Primarily a wet process, dust control is still required on the crushing and screening as well as packaging or bulk handling.
Various compounds added to the base resin enhance the plastics properties. Examples include fiberglass for strength, glass beads for weight reduction, colorants, oxidizers, etc. Dust created when handling these compounds prior to adding them to the resins offer a need for dust collection.
Thermosetting and Molding
These processes typically do not require dust collection, though other forms of emission control may be required.
Many molded items come from the mold ready to use, requiring no additional processing. Others require grinding mold parting lines and/or blasting of the surface before they are ready for use. Many of these operations will require local exhaust ventilation systems and dust collection.
Machining and Grinding
Machining and grinding plastics offers special challenges for dust collectors because of static charge, and dust characteristics. Donaldson Torit collectors can meet those challenges. As an example, most eyeglass lenses are machined polycarbonate with each of the grinders requiring some form of dust control and Donaldson Torit has over 500 collectors installed on Polycarbonate lens grinding.
Recycling conserves raw materials and energy and lowers the cost of production. Recycling has become a major objective of many industries and the plastics industry is a leading proponent, recycling everything from computer and copier cases to water bottles. In fact, in excess of 25% of water and soda bottles are recycled and over 1,600 businesses are involved in post consumer plastic recycling in the United States.
Plastic dust is a combustible material and those operations generating or handling plastic dust can require special mitigation efforts to minimize fire and explosion risks.