New Tech Converts Polyolefin Waste into Highvalue Recycled Pellets

Have you ever struggled with processing low-density polyethylene (PE) and polypropylene (PP) waste materials like films, woven bags, or non-woven fabric scraps? These seemingly troublesome plastic wastes can now be efficiently recycled into high-value regenerated pellets through an innovative solution—the crushing, compacting, and pelletizing production line.

Low-density, high-loft PE/PP waste materials like films and raffia present significant challenges for traditional extrusion pelletizing equipment. Their low bulk density and tendency to tangle lead to unstable feeding, often causing "bridging" or "blockage" that severely impacts subsequent melting, filtration, and pelletizing processes.

The crushing-compacting pelletizing technology introduces a crucial preprocessing stage before extrusion. This mechanical process shreds, mixes, heats, and initially densifies the loose waste materials, significantly improving their bulk density and flowability. The result is a more stable, continuous feed into the extruder, solving long-standing industry feeding problems while stabilizing the entire pelletizing process.

A typical crushing-compacting pelletizing production line achieves fully automated processing from rough treatment to refined production through precise process integration:

Waste materials are first conveyed to the crushing-compacting unit. An optional metal detector can identify and remove metal impurities at this early stage, protecting downstream equipment from damage.

High-speed rotating blades shred the waste while utilizing friction-generated heat to pre-warm the material and compact it. This transforms loose waste into a denser, more uniform material flow, establishing the foundation for stable extruder feeding.

The compacted material enters a single-screw extruder where it's thoroughly melted and homogenized. The vacuum devolatilization zone effectively removes moisture and volatile substances—particularly important when processing printed films, lightly cleaned materials, or mixed waste—significantly improving pellet stability and quality.

The molten plastic passes through an efficient melt filtration system. Automatic or semi-automatic screen changers continuously remove residual impurities, ensuring melt purity before it reaches the die, thereby enhancing the appearance quality and downstream application value of the recycled pellets.

The melt is cut into pellets at the die and immediately cooled in water. Water ring pelletizing technology produces uniformly shaped, density-stable pellets. Subsequent centrifugal or vibration screening ensures efficient drying for convenient transportation, packaging, and use.

The production line offers highly flexible design options that can be customized according to different material characteristics, output requirements, and target pellet quality. Key parameters like screw diameter, devolatilization section design, filtration precision, and pelletizing methods can all be adjusted to maximize production efficiency and product value.

• PE Film Waste: Various packaging films, industrial scraps, and waste films from soft material recovery streams (HDPE, LDPE, LLDPE)
• PP Raffia and Woven Bags: Woven bag scraps, FIBC cutting waste, raffia materials—all show significantly improved extrusion stability after pre-compaction
• Film Rolls and Edge Strips: Production waste like edge trims, rolls, and defective products, ensuring continuous stable pellet production
• Agricultural Films: Greenhouse covers, mulch films, and similar materials after cleaning to remove most moisture, soil, and ink
• Non-woven and Fiber Waste: Effectively processes PP non-woven waste and fiber residues, improving extrusion stability through densification
• Lightly Printed Waste: Dual-zone vacuum devolatilization effectively handles flexible waste with slight printing ink or residual volatiles, minimizing impact on pellet quality

Different production line models are available based on material cleanliness, bulk density, printing level, filtration requirements, and target output. Typical model output ranges are:

• GL85: 180–250 kg/h
• GL100: 300–400 kg/h
• GL130: 500–600 kg/h
• GL160: 700–800 kg/h
• GL180: 1000–1500 kg/h

The choice between equipment types primarily depends on material bulk density and feeding stability. For loose, low-density film waste, the crushing-compacting pelletizing line is superior due to its integrated preprocessing functionality.

It's an integrated pelletizing system combining crushing-compacting and extrusion units. The front-end crushing and compacting densifies low-density waste before melting, filtration, and pelletizing, achieving efficient one-stop recycling.

Primarily LDPE, LLDPE, HDPE films; PP films, woven bags, raffia, non-woven waste, edge trims, film rolls, and lightly printed flexible waste.

Vacuum devolatilization effectively removes residual moisture and volatile substances, reducing bubbles, odors, and structural defects in pellets. This is particularly crucial for cleaned or printed films, significantly improving pellet stability and performance.

The production line uses water ring die-face pelletizing technology, widely applied in PE/PP soft plastic pellet production for stable pellet cutting and uniform output.