Variable side cooling for acid gas removal

An absorber for use in an acid gas removal process, the absorber comprising:

• a side cooler configured to receive a side stream from the absorber and cool the side stream to produce a cooled side stream;
• a first return line configured to pass a first output stream from the side cooler back into the absorber at a tray below a draw point for the side stream, wherein the first output stream is configured to be routed back into the absorber to absorb acid gas from the feed gas within the absorber;
• and
• a second return line configured to pass a second output stream from the side cooler to a point below the first output stream, wherein the second output stream from the side cooler is configured to be routed directly to a bottom of the absorber, and wherein the second portion is configured to be routed back into the absorber so as to not absorb the acid gas from the feed gas within the absorber,
• wherein:
• the absorber is configured to receive a feed gas and counter-currently contact the feed gas with a lean solvent stream to remove acid gas from the feed gas,
• the absorber is configured to produce a treated feed gas stream from the absorber,
• the absorber is further configured to produce a rich solvent stream from the absorber, and
• the rich solvent stream comprises H2S and CO2 removed from the feed gas.