CEO Mehran Zarrebini weaves the recycling thread for radial truck tyres

The Mathe Group recently announced that it had recycled one million waste radial truck tyres in KwaZulu-Natal, saving between 45,500 and 71,500 tons in CO₂ emissions since 2017.

ESG Global recently caught up with its CEO Dr Mehran Zarrebini, to ask him three clever questions about waste prevention, downstream impact and the company’s own operational carbon footprint.

While the reduction of CO₂ emissions through recycling is commendable, what are the long-term strategies in place to address the source of this hazardous waste stream? Specifically, addressing the question of evolving from waste management to waste prevention.

While recycling reduces the carbon footprint of end-of-life tyres (ELTs), long-term strategies must move upstream addressing the design, consumption, and regulation of tyres themselves. One key initiative is promoting design for environment principles, encouraging tyre manufacturers to create products with longer lifespans and greater recyclability and also tyres that utilise a percentage of recycled content so that they ultimately reduce dependency on virgin materials.

Concurrently, regulatory frameworks like Extended Producer Responsibility (EPR) schemes in Europe can shift accountability to manufacturers, incentivising tyre makers to limit production waste and invest in circular models. This evolution from reactive waste management to proactive waste prevention requires systemic collaboration between producers, recyclers, regulators, and consumers.

What are the downstream impacts of recycled material, when looking at the repurposing of rubber crumb for construction and industrial applications?

These span environmental benefits, infrastructure performance enhancement, health & safety improvements and circular economy and end-of-life considerations.

Environmental benefits cover:

• Landfill diversion: Reusing rubber crumb reduces the volume of waste tyres sent to landfill, significantly decreasing long-term environmental risks such as leachate contamination and fire hazards.
• Lower carbon footprint: Products made with recycled rubber typically have lower embodied carbon than those made from virgin materials like asphalt, concrete modifiers, or synthetic polymers.
• Energy efficiency: Rubber crumb-modified asphalts require less energy for production and maintenance due to improved flexibility and crack resistance, reducing lifecycle emissions.

Infrastructure performance enhancement is two-fold, looking at:

• Modified asphalt and roads: Rubberised asphalt offers superior performance enhanced skid resistance, noise reduction, and longer service life. This translates to fewer repairs and less frequent resurfacing, reducing resource demand over time.
• Shock absorption & vibration damping: In railways, bridges, and building foundations, rubber crumb improves shock absorption and structural integrity, particularly in vibration-sensitive zones.

With health and safety improvements, Rubber crumb is widely used in safety surfacing due to its cushioning effect, reducing injuries in high-impact areas like playgrounds and athletic tracks, and in buildings, rubber acoustic underlays and isolation pads derived from tyre waste help control noise, improving health outcomes in densely populated areas.

For circular economy and end-of-life considerations, there are second-use saturation risks: While rubber crumb markets are growing, they are not unlimited. Oversupply without diversification (e.g., advanced devulcanisation or pyrolysis) risks creating secondary waste streams. Continuous innovation is necessary to find new technologies that can deal with the increasing volume of waste tyres around the world.

In terms of leaching and microplastics, there are concerns about potential leaching of heavy metals or chemicals in certain applications, for example from synthetic turf. Regulation is essential to mitigate environmental risks. From our perspective, we perform toxicology and polycyclic aromatic hydrocarbon tests on the material that we supply to this industry to ensure that it meets stricture EU requirements even though there is little or no legislation in South Africa.

High energy consumption has been associated with the recycling process itself (shredding, processing, and transportation), what measures is Mathe Group implementing to minimise its operational carbon footprint?

Mathe Group has upgraded its processing lines with newer generation granulators and shredders designed for higher throughput and lower energy consumption per ton of rubber processed. This investment has resulted in measurable reductions in electricity usage across operational stages.

We have also integrated solar power into our facility operations, beginning with the installation of photovoltaic systems on all our building’s roofs. We currently have 980 solar panels installed generating up to 0.5MW of power. These solar arrays are already offsetting a substantial portion of our daytime energy consumption, with future plans to expand capacity and introduce battery storage.