Exhaust gas treatment device and exhaust gas treatment method

An exhaust gas treatment device comprising:

• a first exhaust gas flow path through which a first combustion exhaust gas discharged from a first power generation facility flows;
• a second exhaust gas flow path through which a second combustion exhaust gas discharged from a second power generation facility flows;
• a waste heat recovery unit provided to the first exhaust gas flow path and recovers waste heat of the first combustion exhaust gas;
• a nitrogen oxide removal unit configured to remove nitrogen oxide in an integrated combustion exhaust gas into which the first combustion exhaust gas and the second combustion exhaust gas are integrated, the first combustion exhaust gas flowing through the first exhaust gas flow path with the waste heat of the first combustion exhaust gas having been recovered by the waste heat recovery unit, and the second combustion exhaust gas flowing through the second exhaust gas flow path with a temperature of the second combustion exhaust gas being higher relative to the first combustion exhaust gas;
• an integrated waste heat recovery unit configured to recover waste heat of the integrated combustion exhaust gas with the nitrogen oxide having been removed by the nitrogen oxide removal unit;
• and
• a CO2 recovery unit that recovers CO2 in the integrated combustion exhaust gas by a CO2 absorbing liquid with the waste heat of the integrated combustion exhaust gas having been recovered by the integrated waste heat recovery unit.

A exhaust gas treatment method comprising the steps of:

• removing nitrogen oxide in an integrated combustion exhaust gas into which a first combustion exhaust gas and a second combustion exhaust gas are integrated, the first combustion exhaust gas being discharged from a power generation device with waste heat of the first combustion exhaust gas having been recovered by a waste heat recovery unit which is provided to a first exhaust gas flow path, and the second combustion exhaust gas flowing through a second exhaust gas flow path which is provided to be connected between a front stage and a downstream stage of the waste heat recovery unit on the first exhaust gas flow path with a temperature of the second combustion exhaust gas being higher relative to the first combustion exhaust gas from which the waste heat has been recovered by the waste heat recovery unit;
• recovering waste heat of the integrated combustion exhaust gas with the nitrogen oxide having been removed;
• and
• recovering CO2 in the integrated combustion exhaust gas by a CO2 absorbing liquid, the waste heat of the integrated combustion exhaust gas having been recovered.

An exhaust gas treatment method comprising the steps of:

• removing nitrogen oxide in an integrated combustion exhaust gas into which a first combustion exhaust gas and a second combustion exhaust gas are integrated, the first combustion exhaust gas being discharged from a first power generation device with waste heat of the first combustion exhaust gas having been recovered by a waste heat recovery unit which is provided to a first exhaust gas flow path, and the second combustion exhaust gas being discharged from a second power generation device and flowing through a second exhaust gas flow path with a temperature of the second combustion exhaust gas being higher relative to the first combustion exhaust gas from which the waste heat has been recovered by the waste heat recovery unit;
• removing nitrogen oxide in the integrated combustion exhaust gas into which combustion exhaust gases are integrated, the combustion exhaust gases being discharged and flowing through a plurality of exhaust gas flow paths at least one of which is provided with a waste heat recovery unit that recovers waste heat of the combustion exhaust gas;
• recovering waste heat of the integrated combustion exhaust gas with the nitrogen oxide having been removed;
• and
• recovering CO2 in the integrated combustion exhaust gas by a CO2 absorbing liquid, the waste heat of the integrated combustion exhaust gas having been recovered.