How does a materials recovery facility sort mixed recyclables?

A materials recovery facility (MRF) sorts mixed recyclables using a combination of mechanical systems and manual labor to prepare materials for manufacturing.12

Mechanical Sorting Processes

Modern facilities utilize a series of conveyors and specialized equipment to separate items based on their physical properties:

• Electromagnetic Separators: These remove steel cans from the waste stream.2
• Vibrating Screens: These are used to sift out broken glass and other small contaminants.2
• Air Classifiers: These use air currents to separate lighter materials, such as aluminum and plastic containers, from heavier items like glass.2
• Eddy-Current Separators: These devices repel aluminum, effectively separating it from plastics on the conveyor belt.2
• Optical Scanners: Advanced facilities employ ultraviolet scanners to identify and sort various materials, including different types of plastic, simultaneously.1

Manual and Integrated Sorting

While automated systems handle much of the volume, human workers augment the process by manually sorting items to ensure higher purity. In some facilities, glass is sorted by color by hand. Once sorted, materials are processed—often through shredding, pulping, or melting—to be sold as raw commodities for new products.123