Step Forward In Diesel Engine Emissions Reduction: System Incorporating a Novel Low Emission Diesel Fuel Combined With a Diesel Oxidation Catalyst

Water-emulsified diesel fuel technology has been proven to reduce nitrogen oxides (NOx) and particulate matter (PM) simultaneously at relatively low cost compared to other pollution-reducing strategies. The value of this technology is that it requires absolutely no engine adjustments or modifications to reduce harmful emissions. Technologies that break the NOx -particulate trade-off are virtually non-existent, therefore understanding how the water contained in an emulsified fuel can reduce both NOx and PM simultaneously is critical.

To understand this phenomenon, emulsified fuels with varying water levels (0 to 20%) were evaluated in a multi-cylinder marine engine using three different injection timings. This testing in an actual engine confirms that as the water level is increased the amount of NOx and PM are reduced without compromising engine performance. Furthermore, injection timing can be changed in conjunction with using an emulsified fuel to further optimize engine performance and decrease emissions. In addition to engine optimization, water emulsified fuel in combination with a DOC was tested and was shown to reduce particulate emissions greater than each technology separately and nearing the level typically offered with a diesel particulate trap.

Recent work on the health and environmental effects of particulates indicates that not only can particulates be deleterious to health but they may be more significant than previously thought in their impact on global warming. This highlights the relevance of this paper in addressing the benefits of emulsion fuels and the timeliness of this technology with regard to the reduction of emissions from diesel vehicles. Data are presented from the laboratory environment, with engine and chassis dynamometer testing, through to the real world which show that emulsion fuels are a viable technology to reduce emissions from a range of vehicles now.