In 2010, Volvo Trucks will be the first truck manufacturer to start conducting comprehensive field tests involving Bio-DME, a biofuel that generates very low carbon dioxide emissions. In the long term it has the potential to replace 50 per cent of today’s diesel use for transport operations in Europe.
The field test is being made possible through a joint project DME that is produced from biomass, known as Bio-DME, has both high energy efficiency and low greenhouse gas emissions all the way from the source to the wheel. The raw material used is ‘black liquor’, an energy-rich, highly viscous by-product of the paper pulp industry. By using Bio-DME instead of diesel as a fuel, for example, carbon dioxide emissions can be reduced by up to 95 per cent.
Volvo’s DME FH truck uses a regular D13 engine which, after some modifications to the tank system, injection system and engine management software, functions perfectly together with the biofuel.
An ideal fuel for diesel engines
Compared with a conventional engine, using Bio-DME as a fuel provides the same high efficiency rating along with lower noise levels. The combustion process produces very low emissions of particulates and oxides of nitrogen. Therefore, a simpler system can be used for after-treatment of the exhaust gases. The engine can also provide higher torque at start-up and thus improve driveability. All in all, this makes Bio-DME an ideal fuel for diesel engines.
Modifications to the fuel system
DME is filled in liquid form and stored in pressurised tanks in a leak-proof system which keeps the fuel in liquid form all the way to injection where common rail technology is used to create the optimum high injection pressure. As the energy content of DME is just over half that of diesel oil, it has to be compensated for by fitting larger tanks.
