Efficient method and device for adsorption/desorption of carbon dioxide from gas streams

A method for separating gaseous carbon dioxide or gaseous carbon dioxide and water from a gas mixture,

• by cyclic adsorption/desorption using a sorbent material adsorbing said gaseous carbon dioxide,
• said method using at least one unit containing an adsorber structure with said sorbent material, the unit being
• openable to flow-through of said gas mixture and for contacting said gas mixture with the sorbent material for the adsorption step,
• evacuable to a vacuum pressure of 500 mbar (a) or less, and
• the adsorber structure located in said unit being heatable to a temperature of at least 50° C. for the desorption of at least said gaseous carbon dioxide or carbon dioxide and water vapour,
• wherein the method comprises the following sequential and in this sequence repeating steps:
• (a) contacting said gas mixture with said sorbent material to allow at least said gaseous carbon dioxide with or without water vapour to adsorb on the sorbent material under ambient atmospheric pressure conditions in the range of 0.8 to 1.2 bar (a) in an adsorption step;
• (b) at least one of:
• evacuating said unit to a pressure in the range of 20-400 mbar (a) and heating said sorbent material in said unit to a temperature in the range of 50-180° C. in a desorption step;
• and
• extracting at least the desorbed gaseous carbon dioxide and desorbed water vapour or desorbed gaseous carbon dioxide and water vapour originating from injected steam from the unit and separating gaseous carbon dioxide from water vapour by water condensation downstream of the unit;
• (c) actively cooling the adsorber structure with said sorbent material in said unit to a temperature larger or equal to ambient atmospheric temperature and re-pressurisation of the unit to ambient atmospheric pressure conditions;
• wherein
• (i) in step (c) at least parts of the heat released by the adsorber structure with said sorbent material in said unit during cooling is recovered and stored in a first heat storage device and used for other process steps in said unit or in at least one different but equivalent unit operated in essentially the same manner in parallel;
• and
• (ii) wherein during step (b) at least parts of at least one of the sensible and latent heat of gaseous carbon dioxide and water vapour extracted from the unit is recovered and stored in a second heat storage device and used for other process steps in said unit or in at least one different but equivalent unit operated in essentially the same manner in parallel;
• and
• (iii) wherein during step (b) at least parts of the heat required for heating said sorbent material in said unit is supplied from heat recovered in at least one of step actions (i) and (ii) of previous sequence(s) of said unit and/or of at least one different but equivalent unit operated in essentially the same manner in parallel;
• wherein at least one of (i) or (ii) is implemented, as well as (iii).