Conclusion of our 2 Part Interview: Emissions Control in Gas Engines through Filter Technology
In this two-part interview, Automotive IQ spoke with Dr. David Greenwell,
Senior Development Chemist at Johnson Matthey Catalysts, UK to discuss
Filtration technology in gasoline engines and to learn about the benefits of filters
vs improving emissions on the engine side. This is the conclusion of our 2 part interview.
"In terms of the vehicle manufacturers doing their own reduction of engine-out
particulates, there is still a lot of learning by the vehicle manufacturers
themselves as to primarily what's the effect of ageing on the engine hardware
Automotive IQ: Do you feel like there's some limit, that Euro 6 is coming toward that limit of filter technology, at least with what's currently available? Or do you feel like there are still ways that you can go and be easily up to the challenge for even stricter legislation?
David Greenwell: Yes, I think we're doing pretty well at the moment. We've got some good robust products. We demonstrated some good products, we've aged those on engines and we've tested them on vehicles and we've shown that we can meet the targets quite comfortably in many cases. We always have an eye on one of the main issues which is back-pressure. We need to minimize back-pressure to the filter but we're now getting a much better understanding of how we can integrate the three-way performance and the filtration characteristics on a brick and have the minimum impact on back-pressure possible. So now we have more vehicles available to us to test on and a better idea of the engine-out emissions the car manufacturers are going to be dealing with. Again, we can tune our products to match those requirements, so we're not making over specified systems in terms of filtration.
Automotive IQ: My understanding is that one of the current ways to measure if a system is functioning correctly is to measure back-pressure, is that correct?
D.G.: I believe, yes. There's a presence of catalyst detection for OBD that may be possible. So you can use lambda sensors and back-pressure sensors to actually just detect that there is a filter there or not. But certainly in diesel cars at the moment, yes, back-pressure is used a lot for monitoring the performance of the system, particularly for regeneration. This is more of a challenge for gasoline applications however as the soot loadings are lower...
This is part 2 of a 2 part interview with Dr. Greenwell.
In case you missed Part 1: Emissions Control in Gas Engines through Filter Technology