What is rPET plastic?

A look at the beverage industry’s more sustainable alternative to virgin PET
Society’s approach to waste management and recycling has evolved considerably over the years, with a greater focus on sustainability, a circular economy and recyclable materials. Plastic drinks bottles are a key example, with recent years seeing a particular focus on using more sustainable materials for these containers, such as rPET plastic.

Understanding PET and rPET plastic

To understand what rPET is, we must first understand PET (polyethylene terephthalate), the material from which rPET originates.

PET, alongside HDPE (high-density polyethylene), is one of the most common materials for making plastic drink containers. The versatility and durability of the material also make it a popular choice for a range of other uses too, particularly in packaging.

PET is produced using petroleum, a fossil fuel, and requires a quarter of a liter of oil to manufacture just one single-liter bottle from virgin plastic. When you consider that more than a million plastic bottles are sold every minute, vast amounts of oil are needed to keep up with demand.

Image of bottles in a circle

rPET, on the other hand, is recycled PET. It is PET that has already been used at least once, recycled, and put back into use. As such, it represents a more sustainable replacement for the raw materials of virgin PET in the production of new beverage containers. Compared with virgin PET, rPET has a smaller carbon footprint and 79% fewer greenhouse emissions.

At a minimum, a single PET bottle can be recycled seven times, but the ability to decontaminate means this can be done ten or twenty times – maybe even more.

Rising demand for rPET plastic

Net demand for PET in the European Union (with its 27 member states) and UK was estimated at 5.1 million tons in 2020 – where 3 million tons came from virgin PET production, 0.8 million tons from imports, and 1.3 million tons from rPET production. Data shows a slight shift away from virgin production and imports, towards rPET production – with a 3.8% increase from rPET production, and a 2.7% fall in the supply virgin PET production.

Approximately 54% of all PET products are beverage bottles. An estimated 3.6 million tons of PET bottles were put on the market in the EU27+UK in 2020, an almost 6% increase compared to 2018.

Demand for food-grade rPET (that is, that the materials of the bottle will touch food or drink to be ingested) for bottle production is actually exceeding the supply. There would need to be an expansion in recycling capacity of this grade (such as through advanced mechanical recycling) as well as an increase in the supply of collected PET bottles of sufficient quality in order to feed this capacity.

Creating food-grade rPET plastic

If rPET is used to produce drink bottles, it's essential that it complies with the standards for food-grade contact. Here, strict standards and procedures cover every part of the process, from the handling of the PET bottles that are to be recycled, to the maintenance of the machinery that will grind and shred them ready to be turned into rPET.

To create that beautiful circular economy loop when producing rPET, in the European Union we need to ensure that no more than 5% of non-food contact materials enter the process. And, we need to ensure the PET plastic bottles we recycle are in the best possible condition before they even enter the bottle grinder.”

Image of Frédéric Durand
Frédéric Durand Head of TOMRA Sorting in France

“We have a responsibility to take out impurities," he continues. "The label is a contaminant. The cap is a contaminant, though this can be sorted away by polymer type. We must also pre-wash the bottles, not only to eliminate the remnants of whatever drink they contained, but also to ensure there is nothing abrasive on them, such as sand or even dust. These have the potential to blunt the blades of the grinder very quickly. Then there’s the grinder itself: we need to be sure the blades are working well, and that there is no damage, because ultimately we want as much consistency as possible in the grain size and distribution.”

How is rPET plastic made?

The process begins with the bottles being sorted, washed and dried and labels removed, ready to be turned into plastic flakes. They are ground, sieved and sorted before they undergo their first quality control check. The more accurately the materials are sorted at a pre-sorting and flake sorting stage, the cleaner the material streams created (for example, sorting into light blue PET). The latest sorting technologies enable this separation and contribute to the quality of the recyclates.

Image of rPET plastic flakes
Image of plastic flakes in sorter

Once this initial step is complete, those flakes can have a number of uses. The preferred option for these flakes is bottle-to-bottle recycling. Other uses include fibers, tray, carpets or other products, but using the bottles’ flakes for a different application is "downcycling", meaning recycling the materials into a product that cannot be easily recycled, so that those materials leave the loop of resource reuse. If the intention is to produce drink bottles and achieve closed-loop recycling, there are two more key phases.

In phase two, rPET plastic production begins. In a process known as “amorphous granulated extrusion”, small plastic cylindrical pellets are made, measuring 2mm by 6mm. (This phase is typically only for packaging like trays and bottles, or in a few cases fibers.)

The final stage involves increasing the viscosity of the material to ensure it is suitable for its intended use. For example, bottles produced for still water will require a different density than those produced for fizzy drinks – the latter needs storage suitable for the higher pressure that comes from the carbonation.

This part of the process, and final decontamination, takes place in a vacuum reactor over a seven-hour period at 200 degrees Celsius.

Deposit return schemes’ role in rPET plastic production

A deposit return scheme (DRS), also known as a deposit return system or container deposit scheme, is a way of incentivizing the return of drink containers by charging a small deposit when a drink is purchased, which is refunded when the container is brought back for recycling. DRSs are typically introduced through government legislation, and there are currently around 40 regions across the globe operating such systems.

Image of couple looking at beverages

Collecting materials through a deposit return system can have a number of benefits. First and foremost, a DRS can help deliver a steady supply of PET materials to help keep up with a growing global demand for rPET.

TOMRA examined the impacts of high-performing deposit return systems, highlighting their ability to achieve collection rates of more than 90%. When 100 virgin PET bottles are produced, 90 out of those 100 bottles are collected and 208 new bottles can be made with recycled content (assuming a recycling rate of 75% of all PET beverage containers in a closed-loop system with multiple renewal cycles). By comparison, in non-deposit markets, for every 100 virgin PET bottles produced, 49 were collected and only 60 new bottles were made with recycled content.

Another advantage of a DRS is that the materials tend to be cleaner and higher quality because they are collected separately, avoiding impurities from other types of waste that could make them more complex or costly to recycle. Frédéric Durant explained that the materials lost due to impurities when PET is collected through a deposit return system can be as low as 5-6%.

This minimal contamination also means that materials collected and processed through a deposit return system (when compared with curbside collection) have greater value – PET post-consumer bales collected in this way are worth an estimated 40% more than those collected through curbside systems.

Encouraging use of recycled content

Establishing recycled content minimums for PET would send a signal to the markets that demand for recycled material will be consistent, which would help to stabilize its value. A number of markets have introduced directives setting targets for including recycled content in PET bottles.

In the European Union, the Single-Use Plastics Directive incorporates recycled content mandates for plastic beverage containers, setting a 25% target for recycled content in PET bottles by 2025 and 30% for all plastic bottles by 2030.

Illustration of Single-Use Plastics Directive targets

In California, an ambitious recycled content law sets a target for plastic beverage containers subject to a deposit to include 15% recycled content by 2022, 25% by 2025 and 50% by 2030.

A growing appetite for rPET plastic

We only have to look to some of the world’s biggest brands to understand the growing importance of, and appetite for, rPET.

Water bottles produced by UK-Based water brand Buxton (a Nestle subsidiary) are now entirely made from rPET, and Nestlé Waters UK recently told BBC Radio 4 that the move to rPET is contributing to reducing carbon emissions across the supply chain.

Meanwhile Coca-Cola announced its bottled water Dansai, which is sold in the US and Canada, is being rolled out in 100% rPET bottles this summer. PepsiCo is another brand to have set out rPET commitments, aiming to switching its UK ready-to-drink bottles to 100% rPET plastic by the end of 2022.

Protecting valuable resources

“Naturally, businesses will want to buy materials at the lowest price and they also need to ensure they have a steady supply of their materials of choice. But beverage producers are increasingly aware that their consumers and their investors are more environmentally conscious than ever and, without a doubt, this will play a role in influencing their approach,” explains Frédéric Durand from TOMRA.

“If we want to save the resources of the planet, we need to use what we have produced. PET is a material that truly allows this circular economy, with the potential to be recycled again and again: to make bottles into bottles, trays into trays, and fiber into fiber, as much as we can. When PET bottles are turned into fibers, carpets and other applications, the PET material can no longer be recycled easily; it leaves the loop. Achieving circularity on fibers and trays will also reduce the demand to use PET bottles for these applications. PET bottles can be recycled into new bottles in a continuous loop, over and over. To make this possible on the biggest scale, we need to increase our collection rate, and increase the quality of what we collect.”