Methane from synthesis gas and operation of high-temperature methanation

The methanation process is an important unit in generating substitute natural gas (SNG) from coal and in providing heat in the Long-Distance Nuclear Energy Transport (NFE) system. Procedures for methanizing synthesis gases containing CO, CO₂ and H₂ have been developed and tested at the Kernforschungsanlage Jülich GmbH (KFA - Federal Republic of Germany) since 1976. This is being carried out together with the partner in the NFE Project, Rheinische Braunkohlenwerke AG, Cologne (FRG).It has been demonstrated in several thousand operating hours at the KFA since 1979 that the procedures and components developed, as well as the catalysts employed satisfy the demands made by high-temperature methanation in the three-stage methanation plants ADAM I and ADAM II with a SNG gas production of 200 or 3300 m³ (STP)h⁻¹ and a useful heat capacity of 300 kJ/s or 5.8 MJ/s.In 1981 a single-stage pilot plant was put into operation at the KFA in which one reactor with cooled stepped reaction tubes and catalytic fixed beds was utilized. The test operation of 1100 hours shows that at a high gas load on the reaction tubes, thermodynamic equilibrium with a high methane content in the product gas can be achieved with simultaneous steam production at 100 bar.