Multi-stage thermal cycle drying device

The utility model discloses a multistage heat circulation drying device which comprises a drying cylinder, an air heater is arranged at one end of the top of the drying cylinder, an air pipe is vertically connected to the air heater, the bottom of the air pipe is inserted into the drying cylinder, and a rotating shaft is rotatably inserted into the center of the top of the drying cylinder. A circulating lifting assembly is arranged on the external surface, located in the drying cylinder, of the rotating shaft, a multi-stage drying assembly is arranged on the peripheral surface, located in the drying cylinder, of the air pipe, and a circulating pipeline is arranged at the end, away from the hot-air blower, of the top of the drying cylinder and communicates with the interior of the drying cylinder; a hot gas recovery assembly is arranged at the bottom of the circulating pipeline, and a feeding port is formed in the top of the drying cylinder. The multi-stage drying assembly and the circulating lifting assembly