About Vanessa 

Vanessa Gutiérrez is a Materials Engineer, specialised in polymeric materials, with more than 15 years of experience in the design and formulation of plastic materials for any type of application, incorporating additives and fillers through compounding processes. She is currently a Researcher in the AIMPLAS Mechanical Recycling Group. Her current lines of work are up-cycling of recycled plastics, decontamination, as well as studies and evaluations of the recyclability of packaging and other products. She has participated as a technical coordinator and in the research team in multiple projects at regional, national, and international levels.

About Aimplas

AIMPLAS is a technological centre specialised in plastic materials who for more than 30 years have provided solutions to companies throughout the value chain, from raw material manufacturers to transformers and end-users. It offers services and expertise in the treatment of plastic materials, regardless of the industry. Through our highly qualified team, AIMPLAS assists in developing innovative products and materials with advanced or more sustainable properties.

What are the current limitations of mechanical recycling technology that require alternative approaches to be investigated?

The main limitations of mechanical recycling are related to specific waste streams, which may include multi-layer packaging made of incompatible materials, products that have been severely degraded either during use or due to exposure to the elements after incorrect disposal, such as marine litter, and of course, very dirty and mixed waste. These materials result in low-quality recycling or cannot be processed at all, as they contain elements such as cardboard or aluminium.

Another type of materials with increasing presence on the market are bioplastics, such as PLA and starch mixtures, which are currently sent for composting. These materials can potentially be recycled, as they are thermoplastic materials, easily reprocessed. However, current infrastructures for both separation and recycling plants do not take these materials into account, mainly due to their volume, and they are often discarded, losing valuable raw material.

As chemical recycling technologies are still relatively new and many plants are still under construction, is the European chemical recycling industry currently equipped to capture those waste streams that are not dealt with by mechanical recycling?

Not yet. Nevertheless, chemical recycling is a reality. There are still many developments to be made and many plants to be built. The industry still needs to evolve and if legislation and regulations allow, the necessary investments will be made to reach the desired level that allows for solutions to all flows. But as with mechanical recycling, it is necessary to continue working on the proper collection and separation of waste that allows for the appropriate quantity and homogeneity of waste.

Chemical recycling is often a controversial topic, what are the main concerns surrounding chemical recycling technology and how worried should industry and the public be with these?

Chemical recycling should be a complementary solution to mechanical recycling. It should treat flows that cannot be treated by mechanical recycling, such as highly mixed waste, highly degraded waste, thermosetting waste, or that, although they can be treated, do not achieve the desired quality and safety, for example, food contact or textile applications. Given this, the main concern is that streams perfectly suitable for mechanical recycling are diverted to chemical recycling due to price issues or to take advantage of the production capacities of the plants, thus obtaining a recycled material with a greater environmental and economic impact than with mechanical recycling.

Establishing a series of legislative guidelines, evaluating the true environmental impacts and continuing to work on innovation and research should allow us to advance with the different types of recycling to achieve optimal solutions in each case, giving a good response to society and achieving true sustainability.

What other advances in collection, sorting, and pre-treatment are needed to optimise both mechanical and chemical recycling?

One of the main advances needed to improve recycling in the pretreatment phases is product marking systems, which go hand in hand with having an adequate infrastructure for this. In this case, these can be visible or invisible markers that allow users, machines or AI to identify the composition of the product, and if a specific sorting or recycling process is required, to be able to recover it correctly.

This type of marking and selection system can be very useful in technical plastics, such as those used in automotive parts or in the electrical-electronic sector, where there is a wide variety of compositions, generally being materials with high added value, such as composites with fibres and flame retardant additives. These materials could be recovered both mechanically and chemically.

Another advance could focus on adhesives and debonding layers, to be able to separate multilayer materials during conventional washing processes, or through recycling with solvents.

Vanessa Gutiérrez will be speaking on Day 2 at the Plastics Recycling World Expo Theatre.