Gomine Plastic Pyrolysis Plant: A Smarter Way to Recycle Waste Plastics

Through a high-temperature, oxygen-free process, plastic pyrolysis breaks down the long-chain polymers in plastics into smaller molecules, yielding products such as pyrolysis oil, combustible gas, and carbonaceous solids.

So, which types of plastic are suitable for pyrolysis? And how does a plastic pyrolysis production line actually work?

Which Plastics Are Suitable for Pyrolysis?

Not all plastics are suitable for direct processing in pyrolysis equipment. In general, PE, PP, PS, and certain types of ABS are the most common feedstocks for pyrolysis.

• PE (polyethylene): Includes both HDPE and LDPE; commonly found in plastic bags, packaging films, and plastic bottles.
• PP (polypropylene): Commonly found in food containers, bottle caps, and automotive parts.
• PS (polystyrene): Frequently present in foam plastics, disposable tableware, and packaging materials.
• ABS: Primarily used for electronic device casings, toys, and automotive components.

These plastics contain a high proportion of organic hydrocarbons, which—under the appropriate process conditions—can yield high-quality liquid products.

Why Do PET and PVC Require Special Handling?

A particularly critical step in plastic pyrolysis is the sorting of feedstock. If certain types of plastics are fed directly into a standard pyrolysis system, it can not only compromise product quality but also cause significant issues for the equipment and environmental protection processes.

PET

PET is typically found in items like beverage bottles and food packaging. Compared to PE or PP, it is actually not very well-suited for pyrolysis into oil. If there is too much PET in the feedstock, it will negatively affect the overall process, so it is best to separate it out beforehand.

PVC

PVC requires even greater caution. It contains chlorine, which can readily generate acidic gases—such as hydrogen chloride (HCl)—at high temperatures. These gases not only corrode equipment but also complicate downstream exhaust gas treatment.

• 💡Therefore, if the primary objective is to produce pyrolysis oil, it is generally best to minimize the amount of chlorine-containing plastics, such as PVC, that enter the pyrolysis system.

How Does a Plastic Pyrolysis Production Line Work?

A complete plastic pyrolysis process can be broadly divided into several steps:

① Feedstock pretreatment

First, sort the waste plastic to remove PVC, PET, and other impurities; then, depending on the specific requirements, proceed with washing, dewatering, and shredding to prepare the material for continuous feeding.

② High-Temperature Pyrolysis

The pretreated plastic is fed into a pyrolysis reactor, where it is heated in an oxygen-free or oxygen-deficient environment. As the temperature rises, the long molecular chains within the plastic gradually break down into smaller hydrocarbon molecules.

Factors such as pyrolysis temperature, heating rate, and reaction duration all influence the final product; therefore, process parameters must be adjusted according to the specific raw material used.

③ Condensation and Product Collection

The high-temperature oil and gas produced during pyrolysis enter a condensation system. Upon cooling, a portion condenses into liquid pyrolysis oil, while the lighter, non-condensable gases are recovered for use as combustible gas.

Solid residues generated during the reaction process are also collected.

What Products Can Be Obtained from the Pyrolysis Process?

A major benefit of plastic pyrolysis is its ability to transform waste plastic into several valuable resources:

• Pyrolysis oil: The primary liquid product. Depending on its quality and local regulations, it can be further processed or used as a feedstock for industrial fuel.
• Combustible gas: Non-condensable gases possess a certain calorific value and can be recycled back into the pyrolysis furnace for heating, thereby reducing the need for external fuel.
• Carbonaceous solids: Solid residues remaining after pyrolysis, which may require further processing or utilization depending on the raw material and the specific process employed.

In particular, recycling the combustible gas is highly effective for cost reduction; when utilized properly, it decreases the system’s reliance on external energy sources.

Plastic pyrolysis is far more than just “heating plastic to turn it into oil.” It is, in fact, a comprehensive system encompassing feedstock pre-treatment, the pyrolysis reaction itself, condensation and recovery, energy utilization, and environmental protection measures.

Gomine offers customized plastic pyrolysis solutions tailored to specific plastic feedstocks, processing capacities, and project requirements—helping clients effectively transform waste plastic into a valuable resource.