Patent attributes
An ammonia-based multi-zone double-loop process for ultra-low emission of multi-pollutant. From an absorption tower inlet, the flue gas successively passes through cooling concentration crystallization, sulfur oxide absorption, water washing and purifying and dust and mist removing zones, which are separated by gas permeable liquid collecting plates, forming clean flue gas and discharged from an outlet. The cooling concentration crystallization zone, the sulfur oxide absorption zone, and the water washing and purifying zone are respectively provided with a plurality of sprayers, and respectively use a concentration liquid, an absorption liquid, and a water washing liquid as spraying liquids. The absorption, concentration and water washing liquids, after converging respectively, into absorption, concentration crystallization and water washing circulation tanks, the absorption, concentration and water washing liquids, respectively, are sprayed in a circulating manner through absorption, concentration and water washing pumps.