Patent ID: 8460431
Filing Date: 2013-06-11
Classification: B01D

Abstract:
1. A method of regenerating an amine-containing scrubbing solution obtained during gas purification and having CO 2 and sulfur compounds chemically bound therein, the method which comprises: a) heating a contaminated scrubbing solution to a temperature of at least 110° C. and compressing to a pressure of at least 4 bar, subsequently expanding the scrubbing solution in a first expansion stage, and removing a major proportion of CO b) heating the partially regenerated scrubbing solution obtained in step a) to a temperature of at least 130° C. and compressing to a pressure of at least 4 bar, and expanding the partially regenerated scrubbing solution in a second expansion stage to a pressure that is at least 0.5 bar higher than an expansion pressure of the first expansion stage, and removing a major proportion of the CO c) cooling the scrubbing solution removed in the second expansion stage to a temperature below 70° C. and expanding to standard pressure in a third expansion stage, and removing residual amounts of soluble CO d) removing condensed water from the gas mixture (vapors) cooled to standard temperature, and mixing the condensed water at a dosed amount with the completely purified scrubbing solution; and e) dividing the scrubbing solution removed after the first expansion stage or the second expansion stage into first and second partial streams, and returning the first partial stream in the circuit to the respective expansion stage and adjusting a temperature and a pressure thereof to conditions of the associated expansion stage, wherein residual amounts of sulfur compounds still present are removed from the first partial stream during the expansion and the second partial stream is further processed in accordance with step b) or step c).