FIELD: oil-and-gas industry.
SUBSTANCE: method includes two stages of absorption: at the first stage selective stripping with reference to carbon dioxide with release of sour gas with the content of carbon dioxide no more than 30-40%, and the stripped gas with the content of hydrogen sulphide no more than 5-7 mg/m3, sent further to the second stage of absorption with obtaining the stripped gas with the content of carbon dioxide no more than 50-200 mg/m3 and total absence of hydrogen sulphide, and sour gas with the content of hydrogen sulphide no more than 200 mg/m3 is performed. Saturation of alkylamine absorbent at each stage of absorption by sour components doesn't exceed 0.4 mol/mol, and natural gas has a hydrogen sulphide to carbon dioxide ratio, equal to 1.0, but no more than 1.5, and hydrogen sulphide concentration from 3.5 to 8.0 by the volume %. The unit comprises two series units for absorption stripping of gas comprising an absorber, a regenerator, pumps, a refrigerator, a recuperative heat exchanger, a boiler, a vessel and pipings of units of absorption stripping of gas.
EFFECT: invention provides effective stripping of natural gas from carbon dioxide and hydrogen sulphide.
19 cl, 2 dwg, 3 ex, 1 tbl
