Evaluation of Catalysed Hydrocarbon Traps in the EGI System: Potential for Hydrocarbon Emissions Reduction

Catalysed hydrocarbon traps (CHT) have been tested in conjunction with the Exhaust Gas Ignition (EGI) system to assess their combined impact on cold start total hydrocarbon (THC) emissions reduction.

Vehicle emissions profiles have been obtained for each of the regulated emissions along with speciated HC exhaust gases for each of the different CHT-EGI combinations studied in the program.

Results show that the combination of EGI and an upstream CHT lead to a reduction in THC emissions of 30% during the 1^st 195 sec of the New European Drive Cycle. In addition, the EGI system alone, and in conjunction with a CHT comfortably achieves the proposed European Stage IV legislation for each of the regulated emissions at 50k miles. The significance of the results are discussed with reference to both standard drive cycles and off-cycle emissions.