The pneumatic ash discharge system uses air as the conveying medium and power to transport ash from the rear part of the boiler to the air chamber, with the intermediate compartments made of fiber fabric material. Fluidizing air permeates uniformly into the ash layer through fiber fabric compartments from the bottom small chamber of the device, causing the ash to fluidize and flow along the slope of the trough. Fine ash from the heating surface, flue, dust collector, and other ash collection hoppers is conveyed to the storage facility at the process location through pipes or other sealed devices. The choice and layout of the conveying route are quite flexible, but due to the high conveying speed and large power consumption, the wear of the conveying pipeline is severe, especially on valves.