Brussels – While end-of-life tire casings have traditionally taken centre stage at the BIR World Recycling Convention, the tires & rubber committee this year focused on recycling of other forms of scrap.
India-based GRP Ltd’s joint MD Harsh Gandhi, for one, outlined his company’s annual production of some 25,000 tonnes of reclaim from butyl inner tubes.
Around three-quarters of this material is sold back to the tire sector for use in inner tubes and tire linings at incorporation rates as high as 12-15%, the GRP boss told the 2 June online meeting.
Other applications include sound and vibration damping, said Gandhi, who estimated global butyl reclaim production at 200 kilotonnes/year – with South Korea, China and India as the largest producers.
For his part, Martin von Wolfersdorff, director of Wolfersdorff Consulting in Germany, reported that butyl reclaim volumes in Europe were far lower than those in Asia.
According to von Wolfersdorff, this European reluctance was despite the fact that this “very pure stream [offered] opportunities to recycle rather than downcycle.”
On a different front, Malaysia-based Bridge Fields Resources (BFR) has, since 2004, been converting a wide range of rubber scrap into high-quality gum, with major feedstocks including latex gloves.
As explained by chief executive Asmipudin Mohd Ali Jinnah, this pure-stream, single-polymer-structure approach offers “manoeuvrability” in terms of product options.
Applications include shoes, rubber bands, castor wheels and retread tires, said the BFR leaders, noting that: “Some manufacturers are willing to pay more if they can put it on their labels as ‘recycled’.”
The BIR meeting also addressed issues around the main technologies for recycling rubber, namely ambient and cryogenic micronisation and reclaim/devulcanisation.
According to Gandhi, many companies preferred reclaim to micronised rubber powder because of the former’s more elastomeric state.
“I think reclaim is here to stay longer because it is more active while crumb rubber is more inert,” he contended.
“In the end,” said Von Wolfersdorff, “it’s all about application performance and how much [recyclate] you can put in without loss of properties.”