DeNox

[abyssin3]

we are hearing more and more about DeNox systems to reduce NOx emitted by diesel engines.

The best known is to inject urea or ammonia into the exhaust gas.

but why not put it directly in the fuel ???
As a bonus of the Denoxification, it would NH3 + NO3 (ammonia + nitrate = boom) = artificial increase of the cetane number.

Obviously I started the test, finally adding very little ammonia, but I think it rolls pretty well ...
So, I would like to know if anyone has already tried, and if so what are the conclusions to avoid? no effect?

Zac had already told us about the effect of urea (also nitrogen and degrades to ammonia) in a water doping. He said he had observed a drop in the engine brake. I do not see enough difference in the little dose that I put to see such an effect, but in any case, it would go well in this direction.

So the opinions are welcome!

[Christophe]

Ben the fact of burning amoniac or other compound in NHx not only risks to increase the rejection in NOx (or other more toxic product) but especially modifies the molecule which smoked the NOx ... thus effect of the urea "burned" no one in DeNox ...

Finally I see the thing like this ...

For the decline of the engine brake it remains a mystery for me ...

[abyssin3]

Not on apparently the detonation of NH3 and NOx is possible and leads to:
NH4NO3 ----> N2 + 2 H2O + 1/2 O2 (if reaction complete)
(and N2 nontoxic )

In this example, it is ammonium nitrate close to NO3 and NH3. There are other theories on this page:
http://www.sfc.fr/Guiochon/untitled/theoriechim.htm

Anyway, si that (NH4 in fuel) could even slightly lower the conso, it would remind me strangely a fashion manufacturers (ex: urea in escape) which aims to do everything possible to lower emissions even more consume ... and pay more to passage.

[abyssin3]

ZAC
Have you continued since the last time to .... in the water tank to test the effect of urea? If so, do you still have the same effects?
Otherwise, it would not look like you're trying with ammonia 13% ( supermarket) to see if it makes the same effect?

[Christophe]

Not on apparently the detonation of NH3 and NOx is possible and leads to:
NH4NO3 ----> N2 + 2 H2O + 1/2 O2 (if reaction complete)
(and N2 nontoxic )

You know from the equation of combustion of hydrocarbons ... (so theory) there is no CO, neither of imbrulés nor NOx ... You know more ...

After you have to see the respective capacities and conditions of combustion for each product. Actually maybe a little urea additive can improve the combustion (as it could degrade ...)

In this example, it is ammonium nitrate close to NO3 and NH3. There are other theories on this page:
http://www.sfc.fr/Guiochon/untitled/theoriechim.htm

Anyway, si that (NH4 in fuel) could even slightly lower the conso, it would remind me strangely a fashion manufacturers (ex: urea in escape) which aims to do everything possible to lower emissions even more consume ... and pay more to passage.

But nan but nan ... what are you saying

[clopin69]

Hello,
your idea of ​​mixing urea with fuel is incoherent,

Did you put probes in your exhaust to measure?

the principle of transformation of urea into ammonia, is inneficacious, during a combustion with phases of cracking and peroxidation, diesel combustion what .....

the basic idea is to turn urea into ammonia and then this ammonia transforms the nitrogen into nitrogen and water.

a+

[clopin69]

I forgot to say that ammonia and ammonia is not the same thing!

ammonia solution is an aqueous solution, for the household, and ammonia is a gas.

in the case of denox, ammonia gas is used!
a+

[abyssin3]

Thanks for the infos clopin69,

just two things:
1.What Zac was doing was not exactly putting urea in the fuel, but in bubbler water (doping or pantone)

2. What I was talking about was putting ammonia directly into the fuel, so no need for transformation from urea.
Now, the whole thing is to know if this ammoniawhich can turn into ammoniac when it is sprayed into the combustion chamber ...

If so, it would confirm everything:

and then the ammonia transforms the nox into nitrogen and water vapor.

That is: NH4 + NO3 ----> N2 + 2 H2O + 1/2 O2 (if reaction complete)

So by putting in the fuel, (ammonia or ...) it would be good to reduce NOx and the fuel would be more explosive (better cetane number)

PS: Do you know if fuel economy can be important in this case?

[clopin69]

Hello

I do not know if we seek to use a product to obtain two results at the same time, cetane index search, and depollution.

the cetane number serves more to reduce the ignition time without unduly lowering the pressure as well as the noise, than depolluting.

and in diesel we do not try to reduce too much pressure, because it allows this fabulous output that the diesel engine, the engine torque is flat at a certain speed thanks to this high pressure.

personally I prefer a very good engine performance, which will therefore use less go (so - 2 co), but that makes a little noise, and that the clearance occurs after combustion in post treatment.

so to finish and to answer the question I am afraid that the engine performance is less good, so is certainly no gain conso.

here, I did not know if I was clear.

it's up to you to shake me for more info.

a+

[abyssin3]

I'm afraid that the engine performance is less good, so is certainly no gain conso

But in any case it's always good to know for compression, thank you for the info ;-)