FIELD: oil and gas industry.
SUBSTANCE: invention relates to a method for removing acid gases, especially carbon dioxide and hydrogen sulphide, from a hydrocarbon-rich fraction, especially natural gas. In the disclosed method, hydrocarbon-rich fraction (1) is cooled and partially condensed (E1-E4), and resulting carbon dioxide-enriched liquid fraction (5), by rectification (T1), is separated into carbon dioxide-rich liquid fraction (7) and deoxygenated gas fraction (6). Hydrocarbon-rich fraction (1) is cooled (E1-E4) to a temperature close to the carbon triple point (-56.6 °C) using a closed multistage refrigeration cycle, the carbon dioxide fraction in the refrigerant of which is more than 99.5 %. Rectification column operates at a pressure of 40 to 65 bar. Heating of reboiler (E5) of rectification column (T1) is carried out by means of a condensing refrigerant substream of cycle (28), the pressure of which is at a suitable level for this purpose.
EFFECT: higher yield of carbon dioxide from the gas mixture and lower energy consumption.
10 cl, 2 dwg
