These solids are evacuated based on a current of air with a determined speed, and in the specific direction to where we want to transport them, by calculating the pressure, volume of air and the distance we need to cover, taking into account the nature of the product to be transported.

Normally, it is divided into two chambers, in which the material circulates in one chamber and the air from a fan circulates in the other, separated from each other by a textile canvas of porous material (polyester or meta-aramid). The ascending air flow crosses the canvas and fluidises the material above it, keeping the particles suspended and acquiring properties similar to those of a liquid, making it flow easily. They are used in industries such as cement, steel mills, lime factories, gypsum, aluminium, thermal plants, etc.