Sustainability trifecta: Bridgestone, BB&G, Versalis keep ELTs in the loop

BRUSSELS—Material changes for the sake of sustainability can require extensive collaborations, and the circular use of tire pyrolysis oil in tire manufacturing is no exception.

For close to three years, Bridgestone EMEA; Fatima, Portugal-based Grupo BB&G; and Milan-based Versalis have worked to establish one such partnership, creating a closed-loop ecosystem for recycling ELTs.

The three organizations signed an agreement to establish the partnership Sept. 2.

"The collaboration is the result of two to three years of work which has involved extensive market scouting and a comprehensive end-to-end project scoping exercises to get to the precise terms of the initiative we're announcing," Marco Musaio, head of end-of-life tire and circular economy, Bridgestone EMEA, told Rubber News. "The three parties have some previous experience of development work together and each bring world class expertise in their field to the project, ensuring the best possible skills and competencies for every stage of the circular ecosystem."

In many ways, the discussion of ELTs as a feedstock for pyrolysis technology has focused on recovered carbon black as the reusable product.

And in many ways, the discussion should be equally focused on the recovered oil—the vastly more circular of the two pyrolysis end-products.

While rCB is rarely a one-for-one, drop-in replacement for virgin CB, TPO can be polymerized for use back into tire manufacturing—with no loss in safety or performance parameters.

"We do not anticipate any difference between fossil-based and TPO-based polymer; consequently we don't anticipate any differences in tire performance," Musaio said.

According to Bridgestone, feedstock ELTs will be pyrolyzed by BB&G, which has a commercial tire pyrolysis plant in Fatima that became operational July 24.

"This strategic partnership with industry leaders Bridgestone and Versalis is a huge step toward achieving our visionary goal of accelerating tire recycling worldwide," BB&G CEO Germano Carreira said. "It confirms the value of our patented technology and acknowledges the persistence that has brought us to this crucial point, enabling us to expand our technology across different regions.

"This collaboration is not just about advancing our products—it is a joint effort to increase circularity in the industry, aligning with global sustainability goals."

From BB&G, the captured TPO will be sent to Versalis in San Donato Milanese, which will convert it into "circular elastomers that Bridgestone will use to create a first batch of tires in early 2025," according to the world's second-largest tire maker.

"In line with our strategy for circularity, we have developed lower carbon solutions which perfectly fit in the value chain we've established with our industry partners Bridgestone EMEA and Grupo BB&G," Versalis CEO Adriano Alfani said. "This agreement aims at delivering maximum value to our customers and an innovative boost to the tire industry, furthering our commitment toward a more sustainable mobility."

For its part, Versalis, a subsidiary of the major Italian chemical firm Eni, also is looking to diversify its feedstock, using both renewable sources and secondary raw materials.

Through the partnership, Versalis will look to integrate BB&G's TPO into its own Balance portfolio, an ISCC Plus-certified product range.

"Versalis offers a broad range of complementary solutions that include products from recycled plastics as well as from bio-based feedstocks," a Versalis representative told Rubber News. "This approach aligns with our broader strategy of integrating innovative technology platforms and collaborative partnerships within the supply chain to achieve long-term sustainability goals."

This project announcement relates solely to the TPO produced from the pyrolysis of ELTs, not rCB.

Bridgestone also is engaged, separately, in an initiative with Michelin to promote material circularity in the tire industry, in this instance with a specific focus on increasing the use of rCB in tires.

Using feedstock ELTs from the Iberian peninsula region, ELT granulates will be sent to BB&G's pilot plant in Portugal via an industrial tire recycler in that market.

BB&G uses a thermo-mechanical pyrolysis process (high heat in the absence of oxygen) to break down the ELT granulate compounds and produce a quality TPO.

"In the first instance, BB&G has already secured sufficient ELT feedstock for the pilot phase of the project via a supply agreement with industrial recyclers operating in Portugal," Carreira told Rubber News. "As the project evolves, similar feedstock supply agreements will be sourced in other locations."

In turn, Versalis will use the TPO to produce new monomers (using its own proprietary process), which will be used to create elastomers with the same properties as virgin ones.

"This process will take place within Versalis' production chain, which is fully certified by ISCC Plus," Versalis said. "By integrating TPO into their production, Versalis ensures that the resulting elastomers are circularly attributed, maintaining high quality and sustainability standards. This approach not only supports environmental goals but also meets the stringent requirements of their clients."

These elastomers then can be used by Bridgestone on the back end as raw material for new tires.

"Bridgestone does not receive the tire pyrolysis oil directly; rather it is able to use the TPO-based polymers produced by Versalis as one component in the manufacture of new tires," Musaio said.

In an initial stage, BB&G will produce around 600 tons per year of TPO in the commercial unit based in Portugal.

"Nevertheless, in a second phase within two years at industrial scale, higher amounts of TPO—in the order of 5,000 tons per year or more—will be accessible to be used as feedstock to Versalis' steam-cracking units," Carreira said.

BB&G, founded in 2013 in the U.S., has reached a commercially scalable level for TPO, a difficult accomplishment in a space that sees many startups dotting the pyrolysis landscape.

In 2015, BB&G built an initial pilot plant, also in the U.S., dedicated to the production of TPO. As it turned out, the initial rCB (or the solid pyrolysis end-product) "presented high levels of organic contamination and therefore minimum market value," Carreira said.

In 2018, BB&G continued its research and development in Portugal, focusing on strategic partnerships that led to construction of a second pilot unit.

This second unit focused on the production of both TPO and rCB, in this case presenting high quality for the latter. A third scale-up was designed, leading to the construction of the commercial plant in Fatima, according to Carreira.

"What probably makes BB&G successful compared to others is our intensive R&D over the last 10 years that have allowed us to mitigate the scale-up risks," Carreira said. "We have ensured an excellent process with conditions that allow good quality results in both TPO and rCB in a continuous system.

"Moreover, BB&G was also able to achieve steady feedstock allowing consistent quality products."

Unique to BB&G's process, Carreira said, is a multi-stage reactor where both temperature and residence time can be independently adjusted, determining the high quality of end products.

BB&G has added ISCC Plus certification for greenhouse gas emissions for both rCB and TPO.

BB&G's technology is certified to emit 238 kg of CO2 per ton of rCB and 484 kg of CO2 per ton of TPO, compared to an average of 2,600 kg of CO2 per ton emitted in the production of furnace CB and fossil fuel oil.

Like other major tire manufacturers, Bridgestone is eyeing that 100-percent sustainable tire.

Outside of TPO and rCB, other alternative, more sustainable tire ingredient possibilities include latex from dandelions and the guayule plant, and silica from rice husk, among many other considerations.

"Indeed, Bridgestone is on a journey toward 100-percent sustainable materials," Musaio said. "It will not happen overnight, but we have multiple initiatives which will collectively contribute to that goal.

"In terms of recycled materials, we're working with various partners around the world to accelerate the collection of used tires and introduce various recycling technologies."

As previously stated, one such initiative in conjunction with Michelin is focused on rCB production from ELTs.

"And of course, recycling is just one element of this journey," Musaio said. "In addition, we are working to ensure the sustainable production of our key raw material, natural rubber, as well as exploring options to diversify renewable materials.

"Guayule is one such example of that—we're investing heavily in research and development of this natural rubber alternative which can be grown in arid zones, aiming for commercialization around 2030 through innovation and bio-technology."

And partnerships, like the collaboration for TPO between Bridgestone, BB&G and Versalis, are critical to advancing these initiatives.

"We are committed to collaboration and co-creation with various partners around the world, not only to valorize ELTs but also to support renewable sources," Musaio said. "In terms of recycled materials specifically, this ecosystem announcement in EMEA is just one of multiple initiatives we are engaged in around the world.

"Establishing a more sustainable, circular business model in our industry and indeed across the business world, is technically challenging and requires innovation and collaboration and this is why it is therefore necessary to work with various partners to explore different routes."