Herbold (Smithfield, RI) can custom configure Wash Plants for polyolefins capable of producing high-quality, food grade recyclates. While each wash plant is designed around the user’s specific requirements and facility characteristics, all feature a multi-stage process usually consisting of pre-shredding, pre-washing / initial separation, granulation, high density separation and drying. Specifically:
- Pre-shredding is typically done in a single-shaft shredder such as the Herbold 60/120. With a 23.5” diameter rotor and 60 individual knives, these rugged machines can accept entire bales of contaminated waste and process up to 13,000 lbs. per hour.
- Washing takes place in a VWE-60 pre-washing unit which employs a 3-step process of sink/swim to remove heavy materials, intensive spray wash to loosen and remove embedded sediment and an additional sink/swim to further eliminate remaining sediment.
- Further size reduction takes place in a wet granulator such as the Herbold 80/120. The wet operation provides additional separation of particles and contaminants from materials.
- Additional high-density separation of contaminants and recyclate occurs in a Hydrocyclone. The extreme centrifugal force of the Hydrocylcone provides separation that exceeds conventional methods by a factor of 15 ensuring the level of purity necessary for food grade recyclate.
- After final separation, materials are conveyed to either a mechanical or thermal dryer for removal of residual moisture prior to use or storage.