Turning plastic waste back into raw materials is important in the circular economy. This raw material must be safe for humans and the environment. Pyrolysis is a recycling method that is increasingly being applied to plastics. The oil produced in this process is a raw material for new plastics. The RIVM has investigated which Substances of Very High Concern (SVHCs) may be present in pyrolysis oil. This knowledge is important for safely applying the technique on a large scale. The RIVM recommends conducting more measurements of SVHCs Substances of Very High Concern (Substances of Very High Concern) in pyrolysis oil and sharing this data.
The Rise of Pyrolysis
Pyrolysis is a technique where (plastic) waste is heated without adding oxygen. The oil produced from this is a raw material for making new plastics. This chemical technique complements mechanical techniques such as shredding or melting. The technique is still under development.
Waste processors are increasingly applying the pyrolysis technique. This is related to European objectives to use recycled raw materials for new plastics. Which of these techniques contributes most to the goal of a circular economy has not been researched.
The RIVM previously published a study on the pyrolysis of tires.
From Waste to Raw Material
To produce pyrolysis oil for new plastics, plastic waste from households and businesses is currently the most suitable. According to the law, pyrolysis oil is still considered waste. To determine whether pyrolysis oil is no longer waste, it must meet safety requirements.
The RIVM compiled an overview based on scientific literature and interviews with stakeholders regarding which chemical substances may be present in plastic waste. It also investigated which Substances of Very High Concern (SVHCs Substances of Very High Concern (Substances of Very High Concern)) are expected in the pyrolysis oil.
Substances of Very High Concern Arise During the Pyrolysis Process
The research shows that there are Substances of Very High Concern (SVHCs) in plastic waste. Some of these SVHCs will be broken down during pyrolysis, but new SVHCs may also arise. The RIVM has created an overview of SVHCs expected to be present in pyrolysis oil. This overview may change as more measurement data becomes available.
The oil is post-treated to remove substances that may disrupt the production of new plastics, such as substances containing chlorine. This post-treatment is also important for removing SVHCs. What concentrations of SVHCs remain in the pyrolysis oil afterward is not known.
Recommendation
The RIVM conducted this research on behalf of the Directorate-General for Public Works and Water Management. The RIVM recommends that the Directorate-General for Public Works and Water Management include the list of expected SVHCs and the recommendation to measure them in the Guidance Document ‘End-of-waste for pyrolysis oil’. This guidance supports businesses and permit providers.