An analysis of the efficiency of flue gases energy potential conversion through methanation

The purpose of the paper targets the development of a mathematic model that encompasses the phenomena of decarbonization through methanation processes, aided by the use of a nickel / alumina catalyst. Emphasis was placed on the impact pressure and temperature ranges have on the process. A nickel catalyst, type NKM – 4A was considered in a temperature range of 220-260 °C in order to highlight the influence of the pressure of CO2and H2reactants. The model used in numerical simulations is derived from the Langmuir - Hinshelwood mechanism, admitting dissociative adsorption of CO2 and O (atomic oxygen), after which methane is formed. The numerical simulations were validated experimentally, concluding in an optimal ratio of hydrogen pressureto carbon dioxide pressure in therangefrom 3 to 4, with further experimental data extending the range up to 5. The experimental base from the Maritime University of Constanța was also presented, a base equipped with a methane generator and a methaniser. The researches (in incipient phase) performed only the conversion of pure carbon dioxide with the ratio hydrogen to carbon dioxide equal to 4. They will be extended to the flue gases of an internal combustion engine driving an electric generator.