METHOD AND APPARATUS FOR PRODUCING CARBON MONOXIDE BY CRYOGENIC DISTILLATION

摘要

In a method for producing carbon monoxide by cryogenic distillation using a system of distillation columns supplied with a mixture containing at least hydrogen, carbon monoxide and, at least some of the time, nitrogen, the mixture to be separated is cooled to a distillation temperature, hydrogen is removed from the mixture, a fluid containing at least carbon monoxide and at least part of the time nitrogen is separated in a denitrogenation column (11) to give a nitrogen-rich gas and a carbon monoxide-rich liquid, and a carbon monoxide-rich gas is extracted from the column system. When the nitrogen content of the fluid containing at least carbon monoxide and at least part of the time nitrogen falls below a predetermined threshold, a carbon monoxide-rich flow (17) is extracted from the denitrogenation column, and the column pressure is varied by controlling said carbon monoxide-rich flow.