Experience of Fitting London Black Cabs with Fuel Borne Catalyst Assisted Diesel Particulate Filters - Part 1 Regulated Emissions and Regeneration Performance

Forthcoming emissions legislation is driving the passenger car manufacturers towards the fitting of Diesel Particulate Filters (DPFs) as original equipment. However such initiatives are not retrospective and due to the replacement rate of the vehicle fleet, there is a time lag before the full benefit of the new measures are fully realised. To overcome this drawback, in areas with a particular problem such as heavily congested city centres, retrospective legislation has been introduced, for example in Hong Kong and Tokyo. Legislation mandating the retrofitting of DPFs obviously has an immediate effect on particulate emissions. Other authorities are thus investigating the efficacy of such measures.

To add to the data base for such assessments Octel is running a demonstration programme using London Black Cabs. Four cars have been fitted with a DPF, an on-board dosing system to meter a fuel borne catalyst (FBC) into the fuel and a data logger to monitor the DPF performance. Emissions measurements were taken before and after fitting the DPF. The cars were then run on the road conducting normal taxi duties. After approximately 20000 km the cars were brought back for a further set of emissions measurements to be performed with the DPF fitted and again with the DPF removed.

This paper presents details of the installation of the DPF systems, an analysis of the in service operational performance of the system. Also presented is an analysis of the results of the regulated emissions testing with and without the DPF. A follow-on paper describes the results of some non-regulated emissions.