Deep-frozen car tyre disposal

Press, Volume CXIV, Issue 33425, 5 January 1974, Page 14

Deep-frozen car tyre disposal

An Australian engineer has developed a method of disposing of old car tyres by freezing them to almost 200 degrees Centigrade below zero.

Dr J. Barnes, a lecturer; tn chemical engineering with the New South Wales Institute of Technology, Sydney, said that when frozen the tvre became brittle like glass, and could be smashed into particles in a special crushing device. The particles were then further reduced into reusable rubber by-products. Dr Barnes is testing uses, of the by-products, applications of which he said included rubber surfacing for, school playgrounds, running' tracks and basketball fields. Also the by-product mixed, with bitumen and sand an application as a non-skid; road surfacing in dangerous; areas. It could be used tooj for carpet backing and industrial floors. The present methods of disposing of old tyres were difficult and expensive, as they were either buried or burnt in specially constructed furnaces. Most councils refuse to take them at local dumps because they create an air pollution problem if they catch fire." said Dr Barnes. “Even if thev are covered with soil thev rend to work their way to the surface. They don’t

I decay to any great extent in the soil." The by-products would payi for the cost of freezing and' crushing the tyres, said Dr Barnes. He said that two; large Sydney companies were co-operating with him in his studies and final large scale experiments would be done in the next few months to I determine the economic feasibility of the process. The engineering problems had virtually been solved.