How’s about we burn hydrogen in the firebox–a hydrogen-fueled steam engine?
Practical in the real world? Probably not. Efficient? Nope, not really.
But it still seems like it should be tried, just once.
Ed
For a slightly different carbon-neutral idea, methane can be produced on an industrial scale from manure or landfills.
Outside of propane-fired live steam models, has anyone ever built a gas-fired steam locomotive?
Problem with hydrogen is that there is very little radiant heating - probably want to take a look at steam generators from gas cooled reactors.
How to burn hydrogen the fun way [;)]: (turn up the volume LOUD!) https://www.youtube.com/watch?v=uuYoYl5kyVE
The steam locomotive offers the advantage of burning solid fuel that is not usable any other way. Coal and wood, mainly, but there is that group in Minnesota restoring a Santa Fe Hudson locomotive (are they still active) who are emphasizing a carbon-neutral “bio coal.”
Coal, wood, or “bio coal” can be converted to liquid fuel for use in more energy efficient internal combustion engines, but depending on how you do it, such synthetic liquid fuels take a lot of energy to make, and L. D. Porta thought that a steam engine of improved efficiency could be in the running as an alternative to making liquid fuels out of solid-fuel biomass.
Gaseous fuels are the least advantagous for use in transportation, especially hydrogen gas that takes a lot of energy to store in compressed form and a huge amount of energy to story in cryogenic liquid form.
This emphasis on “luminous flame from carbon particles” being essential for heat transfer is perhaps misplaced as the reason to not consider hydrogen firing a locomotive boiler. I don’t know anything about burning hydrogen that if you put a pot of water over it that you want get it to boil. The real reason is that hydrogen is expensive to make from natural gas, currently even more expensive to make by electrolysis of renewable sources of electricity, perhaps cheaply made in high-temperature gas-cooled nuclear reactors which we don’t have at commercial scale, and perhaps used in other applications – such as energy-efficient fuel-cells – before considering using it as a boiler fuel.
I’m not sure how methane can be carbon neutral, since CO2 is a byproduct of combustion.
Ed
I am certainly not saying that a hydrogen powered steam locomotive would be especially useful. Or efficient.
It’s that the idea just sort of charms me.
I do see that there are no “glowing particles” with hydrogen combustion. Still, there’s an enormous amount of energy; and I suspect there would be a way to transfer it into the water jacket of the boiler.
Ed
The idea is that the carbon being released originally came out of the atmosphere, in the example of cattle manure the pathway is air-grass-cow-manure-methane-air. The atmosphere does not see a net gain of CO2, so this example is carbon neutral. The same goes for burning wood or other biomass.
Of course, the livestock and landfill examples can get complicated when you try tracing exactly how much of that carbon originally came from fossil fuel hydrocarbons that were used to make things like fertilizer and other synthetic materials.
Sorry but your example is flawed. Burning methane is not carbon neutral any more than coal or oil are, just in a lesser amount of CO2 released. Natural gas is primarily methane.
I’m not talking about natural gas from underground, which is of course being a fossil fuel is not carbon neutral.
I’m talking about methane that is produced by fermenting or digesting biomass. Maybe you don’t have any of these in the U.S, but several large cattle feedlots out here use their manure to produce gas, and this can be done with some other types of biomass as well.
As I outlined in my above post, burning biomass does not add any net additional carbon to the atmosphere, all that carbon originally came from the atmosphere when the plants grew.
Carbon neutral makes a distinction between fossil fuels and biologic fuels. Methane burning from an oil&gas well takes carbon that was fixed underground and puts into the atmosphere. Manure carbon is not fixed, and will brake down to CO2, so burning that carbon does not add to atmospheric carbon load.
Edit: I see the previous poster beat me to it while I was still typing.
Going with that idea, IF you create methane from CO2 from the atmosphere and from H2O, that is likely true. It can certainly be done. And IF you say that the plants and animals producing methane are simply replacements for the human-built extraction system, THEN you might have a point.
Or maybe not. But it does deserve consideration.
I will add that methane is the least CO2-generating substance that can be used for combustion for energy production. Except for hydrogen. Might be something else, but I can’t think of it.
HOWEVER.
I wanna keep this topic with using hydrogen. If you seriously want to start talking about using methane instead, start another topic. I will likely be there.
Ed
Gaseous fuels might be the least advantageous, but in this topic, it is assumed they will be used.
The same applies to the expense.
I am FIRST interested in how to pull it off. The other stuff is currently secondary.
I decided to post this topic because I read an art
The concern is somewhat similar to anthracite firing in that the energy release heats some of the boiler components to failure before substantial nucleate boiling occurs to produce the necessary mass flow of steam within packaging constraints. It does not help that radiant energy from the transparent hydrogen flame is concentrated into a limited number of power spectra.
There is, of course, no reason why ‘renewable’ carbon could not be injected into an oxyhydrogen flame to make it luminous. That precise functionality was used to make oxyhydrogen a practical lighting source (limelight NOT being something that scaled to home lighting needs!) via the ‘ambocarbon’ burner. Other materials that incandesce appropriately could be used, but they would either have to be ‘recycled’ in the exhaust or pose no pollution hazards if emitted – we could take up that discussion but carbon itself is well suited if derived from short-term atmospheric capture or sequestration.
It does have to be said that some research into submerged-flame boilers was done including hydrogen as a fuel, and if you have a cost-effective source of hydrogen and separated oxygen (e.g. at 60-80psi molecular sieve) this provides interestingly complete heat transfer. Not all boilers involve the old parody of the Alco marketing ‘fire-soot-a pipe-scale-water’ in heat transfer.
It should be added, though, that it is still more efficient to use something like the Oxford Catalysts cycle with dilution adjusted to the necessary degree of superheat (we used 735 to about 850; you can go higher with either oilless construction or an asynchronous compound) using renewable-based ethanol. (You could convert biomethane to methanol to r
IF I place a burner in a steam locomotive firebox, and feed it hydrogen, will it “boil water”?
Ed
Liquid Hydrogen is used as rocket fuel, so it seems there would be some way it could boil some water. Of course you might need NASA’s budget.
I’ve seen a figure stating that liquefying a given amount of hydrogen takes 30% of the total energy that will be available from that given amount of hydrogen. Main issue is the amount of work needed to pump heat from 20K to 300K. An ideal Carnot refrigeration cycle would need ~15 Joules of work for every Joule of heat extracted.
LNG has similar issues, but it only needs to be cooled to 130K or so.
Steam loconotive boilers, especially ones with large combustion chambers, are designed for using the radiant heat from hot carbon particles. The B&W book on Steam shows that a considerably larger water wall boiler is needed with natural gas than from coal. A hydrogen flame would dictate a larger heat transfersurface area and I suspect that the general design of steam generators used in helium cooled reactors would work well for a hydrogen flame, taking onto account that hot water vapor tends to be more corrosive than hot helium.
All said and done, I would also think that biofuels would make more sense.
Study the history of oil firing. By the time you build a hydrogen burner with the heat release needed to make the necessary mass flow of steam without overheating some parts of the structure you’ll be spending much more money on top of the upside-down economics of hydrogen as a carrier fuel.
There’s a reason hydrogen didn’t succeed as an aircraft fuel, too. I suggest you study why that was so. Much of the lessons learned are still applicable even with modern materials and design/fabrication techniques.
In case you were wondering why that Cisleresque NaBH4 has such sirenlike appeal over the years, it’s because it gets around the energy and other issues of cryo on the one hand and the weight and release issues of metal hydriding on the other.
Is that energy not returned?
Sounds like no radiant heat from hot carbon particles. So then, what happens to the energy when the hydrogen is burned. If it is not radiant, then it will be conductive, through the atmosphere, to the container of water. Will probably need a lot more surface–fins, and such.
Undoubtedly.
Ed
That’s got me envisioning a “fireless” locomotive, where a RECENTLY mixed hydrogen/oxygen are injected into the water and ignited. Thus generating heat and more water.
Ed