Ldpe Sorting Machine | AISORT

Application Overview — Plastic Recycling

LDPE Sorting in Modern Recycling Facilities

Low-density polyethylene (LDPE) and linear low-density polyethylene (LLDPE) dominate the flexible packaging stream — films, bags, wraps, and pouches. LDPE film recycling is technically challenging because film behaves unpredictably on sorting equipment (folding, wrapping, floating), but the material has strong end-markets in construction film, bin liners, and composite lumber.

Material Characteristics and Sorting Challenges

LDPE sorting challenges: film materials wrap around conveyor rollers and bridge across chutes, requiring specialized handling; LDPE and LLDPE have nearly identical NIR spectra, making them difficult to separate from each other; multi-layer films (LDPE/PA, LDPE/PET) cannot be mechanically recycled without compatibilizers; and film is often contaminated with food residues, labels, and paper receipts.

Recommended Sorting Technology Stack

NIR (polymer identification: LDPE/LLDPE vs PP film vs PET film) + 3D laser (film vs rigid detection) + RGB (color sorting: clear/natural vs printed). Specialized film handling: high-friction conveyors, air-assist separation, anti-static systems. Pre-wash recommended for food-contaminated film. Throughput: 1-5 t/h for film lines.

Performance Benchmarks

MetricTarget
LDPE Purity>95%
PP Film Removal<3%
Throughput1-5 t/h (film)
Film Thickness10-200μm

These benchmarks represent achievable performance with modern sensor-based sorting equipment, assuming properly sized, well-maintained equipment operating on representative feedstock. Actual results depend on specific material composition, throughput, and operating conditions.