High-Purity PET Recycling for Micro-Denier Filament

The demand for recycled polyester continues to grow as manufacturers, brands and consumers place increasing importance on sustainable materials. PET bottles represent an important source of recyclable polyester, and advanced washing technology allows this valuable material to be recovered and converted into high-quality rPET flakes.

Micro-denier filament production requires a cleaner and more consistent PET feedstock than many conventional recycling applications. Contaminants, residual labels, adhesives, organic material, dust and foreign polymers can influence the performance of extrusion, filtration and spinning processes.

For this reason, the PET bottle washing process must provide effective separation and intensive cleaning before the material reaches the downstream pelletizing and spinning stages.

The EXTRUTEX Micro-Denier Filament Grade PET Washing Line has been developed around this requirement. Its process combines multiple mechanical and thermal cleaning stages with automated sorting and water-treatment technologies to produce a stable, high-purity PET flake stream.

Why Micro-Denier Recycled PET Is Important

Micro-denier polyester filament is increasingly used in products where softness, flexibility, surface feel and functional performance are important. Recycled PET can provide a secondary raw material for these applications while helping manufacturers increase recycled content in their products.

Recycled polyester filament can be used in textiles, technical fabrics, apparel, functional materials and other applications where fine filament structures provide specific performance characteristics.

EXTRUTEX Micro-Denier PET Washing Line Highlights

• Modular functional-unit design for flexible plant configuration and maintenance.
• Advanced bottle pre-washing for removal of loose dirt and surface contamination.
• Water circulation system designed to improve process-water utilization.
• rPET flake pre-heating before intensive washing.
• High-performance hot washing for intensive removal of difficult contamination.
• Inline sub-product collection for improved material separation and handling.
• Inline water treatment for improved process-water management.
• Clean workshop-oriented design for modern industrial recycling facilities.
• Removable platforms for easier equipment access and plant maintenance.
• Pneumatic conveying options for efficient movement of PET flakes between process stages.
• Low operational breakdown design supporting stable continuous production.
• Production management support for customers operating advanced PET recycling facilities.

Input Capacity: 1,500–9,000 kg/h

EXTRUTEX offers the Micro-Denier Filament Grade PET Bottle Washing Line with configurable input capacities from approximately 1,500 to 9,000 kg/h. The final system configuration depends on the incoming PET bottle quality, bale composition, contamination level, required output quality and downstream production requirements.

Micro-Denier Filament Grade PET Recycling Process

The EXTRUTEX process is designed as a continuous sequence of preparation, separation, washing, drying and quality-control stages. Each unit performs a specific function while working together as part of the complete PET recycling line.

1. PET Bottle De-Baling

Post-consumer PET bottles are generally delivered to the recycling facility in compressed bales. The automatic de-baling stage opens these compacted packages and prepares the bottles for continuous processing.

A stable feeding system is essential for a high-capacity PET washing plant. Controlled de-baling reduces manual intervention and provides a consistent material flow toward metal removal, label separation and pre-washing.

2. Metal Removal

Metal separation is positioned at appropriate points within the process to protect downstream equipment and reduce metallic contamination. Removing ferrous and other unwanted metal components helps improve equipment reliability and material cleanliness.

3. Label Removal

Labels and label materials represent an important source of contamination in PET bottle recycling. The EXTRUTEX label removal stage separates loose and attached label material before the bottles proceed further into the washing process.

Effective label separation also helps reduce the amount of lightweight foreign material entering the crusher and subsequent washing stages.

4. Bottle Pre-Washing

Bottle pre-washing removes loose dirt, dust, beverage residues and other surface contamination before crushing. This reduces the contamination load entering the intensive flake washing process.

The pre-washing system can be combined with process-water circulation and treatment technology to improve water utilization and maintain stable operating conditions.

5. Optical Bottle Sorting

Automated optical sorting provides an important quality-control barrier before PET bottles are converted into flakes. The system can identify and remove selected unwanted bottles, colors and materials according to the selected sorting technology.

Optical sorting reduces dependence on manual labor and helps create a more consistent PET feedstock for the crushing and washing stages.

6. Crushing

After preliminary sorting and cleaning, PET bottles enter the crushing stage. The bottles are converted into flakes with a controlled particle size suitable for subsequent thermal, mechanical and water-based cleaning.

Proper crushing is important because flake dimensions influence washing performance, drying efficiency and optical sorting accuracy.

7. rPET Flake Pre-Heating

Pre-heating provides an additional process stage before intensive hot washing. Bringing the PET flakes to an appropriate process temperature can help prepare the material for the subsequent thermal cleaning operation.

The pre-heating system can be integrated into the overall process according to feedstock characteristics and the selected plant configuration.

8. Intensive Hot Washing

Hot washing is one of the most important stages for producing high-quality PET flakes. PET bottle flakes can contain adhesives, organic residues, oils and other difficult contaminants that require intensive thermal and mechanical treatment.

The EXTRUTEX hot-washing process combines controlled temperature, washing chemistry, mechanical action and residence time to achieve intensive cleaning of the PET flakes. Process parameters can be adjusted according to the characteristics of the incoming material and the required output specification.

9. Friction Washing

Friction washing provides additional mechanical cleaning after the thermal washing stage. High-speed mechanical interaction helps detach remaining contaminants from the surface of PET flakes.

Combining hot washing with friction washing provides a multi-stage cleaning approach suitable for demanding rPET flake applications.

10. Rinsing

After intensive washing, the flakes are rinsed to remove residual washing chemicals, suspended particles and remaining contamination. Effective rinsing is essential for preparing the material for drying and final quality control.

11. Drying and Dust Removal

Washed PET flakes contain residual moisture and must be efficiently dewatered and dried before final sorting and packing. The EXTRUTEX drying system is integrated into the process to reduce moisture and prepare the flakes for downstream handling.

Dust removal provides another cleaning stage by extracting lightweight particles from the PET material. This contributes to a cleaner and more consistent final product.

12. Optical Flake Sorting

Optical flake sorting provides final separation of unwanted PET flakes, colors and foreign materials. This additional sorting stage is particularly important for high-quality filament applications where feedstock consistency is essential.

13. Blending and Online Inspection

After final sorting, the rPET flakes can be blended to improve material consistency. Online inspection allows the production team to monitor selected quality parameters and process conditions.

Centralized control and monitoring provide operators with a clearer overview of the recycling process and can support production analysis, maintenance planning and process optimization.

Major Equipment Configuration

Clean Workshop and Modular Plant Design

Modern PET recycling facilities require efficient use of production space as well as reliable equipment access. The EXTRUTEX system uses modular functional units that can be arranged according to the customer's available factory space and process requirements.

Removable platforms and pneumatic conveying options can simplify equipment access, material transportation and maintenance. The overall layout can be developed as a three-dimensional plant model before manufacturing, helping customers understand the complete arrangement of equipment, platforms, conveyors and service areas.

Water Treatment and Circulation

Water is an essential resource in PET bottle washing. Efficient water management therefore has a direct influence on plant operating costs and environmental performance.

EXTRUTEX can integrate inline water-treatment and circulation systems into the PET washing process. Process water can be treated and reused at appropriate stages, reducing unnecessary freshwater consumption and helping maintain stable washing conditions.

Downstream Applications of Micro-Denier Grade rPET

Clean recycled PET flakes produced by the washing line can be further processed through extrusion, melt filtration, pelletizing and spinning to manufacture recycled polyester filament.

• Micro-denier polyester filament
• High-density waterproof fabrics
• Anti-drilling and technical fabrics
• Functional absorption materials
• High-end knitted fabrics
• Recycled polyester apparel
• Underwear and skin-contact textile applications
• Filter materials
• Moisture-management and moisturizing textile materials
• Other recycled polyester filament products

EXTRUTEX Engineering and Manufacturing

EXTRUTEX combines Austrian engineering and design with industrial manufacturing in China. The PET recycling systems are developed around practical production requirements, process integration and long-term industrial operation.

Manufacturing is carried out in Nanjing and Shanghai, China, allowing EXTRUTEX to provide complete PET washing systems with competitive industrial manufacturing while maintaining strong engineering and process-development capabilities.

From compact PET recycling plants to large industrial installations, EXTRUTEX can develop equipment configurations according to feedstock characteristics, production capacity, factory layout and required rPET quality.

Why Choose the EXTRUTEX Micro-Denier PET Washing Line?

• Designed specifically for demanding recycled PET flake applications.
• Suitable for micro-denier filament-oriented rPET production.
• Configurable input capacity from approximately 1,500 to 9,000 kg/h.
• Modular functional-unit design.
• Integrated bottle pre-washing and water circulation options.
• rPET flake pre-heating and intensive hot washing.
• Friction washing and multi-stage rinsing.
• Optical bottle and flake sorting options.
• Inline water-treatment solutions.
• Online inspection and production monitoring.
• Removable platform and pneumatic conveying options.
• Designed and engineered by EXTRUTEX in Austria.
• Manufactured in Nanjing and Shanghai, China.