Zig-Zag Air Classifier for Plastic Recycling
Engineered for high-purity recycling lines, this zig-zag column strips paper, film fines, and dust away from dense PET or HDPE flakes through tightly controlled airflow.
Integrate it after drying to improve flake quality, reduce light contamination, and protect downstream pelletizing or packaging performance.
- Removes light contaminants without damaging valuable flakes.
- Adjustable airflow profile for different polymers and contamination loads.
- Fits PET, HDPE, PP, film, and mixed rigid recycling applications.
See the Zig-Zag Column in Action
Watch how controlled airflow lifts light contaminants while clean flakes continue through the process.
Working Principle
A rising air column carries light fractions upward while gravity keeps dense flakes moving to the bottom outlet.
Light Fraction Extraction
Labels, film fines, and paper fibers are carried upward, collected through the top hood, and routed to dust control.
Clean Flake Discharge
Dense PET, HDPE, or PP flakes fall through the lower section, ready for conveying, packing, or pelletizing.
Adjustable Cut Point
Fan speed and damper settings can be tuned to match density, moisture, particle shape, and targeted purity.
Performance Advantages
Designed to deliver cleaner flakes, more stable downstream processing, and better resale value.
High-Purity Output
Removes the light contamination that mechanical separation alone often leaves behind.
Energy-Optimized Flow
Balanced blower and rotary valve pairing maintains separation velocity with modest power draw.
Compact Footprint
The vertical zig-zag column integrates above conveyors or mezzanines to save floor space.
Low Maintenance
Minimal moving parts and abrasion-resistant surfaces keep maintenance predictable and downtime low.
Applications & Commercial Impact
Use the zig-zag column to improve flake quality and increase downstream process stability across multiple recycling scenarios.
PET Bottle Flake Polishing
Pair with hot-wash systems to reduce label dust and move closer to premium bottle-to-bottle specifications.
HDPE Rigids Recycling
Removes light label fractions from blow-molded and injection-grade regrind before compounding.
Film & Flexible Reprocessing
Reduces light fines before extrusion to help limit gel defects and die build-up.
Technical Specifications
| Parameter | Standard Configuration | Notes |
|---|---|---|
| Blower Motor | 5.5 kW | High-efficiency motor for continuous duty operation. |
| Rotary Valve Motor | 1.5 kW | Sealed drive to maintain steady material discharge. |
| Rotary Valve Diameter | 270 mm | Abrasion-resistant rotor blades for extended service life. |
| Valve Speed | 50 RPM | Optimized for stable discharge and separation consistency. |
| Cyclone Separator | 600 L | Captures dust and fines before filter collection or bagging. |
Related Equipment
Thermal Dryer for Plastic Recycling
Reduce moisture to below 3% before zig-zag classification for more consistent separation.
Sink-Float Separation Tank
Use upstream density separation to remove floating PP and PE from heavier flake streams.
Friction Screw Washer
High-energy surface cleaning before drying and final air classification.
PET Bottle Recycling Line
See how the zig-zag air classifier integrates into a complete PET flake production system.
Warranty & Installation
1-Year Warranty
Coverage for core components with fast spare-parts support and technical follow-up.
On-Site Commissioning
Process engineers can tune dampers, fan curves, and cyclone ducting during startup.
Line Integration
Custom inlet and outlet transitions ensure easier matching with dryers, washers, and conveying systems.
Frequently Asked Questions
Where does the zig-zag classifier sit in the line?
It is typically positioned after drying so that flakes are free-flowing and light contaminants can be evacuated efficiently before packing or pelletizing.
Can it handle materials beyond PET or HDPE?
Yes. Any application requiring separation of light versus heavy fractions, including PP regrind, paper-plastic streams, or biomass fuel preparation, can benefit from the adjustable airflow design.
What routine maintenance is required?
Operators mainly inspect fan bearings, rotary valve blades, and dust collection points. With proper filtration, the system runs months between planned service stops.
What throughput ranges are available and how is sizing determined?
Standard systems cover roughly 300 to 3000 kg/h. Final sizing depends on polymer type, bulk density, flake geometry, moisture, and contaminant loading.
How is dust captured to meet local emission requirements?
The light fraction is routed to a cyclone and then a downstream filter such as a baghouse or cartridge collector. Sealed ducting and slight negative pressure prevent fugitive dust.
Is it washdown-ready and what are product-contact materials?
Product-contact surfaces are typically stainless steel, with 304 as standard and 316 optional. Washdown packages and CIP nozzles can be specified for high-hygiene lines.
Request a Proposal
Share your throughput target, material type, and contamination profile. We will return a tailored airflow model, layout suggestion, and quotation.
