Feeding and Preprocessing System

Function: Receives loose or baled mixed film waste from the packaging station.

Equipment: Chain plate conveyor, belt conveyor, large shredder/bale breaker.

Process: Large bales of film waste are transported to the shredder, which tears them into smaller pieces for uniform dispersion and sorting.

Bag Breaking and Screening System

Function: Breaks open any garbage bags that may be mixed with the film and screens out most non-film impurities (such as sand, glass fragments, paper scraps, etc.).

Equipment: Bag breaker, drum screen/bounce screen.

Process: The shredded material passes through the drum screen, where small particle impurities (<50mm) are separated through the screen holes, while light films are carried forward by the screening cylinder.

Magnetic and Air Separation System

Function: Removes metal and heavy material impurities.

Equipment:

• Magnetic separator: Usually installed above the conveyor belt to attract ferrous metals (such as bottle caps and wires).
• Air separator: Utilizes the density difference between the light films and heavy materials (like stones, bottle caps, and glass fragments) to blow the lightweight films onto another conveyor belt, while heavy materials drop directly down due to gravity for collection.

Near-Infrared (NIR) Spectroscopy Sorter:

Principle: Different types of plastics (such as PE, PP, PVC) absorb and reflect near-infrared light differently. Sensors scan the material and instantly analyze its spectrum, using high-speed air valves to blow different types of films into separate collection bins.

Function: This is the primary sorting method used for material separation (e.g., separating PE from PP).

Color Sorter:

Principle: Uses high-resolution CCD cameras to identify the color of the materials (such as transparent, blue, black, etc.).

Function: After or before material sorting, further sorts by color to meet downstream customer requirements for recycled material color. For example, separating transparent PE film from colored PE film.

Electrostatic Separator (ESD):

Principle: Utilizes the differences in charges generated by friction between different materials, allowing them to be separated in a high-voltage electric field due to differing forces.

Function: Particularly suitable for separating plastics with very close densities or as a supplementary purification method after NIR sorting.