The washing and recycling technology of PET bottles is to convey the waste PET bottles through specific washing and recycling equipment and go through the impurity removal procedures (including label separation, bottle surface purification, bottle classification, metal rejection, etc.) After washing and purification treatment, it can finally be used as recycled PET raw material.
1. Brief introduction:
The bottle flakes washed by PACKER's equipment can be directly processed into POY filament, staple fibre, preform, PET packing tape, sheet and other products. After adjustment, the production line can also wash ABS, PVC and other plastics that can sink in water. The whole production line has a high degree of automation, requiring only 3-5 operators, and the output can be designed according to client requirements.
The water content of the cleaned bottle flakes is below 1%.
The composition of the production line: conveyor belt, label removing machine, sorting table, crusher, hot water steamer, screw elevator, high-speed friction cleaning machine, single (double) screw rinsing machine, centrifugal dehydrator, cyclone silo, electric control cabinet, etc.
2. Process flow of PET bottle washing line:
A De-Baler system
Before the bundled PET bottle bricks enter the cleaning section, they need to be disintegrated into individual units, which is conducive to the removal of contaminants (such as labels, sediment, metals, etc.) on the monomers in the subsequent process.
B, Thermal Label Shrink Separation System
PET bottles with heat shrink labels (mainly PVC, PET and OPS) cannot be washed to remove their labels. This system is to tear the label on the surface of the bottle so that the label is no longer attached to the bottle body, and then use a specific method to separate the broken label from the bottle body.
C, Bottle washing system
The main unit of this system is divided into two sections. The first section is the washing section. The material and the chemical water roll in the washing cylinder and rub against each other to achieve the cleaning effect. The second section is the separation section. Using gravity, the medicinal water can take away the main labels and other pollutants from the screen plate of the separation cylinder, so as to achieve the effect of separation.
D, Automatic sorting/manual sorting system
Based on NIR (Near Infrared) and visible light technology to identify plastics of different colours or materials, and eject the desired material (positive selection) or unwanted material (negative selection) through high-pressure air.
As the last quality check before the bottle enters the shredder, the following impurities are removed by manual identification and removal: non-PET bottles, variegated bottles, other plastics, metals, bottles with PVC labels, and Judgment of the foreign body in the bottle.
E, Crushing system
After the PET material enters the crusher, after several times of shearing, the PET materials of different sizes will be discharged from the crushing chamber respectively. The specially designed crusher can add water during the crushing process to allow the bottle flakes to perform the first friction cleaning.
In order to reduce the impurity of the final product to 100ppm, or even as low as 50ppm, the crushed bottle flakes are cleaned twice. The system is composed of hot water cleaning, high-speed friction cleaning, water medium separation matching automatic pharmaceutical water filtration system and an automatic dosing system. The close connection and the rational matching of functions can effectively remove bottle caps, bottle rings, and residues in the bottle. Oil and beverages inside, glue and other impurities outside.
F, Flake rinse tank system
After hot-washing the bottle flakes, there will still be some chemicals left on the surface, and the PH value of the surface of the bottle flakes tends to be neutral by continuous clear water rinsing. At the same time, the suspended matter remaining in the bottle flakes after hot washing will be further floated in this unit to ensure the cleanliness and transparency of the bottle flakes.
G, Drying system, mixing system, dust separation system and filling system
They respectively achieve the functions of drying, homogenizing impurity content, removing dust and filling and storing.
3. Each module of the production line
1) De-baler machine – breaks up the compacted and packed PET bottles
2) Sorter – removes possible stones, small pieces of metal and loose caps
3) Manual selection platform (optional) - Manual selection of PET bottles with different colours
4) Metal Detectors – Detects metals that may be contained in materials
5) Pre-washing machine – remove some of the sediment and the remaining liquid in the bottle, rub and rub the label to make it fall off
6) Crusher 1 (including feeding device) – crushing PET bottles with water
7) Spiral Washer 1 – Conveying and Washing
8) Crusher 2 – with water to further crush PET flakes to a smaller size
9) Spiral Washer 2 – Convey and Wash
10) Centrifuge 1 – Washing and drying PET flakes
11) Z Sorting System 1 - Remove some labels
12) High-temperature cooking pot - high-temperature washing PET bottles, washing oil and glue from bottle flakes
13) Rinse sedimentation tank (quantity of equipment depends on production requirements) – remove caps and labels, wash PET flakes
14) Centrifugal Dehydrator 2 – Washing and drying PET bottle flakes
15) Z-Type Sorting System 2 – Removal of possible remaining labels
16) bagging system
17) Control box
4. Equipment picture