Exhaust gas fuel reforming to achieve fuel saving

[摘要] As much as 70 to 75% of the energy in the fuel used by a car is turned into waste heat, with more than a third of this released through the exhaust pipe. Catalysis offers a way of recovering exhaust heat. By adding some of the fuel to a portion of the exhaust as it passes through a catalytic reactor, it is possible to produce a gas mixture with a higher heating value than the fuel. This strategy depends, however, on the catalytic reaction consuming heat, while generating readily-combustible products that can be fed back to the engine. An investigation into catalytic exhaust gas fuel reforming and its potential to improve engine emissions and efficiency when close-coupled to a spark ignition engine. Initial ethanol reforming reactions with simulated exhaust gas suggests that the desired reforming path, i.e. dry reforming, steam reforming and partial oxidation reforming reactions can raise the heating value of the input fuel (ethanol) by up to 120% providing exhaust gas temperatures are made available, with the highest being steam reforming > dry reforming > oxidative reforming. The undesired water gas shift reaction is inactive with this reforming catalyst, regardless of the reaction temperature and reactant ratios (e.g. O:C and H\(_2\)O:C). The characteristic of each reforming path is tentatively explained with deviations from the stoichiometry. Actual exhaust gas fuel reforming studies of gasoline is carried out at a range of exhaust gas temperatures. It was found that at exhaust gas temperature 600\(^0\) to 950\(^0\)C, the overall process efficiency ranges from 107 to 119%. By replacing 23.9% of gasoline fuel with simulated reformate, improvements in engine specific fuel consumption (SFC) and emissions (e.g. NOx, HC, CO2, CO) was achieved.

[发布机构] University:University of Birmingham;Department:School of Engineering

[关键词] T Technology;T Technology (General)