METHOD FOR SEPARATION OF ACID GAS INTO COMPONENTS: HYDROGEN SULFIDE AND CARBON DIOXIDE Russian patent published in 2021 - IPC B01D53/14 C10L3/10 B01D53/52 B01D53/62 

FIELD: petrochemical industry.

SUBSTANCE: invention relates to the gas processing, oil refining and petrochemical industries. The invention deals with a method for separating acid gas into components: hydrogen sulfide and carbon dioxide. This method includes two successive stages of absorption and one stage of desorption of the absorbate, which provides for a circuit of circulation of the absorbent from the desorber to the absorber. The acid gas is separated, having a concentration of the initial components: 50% of the volume is hydrogen sulfide and 50% carbon dioxide: acid gas with a temperature not exceeding 45°C and an aqueous solution of methyldiethanolamine and diethylene glycol are fed into the absorber at the following ratio of components: methyldiethanolamine 60% by weight, diethylene glycol 15 % by weight, and water being the rest, at a temperature of 20°C, pressure of 450 kPa, the ratio of the absorber to the raw material is 4.5:1. In the downward movement of acid gas, at the first stage of absorption, hydrogen sulfide is absorbed to a value no lower than 70 % of the initial concentration, and at the second stage, a stream of carbon dioxide is released from the top of the absorber with a concentration of hydrogen sulfide no higher than 1 ppm, and hydrogen sulfide with a concentration of no less than 99% is released from the top of the desorber.

EFFECT: production of two high-purity technological streams: an acid gas concentrate with hydrogen sulfide content of at least 99.0% of the volume and a carbon dioxide stream with a concentration of at least 99.0 % of the volume.

1 cl