TWO-STAGE ADSORBING AND SEPARATING EQUIPMENT FOR RECOVERING CARBON DIOXIDE FROM WASTE COMBUSTION GAS AND TWO-STAGE METHOD FOR ADSORBING AND SEPARATING CARBON DIOXIDE

摘要

PROBLEM TO BE SOLVED: To prevent a decrease in the productivity of an adsorbing and separating device due to moisture contamination at the time of using synthetic zeolite as an adsorbent to produce carbon dioxide from a waste combustion gas having a high content of moisture by connecting a predehumidifier to the carbon dioxide adsorbing and separating device and enhancing the dehumidifying effect of a dehumidification tower. SOLUTION: The adsorbing and separating device is provided with a regenerating gas- heating heat exchanger 21, a sprinkling dust removal tower 29, two tower-type dehumidifiers 23a and 23b, three tower-type one-stage adsorbing and separating devices 24a to 24c and three tower-type two-stage adsorbing and separating devices 25a to 25c to recover the carbon dioxide of =95vol.% purity from the waste combustion gas of a steam supply and power generating plant, etc., contg. 8-15vol.% carbon dioxide. The waste gas from a cleaning stage is supplied to the adsorption tower having finished an adsorption stage among the one-stage adsorbing and separating devices 24a to 24c to recover carbon dioxide. Meanwhile, the whole amt. of the adsorbed waste gas of the two-stage adsorbing and separating devices 25a to 25c and the cleaned waste gas are heat-exchanged with the waste combustion gas to cool the waste combustion gas.