Diesels and carbon monoxide

[mdregister]

Silly question maybe, but do diesels produce the same deadly gases as gasoline motors?? If so, I was wondering how the truckers keep their trucks ventilated when they are sleeping and the truck runs all night.

[dieselcrawler]

Funny you should ask that... I was talking to someone a few days or a week ago, they claimed that diesel's didn't produce carbon monoxide, or at least not near the toxic levals a gas motor does. I thought they were full of it at the time. So, what's the real deal? Any one know?

Greg

[NH2112]

From what I understand diesels produce higher levels of particulates than gas engines do, but lower levels of HC and NOx. As the engines get miles on them, however, the NOx numbers go up but still not to the point of the average gasser. Sulfates aren't really a problem now with the low-sulfur fuel, either. It's possible to put a scrubber on a diesel and have exhaust cleaner than even an LP engine's - a lot of forklift users are beginning to do this in applications normally filled by LP or electric trucks, due to the limitations inherent in LP and electrics and the advantages of diesels. You just have to let it get uo to operating temp for the scrubber to work.

[moondoggie]

Good Day!

(Here I go again, way over my real level of knowledge. Oh well, never stopped me before

[gavio]

Moondoggie is basically on it, as I understand it. Diesels are much lower in HCs and CO, but higher in NOx and particulates.

In Europe, where they actually have a genuine interest in reducing greenhouse gasses, they have adjusted smog standards to allow for a bit more NOx and soot than we do over here, the tradeoff being that by favoring diesels, they see a much lower production overall in greenhouse gasses.

Far as I'm concerned though, it still doesn't explain how anyone can sleep in such a cloud of exhaust, but to each his/her own.

'Course mine doesn't smell so bad, what with the veggie oil, when it idles in one place for a while, you'd swear someone was barbequeing chicken :D

[mdregister]

Originally posted by gavio:


'Course mine doesn't smell so bad, what with the veggie oil, when it idles in one place for a while, you'd swear someone was barbequeing chicken :D [/QB]LOL when i read that, I had a mental image of your truck with a whole gaggle of dogs/cats lured by the smell, licking the tailpipe.

[CleviteKid]

Since diesels run quite lean (excess air and hence excess oxygen) the thermodynamic tendency is to completely oxidize the carbon in the fuel to carbon dioxide. However, at high temperature (like peak combustion temperatures) entropy effects favor the production of more carbon monoxide and less carbon dioxide. So there is a significant amount of CO (carbon monoxide) leaving the cylinder at the exhaust valve. But as the CO goes thru the exhaust manifold, it reacts with the excess oxygen there and actually burns to make more carbon dioxide. By the time it comes out the tailpipe, essentially all the CO is gone. On very large diesels we see this effect in that the EGT at the cylinder head is often about 100 degrees LESS than the EGT at the turbocharger inlet - due to the combustion of CO in the exhaust manifold.

Dr. Lee :cool:

[moondoggie]

Good Day!

Thanks, doc. I knew SOMEONE (preferably you) would straighten out my gobbledygook. ;)

Blessings!

Brian Johnson, #5044

[Peter J. Bierman]

I heard a comment lately by someone from PSA
( Peugeot, renauld and Citroen ) that their diesel technology is capable of reducing all exhaust gasses to like 60% off todays regulations.
Soot traps reduce particles 80%! :eek:
It's not in production yet but with new Euronorm
regulations coming up, they will be soon.

In the end, regulations are not made to hassle us but to preserve the planet so we and next generations can live on it without wearing gasmasks all day. :rolleyes:

Sorry for the lecture redface.gif

Peter