adiabatic run an interstage cooling strategy with 5 coolers and 6 reactors has been modeled. Additionally, recycling some part of cooled product to the entrance can increase the efficiency and reduce the number of reactors for the adiabatic strategy.The conclusion to this study shows that isothermal operation with external cooling is more favorable for lab-scale studies while adiabatic interstage design with recirculation of product gas would be more feasible in full scale cases.
Key words: methanation reactor, Ruthenium catalyst, isothermal, adiabatic