Growing concern over the health effects of airborne particles and a desire to reduce the associated cost has resulted in legislation, regulations and other measures, in the industrialised world to severely restrict particulate emissions from diesel-fuelled automotive transport. Developing countries are also introducing initiatives to try and reduce emissions, an example is the legislation in India to replace diesel engines with gas fuelled engines in some major conurbations. Such measures are expensive, both in terms of replacing the engines of the vehicles and of implementing the required infrastructure. There is still also debate over whether such measures reduce the number of ultra-fine particulates.
A well-proven alternative is to fit diesel engines with Diesel Particulate Filters (DPFs), either as original equipment or as a retrofit system. Regenerating DPFs has in the past been an obstacle to their widespread application. The use of a Fuel Borne Catalyst (FBC) is an accepted method of promoting regeneration and hence widening the applicability of DPFs.
This paper considers some alternative solutions to reducing diesel particulate emissions, including the cost to implement these different solutions, the real benefits and possible negative effects. It concludes that the most cost-effective solution is to fit DPFs to new and existing vehicles and to use a FBC to ensure efficient regeneration of the DPF.
This paper also present the results of work that has been undertaken to prove the efficacy and durability of the DPF/FBC solution. A number of different vehicle types have been tested covering a range of engine technologies and vehicle size classifications. Details are also presented of techniques that can be used to reduce the cost of implementing DPF/FBC systems in retrofit applications.