Absorber column for production of a clean synthesis gas by at least partial separation of carbon dioxide and sulfur compounds, especially hydrogen sulfide, from a crude synthesis gas comprising hydrogen, carbon oxides and sulfur compounds, by absorbing with an absorbent, wherein the absorber column comprises the following constituents and assemblies: - a shell which - based on a state of the absorber column arranged as intended - extends along a longitudinal axis that runs parallel to the vertical and encloses an inner space, wherein the inner space comprises an upper absorption region and a lower absorption region, each of which contains at least one mass transfer zone, wherein the mass transfer zones of the upper absorption region serve predominantly for removal of carbon dioxide and wherein the mass transfer zones of the lower absorption region serve predominantly for removal of sulfur compounds, - an inlet disposed below the lowermost mass transfer zone of the lower absorption region for the crude synthesis gas, - an outlet disposed at the top end of the shell for the clean synthesis gas, - an outlet disposed at the lower end of the upper absorption region for a first fraction of the laden absorbent laden with carbon dioxide, - a first regeneration apparatus for the regeneration of the first fraction of the laden absorbent by expansion (flash regeneration), - an outlet disposed at the bottom end of the shell for a second fraction of the laden absorbent laden with sulfur compounds, - a second regeneration apparatus for the regeneration of the second fraction of the laden absorbent by heating (hot regeneration), - a first absorbent inlet disposed above the uppermost mass transfer zone of the upper absorption region for the absorbent regenerated by heating, which is in fluid connection with the second regeneration apparatus via a first feed conduit, - a second absorbent inlet disposed below the first absorbent inlet and within the upper absorption region for the absorbent regenerated by expansion, which is in fluid connection with the first regeneration apparatus via a second feed conduit, - a connecting conduit between the first feed conduit and the second feed conduit, where the connecting conduit is configured such that a defined proportion of the absorbent regenerated by expansion can be fed into the absorbent regenerated by heating before it is introduced into the absorber column. - a shell which - based on a state of the absorber column arranged as intended - extends along a longitudinal axis that runs parallel to the vertical and encloses an inner space, wherein the inner space comprises an upper absorption region and a lower absorption region, each of which contains at least one mass transfer zone, wherein the mass transfer zones of the upper absorption region serve predominantly for removal of carbon dioxide and wherein the mass transfer zones of the lower absorption region serve predominantly for removal of sulfur compounds, - an inlet disposed below the lowermost mass transfer zone of the lower absorption region for the crude synthesis gas, - an outlet disposed at the top end of the shell for the clean synthesis gas, - an outlet disposed at the lower end of the upper absorption region for a first fraction of the laden absorbent laden with carbon dioxide, - a first regeneration apparatus for the regeneration of the first fraction of the laden absorbent by expansion (flash regeneration), - an outlet disposed at the bottom end of the shell for a second fraction of the laden absorbent laden with sulfur compounds, - a second regeneration apparatus for the regeneration of the second fraction of the laden absorbent by heating (hot regeneration), - a first absorbent inlet disposed above the uppermost mass transfer zone of the upper absorption region for the absorbent regenerated by heating, which is in fluid connection with the second regeneration apparatus via a first feed conduit, - a second absorbent inlet disposed below the first absorbent inlet and within the upper absorption region for the absorbent regenerated by expansion, which is in fluid connection with the first regeneration apparatus via a second feed conduit, - a connecting conduit between the first feed conduit and the second feed conduit, where the connecting conduit is configured such that a defined proportion of the absorbent regenerated by expansion can be fed into the absorbent regenerated by heating before it is introduced into the absorber column.