Rigid Plastic Granulating Pelletizing Line

The SUHUI rigid plastic granulating pelletizing line processes rigid plastic waste including HDPE, PP, PS, ABS, and mixed rigid plastics into high-quality uniform recycled pellets. Designed for industrial scrap, post-consumer packaging, and manufacturing offcuts, it transforms bulky rigid plastic waste into clean, reusable raw material for injection molding, blow molding, and extrusion applications.

The line integrates heavy-duty granulating, twin-screw extrusion, multi-stage melt filtration, and precision pelletizing technologies to handle the toughest rigid plastic materials consistently and efficiently. A multi-stage screen changer removes fine contaminants from the melt, ensuring pellet purity for demanding downstream applications.

Scalable from 300 to 3,000 kg/h, the SUHUI rigid plastic pelletizing line serves small recycling operations through to large-scale industrial plastic reprocessing facilities. Quick material changeover capability allows the same line to process different rigid plastic types with minimal downtime.

Key Features of SUHUI Rigid Plastic Granulating Pelletizing Line

• Heavy-Duty Granulator: High-speed granulator with hardened alloy steel blades reduces rigid plastic waste into uniform 3–8 mm granules for consistent, stable feeding into the extruder.
• High-Torque Twin-Screw Extruder: Co-rotating or counter-rotating twin-screw design ensures thorough melting, homogenization, and degassing of mixed rigid plastics and additives.
• Multi-Stage Melt Filtration: Continuous or discontinuous screen changers remove fine metal particles, unmelted contamination, and other impurities from the melt stream for high-purity pellet output.
• Precision Pelletizing: Underwater pelletizing or strand pelletizing systems produce uniform 2–5 mm recycled pellets with consistent geometry and low fines generation.
• Broad Material Compatibility: Processes HDPE, PP, PS, ABS, and mixed rigid plastics with quick parameter adjustments for different material types and melt flow indices.
• Dust-Free Closed-Loop Cooling: Enclosed water cooling and vacuum systems minimize airborne plastic particles during granulating and pelletizing operations.
• PLC Automated Control: Touchscreen control system monitors and adjusts barrel temperature, screw speed, melt pressure, and output quality parameters in real time.
• Energy Recovery System: Heat exchangers capture and reuse thermal energy from the extrusion process to reduce overall power consumption.

Rigid Plastic Granulating Pelletizing Process Workflow

1. Pre-Sorting & Inspection: Rigid plastic waste is inspected and sorted to remove incompatible materials including rubber, metals, and contaminated pieces that would affect pellet quality.
2. Coarse Crushing: Bulky rigid plastic items such as crates, pipes, containers, and profile scraps are fed into a primary crusher or shredder for initial size reduction.
3. Granulating: Crushed material passes through a heavy-duty granulator equipped with hardened blades, reducing it to uniform 3–8 mm granules for consistent extruder feeding.
4. Drying (Optional): Moisture-sensitive plastics such as ABS or nylon-containing blends are pre-dried in a dehumidifying dryer to below 0.5% moisture to prevent steam bubbles and surface defects in the final pellets.
5. Extrusion & Melt Filtration: Granules are fed into the twin-screw extruder where they are melted, homogenized, and degassed. The melt passes through a screen changer that filters out fine contaminants and unmelted particles.
6. Pelletizing: The filtered melt is extruded through a die head and cut into uniform 2–5 mm pellets using either an underwater pelletizing system (for soft plastics) or a strand pelletizing unit (for rigid plastics).
7. Cooling & Dehydration: Pellets are water-cooled in a bath or spray system to solidify, then passed through a centrifugal spinner to remove surface water.
8. Screening: Vibrating sieves separate on-spec pellets from undersized fines and oversized irregular pieces, ensuring uniform particle size distribution.
9. Packaging: Finished recycled pellets are conveyed to storage silos or automatically weighed and bagged for sale or use in injection molding, blow molding, or extrusion production lines.

Frequently Asked Questions

What types of rigid plastic can the SUHUI granulating pelletizing line process?

The line processes a wide range of rigid plastic waste including HDPE, PP, PS, ABS, and mixed rigid plastics sourced from industrial scrap, post-consumer packaging, and manufacturing offcuts. Quick parameter adjustments allow the same line to handle different material types and melt flow indices with minimal changeover time.

What is the output capacity range of the rigid plastic granulating pelletizing line?

The SUHUI rigid plastic pelletizing line is available in configurations from 300 to 3,000 kg/h, serving small recycling operations through to large-scale industrial facilities. SUHUI engineers will recommend the appropriate model based on feedstock volume, material type, and contamination level.

What pellet size does the line produce?

The line produces uniform 2–5 mm recycled pellets using either underwater pelletizing or strand pelletizing systems. A vibratory screening stage removes fines and oversized pieces to ensure consistent particle size distribution suitable for injection molding, blow molding, and extrusion applications.

Is pre-drying required before extrusion?

Pre-drying is optional and material-dependent. Moisture-sensitive plastics such as ABS or nylon-containing blends are pre-dried to below 0.5% moisture to prevent steam bubbles and surface defects in the final pellets. Standard HDPE and PP rigid plastics typically do not require pre-drying unless heavily contaminated or wet.

How does the multi-stage melt filtration system work?

Granules melted in the twin-screw extruder pass through a continuous or discontinuous screen changer that removes fine metal particles, unmelted contamination, and other impurities from the melt stream. This filtration step ensures high pellet purity for demanding downstream applications including technical plastics compounding.

What downstream applications are the recycled pellets suitable for?

Recycled PP and HDPE pellets produced by this line are suitable for injection molding, blow molding, and extrusion applications including pipes, containers, packaging, and profile products. Pellet purity and geometry are maintained by the melt filtration and screening stages to meet the requirements of demanding manufacturing processes.