Separation of gaseous components from a gaseous mixture by physical scrubbing

Claim 1

In a process for separating and obtaining as product gases at least two gaseous components from a gaseous mixture containing same comprising the following steps: (a) scrubbing said gaseous mixture with a physical scrubbing liquid exhibiting a higher dissolving power for at least one of the components to be separated than for at least one other of these components; (b) withdrawing a first scrubbing liquid stream, loaded with all of the components to be separated; (c) withdrawing a second scrubbing liquid stream, merely containing substantially only proportions of the less soluble component or components; (d) expanding said first scrubbing liquid stream of step (b) to liberate a gaseous fraction and reduced pressure first scrubbing liquid stream; (e) expanding said second scrubbing liquid stream of step (c) to obtain reduced pressure second scrubbing liquid stream and a gaseous stream containing less soluble component or components; (f) scrubbing the gaseous fraction of step (d) with the reduced pressure second scrubbing liquid stream of step (e) to remove from said gaseous fraction the more soluble component or components and withdrawing resultant gaseous fraction as a first product stream; and (g) subjecting combined reduced pressure scrubbing liquid streams to a separation of a gas comprising the more soluble components as well as of residual proportions of the less soluble components and withdrawing said gas as a second product gas, the improvement which comprises: (h) prior to the separation of step (g), further expanding the combined reduced pressure scrubbing liquid streams to obtain a gaseous fraction and a liquid fraction, and separating said gaseous fraction from said liquid fraction; (i) recompressing the liberated gaseous fraction of step (h); (j) scrubbing the recompressed gaseous fraction of step (i) with the reduced pressure second scrubbing liquid stream of step (e); and wherein the raw gas contains carbon dioxide as the less soluble component and hydrogen sulfide and/or carbonyl sulfide as the more soluble components.