{"id":10570,"date":"2026-11-12T16:04:46","date_gmt":"2026-11-12T08:04:46","guid":{"rendered":"https:\/\/shuliyplastic.com\/?p=10570"},"modified":"2026-11-12T17:01:49","modified_gmt":"2026-11-12T09:01:49","slug":"how-to-improve-pet-flakes-purity","status":"publish","type":"post","link":"https:\/\/shuliyplastic.com\/de\/how-to-improve-pet-flakes-purity\/","title":{"rendered":"How to Improve PET Flakes Purity in a PET Bottle Washing Line?"},"content":{"rendered":"

PET flakes purity<\/strong> is one of the most important factors affecting the quality and application of recycled PET flakes. During PET bottle recycling, impurities such as bottle labels, adhesive residues, sand, metal particles, PVC labels, and other plastics can remain in the material if they are not properly removed. These contaminants may affect the appearance, processing performance, and final quality of recycled PET flakes. Therefore, choosing the right PET bottle washing line and arranging each cleaning stage properly are essential for improving PET Flakes Purity.<\/p>\n\n\n\n

At Shuliy, we provide complete PET bottle washing lines<\/a><\/strong> designed to process waste PET bottles into clean, reusable plastic flakes. Our standard process includes a trommel screen, label remover, plastic crusher, floating tank, hot washing tank, friction washer, rinsing tank, dryer, and air classifier. Each machine plays a specific role in removing different types of contaminants.<\/p>\n\n\n\n

\n
\"Recycled
Recycled PET Flakes<\/figcaption><\/figure>\n\n\n\n
\"PET-Flaschenflocken\"
PET-Flaschenflocken<\/figcaption><\/figure>\n\n\n\n
\"green
green flakes<\/figcaption><\/figure>\n<\/figure>\n\n\n\n

1. What Contaminants Affect PET Flakes Purity?<\/h2>\n\n\n\n

Before improving PET flakes purity, it is important to understand where impurities come from and how they affect the recycling process.<\/p>\n\n\n\n

Type of impurity<\/th>Main source<\/th>Potential impact<\/th><\/tr>
Bottle labels<\/td>Paper or plastic labels attached to PET bottles<\/td>Affect flake appearance and increase foreign material content<\/td><\/tr>
Adhesive residues<\/td>Glue used to attach bottle labels<\/td>Remain on flakes and reduce cleanliness<\/td><\/tr>
Sand and soil<\/td>Bottles collected from outdoor or waste environments<\/td>Increase ash content and contaminate the material<\/td><\/tr>
Metal particles<\/td>Bottle caps, rings, and other metal objects<\/td>Damage equipment and contaminate recycled flakes<\/td><\/tr>
PVC plastics<\/td>PVC labels, bottles, or other mixed plastic waste<\/td>Affect PET processing and final product quality<\/td><\/tr>
PP and PE plastics<\/td>Bottle caps, rings, and other plastic packaging<\/td>Mix with PET flakes and reduce material purity<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Different impurities require different removal methods. For example, labels should be removed before or during washing, adhesive residues need hot washing and friction, while PVC and other floating plastics can be separated through density-based separation.<\/p>\n\n\n\n

\n
\"PET
PET plastic bottles<\/figcaption><\/figure>\n\n\n\n
\"PP
PP bottle caps<\/figcaption><\/figure>\n\n\n\n
\"blue
blue and white flakes<\/figcaption><\/figure>\n<\/figure>\n\n\n\n

2. How to Remove Labels from Waste PET Bottles?<\/h2>\n\n\n\n

Labels are among the most common contaminants in PET bottle recycling. They may be made of paper, PVC, PP, or PE, and different label materials require different separation methods.<\/p>\n\n\n\n

Our PET bottle washing plant uses two main stages to handle labels.<\/p>\n\n\n\n

Trommel Screen: Removing Loose Impurities<\/strong><\/p>\n\n\n\n

Der Trommelsieb<\/a><\/strong> is installed at the beginning of the PET bottle washing process. As waste bottles move through the rotating screen, loose materials such as sand, soil, small stones, and other debris can fall through the screen openings.<\/p>\n\n\n\n

This reduces the amount of unwanted material entering the following machines and helps protect downstream equipment.<\/p>\n\n\n\n

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\"Trommel
Trommel Screen for PET Bottle Recycling<\/figcaption><\/figure>\n\n\n\n
\"Inside
Inside the Trommel Screen<\/figcaption><\/figure>\n<\/figure>\n\n\n\n

Label Remover: Separating Bottle Labels<\/strong><\/p>\n\n\n\n

After screening, the PET bottles enter the label remover<\/a><\/strong>. Through mechanical friction and impact, the machine loosens and removes labels attached to the bottle surfaces.<\/p>\n\n\n\n

This step reduces the label content before crushing and washing. It also helps improve the working efficiency of subsequent separation equipment.<\/p>\n\n\n\n

\n
\"PET
PET Bottle Laber Remover Machine<\/figcaption><\/figure>\n\n\n\n
\"PET
PET Bottle Laber Remover Working<\/figcaption><\/figure>\n<\/figure>\n\n\n\n

3. How to Remove Glue and Adhesive Residues from PET Flakes?<\/h2>\n\n\n\n

Removing labels does not necessarily mean all adhesive residues have been eliminated. Some glue remains attached to the PET bottle surface and may still be present after crushing.<\/p>\n\n\n\n

To improve PET Flakes Purity, our washing line uses a combination of hot washing and friction cleaning.<\/p>\n\n\n\n

Warmwaschtank<\/strong><\/p>\n\n\n\n

After crushing and floating separation, PET flakes enter the hei\u00dfer Waschtank<\/a><\/strong>. Heated water and suitable cleaning agents help soften and loosen adhesive residues, oil stains, and other stubborn contaminants.<\/p>\n\n\n\n

Hot washing is particularly useful for PET bottles with strong label adhesive or surface contamination.<\/p>\n\n\n\n

\"PET
PET Flakes Hot Washing Machine<\/figcaption><\/figure>\n\n\n\n

Friction Washer<\/strong><\/p>\n\n\n\n

Der friction washer<\/a><\/strong> uses high-speed mechanical friction to remove loosened glue, dirt, and other residues from the surface of PET flakes.<\/p>\n\n\n\n

It helps clean the material more thoroughly and removes contaminants that may remain after hot washing.<\/p>\n\n\n\n

The combination of hot washing and friction cleaning is an important part of improving PET Flakes Purity, especially when processing heavily contaminated post-consumer PET bottles.<\/p>\n\n\n\n

\"Friktionswaschmaschine\"
Friktionswaschmaschine<\/figcaption><\/figure>\n\n\n\n

4. How to Remove Sand, Soil, and Other Heavy Impurities?<\/h2>\n\n\n\n

Waste PET bottles often contain sand, soil, small stones, and other heavy contaminants. If these materials enter the crushing and washing stages, they may increase equipment wear and affect the cleanliness of the final flakes.<\/p>\n\n\n\n

Unser Waschanlage f\u00fcr PET-Flaschen<\/a><\/strong> uses two stages to deal with these impurities.<\/p>\n\n\n\n

Trommel Screening Before Crushing<\/strong><\/p>\n\n\n\n

The trommel screen removes loose sand, soil, and small debris before the bottles enter the crusher. Early removal reduces the contamination load in the washing system.<\/p>\n\n\n\n

Floating Tank: Separating Heavy and Light Materials<\/strong><\/p>\n\n\n\n

After crushing, PET flakes enter the floating tank. The separation process is based on differences in material density.<\/p>\n\n\n\n

PET flakes generally sink in water, while PP and PE materials, including many bottle caps and rings, float on the water surface. Other floating contaminants can also be removed during this stage.<\/p>\n\n\n\n

Heavy impurities such as stones and some dense foreign materials may settle at the bottom, depending on their density and size.<\/p>\n\n\n\n

The floating tank therefore helps separate PET flakes from a variety of unwanted materials before they enter the hot washing process.<\/p>\n\n\n\n

\n
\"Sink
Sink Float Tanks Plastic Scraps Separation<\/figcaption><\/figure>\n\n\n\n
\"Floating
Floating Bottle Caps on the Water Surface<\/figcaption><\/figure>\n\n\n\n
\"PET
PET Flakes After Cap Separation<\/figcaption><\/figure>\n<\/figure>\n\n\n\n

5. How to Remove Metal and PVC Contaminants?<\/h2>\n\n\n\n

Metal and PVC contamination require particular attention because they can seriously affect the quality of recycled PET flakes.<\/p>\n\n\n\n

Metal Contamination<\/strong><\/p>\n\n\n\n

Metal objects may come from bottle caps, packaging waste, or other materials mixed with collected PET bottles.<\/p>\n\n\n\n

The trommel screen can remove some loose metal debris, while the label remover and subsequent separation stages help remove other unwanted materials.<\/p>\n\n\n\n

However, small metal particles may remain after these stages. For applications with strict purity requirements, we recommend adding a magnetic separator or metal detector at an appropriate position in the production line.<\/p>\n\n\n\n

PVC Contamination<\/strong><\/p>\n\n\n\n

PVC is one of the most problematic contaminants in PET recycling. PVC bottles or labels may enter the recycling process together with PET bottles.<\/p>\n\n\n\n

PVC has a higher density than water, so it generally sinks in the Sink-Schwimmer-Trenntank<\/a><\/strong> together with PET flakes. This means ordinary floating separation cannot reliably separate PVC from PET.<\/p>\n\n\n\n

For better PET Flakes Purity, PVC labels should be removed as early as possible through proper label identification, mechanical label removal, and effective sorting before or after crushing.<\/p>\n\n\n\n

For applications requiring higher purity, additional sorting equipment, such as optical sorting systems, can be considered according to the raw material composition and final product requirements.<\/p>\n\n\n\n

6. How to Remove Residual Dirt and Fine Plastic Contaminants?<\/h2>\n\n\n\n

Even after screening, crushing, and hot washing, some fine dirt and residual contaminants may remain on the PET flakes.<\/p>\n\n\n\n

Our washing line uses a rinsing tank, dryer, and air classifier to further improve the cleanliness of the finished material.<\/p>\n\n\n\n

Sp\u00fcltank<\/strong><\/p>\n\n\n\n

After friction washing, PET flakes enter the rinsing tank for further cleaning. Clean water helps wash away residual detergent, loosened dirt, and fine impurities.<\/p>\n\n\n\n

Proper water circulation and regular water replacement are important for maintaining stable washing performance.<\/p>\n\n\n\n

Dryer<\/strong><\/p>\n\n\n\n

After rinsing, the PET flakes enter the Plastiktrocknermaschine<\/a><\/strong> to remove surface moisture.<\/p>\n\n\n\n

Effective drying is important for subsequent storage, packaging, and processing. Excessive moisture may cause problems during downstream extrusion and pelletizing.<\/p>\n\n\n\n

\"Plastiktrocknermaschine\"
Plastiktrocknermaschine<\/figcaption><\/figure>\n\n\n\n

Air Classifier<\/strong><\/p>\n\n\n\n

The air classifier uses airflow to separate lightweight materials from PET flakes. It can help remove residual paper pieces, labels, fibers, and other lightweight contaminants.<\/p>\n\n\n\n

This final separation stage further improves the appearance and cleanliness of the finished PET flakes.<\/p>\n\n\n\n

\"Air
Air Classifier<\/figcaption><\/figure>\n\n\n\n

7. Complete PET Bottle Washing Line for Higher PET Flakes Purity<\/h2>\n\n\n\n

Improving PET flakes purity does not depend on a single machine. It requires multiple processing stages working together to remove different contaminants.<\/p>\n\n\n\n

Our standard PET bottle washing line follows this process:<\/p>\n\n\n\n

    \n
  1. Trommel Screen<\/a>:<\/strong> Removes loose sand, soil, and small debris from waste PET bottles.<\/li>\n\n\n\n
  2. Label Remover<\/a>:<\/strong> Mechanically removes labels attached to bottle surfaces.<\/li>\n\n\n\n
  3. Kunststoffbrecher<\/a>:<\/strong> Crushes PET bottles into smaller flakes for easier washing and separation.<\/li>\n\n\n\n
  4. Sink Float Plastic Separation<\/a>:<\/strong> Separates sinking PET flakes from floating PP and PE caps, rings, and other light materials.<\/li>\n\n\n\n
  5. Warmwaschtank<\/a>:<\/strong> Uses heated water and cleaning agents to remove adhesive residues, oil, and stubborn dirt.<\/li>\n\n\n\n
  6. Friction Washer<\/a>:<\/strong> Uses mechanical friction to further clean the PET flakes.<\/li>\n\n\n\n
  7. Rinsing Tank:<\/strong> Removes residual detergent and fine contaminants.<\/li>\n\n\n\n
  8. Dryer<\/a>:<\/strong> Reduces moisture content in the washed PET flakes.<\/li>\n\n\n\n
  9. Air Classifier:<\/strong> Separates lightweight paper, fibers, and other residual materials.<\/li>\n<\/ol>\n\n\n\n

    Each stage contributes to the overall cleaning result. By selecting suitable equipment and adjusting operating parameters according to the raw materials, customers can obtain cleaner PET flakes for subsequent recycling and processing.<\/p>\n\n\n\n

    \n
    \"Recyclinglinie
    Recyclinglinie f\u00fcr PET-Flaschen<\/figcaption><\/figure>\n\n\n\n
    \"Recyclinganlage
    Recyclinganlage f\u00fcr PET-Flaschen<\/figcaption><\/figure>\n<\/figure>\n\n\n\n

    8. How to Choose the Right PET Bottle Washing Line?<\/h2>\n\n\n\n

    The required PET flakes purity depends on the quality of the incoming bottles and the intended application of the recycled flakes.<\/p>\n\n\n\n

    Before selecting a PET bottle washing line, we recommend considering the following factors:<\/p>\n\n\n\n