Why Fully Continuous Plastic Pyrolysis Shows Great Promise

In the past, the plastic pyrolysis industry primarily focused on converting waste plastic into fuel oil. The industry is now shifting toward chemical recycling, the high-value utilization of pyrolysis oil, and large-scale continuous production. Fully continuous plastic pyrolysis plant represents the most viable pathway for the industrial-scale chemical recycling of waste plastics.

Advantages of Fully Continuous Plastic Pyrolysis

1. Continuous, Stable Operation and High Capacity: Featuring sealed, continuous feeding and the continuous output of pyrolysis oil and carbon black, these systems can operate over long cycles. This eliminates the need for repeated heating, cooling, and manual furnace loading.
2. Lower Energy Consumption and High Thermal Efficiency: Fully continuous pyrolysis processes allow for the recovery of synthetic gas (syngas), which can be fed back to heat the reactor. This high level of self-supplied heat reduces energy consumption per unit of processed material.
3. Consistent Product Quality: With precise, continuous control over temperature and residence time, the composition of the pyrolysis oil remains stable. This makes it easier to obtain sustainability certifications for raw materials, such as ISCC or ISCC-PLUS.
4. High Degree of Automation: Automated, sealed feeding and residue discharge minimize human exposure. Furthermore, the continuous and stable nature of the flue gas and oil-gas systems makes it easier to ensure that exhaust gas treatment consistently meets environmental standards.
5. Extended Equipment Lifespan: By avoiding frequent thermal shock and temperature fluctuations, the wear and tear on the furnace body and its lining are significantly reduced, keeping long-term operation and maintenance costs under control.

What Systems Comprise A Fully Continuous Pyrolysis Plant?

1. Automatic Feeding System

This system continuously conveys shredded and pre-treated plastic into the pyrolysis reactor, ensuring a stable feed rate while utilizing a sealed structure to minimize air ingress. A combination of material seals and airlocks excludes oxygen, maintaining an oxygen-free, slightly negative-pressure environment within the continuous pyrolysis reactor. Achieving stable, continuous feeding is a key technical challenge that distinguishes this process from batch-type pyrolysis.

2. Continuous Pyrolysis Reactor

The core component of a fully continuous pyrolysis plant. Through indirect heating, waste plastic undergoes thermal decomposition (pyrolysis) within a sealed, oxygen-deficient environment. The Fully Continuous Plastic Pyrolysis system is designed for self-sustaining heat supply, primarily using the generated syngas as fuel, with natural gas or diesel used only for initial startup and ignition.

3. Condensation System

This system cools the high-temperature pyrolysis vapors, separating condensable liquids from non-condensable gases.

4. Syngas Purification and Recycling System

After impurities are removed, the purified syngas is routed back to the heating furnace to serve as fuel.

5. Oil Collection System

This system collects and stores the pyrolysis oil, preparing it for subsequent upgrading, processing, or compliant utilization.

6. Continuous Discharge System

Solid residues remaining after pyrolysis are continuously removed via a sealed screw conveyor. This continuous, airtight discharge process includes rapid cooling to prevent re-ignition caused by oxygen exposure. The resulting carbonaceous residue can serve as a feedstock for recovered carbon black (rCB), with the entire process designed to prevent dust emissions.

7. Circulating Cooling Water System

This system provides cooling for the condensers and the residue discharge cooler through independent, indirect heat exchange. It minimizes direct contact between process water and oil/gas, thereby reducing wastewater generation.

8. Control & Environmental Protection System

This system monitors temperature, pressure, feed rates, gas flow, and equipment operational status. It also incorporates exhaust gas purification, pressure relief mechanisms, and safety interlock systems.