Plastics: Towards a Circular Economy

Using chemical recycling to tackle the problem of plastics waste

WITH only 30% of plastics currently recycled in the EU and less than 10% worldwide, plastic waste represents an enormous challenge. Chemical recycling is one of the solutions that should be deployed to address this problem, and at Plastic Energy we have developed technologies to combat the growing threat of plastic pollution and to respond to the growing pressures to increase recycling and move towards a circular economy.

We use a patented technology, Thermal Anaerobic Conversion (TAC) to convert end-of-life plastic into hydrocarbon oils, known as TACOIL. This can then be used as a feedstock to create virgin-quality recycled plastics (closed-loop Plastic2Plastic) or alternative low-carbon fuels (open-loop Plastic2Oil).

While there are other companies developing chemical recycling, we are currently the only company commercially converting end-of-life plastic into the optimal feedstock to make new plastic. Based in the UK, we have two operational plants in Spain, in Seville and Almeria, and have announced plans to build in the Netherlands, Malaysia and Indonesia, but have other projects in the pipeline including in France and in the UK. We expect by 2023 to build the capacities for ten plants in Europe and ten in Asia.

Unrecyclable to food-grade

Our concept of chemical recycling is a technology targeted towards end-of-life plastic which can’t otherwise be mechanically recycled. End-of-life plastics are defined as plastics that are mixed, contaminated, multi-layered, as well as plastics that can no longer be mechanically recycled. This is the case especially for food-grade plastic packaging, especially films, wrappers, packets, tubs, and pots that represent complex packaging made of various polyolefins, and sometimes other layers such as metals or paper.

This means that chemical recycling complements mechanical recycling by diverting plastic away from landfill, incineration, being sent abroad or leaked to our environment.

The TACOIL we produce from end-of-life plastic is then used as a feedstock to create virgin-quality recycled plastics, Plastic2Plastic. In practical terms our process makes plastics traditionally considered as unrecyclable endlessly recyclable into high quality products.

It is also important to clarify that chemical recycling upgrades (often called ‘upcycling’) the plastic through the conversion into the original monomers in each process of recycling, making it eternally safe and reusable as a food-grade product.

As an example, we have an agreement with SABIC, which will process TACOIL (replacing virgin oil) into virgin-quality polymer granulates, certified by the ISCC, and then be supplied to key customers such as Unilever, Vinventions, or Walki Group to develop high quality, food-grade, packaging for food, beverage, personal and homecare products.

Food-grade packaging with recycled content is already now on the market. For instance, in October, Unilever put 600,000 Magnum tubs with recycled content onto the Spanish, Dutch, and Belgian markets. Tupperware Brands will also use the "certified circular polymers" to make two long-term sustainable products to help reduce the use of single-use plastic — including a reusable straw and coffee cup.

Patented technology

This technology started more than ten years ago. We progressed through the engineering research and design, the construction of two pilots in 2015 and 2017 (in Spain) running at first for a few days at a time, to running continuously and becoming commercial. These two plants are now processing 30 t/d of end-of-life plastics, 340 days a year with scheduled shutdowns for maintenance.

TAC is a low-pressure thermal depolymerisation process patented in Europe and the US.

The main sources of plastic converted are post-consumer plastic waste from municipalities representing a majority of low-density polythene (LDPE), high-density polythene (HDPE), polypropylene (PP), as well as some polystyrene (PS).  These are normally contaminated after mixing with other wastes.

After receiving the waste plastic, we pre-process it to remove non-desirable materials from the feedstock such as metals, textiles, paper, leftover PET and PVC. Although it is quite rare to see PVC in the post domestic waste, it has a negative impact on the chlorine level of the output, although it not the only source of chlorine. Polyethylene terephthalate (PET) is also non-desirable in our process as it adversely disrupts the TACOIL composition and properties. It is worth noting that PET also has an existing and mature recycling market and attracts a high trading price.

The pre-processed feedstock is then shredded, densified and melted. This homogenised molten plastic is pumped into the oxygen-free reactors at a controlled rate and temperature. To create a stable product, this step also requires precisely controlled heating and pressure in the various systems. The multicomponent hydrocarbon vapour produced in the reactor passes through the contactor vessel which finally controls the hydrocarbon chain length and quality before entering the condensation system.  The TACOIL is then subjected to additional purification and polishing steps before final storage.

Every ton of plastic processed produces 860 L of TACOIL – composed of naphtha and diesel.

Pioneering work

Our aim as a technology company is to align our research and development (R&D) with both commercial opportunities and improving the efficiency of the process.

We have conducted extensive input/output analysis over many years to determine how different types of plastic feedstock affect the process and the final output, which widens the range of feedstock we can accept.

We have been working over the past three years with various clients in the chemical industry to adjust our process to their own cracker requirements. This has involved understanding how best to manage contaminants – chlorine is one but there are many others (which we can’t mention here, for commercial reasons) – and create the optimal feedstock for each one of them.

Improving the performance and efficiency of the process and product is a continuous goal, including reducing the energy consumption, reusing the synthetic gas produced in the process, and transitioning towards sustainable sources of energy among many other ongoing projects. To do this, we are always exploring strategic collaboration with research institutes and commercial entities. 

Second generation

We have had fully operational, industrial, and commercialised plants running for more than three years, so the process is proven, and has enabled us to sign MoUs with large chemical and petrochemical companies for projects both in Europe and abroad for large-scale projects.

We can run the technology continuously, and our semi-batch process is suitable for scaleup, by adding new lines without adding technology risk or uncertainty.

We are therefore scaling up our new plants to process 20,000-25,000 t/y of plastic waste (previously 5,000 t/y). These next-generation plants will cost around €35m (US$39m) and will create around 30 direct jobs. 

We took the decision in 2018 to roll out assets and plants that we are going to develop, own, and operate. The plan is to build ten plants in Asia and ten in Europe by 2023. That will require €800m but will give us the capacity to process 500,000 t/y of plastics every year. That will then lead us to the point where we will be able to decide whether to continue developing, owning, and operating plants or to license the technology to different partners.

For each plant, our strategy is to work with one off-taker that will sign a long-term agreement to buy the entire TACOIL production – that will suit its own specifications.

The plants will be located either by the off-taker or by the feedstock provider. However, we do not support the construction of a unit in a waste management facility as we estimate that it could represent a safety risk. Chemical recycling is a chemical process that should be treated as such, with the necessary control, safety, and training of the personnel.

Challenges

Collaboration with the whole value chain is essential, as is supporting new solutions aiming at increasing recycling rates and creating a circular economy.

Industry is driven both by corporate commitments as well as regulations and targets established by governments and spearheaded by EU policies. For example the EU’s Circular Economy Package lays down ambitious targets, including that by 2030, all plastics packaging placed on the EU market is either reusable or can be recycled in a cost-effective manner.

Getting to where we are now has not been without its challenges, and we are still facing many more. We are a small company, while the need to develop better recycling solutions is huge. The challenge is for us is to remain focused, and wherever we are going to build a plant we need to work closely with the regulators to ensure a smooth deployment.

Because we are a relatively new industry, there are discussions about how to categorise our activity. Until recently it has, by default, been categorised as energy recovery in the EU Waste Hierarchy, but as the circular concept of Plastic2Plastic is now validated and certified by the ISCC and the industry, this process we believe should count in the recycling targets, something the Netherlands has already legislated.

We need harmonisation of regulations on chemical recycling across countries, but also efficient national systems to enable secure feedstock supply to divert plastic waste away from landfills, incineration, or exportation to countries with less infrastructure.

Given that chemical recycling requires large investments, we need clear regulations and incentives acknowledging its benefits, to allow further expansion. This is even more true in developing markets such as Indonesia where the development of chemical recycling will imply the prior construction of robust waste management and sorting facilities as well as an organised collection system.

Finally, if European countries build infrastructure to deal with their end-of-life plastic instead of exporting it to developing markets, it would lead to the improvement of waste management, the reduction of pollution, and the creation of a new industry and jobs in each country.