Engineers at Queensland University of Technology (QUT) have tested the oil extracted from old tires in a process developed by Australian company Green Distillation Technologies (GDT).
QUT’s professor Richard Brown and phd student Farhad Hossain tested the oil’s emissions and output at QUT’s Biofuel Engine Research Facility.
Brown said that when the oil was blended with diesel it was found to produce a fuel with reduced emissions and no loss of engine performance.
The QUT engineering team, including process engineer Dr Tom Rainey and air-quality expert professor Zoran Ristovski, performed a number of rigorous tests on the oil.
“We tested the oil which GDT produces from both recycled natural and synthetic rubber tires in 10% and 20% diesel blends,” Farhad explained.
“We tested the tire 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.
“Our experiments were performed with a constant speed and four different engine loads of 25, 50, 75 and 100% of full load. We found a 30% reduction in nitrogen oxide which contributes to photochemical smog, and lower particle mass which means fewer problems for emission treatment systems.”
GDT COO Trevor Bayley said the oil could also be used as a heating fuel or further refined into automotive or aviation jet fuel.
“The process recycles end-of-life tires into oil, carbon and steel, leaving nothing wasted and even uses some of the recovered oil as the heat source,” Bayley said. “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.
“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 tire yields 40-liters of oil, 1.5kg of steel and 4kg of carbon, and a 70kg truck tire provides 28-liters of oil, 11kg of steel and 28kg of carbon.
“GDT plans to have the first fully operational commercial plant delivering eight million liters of oil a year from mid-2017, followed by a world-first mining tire processing plant in either Queensland or Western Australia.”