Dry flue gas desulphurization, denitrification and dust-removal integrated purification system

The present invention provides a dry flue gas desulphurization, denitrification and dust-removal integrated purification system. The system comprises a boiler at which a SNCR denitrification system is mounted, a dust-removal system, a flue, a pulverizer, a filtration system and a chimney; The boiler at which the SNCR denitrification system is mounted, the dust removal system, the filtration system and the chimney are orderly connected by the flue; a dry powder absorbent inlet is provided on the flue that is between the dust removal system and the filtration system; the dry powder absorbent inlet is connected to an outlet of the pulverizer through a pipeline; and an absorbent inlet is provided on the grinder. The purification system is a full-dry type desulphurization, denitrification and dust-removal integrated purification system, and does not consume water, thereby lowering the risk of equipment corrosion.