The PRISM model

This model makes it possible to create future scenarios concerning the circularity of plastics. Using this model, TNO has carried out an initial study into the maximum circular plastic system of 2050.

The foundation for this scenario is our forecast of the future composition of plastic waste, which is based on the market growth in the various relevant sectors (packaging, construction, mobility, electronics, etc.), the trends related to plastic application in these sectors and the recyclability of the applied plastics.  

The PRISM model then selects the desired recycling technologies for the different (mixtures of) polymers in order to achieve the desired goals in terms of (lifecycle) CO₂ emissions and material production (quantity and quality).

CIRCULAR PLASTIC SCENARIO

Our methodology differs from most other models because we assume that the collection and sorting of the plastic will be adapted accordingly. The maximum circular plastic scenario is exploratory rather than predictive and is shown in the box (together with the most important assumptions). Work is currently underway to extend the model to include costs so that economic factors can also be included in the scenarios.

FUTURE CIRCULAR ECONOMY SCENARIO FOR 2050

The maximum circular plastic scenario 2050 is illustrated by the Sankey diagram below.

The first column (left) indicates the various raw materials used by the chemical industry for the production of different polymers (second column). The third column contains the market segments of these polymers and the fourth and fifth columns indicate the methodology used to collect and sort these plastic products and to process them (recycled, reconditioned or incinerated).

The last column (on the far right) shows the circularity of the system: a total of 87% of plastic waste can be processed into new products (as input on the left); from the remaining 12%, the energy is recovered. This is dependent on the efficient adaptation of the collection and sorting system to the conditions of the recycling technologies used. 1% leaves the system as litter, including microplastics.

The most important assumptions, as input for the PRISM model, are:

• Plastic waste in the Netherlands will increase by 50% by 2050
• Plastics in different sectors have different lifespans, resulting in plastic waste in differing quantities
• Plastic products are reused or reconditioned as much as possible
• Sorting is optimal for all recycling techniques
• As a result of this, 50% less material will be lost during recycling
• Litter will be reduced to 50% of the current share or recovered efficiently
• Fossil raw materials will have been partially replaced by bio-based raw materials
• Nothing is being dumped anymore

TRANSITION TO A CIRCULAR PLASTICS ECONOMY

Our PRISM analysis of the plastics ecosystem shows that an accelerated transition from a linear to a circular plastics economy is technologically feasible up to about 87%. In addition to the obvious focus on technological developments in the field of sorting and recycling, requirements must also be met in order to complete this enormous task: firm policy, consumer acceptance and a sense of responsibility amongst producers and the entire value chain.

These have not been included in the analysis.