LONDON: The bulk of Danish vehicles fleet runs on diesel, which is causing air pollution in urban areas, from carbon particles, nitrogen oxides and unburned hydrocarbons.
A new four-year project at Risų DTU (Danish Technical University) is developing an effective method for purifying flue gases, especially exhaust gases, from diesel engines.
Existing solutions to air pollution require the installation of particulate filters and either an SCR catalyst (selective catalytic reduction), a nitrogen oxides (NOx) absorber or recirculation of the exhaust gas. This leads to additional expenditure when modifying diesel vehicles to be less polluting.
Electrochemical flue gas purification has a number of advantages over existing filters making it attractive to target this research at the car industry. Purification of carbon particles, toxic nitrogen oxides (NOX) and unburned hydrocarbons from the exhaust can all happen in the same filter unit.
Another advantage of using electrochemical methods is that it is not necessary to add other substances to the fuel. In addition, the filter can be produced without the use of precious metals. The current SCR technology typically uses the nitrogen-containing urea as a reducing agent to remove NOx from the exhaust.
The purification of exhaust gas will therefore be conducted independently of the engine operation. This technology could lead to significant fuel savings compared with leading alternative technologies. The technology could also be applied in the purification of flue gas from power plants, and possibly in the shipping industry.
The ambitious research project will further develop the technology into a successful prototype for use under realistic conditions in a diesel engine, said a Risų release.
The project is led by Kent Kammer Hansen, senior scientist in the Fuel Cells and Solid State Chemistry Division at Risų National Lab for Sustainable Energy, DTU.
