VIDEO: Smaller footprint: Vietnamese shoe-waste to be shredded into fuel

The production-waste from Vietnam's largest shoe factory will be converted into a fossil-fuel replacement thanks to a new partnership between shredding firm Untha and building materials firm Holcim.

Untha built an entire Solid Recovered Fuel (SRF) manufacturing plant in Austria to trial the new technology. Having achieved the standards required by Holcim, the plant was disassembled and shipped to Vietnam, where it is expected to be fully operational by September.

Untha’s technology is capable of converting 10 tonnes of material an hour into a useful fuel that will power Holcim’s local cement kiln calciner.

Christian Lanner, Untha’s head of engineering and product management, explained: “This footwear production waste is an incredibly difficult product to shred, due to the mixture of notoriously tough materials contained within sports shoes.

“We’re tackling rubber, textiles, plastics, metals, sponge, reinforcements and more. However, we extensively configured, re-engineered and trialled our flexible XR waste shredder – using the client’s own material – until it was perfectly suited to this application.

“We’ve also refined the cutting concept so that it is incredibly well equipped to deal with this demanding waste stream.”

The SRF plant in action:

Earlier this year Holcim merged with fellow construction giant Lafarge in a €41bn deal that analysts expect to improve the environmental impact of the two companies.

Investment analyst Sustainalytics said the deal could create synergies in energy and GHG performance, as well as improved positioning in the growing market for sustainable building materials.

While the idea of incorporating old shoes into the circular economy is not new, much of the work so far by companies such as Adidas, Marks and Spencer and Stella McCartney have focused on creating new shoes out of waste rather than vice-versa.

Brad Allen

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