Absorption device for carbon dioxide in flue gas, flue gas purification device and control method of flue gas purification device

The invention provides an absorption device for carbon dioxide in flue gas, a flue gas purification device and a control method thereof.The absorption device for the carbon dioxide in the flue gas comprises an absorption tower, the absorption tower is internally provided with an installation space, an inlet and an outlet, and the inlet and the outlet are communicated with the installation space; the mounting space comprises a pre-washing section, an absorption section, a cooling section, a spraying section and a filling section, and an organic amine solution is arranged in the absorption section; wherein the inlet is communicated with the pre-washing section, the absorption section is arranged above the pre-washing section, the cooling section is arranged above the absorption section, the spraying section is arranged above the cooling section, the packing section is arranged above the spraying section and communicated with the outlet, and flue gas flows in the direction from the pre-washing section to the pac