The pneumatic conveying system is composed of an air source device, a sending device, a material and gas separation device, a dust removal device and a control system. The working principle is that the material to be transported is sent out by the sending device, flows through the pipeline to the end of the material gas separation device, the material is separated into the storage bin, and the gas is discharged into the atmosphere after dust removal. According to the pressure formation mode in the system, the pneumatic conveying system of the pipeline can be divided into two types: negative pressure conveying and positive pressure conveying, also called "suction conveying" and "pressure conveying". And because the object in the air mixed with solid particles is a "2-phase flow", according to the "ratio of material to gas" (the ratio of material weight to gas weight) of the solid-gas 2 phase flow, it is divided into "dense phase" and "dilute phase".

The following processes relate to positive pressure dense phase pipeline pneumatic conveying systems:

Feed stage

Open the feed valve, and the material falls into the conveyor freely. When the rising material in the conveyor touches the level meter, the level meter will send a full signal, and the feed valve will automatically close. At the same time, a time monitoring program is also set up in the control system to ensure that the feed can be successfully completed after the level meter fails or there is no ash in the ash hopper for a long time.

Fluidizing pressure phase

The pneumatic intake valve automatically opens, the compressed air enters from the gasification chamber at the bottom of the conveyor, diffuses through the fluidized bed, and at the same time, the air pressure in the conveyor gradually rises.

Transport stage

When the pressure in the conveyor reaches a certain value, the weighing module sends a signal, the discharge valve automatically opens, the material flow on the fluidized bed is strengthened, the conveying begins, and the material in the conveyor is gradually reduced. The material in this process is always in the fluidized and input-ash pipeline.

Purge stage

When the conveying of materials in the conveyor is completed, the pressure drops to the resistance of the pipeline, the indicator light sends a signal, the ventilation continues for a certain time, the compressed air cleans the pipeline, and then the intake valve is closed, and the discharge valve is closed at a certain interval to complete a conveying cycle, so as to enter the next working cycle.