Patent ID: 7927568

Claim:
A method of capturing CO 2 from flue gas emanating from a carbonaceous fuel combusting power plant, which includes a source of oxygen and a combustion chamber for combusting the carbonaceous fuel with oxygen and thereby producing flue gas comprising CO 2 , water and excess oxygen as its main components, the method comprising the steps of: (a) conducting at least a first portion of the flue gas to a first flue gas channel; (b) compressing the first portion of the flue gas for producing a compressed flue gas stream at a pressure less than about one hundred bar; (c) cooling the compressed flue gas stream in a primary CO 2 separating unit to a temperature of at least 10° C., for capturing a first portion of the CO 2 by condensing the first portion to produce a first liquid CO 2 stream and a high pressure vent gas stream comprising oxygen and excess CO 2 ; (d) discharging the first liquid CO 2 stream from the power plant; and (e) conducting the high pressure vent gas stream to a secondary CO 2 separating unit for capturing a second portion of the CO 2 by adsorbing it to an adsorbing material.