Ammonia desulfurization device for boiler flue gas and technological process thereof

The invention provides an ammonia desulfurization device for boiler flue gas and a technological process thereof. The device comprises an absorption tower, an ammonia water tank, a concentration and crystallization system, a crystal discharging system, a circulating absorption system and a water washing system, wherein the circulating absorption system comprises a first-stage circulating absorption system and a second-stage circulating absorption system. According to the invention, high-temperature flue gas of the boiler induced-draft fan enters the circulating absorption section after coolingby the concentration and crystallization system; an absorption liquid is sprayed, undergoes an absorption reaction with a SO2 component in the flue gas, then returns back to an oxidation tank and re-enters a spraying layer, so the circulation of the absorption reaction is realized; clean flue gas obtained after concentration and absorption enters a water washing section, mist droplets are removed, and then the clean flue