I. Transforming Recycled PET Bottle Flakes into High-Quality Food-Grade rPET Pellets
As global demand for sustainable packaging continues to rise, food-grade recycled PET (rPET) has emerged as one of the fastest-growing materials in the plastics industry. Beverage bottles, thermoformed sheets, food containers, and packaging products are increasingly incorporating high percentages of recycled PET to meet environmental regulations and corporate sustainability goals.
However, producing food-grade rPET pellets from post-consumer PET bottle flakes requires advanced processing technology. Key factors directly influencing the performance of the final product include moisture control, contaminant removal, Intrinsic Viscosity (IV) stability, melt filtration, and pellet quality.
To address these challenges, ACERETECH has designed a food-grade PET bottle flake pelletizing and extrusion line with a capacity of up to 3,000–3,500 kg/h, providing a comprehensive solution for transforming washed PET bottle flakes into premium-quality rPET pellets.
II. Why Food-Grade PET Recycling Requires Advanced Pelletizing Technology
Compared to conventional plastic recycling, PET recycling presents unique technical challenges:
PET is highly sensitive to moisture during processing.
Hydrolysis can reduce Intrinsic Viscosity (IV) and mechanical properties.
Contaminants and fines can compromise product quality.
Stable melt pressure is essential for consistent pellet production.
Food-grade applications demand stricter quality standards.
Therefore, a professional PET pelletizing system must integrate features such as crystallization, high-efficiency degassing, advanced filtration, precise melt control, and intelligent process monitoring.
III. ACERETECH Food-Grade PET Pelletizing Solution
Capacity: 3000–3500 kg/h
Raw Material: Washed PET flakes
Finished Product: Food-grade rPET pellets
Applications: PET sheets, thermoformed packaging, food containers, fibers, and packaging products
IV. PET Flake Pelletizing Process Flow
1. Crystallization System
The process begins by pre-crystallizing the PET flakes in a crystallizer prior to extrusion.
Key Advantages:
Prevents material bridging and adhesion
Improves feed stability
Reduces moisture-related defects
Enhances processing efficiency
Proper crystallization is crucial for maintaining stable extrusion performance and ensuring consistent pellet quality.
2. ACT105/220 Conical Twin-Screw Extruder
At the heart of the system is the ACT105/220 conical twin-screw extruder.
✅ Key Specifications
Screw diameter: 105/220 mm
Max. screw speed: 75 rpm
Output: 3000–3500 kg/h
✅ Advanced Screw Design
The screws feature a bimetallic construction, combining 38CrMoAlA nitrided steel with a nickel-based wear-resistant alloy.
Advantages include:
Excellent corrosion resistance
Superior wear resistance
High-temperature stability
Extended service life
✅ High-Efficiency Heating System
The barrel is equipped with infrared heaters, offering the following benefits:
Rapid heating
Reduced energy consumption
High heat transfer efficiency
Maintenance-free operation
Combined with efficient air cooling, the extrusion process remains highly stable even under continuous production conditions.
3. Heavy-Duty Gearbox
The gearbox utilizes nickel-molybdenum alloy gears designed for demanding industrial applications.
Features:
High-torque transmission
Low operating noise
Exceptional reliability
Service life exceeding 50,000 hours
The robust gearbox ensures long-term, stable operation even under high-output production conditions.
4. Single-Stage Vacuum Degassing System
One of the most critical steps in PET recycling is melt purification.
The extrusion line features a vacuum degassing chamber equipped with:
Liquid ring vacuum pump
Roots vacuum booster pump
Multi-stage vacuum system
Advantages:
Efficient moisture removal
Removal of volatile contaminants
Reduction of low-molecular-weight compounds
Secondary purification of the PET melt
This process significantly improves pellet quality and helps maintain the properties required for food-grade applications.
5. Automatic Back-Flushing Screen Changer
To ensure continuous filtration without interrupting production, the system employs an automatic back-flushing screen changer.
Advantages:
PLC-controlled automatic cleaning
Continuous operation without frequent screen changes
Higher filtration efficiency
Reduced manual labor
Extended production uptime
This technology is particularly important when processing post-consumer PET flakes that may contain residual contaminants.
6. Melt pump for precise pressure control
A high-performance melt pump is installed downstream of the filtration unit.
Functions:
Stabilizes melt pressure
Reduces output fluctuations
Improves pellet consistency
Enhances overall extrusion performance
Stable melt pressure is crucial for ensuring uniform pellet quality and reliable downstream processing.
7. Inline melt viscosity measurement system
To ensure consistent food-grade quality, the system is equipped with an inline melt viscosity measurement system.
This intelligent monitoring technology enables operators to:
Monitor melt viscosity in real-time
Track processing stability
Detect material fluctuations instantly
Optimize production parameters
Real-time viscosity monitoring provides robust support for maintaining consistent product quality and controlling intrinsic viscosity (IV).
8. Underwater pelletizing system
The final stage of the process utilizes an advanced underwater pelletizing system.
Advantages include:
Uniform pellet size
Smooth pellet surface
High production efficiency
Excellent pellet cooling
Fully automatic operation
The resulting rPET pellets are suitable for demanding applications such as food-grade sheet extrusion and thermoforming.
9. Intelligent centralized control system
The entire production line is managed by an intelligent PLC control system.
Key features:
Centralized operation
Real-time monitoring
Automatic process control
Data management
User-friendly interface
This intelligent control architecture maximizes production efficiency while minimizing the need for manual intervention.
V. Applications of food-grade rPET pellets
The recycled PET pellets produced by this system are widely used in:
Food-grade PET sheet production
Thermoformed packaging
Disposable food containers
Beverage packaging
Polyester fiber manufacturing
PET strapping products
Sustainable packaging solutions
As global demand for recycled materials continues to grow, high-quality food-grade rPET pellets have become a key material in the development of the circular economy.
VI. Why Choose ACERETECH PET Recycling Solutions?
ACERETECH specializes in comprehensive technologies for plastic recycling and extrusion, offering:
PET bottle washing lines
PET pelletizing systems
Food-grade rPET solutions
PET sheet extrusion lines
Plastic recycling plants
Turnkey plastic recycling projects
Leveraging extensive industry experience and successful installations worldwide, ACERETECH helps recyclers maximize product value while ensuring stable and efficient production.
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FAQ
These terms of service ("Terms", "Agreement") are an agreement between the website ("Website operator", "us", "we" or "our") and you ("User", "you" or "your"). This Agreement sets forth the general terms and conditions of your use of this website and any of its products or services (collectively, "Website" or "Services").
Q1. How do recycled PET pellets meet food-grade application requirements?
A: Producing food-grade rPET pellets requires strict control throughout the recycling process, including high-quality PET flake washing, effective decontamination, precise moisture control, vacuum degassing, melt filtration, and stable extrusion conditions. By combining crystallization, vacuum degassing, online viscosity monitoring, and advanced filtration technologies, the purity and consistency required for food-contact packaging applications are ensured.
These terms of service ("Terms", "Agreement") are an agreement between the website ("Website operator", "us", "we" or "our") and you ("User", "you" or "your"). This Agreement sets forth the general terms and conditions of your use of this website and any of its products or services (collectively, "Website" or "Services").
Q2. Why is Intrinsic Viscosity (IV) control crucial in PET recycling?
A: Intrinsic Viscosity (IV) directly affects the mechanical strength, thermoforming performance, and processability of recycled PET. Excessive moisture or improper processing can lead to PET degradation and a drop in IV values. This pelletizing line helps maintain material property stability and enhances the value of rPET products by integrating crystallization, controlled extrusion, vacuum degassing, and online melt viscosity measurement technologies.
These terms of service ("Terms", "Agreement") are an agreement between the website ("Website operator", "us", "we" or "our") and you ("User", "you" or "your"). This Agreement sets forth the general terms and conditions of your use of this website and any of its products or services (collectively, "Website" or "Services").
Q3. What types of PET materials can this pelletizing line process?
A: The system is designed to handle a wide range of PET feedstocks, including washed PET flakes derived from beverage bottles, water bottles, food packaging containers, and post-consumer PET waste. With proper washing and sorting, these materials can be converted into high-quality rPET pellets suitable for downstream manufacturing applications.
These terms of service ("Terms", "Agreement") are an agreement between the website ("Website operator", "us", "we" or "our") and you ("User", "you" or "your"). This Agreement sets forth the general terms and conditions of your use of this website and any of its products or services (collectively, "Website" or "Services").
Q4. What are the key advantages of underwater pelletizing technology in PET recycling?
A: Compared to traditional strand pelletizing, underwater pelletizing offers advantages such as more uniform pellet size, superior appearance, higher levels of automation, and greater production stability. It is particularly well-suited for high-capacity PET recycling lines, as consistent pellet quality and continuous operation are critical for downstream sheet extrusion and packaging production.
These terms of service ("Terms", "Agreement") are an agreement between the website ("Website operator", "us", "we" or "our") and you ("User", "you" or "your"). This Agreement sets forth the general terms and conditions of your use of this website and any of its products or services (collectively, "Website" or "Services").
Q5. What products can be manufactured using recycled PET pellets?
A: The food-grade rPET pellets produced by this system can be widely used in PET sheet extrusion, thermoformed food trays, disposable food containers, beverage packaging, polyester fibers, PET strapping, and other sustainable packaging products. As global regulations increasingly encourage the use of recycled materials, high-quality rPET pellets are becoming a vital raw material for circular economy manufacturing.