Process and plant for producing methanol from synthesis gases having a high proportion of carbon dioxide

摘要

The invention relates to a process for producing methanol and to a plant for producing methanol. A first fresh gas suitable for production of methanol and having a high carbon dioxide content is pre-compressed by a first compressor stage to obtain a second fresh gas. The second fresh gas is merged with a recycle gas stream and further compressed to synthesis pressure in a second compressor stage. Catalytic conversion of the thus obtained synthesis gas stream in a plurality of serially arranged reactor stages with intermediate condensation and separation of the crude methanol reduces the recycle gas amount in the synthesis circuit to such an extent that recycle gas may be directly recycled to the second fresh gas stream, thus ensuring that no recycle gas compressor stage is required and that the total compressor power may be reduced.