Drying and calcining device capable of saving energy and increasing concentration of sulfuric acid SO made from gypsum

The utility model discloses a drying and calcining device capable of saving energy and increasing the concentration of sulfuric acid SO made from gypsum. The drying and calcining device comprises drying dewatering equipment, a cyclone dust collector and a sintering system; the sintering system comprises a preheater system, a rotary kiln and a clinker cooler which are sequentially connected with one another; the preheating system comprises three to five stages of cyclone barrels; an air inlet of the cyclone dust collector is connected with an air outlet of the drying dewatering equipment, a discharge outlet of the cyclone dust collector is connected with air inlet pipes of all the cyclone barrels, and a gas outlet of the cyclone dust collector is connected with a drying waste air outlet pipe; the first-stage cyclone barrel is provided with an acid making flue gas outlet; the last-stage cyclone barrel is connected with the rotary kiln. The drying and calcining device has the advantages that a gypsum drying dewa