Flue gas treatment system and method

A flue gas treatment system comprising:

• a desulfurization apparatus which removes sulfur oxides in flue gas from a boiler, which is configured to generate SO3 mist from a portion of SO3 gas in the flue gas;
• a mist collection and agglomeration apparatus which is provided on a gas flow downstream side of the desulfurization apparatus and introduces the flue gas from the desulfurization apparatus, which is configured to form agglomerated SO3 mist by causing particles of the SO3 mist contained in the flue gas to be bonded together and have particle sizes bloat;
• wherein the mist collection and agglomeration apparatus is configured to re-scatter the agglomerated SO3 mist therefrom in a case a flow velocity of the flue gas exceeds a critical filtration wind velocity for mist collection;
• a flue gas cooling tower which is provided on the gas flow downstream side of the mist collection and agglomeration apparatus and introduces the flue gas from the mist collection and agglomeration apparatus and cools the flue gas, which is configured to form dilute sulfuric acid mist from the agglomerated SO3 mist contained in the flue gas by absorbing water vapor;
• and
• a CO2 recovery apparatus which is provided on the gas flow downstream side of the flue gas cooling tower, comprising:
• a CO2 absorption tower including a CO2 absorption unit which introduces the flue gas from the flue gas cooling tower and removes CO2 contained in the flue gas by being brought into contact with a CO2 absorbent and a washing unit which is provided on the gas flow downstream side of the CO2 absorption unit and washes the flue gas, which are configured to form CO2 absorbent bloated mist from the dilute sulfuric acid mist contained in the flue gas by absorbing water vapor and CO2 absorbent vapor, and a mist collection unit which is provided on a gas flow downstream side of the washing unit and is configured to collects the CO2 absorbent bloated mist;
• and
• an absorbent regeneration tower which introduces the CO2 absorbent having absorbed CO2 in the CO2 absorption tower therefrom and recovers CO2 from the CO2 absorbent by releasing CO2 therefrom to regenerate the CO2 absorbent.