Specific smell of modern diesels

[yannko]

Hello everybody ,

I've been wondering for some time about the rather particular smell of modern diesels (common rail, turbo-compressed).

I noticed that on the exhaust (often smoke-free), we smell like a kind of perfumed odor, in any case very different from the older generation atmo diesels. It reminds me a little of the smell of ozone when photocopying in a small room, or a little that of bleach. In fact, it doesn't smell bad, and it intrigues me because the difference is quite huge. Could it be the smell of nitrogen oxides If yes, it must be well saturated anyway !

The diesels I have known (PSA 1.5 and 1.9d without turbo, and even the old turbo-diesel like 2.1 TD) really have the classic smell of burnt diesel, quite abominable, and it smokes, they are easily recognizable .

Or would it be the residual odor of the catalyzing

[Macro]

Also noticed. Nitrogen oxides would be surprising given the combustion temperatures of these diesels ... All I know is that when I doped my old generation diesel with gas from an electrolysis of l he smelled exactly that smell ...

[yannko]

Thank you for your Macro response ! Ah, that's interesting, that this smell appears with water doping!

It's interesting, I think, because an odor can often betray a chemical process, or something that we wouldn't normally think of.

Maybe it could really be ozone Because when you talk about electrolysis of water, there must be an excess of O2 formed, maybe afterwards, at the exhaust it is possible to find O3 in greater quantity, where the smell?

[chatelot16]

it's been a while that I find in the countryside odor odor, like chlorine pool, but not exactly ...

in summer I put this on the back of a pool with too much chlorine, but in winters?

I finally understood that it was after crossing certain cars: it reminds me of diesel particulate filter, which injects a special chemical: urea or whatever

the manufacturers do not let the customer fill the additive tank themselves: they fill it at the compulsory revision: the customer does not even know that his car consumes a chemical ...

[Obamot]

... I barely left a discussion with the chimney sweep of the corner, to whom I asked questions of safety on the special burners allowing to heat with the recovered oil. or pantone type combustions. He started off with a huge laugh, telling me that fuel oil combustion had made such progress that today a possible gain with water enrichment with other means , would be barely measurable and that all things considered it would no longer be worth the trouble. He said that modern combustion has nothing to do with the old. The yields achieved are breathtaking. They can now safely use plastic chimneys, since the gases leaving a boiler are at temperatures not exceeding 50 ° C. I imagine that for a diesel vhc equipped with catalyst it must be the same, combustion has evolved much more than we imagine ...

[yannko]

I finally understood that it was after crossing certain cars: it reminds me of diesel particulate filter, which injects a special chemical: urea or whatever

the manufacturers do not let the customer fill the additive tank themselves: they fill it at the compulsory revision: the customer does not even know that his car consumes a chemical ...

Apparently, urea is used as deNOx on newer vehicles (adBlue), so I don't think this odor comes mainly from there, since many older diesels (like 2000s to now) also have that characteristic smell of bleach.

... I barely left a discussion with the chimney sweep of the corner, to whom I asked questions of safety on the special burners allowing to heat with the recovered oil. or pantone type combustions. He started off with a huge laugh, telling me that fuel oil combustion had made such progress that today a possible gain with water enrichment with other means , would be barely measurable and that all things considered it would no longer be worth the trouble. He said that modern combustion has nothing to do with the old. The yields achieved are breathtaking. They can now safely use plastic chimneys, since the gases leaving a boiler are at temperatures not exceeding 50 ° C. I imagine that for a diesel vhc equipped with catalyst it must be the same, combustion has evolved much more than we imagine ...

Thank you for this testimony, it's interesting! Maloche has a huge subject on the recycling of exhaust gases in a fuel boiler, the results are convincing. I think that an oil boiler always produces oxides of sulfur, nitrogen and unburnt without injecting water or EGR.
I agree for diesel, the pollution control technology has largely improved, but the performance remains quite similar (although also in progress).
Despite everything, we are not given much information on what the exhaust gases contain, apart from CO2 and particles ...

[Christophe]

Ah, I'm happy with this subject creation: I've been asking myself this question for a few years.

There is clearly a chlorine smell coming out of modern diesel engines, it already dates from the time when I was still in Strasbourg, that is to say in the early 2000s ...

At first I thought it was the additive used eolys cerine which could contain chlorine but the fact is that it is no longer used currently so I do not know ...

https://www.econologie.com/filtre-a-part ... s-406.html

[yannko]

Ah thank you Christophe, I had not seen this article about the particle filters!

I also indeed think that this is not the main reason for this smell (given the quantity, up to 0.05% of the volume of diesel), since we also find the famous smell on diesels without FAP.

From now on, really all diesels smell this odor more or less, whether it be TDI, HDi, DCi, CDI, ... in short, everything that is modern.
I think it will take a little bit of Captain 'Maloche to the rescue to measure what comes out of our hearses !

[chatelot16]

if all the diesel smell this odor it is perhaps that there is a new component in the diesel for a few years, without the knowledge of our free will?

more seriously this odor has perhaps always been hidden by the big odor due to sulfur: now that there is no more sulfur we feel it better

[yannko]

I said to myself the same as you chatelot, but by using this same fuel in an engine with injection pump (not catalyzed, not turbo-compressed), the smell is that very "traditional" of the burnt gas oil . So for me, it comes from the engine or the technology used, rather than the fuel.

Regarding sulfur, it is clearly progressing, we went from 10 ppm to 000 ppm since 50, in Europe we are generally at 2005 ppm (10 standard).
The quality of diesel is clearly improving.

Well, I read the differences in toxicity between diesel and petrol , well it is better to fill up with diesel than unleaded, we breathe less cheeriness and we still risk less fire.