FIELD: chemistry.
SUBSTANCE: nitrogen is removed from the cryogenic hydrocarbon composition. The cryogenic hydrocarbon composition is divided into a first portion and a second portion having the same composition and phase as the first portion. The first part is fed to a desorption column of nitrogen operating at a desorption pressure, from which a nitrogen-depleted liquid is discharged. The second portion is fed to a nitrogen-depleted liquid or to a liquid hydrocarbon product stream or process steam that is produced from nitrogen-depleted liquid by performing at least a pressure-depletion stage of the nitrogen-depleted liquid to a flash point that is lower than the desorption pressure. The second portion bypasses the nitrogen desorption column between the flow division and the supply of the second portion to the nitrogen-depleted liquid, or the liquid hydrocarbon product stream, or process steam.
EFFECT: reducing the size of the installation and increasing the reliability.
20 cl, 2 dwg
