METHOD FOR DISPOSAL OF ACID GASES CONTAINING HYDROGEN SULPHIDE AND AMMONIA ACCORDING TO CLAUS METHOD BELOW DEW POINT Russian patent published in 2017 - IPC C01B17/04 B01D53/48 

FIELD: oil and gas industry.

SUBSTANCE: initial acid gas is substoichiometrically burnt in Claus furnace, the produced heat is disposed in the waste-heat boiler with subsequent separation of liquid sulphur in a condenser, and the process gas leaving the thermal stage is fed to catalytic stage, where it is heated and passed through at least two successively installed Claus reactors with built-in heat exchangers for removal of Claus reaction heat, between the elements of which the alumina catalyst is filled. Reactors operate cyclically with periodic sequence switching. One of Claus reactors operates at a temperature above sulphur dew point and the other one operates at a temperature below the dew point. The process is carried out with the use of combined catalytic reactor installed at the inlet to the catalytic stage and including a preheating zone and a catalytic zone, where hydrolysis of COS and CS₂ occurs at a temperature 300-350°C, and operating alternately in a pair with each of Claus reactors in a mode above the sulphur dew point. The combined catalytic reactor is equipped with titanium oxide catalyst. Temperature gradient in the direction of the first Claus reactor is maintained 300-250°C above the dew point, and in the second one in the direction of Claus reactor the temperature gradient is 155-115°C. At the inlet, the temperature is maintained at least by 5°C above sulphur dew point, at the outlet it is below sulphur dew point. The catalytic Claus reactor is filled with alumina catalyst of different porosity. In the upper part of the alumina catalyst bed, the volume ratio of micropores and mesopores to the volume of ultra-macropores does not exceed 5, and in the lower one it is more than 10.

EFFECT: increased efficiency of sulphur condensation, increased degree of sulphur extraction.

8 cl, 1 tbl, 1 dwg