A major advantage of powder coatings over liquid paint-reuse overspray powder

A major advantage of powder coatings over liquid paint systems is the ability to reuse powder that does not adhere to an object (overspray).

Air and powder are separated by either a cyclone or a filter system, as illustrated.

Spraying booth with cyclone for recycling powder

Spraying booth with cyclone for recycling powder

Powder that is recycled will be recollected in the powder hopper. Particles which are more easily charged adhere themselves to the object whilst the proportion being recycled are of another particle distribution size than that of virgin powder. The relationship between small and large powder particle size has significant meaning regarding spraying properties and consequently the end result.

Spraying booth with filter recycling

Spraying booth with filter recycling

Recycled powder will always have properties that differ from virgin powder. In order to maintain a constant composition it is always an advantage to keep the volume of reused powder to a minimum and continuously return any recycled powder to the powder hopper.