Recycling: Thinking in Material Cycles

Author: Michael Vogel

Dec 21, 2022 Sustainability

The EU Commission intends to tighten the requirements for vehicle recycling. And electromobility will bring even more changes – despite cars already being the most recycled product in the world.

Cars are long-lasting products. They are often used for more than 20 years, albeit by different owners. But the end does come at some point – and then it turns into a matter of disposal. Here, too, cars stand out in a positive way: They are the most recycled consumer product in the world. According to market research company Transparency Market Research, recycling rates are particularly high in Europe and North America, while awareness in emerging markets in the Asia-Pacific region has only recently begun to increase. Based on vehicle weight, the global average recycling rate lies at 80 percent.
Strict recycling quotas in the EU
Since 2015, at least 95 weight-percent of an average vehicle must be reused or recycled in the EU. The latter can also be done energetically: burning it generates heat or electricity. 85 weight-percent must even be reused or materially recovered, i.e. recycled. According to statistics authority Eurostat, the ratio in 2019 – more recent figures are not available – was 89.6 percent on average across EU countries. This figure includes 6.1 million vehicles from the 27 EU countries as well as Iceland, Norway, and Liechtenstein. Some end-of-life vehicles are illegally declared as used cars and shipped to countries outside the EU, where they are recycled under poor environmental and safety standards. The figures on how many vehicles take this route vary widely depending on the source. The Heinrich Böll Foundation’s Brussels office estimates about four million vehicles.
The certified recycling industry takes a multi-step approach to dismantling end-of-life vehicles. First, they remove components in good condition and return them to the market after reconditioning and testing. This tends to be more important in the US than in Europe. All fluids such as fuel, coolant and refrigerant, oils, and brake fluid are also drained. Once the vehicle is stripped, it goes through the press and then through the shredder.
What remains are pieces about the size of a fist, which are then mechanically separated according to materials, using various processes over several steps. They are sorted into metals, plastics, and residual materials, and in some cases further differentiated into subgroups, such as magnetic metals. This subgroup includes steels, which are then returned to the steel production cycle. According to the US Environmental Protection Agency, the production of steel from scrap steel requires almost three quarters less energy than producing steel from iron ore.
Heterogeneous recycling industry
The vehicle recycling industry is very heterogeneous. Everything from numerous smaller companies to globally active corporations can be found. The names of most companies are not well known, but there are exceptions: Volkswagen and Toyota are also active in the recycling business. Electromobility will bring further changes to market participants. For example, Mercedes-Benz plans to start recycling high-voltage batteries in 2023. The recovery and recycling of lithium and other battery metals such as nickel or cobalt will be decisive for the sustainability balance of electric cars. And it is a similar situation for the power electronics installed in electric cars: The Eco-Institute estimates the recoverable metal quantities from one million electric vehicles at seven tons of tin, 85 kilograms of gold, 300 kilograms of silver, 17 kilograms of palladium, and 70 tons of copper.
More sustainable vehicles require more recycling in order to close the material cycles. So it is no wonder that market research firm Imarc Group expects this global market to grow by five percent per year by 2026. In 2020, it had a volume of 20.6 billion US dollars. European plans under the Green Deal are fueling this growth as well. The EU Commission intends to tighten the specifications for recycling. For example, the 40 or so different types of plastics found in vehicles will have to be made more recyclable.
In search of new energy-efficient separation processes
Plastics help make vehicles lighter and thus more energy efficient. Bumpers, seat cushions, dashboards, door panels, cable sheathing, and seals are made of plastics. They account for 150 to 200 kilograms of a vehicle’s weight. This incomplete list illustrates the wide range of applications for plastics. Up to now, they have mainly been recycled for energy. A number of research projects are underway for high-quality secondary recycling, ideally back into cars. The goal is to develop new economical and energy-efficient separation processes.
Fiber composites are a particular headache as well. These are plastics reinforced with carbon fibers. CFRP replaces load-bearing and safety-relevant steel parts, resulting in significant weight savings. Even if the role of CFRPs in automotive construction is not growing as rapidly as once assumed, the recycling problem remains virulent. At present, CFRP can only be recycled for energy, because the components are difficult to separate. It also requires special equipment, or carcinogenic particles could remain.
Now the automotive industry wants to start thinking about reuse and recycling as early on as the design stage of new vehicles. This has already led to the first components made entirely from recycled plastics taken from end-of-life vehicles. In addition, internationally standardized instructions for disassembling modules have been created to make it easier for recyclers. At last year’s IAA Mobility, BMW showed the BMW i Vision Circular, a design study made from 100 percent end-of-life materials and renewable resources. However, many more vehicles will end their lives in the shredder before this type of vehicle goes into series production.
“Life Cycle Analyses Reveal Weak Points”
DEKRA supports customers on their way to sustainability with critical reviews, certifications, and verifications. When it comes to the life cycle analyses of products in particular, recycling is always a key topic. Three questions for Christina Bocher, Sustainability Expert and Business Line Manager Sustainability in the Consulting Service Division.
Where do you see additional possible adjustments for vehicle recycling?
Bocher: With shredder residue, i.e. the materials that remain after the vehicle has been dismantled, recycled, and crushed. The trend toward lightweight construction is changing the already heterogeneous composition, as lightweight materials such as polymers or aluminum are increasing. There’s also still potential when it comes to the many different types of plastics. The challenge here lies in material separation in order to achieve grade purity. In addition, electromobility makes the recycling of battery materials relevant.
Can too much recycling degrade a product’s life cycle analysis?
Bocher: Recycling always has an environmental impact. Depending on the technology, a recycling process can be more or less efficient and energy-intensive. It also depends on the material. In some cases, thermal recovery can on balance be more sustainable than material recycling. For a product’s life cycle analysis, it also depends on whether the recycled materials remain in the material cycle or are used in a different one, usually for lower-value products. To illustrate using the PET bottle as an example: If recycled PET is used to make fibers for garments, this PET is missing in its own system, and thus in the production of new bottles. This would degrade the entire PET bottle’s life cycle analysis.
What can and can’t you learn from life cycle analyses?
Bocher: They enable products to be evaluated in terms of their environmental impact, and to reveal weak points. The entire life cycle must be considered consistently from start to finish. However, life cycle analyses are always a compromise. Ultimately, you’re creating a model and making simplified assumptions about reality. In the end, you must weigh up whether or not product development improves the carbon footprint at the expense of water quality or biodiversity, for example. The boundaries of the system under consideration are critical. That’s why it’s also so important to very precisely formulate the questions underlying a life cycle analysis.