Grain circulating drying system and grain drying machine comprising same

The invention discloses a grain circulating drying system and a grain drying machine comprising the grain circulating drying system, and the grain circulating drying system comprises a grain feeding part for guiding grains to enter, a drying part for drying the grains, and a grain discharging part for guiding the grains to be discharged, the hoister is used for driving the grains to be circularly dried; the air heater is used for providing a heat source; and the controller is used for controlling the whole grain circular drying system. The grain drying machine comprises the grain circulating drying system. According to the grain drying device, dried grains are input into the grain feeding part again through the elevator to be circularly dried, so that the grains are dynamically dried in the falling process of the drying part, and non-uniform drying caused by local heating of the grains during standing drying is avoided; and hot air is uniformly output through a plurality of transversely-arranged separation pi