A method of separating acid components from an acid gas mixture using an absorbent, the method including the steps of: (a) passing the gas mixture through the absorbent in an absorber column such that acid component from the gas mixture is absorbed by the absorbent to form an acid-depleted fluid and an acid-rich absorbent stream, wherein the absorption step is carried out at 30-70 Bar, (b) drawing an acid-gas absorbent draw/return stream (21, 23) from the absorber column to a first heat exchange system, cooling the draw/return stream (21, 23) in the heat exchange system and returning the draw/return stream (22, 24) to the absorber column, (c) flash cooling the acid-rich absorbent stream by lowering pressure in the stream before passing the cooled acid-rich absorbent stream to the first heat exchange system, exchanging heat between the cooled acid-rich absorbent stream and warm streams (21, 23, 32, 41) and passing the warmed acid-rich absorbent stream to a first regeneration unit comprising separation drum; (d) separating an acid component from the acid-rich absorbent stream in the separation drum to form regenerated absorbent and an acid-rich vapour, (e) recycling the regenerated absorbent to the absorber column A1 via the first heat exchanger E1; (f) compressing at least part of the acid-rich vapour generated in the separation apparatus using a first compressor to form a first compressed acid-rich vapour, passing the compressed acid-rich vapour to the first heat exchange system and passing the resulting cooled compressed acid gas stream to a further separation apparatus where a CO2 gas stream is obtained and further absorbent is recovered as a stream which is combined with the cooled acid-rich absorbent stream upstream of the first heat exchange system, (g) wherein the method effects the exchange of heat in the first heat exchange system between at least a part of each of the following streams: i) the acid-rich absorbent stream (11/12) ii) the compressed acid-rich vapour iii) the regenerated absorbent iv) the draw/return stream (21, 22, 23, 24) taken from the absorber column; wherein streams ii), iii) and iv) are the warm streams of step c) and wherein the first heat exchange system is a single multichannel heat exchanger and the method is autothermal. (a) passing the gas mixture through the absorbent in an absorber column such that acid component from the gas mixture is absorbed by the absorbent to form an acid-depleted fluid and an acid-rich absorbent stream, wherein the absorption step is carried out at 30-70 Bar, (b) drawing an acid-gas absorbent draw/return stream (21, 23) from the absorber column to a first heat exchange system, cooling the draw/return stream (21, 23) in the heat exchange system and returning the draw/return stream (22, 24) to the absorber column, (c) flash cooling the acid-rich absorbent stream by lowering pressure in the stream before passing the cooled acid-rich absorbent stream to the first heat exchange system, exchanging heat between the cooled acid-rich absorbent stream and warm streams (21, 23, 32, 41) and passing the warmed acid-rich absorbent stream to a first regeneration unit comprising separation drum; (d) separating an acid component from the acid-rich absorbent stream in the separation drum to form regenerated absorbent and an acid-rich vapour, (e) recycling the regenerated absorbent to the absorber column A1 via the first heat exchanger E1; (f) compressing at least part of the acid-rich vapour generated in the separation apparatus using a first compressor to form a first compressed acid-rich vapour, passing the compressed acid-rich vapour to the first heat exchange system and passing the resulting cooled compressed acid gas stream to a further separation apparatus where a CO2 gas stream is obtained and further absorbent is recovered as a stream which is combined with the cooled acid-rich absorbent stream upstream of the first heat exchange system, (g) wherein the method effects the exchange of heat in the first heat exchange system between at least a part of each of the following streams: i) the acid-rich absorbent stream (11/12) ii) the compressed acid-rich vapour iii) the regenerated absorbent iv) the draw/return stream (21, 22, 23, 24) taken from the absorber column; wherein streams ii), iii) and iv) are the warm streams of step c) and wherein the first heat exchange system is a single multichannel heat exchanger and the method is autothermal. i) the acid-rich absorbent stream (11/12) ii) the compressed acid-rich vapour iii) the regenerated absorbent iv) the draw/return stream (21, 22, 23, 24) taken from the absorber column; wherein streams ii), iii) and iv) are the warm streams of step c) and wherein the first heat exchange system is a single multichannel heat exchanger and the method is autothermal.