Nobody likes to think about tires because they’re not drool-worthy, but tires are the reason for every drool-worthy performance-related stat posted by any vehicle. The global vehicle market is estimated to demand about 2.7 billion new tires in 2022, part of which goes to replace the roughly 1 billion tires that end their lives every year. Those are enormous numbers with enormous implications, tires estimated to shed 2 million tons of tread particles each year in the U.S. alone. These are part of the non-exhaust emissions of a vehicle, and in 2019 a UK government Air Quality Expert Group found these microplastics could pollute 1,000 times worse than vehicle exhaust. Bridgestone and Michelin have formed a partnership that could help reduce such numbers by finding ways to recycle carbon black, a key part of tire manufacturing.
The Birla Carbon blog describes carbon black as a “vital component in making many of the products we use every day stronger, deeper in color and longer lasting.” It’s different from black carbon, which is the soot created by burning items like wood, coal, diesel, and dung. The primary use of carbon black is to make tires stronger, as a thermal conductor, and as a filler throughout the tire layers. Bridgestone and Michelin say that even though the process of recycling and recovering materials from discarded tires is understood, less than 1% of carbon black used in the billions of tires made every year comes from recycling. The two companies want to lead the development of a supply pipeline that would raise that figure, which could be huge, the companies saying that using recycled carbon black lowers the CO2 emissions of new tired production by 85%. That’s for just one ingredient of the tire, one that a Continental Tire video shows requires high refinement to create from base feedstocks, a Birla Carbon video going into even more detail of the intense energy demands.
The Japanese and French partnership gave a talk at the Smithers Recovered Carbon Black Conference in Amsterdam — yes, this issue is big enough to have its own conference, which has been going on for years. Michelin VP Sander Vermeulen said, “For years discussions have been ongoing about the different constraints and hurdles that were preventing the rubber industry to adopt recycled and or recovered raw materials in significant quantities. We felt it was the time to stop discussing and actively contribute to finding solutions that would enable the rubber industry as a whole to become more circular by increasing its ability to adopt recycled and or recovered materials from end-of-life tires.”
Next year there will be a position paper outlining technical requirements and proposed solutions for the industry to attain a circular, sustainable economy in recycled carbon black. They’re looking for more tire-making partners, too, enough to generate the critical momentum necessary to significantly lower the emissions and pollution figures.