Introduction

The global demand for sustainable materials has led to a high level of attention in the recycled plastic manufacturing industry. As environmental problems continue to intensify, industries around the world are turning to a circular economy model to reintegrate waste into the production cycle. Recycled plastics play a vital role in this model and provide a viable solution to the growing problem of plastic waste. However, the technology and processes involved in recycling plastics are very complex, and the industry faces many challenges in achieving efficiency and consistency.

A large amount of plastic waste enters the soil and ocean, seriously polluting the soil and water bodies and threatening human living space. How to reduce plastic pollution and realize the resource utilization of waste plastics is a common issue facing the world. This article explores the recycled plastic manufacturing technology in the recycled plastic manufacturing industry.

What is recycled plastic?

Recycled plastic refers to the process of recycling waste plastics through pre-treatment such as recycling, cleaning, and sorting, and then re-making them into plastic raw materials through physical or chemical methods such as melt granulation and modification. It is applied to textiles, food and beverage packaging, home building materials and other fields. It is one of the ways to achieve sustainable development of plastics.

The importance of recycled plastics

Plastics have become an indispensable part of modern life, from packaging to automotive parts. However, the durability of plastics not only makes them so useful, but also increases their environmental impact, as they can remain in the environment for hundreds of years. Recycling plastics not only reduces the amount of waste that ends up in landfills and oceans, but also saves natural resources by reducing the need for virgin plastic production.

Types of Recycled Plastics

Recycled plastics are categorized based on the source material and recycling process. The most common types include:

1. Post-consumer recycled plastics (PCR): These plastics come from household or commercial waste, such as used packaging and bottles.

2. Post-industrial recycled plastics (PIR): These come from manufacturing waste, such as scraps and offcuts from the production process.

3. Marine plastics: These are plastics collected from oceans, rivers, and other bodies of water, which are then processed and recycled.

Each type of recycled plastic has its own challenges and requires specific technologies to ensure that the final product meets industry standards.

Recycling Processes and Technologies

The recycled plastic manufacturing process typically involves several key steps: collection, sorting, cleaning, shredding, drying, melting, and extrusion pelletizing. However, advances in technology have introduced more sophisticated methods to improve efficiency and output quality.

1. Collection and Sorting

The initial stage of recycling involves the collection and sorting of plastic waste. Advanced sorting technologies, such as near-infrared (NIR) spectroscopy, have greatly improved the accuracy and speed of separating different types of plastics. These technologies can identify and sort plastics based on polymer type, color, and even the presence of contaminants, ensuring that the recycling process starts with a clean, well-sorted material stream.

Some projects with limited funding also choose to sort plastics manually.

2. Cleaning and Preparation

After sorting, the plastic waste is thoroughly cleaned to remove labels, adhesives, and other contaminants. Ultrasonic cleaning and chemical cleaning are among the technologies used to enhance this process, ensuring that the plastic is free of impurities that may affect the quality of the recycled material.

3. Crushing and Granulating

After cleaning, the plastic is crushed into small pieces or granulated into uniform particles. Advanced crushers and granulators now have features such as intelligent control systems and automatic adjustment mechanisms to optimize particle size and reduce energy consumption during the process.

The crushed plastic flakes are then melted and extruded into strips.

5. The extruded plastic strips pass through a cold water pool, cool down, and then enter the pelletizer to be cut into uniform-sized recycled plastic pellets.

6. Compounding and additive incorporation

To enhance the performance of recycled plastics, manufacturers usually add fillers, stabilizers and other additives during the compounding process. The latest compounding technology can precisely control the incorporation of these additives, so that the recycled plastic can meet specific performance standards, such as UV resistance or increased tensile strength.