The invention discloses an industrial
flue gas purification, desulfurization and
denitrification integrated device and a working method thereof. A section of pretreatment
flue is additionally arranged on a
flue in front of an absorption
tower, and the outlet of the pretreatment flue is connected to the inlet flue of the absorption
tower in a downward gradient mode; an
ozone spraying device and a pre-spraying device are arranged in the pretreatment flue from the inlet in turn; and the
ozone spraying device is connected with an
ozone generator through a
gas transmission pipeline and converts SO2 into SO3
sulfide which is freely soluble in water, the pre-spraying device absorbs SO3 which is freely soluble in water and converts the SO3 into H2SO4, namely
sulfuric acid, and
flue gas is cooled simultaneously, so that the aim of removing
nitrogen oxide and
sulfur dioxide is fulfilled. The device can efficiently remove the
nitrogen oxide, has an obvious effect of removing particulate matters such as the
sulfur dioxide, dust and the like, and is desulfurization and
denitrification equipment with a wide application prospect.