Exhaust gas treatment system

An exhaust gas treatment system provided on a downstream side of a boiler which combusts fuel to heat water and generate water vapor, comprising:

• a CO2 recovery unit including:
• a CO2 absorption column for bringing gas containing CO2 generated in the boiler into contact with a CO2 absorbing solution so that the CO2 absorbing solution absorbs the CO2 and thereby the CO2 is removed out of the gas;
• an absorbing solution regeneration column for separating the CO2 from the CO2 absorbing solution which absorbed the CO2 to regenerate the CO2 absorbing solution;
• a condensate supply pipeline for supplying condensate, which contains the CO2 absorbing solution discharged from the CO2 absorption column, to a bottom portion of the absorbing solution regeneration column;
• and
• a CO2 separation section placed on a gas downstream side of the absorbing solution regeneration column for performing heat exchange, via a first heat exchanger, between the condensate which circulates in the condensate supply pipeline and a mixture of water vapor and CO2 discharged from the absorbing solution regeneration column so that the CO2 and the water vapor are cooled and separated;
• and
• an exhaust gas heat exchanger provided on a gas upstream side of the CO2 recovery unit for performing heat exchange between the gas before flowing into the CO2 recovery unit and the condensate so that the condensate is heated while the gas is cooled.