Turning plastic back into oil

The Dutch company PyrOil developed a method to turn plastic back into oil in a continuous stream using pyrolysis.

Pyrolysis is the thermal decomposition of materials, changing the chemical composition. It can be used on all kinds of materials, like in the process of charring wood. In the case of plastic, the material is heated to about 500 degrees Celsius (930 degrees Fahrenheit) without oxygen. The plastic turns first into liquid and then into gas, and this gas is led to a condenser. When the gas cools down, you’re left with liquid oil.

The process of turning plastic back into oil using pyrolysis is not new in itself. It has long since been known that this process can create clean, sulphur-free oil. However, the problem with the process was that until now, the oil had to made in batches. The machines have to be heated up, which takes a while, then the plastic is turned to oil, and then the machines have to cool down before new material can be added and everything can be heated up again. This, in turn, leads to material fatigue in the machinery. Therefore, pyrolysis has never been profitable and scalable.

PyrOil developed a method to continuously be able to add new plastic, without oxygen and without having to let the machines cool down in between. This way, they are able to scale up to an industrial level and create a closed cycle.

The process creates three products: sulphur-free oil, flammable gas, and ash. The newly produced oil is suitable as fuel and to make new plastics. The ashes are sold to asphalt and concrete producing companies. The flammable gas, finally, is used to heat the pyrolysis installation and to generate electricity. The whole process therefore generates nearly no emissions and waste.

After nine years of research, PyrOil has started the construction of their first industrial-scale installations in 2019. Over the next ten years, John Kuipers, the founder of PyrOil, plans to build 1000 factories all over the world.