A tyre's life cycle and recycling
Life cycle refers to the different stages a product undergoes from manufacture to use and, ultimately, recycling. The life cycle of a tyre begins from a rubber tree in the southern hemisphere, for example in Indonesia or Thailand. It spans the manufacture of raw materials and products, storage and several rounds of transportation. The tyre’s actual life cycle ends, for instance, when the tyre is crushed and used as a construction material.
The life cycle can be roughly divided into four parts:
- Purchasing and manufacture of production inputs such as raw materials and energy
- Tyre manufacture
- Use of tyre
- Utilisation of used tyres.
The outset for our environmental protection is the life cycle approach. This means that we take responsibility for the environmental impacts of our operation and our products throughout their life cycle. In accordance with our purchasing policy, our product procurement process includes determining the suppliers’ commitment to the environmental aspects. In 2016, 67% of our raw material suppliers had the ISO14001 certification. All contract partners, such as contractors and subcontractors, must be committed to Nokian Tyres’ principles.
Most of a tyre’s environmental impacts are generated during use. The single most important factor is the vehicle’s fuel consumption. Fuel consumption can be decreased by reducing the tyre’s weight and rolling resistance, thereby cutting the exhaust gas emissions and the formation of greenhouse gases. However, the most significant factor affecting the level of exhaust gas emissions is the driving style. Economic driving can generate 10–20% savings in fuel consumption.
The most significant life-cycle environmental impacts of a tyre are caused by the vehicle’s fuel consumption, which also generates emissions into air. The following graph presents the environmental impacts of a tyre as the carbon footprint.
Further studies are needed about the possible impact of micro polymers
Lately, there has been discussion about the microplastics that are ending up in seas, and motor vehicles have been brought up as one of the sources. Regarding tyres, the term “microplastics” is somewhat misleading because tyres contain rubber rather than plastic. However, plastic and rubber are both polymers. Tyre wear generates tyre dust, and many publications have included it under micropolymers or microplastics.
The current research indicates that rubber particles that enter bodies of water do not pose verifiable harm to the ecosystem or human health. However, we need more of reliable research results, and microplastics’ potential impact on aquatic ecosystems and human health should be thoroughly investigated. We are actively following the studies on this topic and we participate in external studies ordered by ETRMA and other organisations. Furthermore, we have looked into the utilisation of various bio-based materials in our products.
Our company is committed to continuous improvement, and we are developing our products and our functions to be even more eco-friendly. We take human safety and health very seriously. If, in the future, new research suggests that micropolymers are harmful, we will react and look for new solutions. The materials that are used in a tyre must be considered from the perspectives of safety and eco-friendliness.
One important aspect of reducing the harmful impacts of driving is how we can prevent particle emissions from traffic or control them in an eco-friendlier way from the infrastructure perspective. Such areas for improvement could include sewer systems, ditch embankments or water purification.
Retreading offers eco-friendly driving
The Nokian Noktop retreading complements our service offer and brings cost savings and eco-friendlier kilometres to professional driving. Tyre retreading allows the operator to save money, resources and the environment. A good tyre carcass can easily be retreaded two times, which cuts tyre costs by approximately 30%.
CO2 emissions are generated during tyre production as well as driving. Retreading has a significant impact on the carbon footprint of tyres: manufacturing a new tyre results in approximately 220 kg of CO2 emissions, whereas the figure for retreading is only approximately 40 kg. Furthermore, each retreading operation saves 40 kg of rubber and 70 litres of oil per tyre compared to new tyres. Our new Nokian E-tread product family provides even higher raw material and energy savings. As a result of our product development efforts, we are able to recycle our tyres’ excellent rubber compound even more efficiently without compromising on quality.
Our winter tyres for trucks and buses and our Noktop retreading materials use a Cap/Base structure, which is optimised for the seasons in the north. Its tread is composed of two layers. When a tyre is fitted in the autumn, the softer top layer (Cap) provides winter grip. The top layer will wear out by the spring, revealing the harder rubber compound (Base), which ensures that the tyre provides sturdy performance in the following summer.
Where do tyres end up after use?
Approximately 3.2 million tonnes of used tyres are discarded each year in Europe. Luckily for the environment, discarded tyres are not worthless and can serve various reuse or recycling applications. They can be used, for instance, in noise barriers along motorways or as an elastic base material in horse riding arenas.
If tyres are not appropriately recycled, they will end up in the environment or pile up in people’s garages. The recycling rate of tyres in Finland is high compared to many other countries. In 1995, Nokian Tyres and other companies in the tyre industry established the Finnish Tyre Recycling Ltd in order to promote the centralised collection and utilisation of tyres nationally. In Finland, close to 100% of tyres are recycled. In all of Europe, for example, 95% of tyres are recycled and non-recycled tyres are taken to landfills. In Russia, the tyre recycling rate is low. According to new legislation, the share of tyres recycled in Russia must be, at a minimum, equivalent to 15% of the total sales in Russia.
Most of the recycled tyres are utilised for their material; they are shredded or granulated to replace rock materials in various road construction and civil engineering applications. Retreading tyres is one of the best recycling methods. If the carcass of a tyre is undamaged, it can be retreaded – bus and truck tyres up to two or even four times. It is also possible to combust tyres for energy, as the thermal value of tyres is close to that of oil. We are constantly looking for new ways to recycle and utilise tyres.