Sieving Machine For PET Recycling Plant

In the process of plastic recycling, the screening link is one of the key processes to ensure the purity and quality of the finished product. The sieving machine for PET recycling plant is a key equipment for separating and classifying different particle sizes or partitions. It mainly processes polyethylene terephthalate materials, and common sources include discarded beverage bottles, food packaging, etc. After crushing and cleaning, the raw materials need to be screened to remove impurities, classify particle sizes, and improve the efficiency and quality of subsequent granulation or reuse.

Classification of sieving machines for PET recycling plant

1. Drum screen

Structural features: The screen is cylindrical and installed horizontally or slightly tilted; the screen drum rotates slowly around its axis, and the material gradually passes through the screen during rolling; it usually has a closed structure to prevent dust leakage.

Working principle: The material enters the drum from the feed inlet, and is constantly rolled and slid under the rotation of the drum, and gradually screens out components of different particle sizes under the action of gravity.

Application scenario: Pre-screening before PET bottle crushing is used to remove large impurities mixed in the bottle body; suitable for humid, easy to entangle or impurity-rich occasions; large feed volume and strong processing capacity.

2. Linear vibrating screen

Structural features: Usually driven by dual motors to produce linear vibration; the screen box is rectangular, and the material moves linearly along the screen surface; it can be equipped with multiple layers of screens to achieve multi-level particle size separation.

Working principle: The material jumps forward along the screen surface under the action of vibration, and the particles are graded layer by layer according to the particle size.

Application scenario: Particle size classification of fragments after PET bottle crushing; Screening out fine powder or oversized particles produced during crushing; Usually used for dry screening, and can also be applied to light wet materials.

3. Rotary Vibrating Screen

Structural features: Circular design, using vertical vibration motor to produce three-dimensional compound motion; can be equipped with 1~5 layers of screens, supporting multi-level screening.

Working principle: Through high-frequency vibration, the material can be quickly layered and screened, and materials of different particle sizes are discharged through different screen layers

Application scenario: High-precision screening of fine fragments and powders in PET recycling; final screening after washing or before drying; remove fine impurities and improve purity.

The role of sieving machine for PET recycling plant

① Impurity separation: Through the difference in screen aperture, large impurities (such as bottle caps, labels, metal fragments) and small particle pollutants (such as sand and glass) in PET waste are removed to improve the purity and quality of PET.

② Particle size standardization: Classify the crushed PET fragments by particle size (such as 3-8mm, 8-12mm) to adapt to different recycling process requirements:

Small particle size (<5mm): used to produce fibers and films.

Medium particle size (5-12mm): suitable for granulation and wire drawing.

Large particle size (>12mm): may need to be returned to the crusher for further processing.

Reducing energy consumption: Standardized particle size can optimize the melt extrusion process and reduce energy consumption by 10-15%

Working principle of sieving machine for PET recycling plant

The screening machine in the PET recycling plant is mainly used to separate and screen the recycled PET plastics for subsequent processing and reuse. Its working principle generally includes the following steps:

Feeding: Discarded PET bottles or other plastic materials are fed into the screening machine through a conveyor belt.

Screening: There are usually screens or screen plates of different sizes inside the screening machine, which are separated according to the size and shape of the plastic particles. Larger debris will be screened out, while PET plastics of the right size will continue to move forward.

Vibration: The sieving machine for PET recycling plant can use the vibration mechanism to make the material more evenly distributed on the screen, thereby improving the screening efficiency.

What are the advantages of the sieving machine for PET recycling plant?

High-precision sorting to improve the purity of raw materials: Through screens of different mesh sizes (such as 20-200 mesh), impurities such as labels, sand, unbroken bottle caps, fibers, etc. in PET fragments are removed step by step. The screening machine can ensure that the size of the crushed PET particles is uniform, avoiding the impact of too large or too small particles on the subsequent cleaning, granulation or melting process.

Improve recycling efficiency and reduce labor costs: The screening machine can run continuously for 24 hours, with a large processing capacity (such as the vibration screen can process up to 1-5 tons per hour), which greatly reduces the need for manual sorting. The sieving machine for PET recycling plant completes multi-level sorting at one time through the combined operation of coarse screening (20 mesh) + fine screening (80 mesh).

Reduce the waste of raw materials and improve economic benefits: through reasonable mesh screening (such as 60-80 mesh filtering and washing of fine impurities), reduce the mis-discharge of qualified PET fragments, and the recovery rate can reach more than 95%. The sieving machine for PET recycling plant can remove hard impurities in advance. Uniform particle size can improve granulation and melting efficiency.

Improve material purity: PET recycling plant screening machines can efficiently remove impurities in PET particles, such as paper scraps, metals, plastic fragments, etc., to ensure that the recycled PET materials are purer, which is conducive to subsequent processing and recycling.

Recommended mesh number of sieving machine for PET recycling plant

Purpose	Recommended mesh number of screen	Scope of application
Screening of coarse particles	10-20 mesh	Used to remove large particles, such as large plastic pieces, paper scraps and other impurities
Screening of medium and fine particles	30-50 mesh	Used to screen medium-sized particles and remove large plastics or impurities
Screening of fine particles	60-100 mesh	Used for screening fine particles, suitable for screening small plastic fragments, fibers, etc.
Screening of ultra-fine particles	120-200 mesh	Used for screening finer particles, suitable for plastic powder and fine impurities

Application of sieving machine for PET recycling plant

The application of sieving machine for PET recycling plant runs through the core links of the entire recycling process. Its value is reflected in improving recycling efficiency, ensuring the quality of recycled materials and promoting environmentally friendly production. It is mainly used for grading, removing impurities, color separation and homogenization of crushed PET fragments to ensure that the quality of recycled materials meets the requirements of subsequent processing.

The selection of a suitable screening machine should be determined based on the specific process flow of PET recycling, the processing volume requirements, the impurity content of the raw materials, and the quality standards of the final product. The sieving machine for PET recycling plant is an indispensable key equipment to ensure the efficient and stable operation of the recycling process and ultimately produce high-quality recycled PET products. It improves product quality and promotes the recycling of resources by removing various impurities. Usually, a PET recycling plant will use a combination of multiple types of screening machines to achieve the best separation effect.