METHOD AND DEVICE FOR THE SEPARATION OF ACIDIC GASES FROM A GAS MIXTURE

摘要

In a method for the separation of acidic gases from a gas mixture, the gas mixture is brought into contact with an absorption medium comprising water and at least one amine and having a separation temperature in the range from 0 to 130°C. Acidic gases are desorbed from the loaded absorption medium by means of stripping with water vapour in a desorption column, wherein the desorption is executed at a temperature at which a separation into a watery liquid phase and a low-water liquid phase takes place in the desorption column. The resulting watery phase and low-water liquid phase are separated from each other, the watery liquid phase is advanced to an evaporator in which water vapour is generated which is used to strip the acidic gases and the low-water liquid phase and watery phase are returned to the absorber as an absorption medium. A device for this method comprises an absorber (1), a desorption column (2) with a material exchange zone (3) that has a liquid drain (4), an evaporator (5) and a phase separation device (6) with an inlet point (7) and outlet points (8, 9) for the liquid phases, wherein the evaporator (5) is arranged separated from the phase separation device (6), the liquid drain (4) of the material exchange zone (3) is connected to the inlet point (7) of the phase separation device and the device has connecting lines (10, 11) from the outlet point (8) for watery liquid phase to the evaporator (5) and from the outlet point (9) for low-water liquid phase to the absorber (1).