Multi-rotor vertical grading device

The utility model discloses a multi-rotor vertical type grading device which comprises a barrel body which comprises a main barrel body, a conical barrel body, a bulk material barrel body and a material receiving conical barrel body which are sequentially arranged from top to bottom; the impeller rotors are horizontally arranged in the circumferential direction of the main cylinder at intervals; the discharging pipe is arranged at the top of the main barrel; the first air stabilizing cone cylinder is arranged in the bulk material cylinder, the large end of the first air stabilizing cone cylinder faces upwards and is connected with the upper portion of the bulk material cylinder, and the lower end of the first air stabilizing cone cylinder is suspended; the multiple secondary air inlet pipes are horizontally arranged at intervals in the circumferential direction of the bulk material barrel, and the secondary air inlet pipes communicate with the bulk material barrel in the tangential direction; the feeding pipe