Using Hydrogen Gas to De-Carbon An Engine?

[DoubleWasp]

There's a process that's popular overseas, now coming into the US where they use a machine that feeds hydrogen gas into an engine's intake for about 30 minutes to remove the carbon from an engine. Claims to remove carbon from intake, combustion chambers, turbos, exhaust, everything.

Am I the only one a little concerned that hydrogen embrittlement can rear it's ugly head under this process and cause engine damage? It's been a major hurdle to the hydrogen ICE movement for a while.

There's a local company that's recently been pushing this on the marine industry.

 

[Supercalifragili]

You can just use water..

YouTube user BMAG VACS had the best video on it, how to mist it into an intake on a fully warmed engine, one driven an hour or so, preferably on the highway, hard.

 

[CT8]

I am not sure hydrogen embrittlement would be an issue used as a "fuel" even though the purpose is not used as a fuel.. I only know in that some plating and welding process can cause the problem. I am sure one of the engineers on board can tell us about if it will be a problem.

 

[CT8]

double post.

 

[WellOiled]

This sounds good. I've seen the videos of the water injection as well as the Seafoam and it seems only a minuscule amount of carbon is actually removed. Since you need an oil change about 200 miles after, I have avoided these 2 methods.

Since the carbon built up 1 molecule at a time, I am trying to remove it 1 molecule at a time. The following seems to work but slowly.

I use an upper cylinder lube. 50% MMO and 50% TCW3. 1oz per 5 gallons. About once a week or next morning if I hear any pinging. I run 3-5 miles above 3000 RPMs after the engine is good and hot. The pinging will be gone after each high RPM set.

I tried Techron and got no where. This truck has had a steady diet of M1 and Top Tier gas. So I am puzzled as to how the carbon built up in the first place. The nature of a large displacement V6 that does not get run hard enough???

 

[Eddie]

The best and maybe only thing that really works well is a paint scraper and a wire brush, followed by a solvent hi temp wash.

 

[WellOiled]

Exactly what I was hoping to avoid.

I will stick with what I am doing until something better / cheaper comes along.

 

[simple_gifts]

Walnut shells; it is like a decades old solution.



Probably only gets some of the components, not the whole thing.

Not sure if you are asking about decarboning an engine or are just curious about the H2 method.

 

[Ducked]

Water works for me.

I like that its free, and has a known physico-chemical explanation.

I think its the oxygen in the water that is effective. Hydrogen, not so much, but water gives you that as well.

H2O + C -> C0 + H2

 

[ecotourist]

Originally Posted By: Ducked
H2O + C -> C0 + H2

Do you think so? That would have the makings of an energy generating machine. You could spray water on C, then burn the CO and H2. But I don't think that's what happens

I think H2O + C = dirty water. But that's just what you want. The C is no longer where it was.

 

[Ducked]

Originally Posted By: ecotourist
Originally Posted By: Ducked
H2O + C -> C0 + H2

Do you think so? That would have the makings of an energy generating machine. You could spray water on C, then burn the CO and H2. But I don't think that's what happens

I think H2O + C = dirty water. But that's just what you want. The C is no longer where it was.


Don't have to think. I did "O" level Chemistry

Look up "water gas". Used to make town gas a couple of hundred years ago.

This is happening in a running engine. Its hot, and the carbon is incandescent. The water breaks down to free radicles and reacts with the carbon.

 

[kschachn]

Originally Posted By: Ducked
Don't have to think. I did "O" level Chemistry

Look up "water gas". Used to make town gas a couple of hundred years ago.

This is happening in a running engine. Its hot, and the carbon is incandescent. The water breaks down to free radicles and reacts with the carbon.


At net energy input of course. There is no free lunch in the thermal decomposition of water.

I'm not even sure carbon decomposes water at elevated temperatures. No doubt that if it does you're going to get a lot of CO too.

 

[ecotourist]

Yes it seems there is such a reaction. You learn something every day.

But I doubt that this is what happens in an engine. If the carbon were actually incandescent as is apparently required, in the presence of oxygen it would simply burn off - ie it wouldn't be there in the first place. There'd be no need for water.

I suppose you could set up a situation with a coked engine, kept under high load, now very hot, with a slow water trickle into the intake where you'd get some of this reaction, but that's not how people typically use water as a combustion chamber (or valve) cleaner - more likely an idling, unloaded and as a result not very hot engine.

You'd probably have to set up an experiment using tracers to see for sure what happens. But my bets are still on the water (and steam) acting mostly as a solvent in a typical water based clean up.

 

[Ducked]

Take one lump of coke. Dilute to taste with boiling water.

Your coke soup won't taste much of coke. It'll be more like a lump of coke in some water.

Can't rule out solvent effects altogether though. They won't dissolve carbon but I suppose they might have some effect detaching it from surfaces.

 

[Ducked]

Originally Posted By: ecotourist
that's not how people typically use water as a combustion chamber (or valve) cleaner - more likely an idling, unloaded and as a result not very hot engine.


Then they are doing it wrong.

 

[Ducked]

Originally Posted By: ecotourist

But I doubt that this is what happens in an engine. If the carbon were actually incandescent as is apparently required, in the presence of oxygen it would simply burn off - ie it wouldn't be there in the first place. There'd be no need for water.



By that logic a coked-up engine is impossible, so the discussion is er..moot?

The water provides excess oxygen. I suppose oxygen must be in limited supply in an operating engine, otherwise, it wouldn't coke-up in the first place.

 

[Shannow]

Originally Posted By: kschachn
At net energy input of course. There is no free lunch in the thermal decomposition of water.

I'm not even sure carbon decomposes water at elevated temperatures. No doubt that if it does you're going to get a lot of CO too.


Oh yes, certainly.

This town had "town gas" for decades, not sure if you are familiar with the old british/Australian method of comitting suicide by placing your head in the oven...the CO takes you out very very quickly.

The town gas is destructive pyrolisis of coal, which creates H2, CO (syngas), and CO2 and H20.

The more efficient process that was later adopted took the combustion heat to do the "water gas" trick.

Flue gasses boiled water to steam, and the coal was pyrolised in two parallel chambers. Air would go into one, and when the coal was incandescent, air would be shut off and steam introduced. The parallel chamber then got air, and they swapped as they cooled from the energy dissociating steam.

A later additional method was "oil gas" where waste oil from various refining processes was introduced as well.

When I was managing the coal plant at the power stations, if the coal spontaneously combusted, I had to stop people many times spraying water mist onto it in and enclosed area (e.g. underground bunker with overhead lighting...scared me witless every time I found them doing it).

 

[ecotourist]

Originally Posted By: Ducked
Originally Posted By: ecotourist

But I doubt that this is what happens in an engine. If the carbon were actually incandescent as is apparently required, in the presence of oxygen it would simply burn off - ie it wouldn't be there in the first place. There'd be no need for water.



By that logic a coked-up engine is impossible, so the discussion is er..moot?

The water provides excess oxygen. I suppose oxygen must be in limited supply in an operating engine, otherwise, it wouldn't coke-up in the first place.

Let's consider the case of the valves in a DI engine - one of the most relevant coking concerns today. You can (and sometimes do) get coke on the cool side of the intake valves - valves cooled by incoming combustion air - and not washed by solvents in the fuel - because there is no fuel in the incoming air of most DI engines (some Toyota engines being one exception). There are engine oil residues (a source of carbon) courtesy of the PCV system. The intake valves of some DI engines presumably don't get hot enough to burn off the resulting carbon. There is plenty of oxygen so that's not the issue. And if you injected water upstream of these intake valves I highly doubt it would change into CO and H2. Any cleaning action would be by water blasting +/- solvent action. I'm prepared to be shown I'm wrong but I'd want to see experimental evidence.

If that carbon on intake valves could get hot enough to drive C and H2O to CO + H2 it wouldn't be there because (as you say) it would have burned off long ago.

And that's why there is no unusual problem with coking of the exhaust valves of DI engines. As with most engines, exhaust valves do get hot enough to burn off any carbon.

Designing a DI engine that doesn't coke its intake valves is pretty good engineering. And the designer can be helped out by an owner who gets the engine hot frequently and runs it hard from time to time.

 

[Ducked]

I'm reminded of the first Windscale fire.

Air-cooled graphite moderated nuclear pile with a striking resemblance to a pot-bellied stove, which turned out to be not coincidental.

Fire brigade skooshed water into it (they were sort of.. er..out of options), and it DIDNT EXPLODE.

So it must have been safe.

 

[Ducked]

Originally Posted By: ecotourist
Originally Posted By: Ducked
Originally Posted By: ecotourist

But I doubt that this is what happens in an engine. If the carbon were actually incandescent as is apparently required, in the presence of oxygen it would simply burn off - ie it wouldn't be there in the first place. There'd be no need for water.



By that logic a coked-up engine is impossible, so the discussion is er..moot?

The water provides excess oxygen. I suppose oxygen must be in limited supply in an operating engine, otherwise, it wouldn't coke-up in the first place.

Let's consider the case of the valves in a DI engine - one of the most relevant coking concerns today. You can (and sometimes do) get coke on the cool side of the intake valves - valves cooled by incoming combustion air - and not washed by solvents in the fuel - because there is no fuel in the incoming air of most DI engines (some Toyota engines being one exception). There are engine oil residues (a source of carbon) courtesy of the PCV system. The intake valves of some DI engines presumably don't get hot enough to burn off the resulting carbon. There is plenty of oxygen so that's not the issue. And if you injected water upstream of these intake valves I highly doubt it would change into CO and H2. Any cleaning action would be by water blasting +/- solvent action. I'm prepared to be shown I'm wrong but I'd want to see experimental evidence.

If that carbon on intake valves could get hot enough to drive C and H2O to CO + H2 it wouldn't be there because (as you say) it would have burned off long ago.

And that's why there is no unusual problem with coking of the exhaust valves of DI engines. As with most engines, exhaust valves do get hot enough to burn off any carbon.

Designing a DI engine that doesn't coke its intake valves is pretty good engineering. And the designer can be helped out by an owner who gets the engine hot frequently and runs it hard from time to time.


Seems reasonable, but also slightly irrelevant to the situation IN an operating engine, as per your quote of me above.

The back of the valves is outside the combustion chamber and so in excess oxygen, but apparently they don't always get hot enough to burn off gunk, since they're cooled by the incoming air.

I dunno if water cleaning works for DI intake valves, never having had one, or tried it, or heard of anyone that has, though someone must have. So its not most relevant to me today.

If it works it would suggest that water also works as a solvent in this situation, since I'd doubt (though I dont know) that it gets hot enough for the water gas reaction.

Given that blowby gases include water but intake valves exposed to them still coke up, perhaps it doesn't work very well?