Driven by global carbon-reduction mandates and China’s Ecology and Environment Code (effective August 15, 2026), chemical recycling capacity is targeted to reach 10% by 2030.

Converting low-value flexible plastics into pyrolysis oil requires upstream mechanical pre-treatment: low-speed dual-shaft shearing to de-agglomerate entangled films, multi-stage mechanical classification (magnetic separation, air classification, screening) to extract inorganic inerts, and single-shaft fine shredding to supply homogeneous feedstock for catalytic cracking and hydroprocessing reactors.

1. Policy Framework and Regulatory Mandates (2026–2030)

Regulatory policies are shifting post-consumer plastic recycling from mechanical methods toward chemical conversion and thermal cracking:

Ecology and Environment Code (August 15, 2026): Mandates increased recycled content ratios in manufactured goods, including electrical and electronic equipment.

15th Five-Year Development Guidelines for Comprehensive Plastic Utilization (2026–2030): Establishes institutional frameworks for chemical recycling, setting up technical access standards, dedicated R&D funding, and streamlined approval channels to achieve a 10% chemical recycling capacity share by 2030.

Carbon Offset & Emissions Trading: Advanced pyrolysis reduces greenhouse gas emissions to approximately 2,300.69kg CO2, compared to 4,847.09kg CO2ton for direct municipal incineration.

Chemical recycling projects are being integrated into voluntary carbon reduction frameworks (e.g., CCER).

2. Chemical Recycling Technical Pathways (Plastic-to-Oil)

Pyrolysis converts solid high-molecular-weight polymers back into liquid hydrocarbon feedstocks through anaerobic thermal cracking at elevated temperatures 400–500℃.

Core industrial routes include:

Thermal Pyrolysis + Catalytic Hydroprocessing:

Process Mechanics: Thermal cracking breaks down long-chain hydrocarbons into pyrolysis gas and liquid synthetic crude. Subsequent catalytic hydroprocessing purifies liquid fractions to produce high-grade naphtha and diesel blends (e.g., hydrotreated polypropylene pyrolysis oil matching EN590 diesel standards).

Catalytic Cracking:

Process Mechanics: Molecular sieve catalysts lower reaction temperature requirements 250–350℃, maximizing naphtha fraction yields (achieving up to 89.5% liquid product yield from polyethylene feeds).

Fully Electric Pyrolysis Systems:

Process Mechanics: Replaces fossil fuel heating with fully electrified heating systems, lowering direct process emissions throughout the cracking phase.

3. Pre-Treatment Engineering for Low-Value Waste Plastics

Summary & Key Specifications:

High-value rigid plastics (PET/HDPE bottles) have established mechanical recycling markets. However, low-value post-consumer films, single-use bags, and agricultural sheets (46% of total plastic waste) contain high organic moisture, entangled fibers, and abrasive inorganic debris (soil, sand, metals).

Directly feeding un-shredded flexible films into pyrolysis units causes feeding bridge blockages, localized over-carbonization (coking), and catalyst poisoning.

Harden Integrated Mechanical Pre-Treatment Workflow

To stabilize continuous chemical reactor feeding, Harden provides an engineered pre-treatment process:

Step 1: Primary Dual-Shaft Shredding (De-agglomeration)

• Mechanics: Low-speed, high-torque dual-shaft shear shredders tear open compacted plastic bundles and break down entangled film matrices without shaft wrapping.

Step 2: Multi-Stage Mechanical Classification (Inorganic Extraction)

• Mechanics: Magnetic separators remove ferrous metals; air classifiers segregate heavy inert fractions; disc/trommel screens extract sand, gravel, and organic residues to reduce ash content.

Step 3: Fine Shredding & Particle Standardization

• Mechanics: Single-shaft fine shredders reduce purified plastic fractions into a standardized output size, ensuring uniform heat absorption inside downstream reactors.

4. Industrial Closed-Loop Commercial Projects

Commercial scale-up relies on combining mechanical pre-treatment with downstream chemical refiners:

Feedstock-to-Resin Closed Loops: Post-consumer polyethylene packaging undergoes pre-treatment shredding, thermal pyrolysis, gas/liquid purification, and hydroprocessing to yield hydrotreated pyrolysis oil 180,000TPA and pyrolysis gas 42,000 TPA.

Petrochemical Integration: Pyrolysis oil is supplieds to petrochemical refineries as a direct replacement for virgin crude oil, producing virgin-grade polymers for circular packaging applications.

5. Conclusion

The commercial viability of converting low-value post-consumer plastics into liquid fuels and chemical feedstocks depends on front-end pre-treatment efficiency. By deploying low-speed dual-shaft shredding, automated mechanical classification, and fine particle homogenization, Harden pre-treatment systems remove inorganic abrasives, resolve material wrapping, and establish standardized feedstocks required for continuous industrial-scale chemical recycling facilities worldwide.