Pneumatic conveying systems are normally divided into two types depending on if the solids-air ratio is high (dense phase) or low (dilute phase).
The dense phase pneumatic conveying system employs high air pressure and low air volume as the motive force to convey powder or granular bulk solid materials through a pipeline at low velocity. They are designed for high-capacity conveying rates and long distances. There are no moving parts besides the inlet and vent valves, so less wear occurs.
The dilute phase pneumatic conveying system allows the transportation of powders and bulk materials at a high throughput rate and over significant distances (not fragile materials). The dilute phase pneumatic conveying system utilizes rotary airlocks (rotary valves) that allow for the injection of calibrated dosages of material into the pipeline.
A booster delivers air under pressure (with control) at a high rate (24 to 30 m./s) via a valve in the conveying pipe.
