A pneumatic waste collection system consists of a series of drop boxes connected to a suction point via underground pipes.

The collection cycle starts when segregated refuse is dropped into the boxes, which may be located inside houses, in common areas in apartment blocks, or in public areas outdoors. The refuse falls due to gravity to the valves installed at lower levels and stored there temporarily.

• Static system. Every so often the refuse stored is emptied out. A central computer coordinates collection. First a depression is created in the pipe network and an air current enters that enables the refuse to be sucked along to a central point. The refuse is conveyed at speeds between 60 and 80 km/h.
  
  At the central collection point, the refuse goes into containers and the compressed air is filtered before being released into the atmosphere. The refuse stored in containers is removed by trucks as often as necessary, and taken to the relevant treatment points.
  
  
• Mobile system. In this system the chutes are connected to containers. Trucks are used to create suction, at certain fixed points, from which different containers can be emptied.

Furthermore, the different fractions to be collected can be dropped into the same box or in different boxes. In the first case, the different fractions must be put into different coloured bags so they can be sorted at the plant. Bags must be properly closed and be of sufficient quality to prevent them breaking during suction. In the second case, each valve holds back a different fraction and during suction only valves corresponding to the same fraction open.