Alternative fuel

killivolt said:

In a sealed system I.E. Refrigeration if you have the presents of water the mineral oil develops acids.
kv

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Where did you get that idea? Water is not an oxidizer. Pure mineral oil does not react with it at any discernible rate.

John

Nueltralizing acids in refrigeration systems

jpanhalt said:

Where did you get that idea? Water is not an oxidizer. Pure mineral oil does not react with it at any discernible rate.

John

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The oil in refrigeration systems becomes corrupted when you have the presents of water maybe mixing with the refrigerant ? The Technicians have to neutralize it and replace the oil.

**broken link removed**

Therefore organic acids are rarely if ever found in today’s air conditioning systems in any
appreciable concentration.
Both inorganic and organic acids are corrosive. However, inorganic acids have a higher
dissociation constant making them strong and very reactive acids, while organic acids react
much slower. In the case of mineral oils, elevated temperature causes the oil to ultimately break
down and the ultimate products are carbon and hydrogen gas. Only in the presence of an
oxidizer, such as oxygen or air, can organic acids be formed. In the case of synthetic POE oils,
organic acid may be initially present (up to 8 PPM) as a residual from the esterification
manufacturing process used to make the ester oil. It is therefore clear that the real acid problem
in refrigeration/air conditioning systems is an inorganic acid problem not an organic acid.

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kv Thanks John.

Turbine engines such as turbo-props makes use of the water trick as well. It cools the turbine, allowing a higher mass of fuel, hence higher power output.
This trick is only utilised during take-off, otherwise all turbine-like engines has optimum efficiency at 89 to 90% throttle.

And off coarse, the water is not pure either, mixed with methanol. Pilots always talk about water meth injection.

That also influences the whole balance, but the end result is to cool the engine using evaporation.
I also don't think the issue with acid and rust would be same with a turbine engine compared to anything else.
For obvious reasons.

An IC engine produces water as a byproduct of combustion. That is why mufflers rust out.

3v0, you're absolutely right.
Take note though, unleaded does not have a rusting effect on silencers.
I remember back in the day, not that long ago, of leaded petrol here in South Africa, man you were lucky to get two years from a silencer.
Since driving my last three cars, all Fords, on unleaded, I've never replaced a silencer.
And never used a stainless silencer or exhaust system ever.
Now that has been more that 320 000 km, without replacing a silencer or fixing it.
Yet unleaded fuel that has burned also produces water.

arrie said:

Take note though, unleaded does not have a rusting effect on silencers.

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I would completely disagree, silencers rust just as much on unleaded as leaded, I've found no difference at all over all the years the UK has been lead free. I've just had the rear section of my exhaust system replaced for the second time, this on a car that's just over 5 years old - cause, rusted through from the inside, just as they always fail.

arrie said:

And off coarse, the water is not pure either, mixed with methanol. Pilots always talk about water meth injection.

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I didn't know it was mixed with methanol. Makes sense, as the alcohol would act as a wetting agent. The Leidenfrost effect actually slows the vaporization of water when it is put onto a very hot surface (like in a turbine). John

Exhaust systems on cars with catalytic converters run hoter. But if trips are short they never get up to temp.

I have always wondered if the alcahol was there to anything other then prevent the water from freezing. I found this on http://www.turbomirage.com/water.html


I have doubts about water only acting as an intercooler (I am not sure they are saying that). That would not do much to lower combustion temperatures. I think it is the water turing to steam in cylinder that does that.

But they do say that the alcohol acts as a fuel.

3v0 said:

Exhaust systems on cars with catalytic converters run hoter. But if trips are short they never get up to temp.

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I don't do any trips that short, the engine (and exhaust) gets to full temperature everytime I use it.

Nigel,that is weird.
I bought my Ford Ikon in 2002, so six years on, and I have not replaced an exhaust or even worked on it. As it is a budget vehicle, it is not fitted with stainless steel.
Same on the car I had before that, 1996 Ford Escort, no SS, yet I drove it from 1999 to 2003, when I sold it, it had 229000km on the clock.
Don't know if anyone ever noticed, the 1.6 Escort has this funny round box right after the engine, but it was clearly visible underneath the car, I once destroyed the front area of that box when out bundu-bashing with the car on some trip.
Went to the nearest exhaust place, told them to cut it out and weld a normal piece of pipe in its place. That was probably during 2000 or 2001.
That also never perished, nor the welds.
The only explanation I could form for that was the unleaded fuel compared to my first leaded fuel vehicle which went through silencers at about the same rate as tires or batteries.
Do you think UK's comparatively wet climate to our dry climate can be a factor Nigel?
Something else of unleaded compared to leaded, your engine oil retained its oily colour for much longer compared to leaded fuel, where it goes dark almost after the first drive.

3v0, it's the effect of evaporation causing the cooling, your right, we just called it water as that is the state it is stored in.
I'm not sure why the methanol is added as turbine engines does not suffer from knock like IC engines, surely you would not require the extra fuel, jet-A1 already fulfils that requirement without the need to add alcohol.
What pilots do say is that water-meth injections are a great way of having a visible increase in power for take-off. It is switched off after the craft is airborne, so is implemented for only a number of seconds.

Oh, and none of my vehicles use cats, and I probably never will make use of a cat system. And I do quite a share of short trips with my Ikon, not the Mondeo so much.

arrie said:

Do you think UK's comparatively wet climate to our dry climate can be a factor Nigel?

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Possibly?, but as you are already aware, unleaded petrol makes just the same water as leaded does - perhaps you've just been lucky?.

Oh, and none of my vehicles use cats, and I probably never will make use of a cat system.

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Not an option in the UK, as far as I know all recent cars use cats, and they aren't roadworthy without them (yearly MOT tests check emissions, but only on three year old or more vehicles).

I've also been lucky with batteries, seem to get quite a lot of years from them, 5+ years with my Ikon before failing.
I've heard people talking that unleaded fumes are very toxic, but it could be nasty rumours. We've had reports of poor reliability and tremendous expense with cats so I stay clear. It's almost the very expensive and luxury vehicles here that is fitted standard with cats.

arrie said:

I've also been lucky with batteries, seem to get quite a lot of years from them, 5+ years with my Ikon before failing.
I've heard people talking that unleaded fumes are very toxic, but it could be nasty rumours.

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As far as I'm aware it's far better than leaded exhaust.

As for batteries, again you have a warm dry climate

But mine's fine after 5+ years anyway, I can't say I've ever had any great problems with batteries?.

We've had reports of poor reliability and tremendous expense with cats so I stay clear. It's almost the very expensive and luxury vehicles here that is fitted standard with cats.

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It's going to come, there can't be many countries left where they aren't a legal requirement now - as far as I'm aware they are pretty reliable, and a LOT cheaper to replace than they used to be.

If you're hearing about poor reliabilty, it's likely people are still using leaded fuel sometimes - use it once and it destroys the cat.

We don't have leaded fuel any more, haven't had for some years now.
We do have these so called dual fuels, or lead substitute fuels, since we still have quite a number of vehicles from the leaded era on our roads.

So does cats reduce the amount of CO2 emissions?

I would think that we are far from that law over here, maybe by that time some alternative that all manufacturers are claiming to be close will be with us already.

arrie said:

So does cats reduce the amount of CO2 emissions?

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I'm not sure what it reduces, I think it might be CO2 - it's listed on my MOT certificate, but I can't say I paid any attention.

I mean, if you only have water and CO2 after ignition, it must be that.

Except if other toxins exist nobody is really telling us about. Which can bring us back to the rusting saga of earlier.

But I'll have to research that.

More along the line of carbon monoxide to carbon dioxide. Also reduces NOX and unburned fuel.

wikipedia]A three-way catalytic converter has three simultaneous tasks: [LIST=1] [*]Reduction of nitrogen oxides to nitrogen and oxygen: 2NOx → xO2 + N2 [*]Oxidation of carbon monoxide to carbon dioxide: 2CO + O2 → 2CO2 [*]Oxidation of unburnt hydrocarbons (HC) to carbon dioxide and water: 2CxHy + (2x+y/2)O2 → 2xCO2 + yH2O [/LIST][/QUOTE] [QUOTE=arrie said:

We don't have leaded fuel any more, haven't had for some years now.
We do have these so called dual fuels, or lead substitute fuels, since we still have quite a number of vehicles from the leaded era on our roads.

So does cats reduce the amount of CO2 emissions?

I would think that we are far from that law over here, maybe by that time some alternative that all manufacturers are claiming to be close will be with us already.

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Thanks 3v0.
That is interesting.

So my conclusion is that the IC engines are not as efficient in its combustion as they claim.
Otherwise the cat would not be required.

arrie said:

So my conclusion is that the IC engines are not as efficient in its combustion as they claim.

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I don't think anyone has ever claimed any great degree of efficiency for IC engines? - nor does it's specific waste products have any real bearing on it's efficiency, you could probably increase efficiency at the cost of making it's waste products worse.

Nigel Goodwin said:

I don't think anyone has ever claimed any great degree of efficiency for IC engines? - nor does it's specific waste products have any real bearing on it's efficiency, you could probably increase efficiency at the cost of making it's waste products worse.

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No really, most claim combustion efficiency of between 97 and 99%.
I'm not nearly a microbiologist, but them mostly all you should get out is CO2 and H2O, right?