Researchers at the QUT’s Biofuel Engine Research Facility have created a way to turn old tires into biofuels. Facility Professor Richard Brown and PhD student Farhad Hossain tested the oil’s emissions and output and found the biofuel reduced emissions with no loss of engine performance.
“Globally, 1.5 billion tonnes of tyres are discarded each year. Australia, alone, will generate 55 million disused tyres a year by 2020,” said Professor Brown. “Getting rid of old tyres in an environment-friendly way is a universal nightmare. Stockpiles of used tyres around the world are a health hazard, as demonstrated by the recent Broadmeadows fire in Victoria, which was difficult to put out and generated huge amounts of toxic smoke.”
Tests on the oil produced from old tires was performed by Hossain along the QUT engineering team that included process engineer Dr. Tom Rainey, and air-quality expert Professor Zoran Ristovski.
“We tested the oil which GDT produces from both recycled natural and synthetic rubber tyres in 10 percent and 20 percent diesel blends,” Hossain explained. “We tested the tyre oil blends in a turbocharged, common rail, direct injection, six-cylinder engine in the Biofuel Engine Research Facility at QUT. The engine is typical of engine types used in the transport industry.”
He continued, “Our experiments were performed with a constant speed and four different engine loads of 25, 50, 75 and 100 percent of full load. We found a 30 percent reduction in nitrogen oxide which contributes to photochemical smog, and lower particle mass which means fewer problems for emission treatment systems.”
According to Trevor Bayley, GDT COO, the oil can also be used as a heating fuel or further refined into diesel or aviation jet fuel.
“The process recycles end-of-life tyres into oil, carbon and steel, leaving nothing wasted and even uses some of the recovered oil as the heat source,” said Bayley. “Carbon is the most common recovered ingredient and the steel rim and framework is the third most common ingredient, while the oil is the most valuable. We are delighted at the findings of the QUT research as it will help us promote the sustainable use for end-of-life tyres.”
Bayley continued, “The potential of this source of biofuel feedstock is immense, and it is more sustainable than other bio-oils from plants such as corn, or algae. A recycled 10kg car tyre yields 4 litres of oil, 1.5kg of steel and 4 kg of oil, and a 70kg truck tyre provides 28 litres of oil, 11kg of steel and 28kg of carbon. GDT plans to have the first fully operational commercial plant delivering eight million litres of oil a year from mid-2017, followed by a world-first mining tyre processing plant in either Qld or WA,” he added.