Interesting how they bring hydrogen bombs into the discussion, considering there is no comparison whatsoever.
It appears that both the cars and the train are using the same technology - the hydrogen is used to make electricity which is then used to power the vehicle. The concept has been around for a while, and has even been used for submarines.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
Larry, I expect that the author(s) felt it necessary to inform those who know little, if anything, about the different isotopes of hydrogen that the hydrogen in the cells is not anywhere near as dangerous as the hydrogen in the bomb.
Johnny
Not as dangerous. But anybody remember the Graff Zepelin?
daveklepper Not as dangerous. But anybody remember the Graff Zepelin?
Dave, I wish I had been able to see the Zeppelins and ride on one. The pictures always looked like a neat way to travel.
I read a theory that the Hindenburg's problem was not the hydrogen, even though that was the major fire fuel. The theory is that the protective coating on the outer surface allowed a buildup of static, and the outer coating actually ignited first.
I don't know how much is theory:
What Bain found has led him to point to the coating on the Hindenburg's covering as the fatal flaw, rather than the hydrogen tanks. He said the covering, or envelope as it was called, had a butyl-based coating that was nonconductive, so when the electrical charge built up on the outside of the ship, it didn’t dissipate as it should have. That day, the electrical charge was greater because the Hindenburg was coming in for a higher landing than normal, Bain said. The charge ignited the fabric covering. While conducting research in Germany, Bain unearthed documents that support the coating theory. A 1937 letter from the Zeppelin company to the paint manufacturer expressed concerns, noting that tests showed the covering was “readily ignited by an electrostatic discharge.” Also testing in Germany in 1938 by the Wireless Telegraph and Atmospheric Electrical Experimental Station found the cause was “the poor conductivity of the aluminum paint coating on the outer skin.”
What Bain found has led him to point to the coating on the Hindenburg's covering as the fatal flaw, rather than the hydrogen tanks. He said the covering, or envelope as it was called, had a butyl-based coating that was nonconductive, so when the electrical charge built up on the outside of the ship, it didn’t dissipate as it should have. That day, the electrical charge was greater because the Hindenburg was coming in for a higher landing than normal, Bain said. The charge ignited the fabric covering.
While conducting research in Germany, Bain unearthed documents that support the coating theory. A 1937 letter from the Zeppelin company to the paint manufacturer expressed concerns, noting that tests showed the covering was “readily ignited by an electrostatic discharge.” Also testing in Germany in 1938 by the Wireless Telegraph and Atmospheric Electrical Experimental Station found the cause was “the poor conductivity of the aluminum paint coating on the outer skin.”
https://www.floridatoday.com/story/news/2017/05/04/what-caused-hindenburg-fire-retired-nasa-expert-digs/101153648/
Interesting reading.
York1 John
The theoretical Hyundai 'car' and the iLINT are both operating the same way: combining hydrogen and oxygen in a fuel cell to generate electron flow (which becomes traction current). If the diagram in the article confuses you, google 'SOFC' for better explanations.
It is not necessary to use the hydrogen in a fuel cell; it will happily burn directly and produce some of the highest combustion temperatures. BMW went so far as to build a hydrogen-fueled version of one of their V12s (and not incidentally figure out a 'first best use' for an early fuel cell by using it for the car's electrical loads, retaining the full power of the combustion engine for traction, as in the Budd SPV2000 railcars). But with the advent of practical high-energy-density battery chemistry and practical BEVs and plug-in hybrids, the use of hydrogen efficiently if a bit more slowly in fuel cells is now the priority.
Incidentally, hydrogen is an example of a 'carrier fuel'; it costs more to make and provide the hydrogen than you could 'sell it for' in terms of equivalents in other fuels, particularly 'fossil' natural gas or petroleum (both of which derive much of their energy from the bound hydrogen they contain). One of the chief 'selling points' is that the hydrogen is 'carbon free' and combusts to 'harmless water' at the point of consumption ... both of which are true. I think of this as a more sophisticated version of using a fuel like LPG in a warehouse forklift, where a gasoline or Diesel engine would produce dangerous exhaust. Some of the technical accounts of the Coradia iLINT go correctly into the importance of setting up the 'right' hydrogen production and sourcing infrastructure to make the 'hydrogen-burning' railcar (actually a battery-electric with hydrogen-fueled recharge) a practical proposition even when government-subsidized.
The fist practical thermonuclear device used deuterium (hydrogen with 2 neutrons in its nucleus) and tritium (with 3) at cryogenic-liquid temperature. (Neither of those isotopes is present to a more than infinitesimal degree in materials from which practical hydrogen fuel is produced; in fact the tritium has to be produced in special reactors and has a half-life of [edit: ignore previous value]12.32 years, so would have to continue to be expensively made even if not used.) Getting these to fuse in the nuclear sense does, as noted, require the temperature and pressure characteristic of a fission device to obtain a prompt yield. But you can relatively easily demonstrate small-scale fusion on a desktop -- just not extract more useful power from the fusion reaction than you had to put in to produce the fusion power out. (An associated issue for fusion generation is how the power comes out. If much of it is gamma radiation, that's nifty for a weapon, but much more difficult to capture and use for a purpose like electrical generation; if it comes out as neutrons, the situation is worse. What you want are charged particles, including beta particles (which act like electrons) which can be used to induce electricity in tuned 'antennae' (google 'mirror machine' for one configuration, which in the '70s had the promise with the 'right' nuclear reaction to produce DC electricity up to something like 93% of the nuclear yield without either excessive gamma shine or neutron activation. At least theoretically such a thing could be built at the scsle of Bussard's Riggatron, which is not quite road-vehicle size but certainly something that could be used at railroad scale. (The French of course perfected nuclear-powered train designs decades ago ... they use ground-based reactors to make grid power, part of which easily feeds TGVs...
It might be noted in passing that a number of hydrogen carrier-fuel schemes have proposed to use nuclear reactor heat to produce fuel hydrogen -- it's lavish and cheap and can't be used to produce effective steam superheat at high pressure safely for the Rankine cycle, so assuming you have a secure nuclear fuel cycle, an established hydrogen cycle, and the political capital and will to 'get there' the actual perceived marginal cost of the carrier fuel may actually look reasonable...
The problem with the lay association of 'hydrogen' (a technical-sounding word used to inspire fear in the unwary, not unlike the marketing adoption of 'sodium' in food ratings) with bombs is that hydrogen does have considerable explosion potential, and its high energy content implies that even with the awful fuel density in practice you can get some pretty good critical-mixture bangs out of it. In fact the flammability (and I think explosive in confined space) limits of hydrogen in air are something like 4 to 75%, not exactly a confidence-inspiring range for large numbers of perhaps poorly-maintained cars in, say, underground garages under buildings. (As another great taste in this candy bar, hydrogen flame is basically invisible; the way it was tested in flare off at the Ivy Mike test was to hold up a broom to see where it ignited.)
I did my college junior project on popular news coverage of the accident at TMI (one of the initial Times stories featured a dramatic picture of hyperbolic cooling towers venting huge plumes, with the headline underneath 'ACCIDENT AT NUCLEAR PLANT IN PENNSYLVANIA, RADIOACTIVE STEAM IS RELEASED'). Those who remember the unfolding saga, recently recalled in another post on a Kalmbach forum, will remember the tale of the hydrogen bubble and the risk that it would 'explode' and thereby release 'huge amounts of radiation' or facilitate a meltdown. (In fact the situation was worse than recognized in the latter respect; my recollection is that the engineers thought the hydrogen was from dissociation of water and not reaction of zirconium cladding ... in part because actual cladding failure was supposed to have far more dramatic consequences than were bring observed ... but this is peripheral to the way newsworkers seemed to delight in conflating 'hydrogen explosion' from critical mixture in the top of the containment eith 'hydrogen explosion' in megaton weapons.
A couple of decades ago, someone who I recall as working at NASA pointed out that the entire fabric skin of the Hindenburg was primed with red iron oxide, then coated with aluminum paint. That combination of materials in proximity to a high-energy combustion heat source should be raising the hair on the back of your neck to contemplate. While I think some of this has been 'walked back' subsequently, like the effect of the sulfur content in Titanic's rivet iron, the likely consequences of a large-surface-area Goldschmidt reaction are not something delightful to contemplate where human lives are involved.
A couple of points:
The flammable skin theory for the Hindenberg has been de-bunked, pictures show clear evidence of a hydrogen fire. Having said that, it is quite possible that a fire on the skin ignited the hydrogen in the gas cells.
Deuterium is composed of 1 proton and 1 neutron, natural abundance is 0.015%. Tritium is composed of 1 proton and 2 neutrons, and is a beta emitter with 18.5keV end point energy and 12.5 yr half life. Most common production method is irradiating Lithium with neutrons.
Back in 2014, I did get a ride in a hydrogen fuel cell powered Rav-4, seemed to have adequate performance.
Thanks to Chris / CopCarSS for my avatar.
Murphy SidingYeah! Stairway to heaven rocked!
Was that the tune sung by Led Hindenbergs?
Didn't the Hindenburg pass through a thunderstorm and had to delay its landing at Lakehurst? The theory I've read is that it was jazzed up with static electricity and was grounded by the first mooring rope that was dropped.
Those guys on Mythbusters made a model of the Hindenburg and proved that it was a hydrogen fire and that the outer coating was not a factor. I might be remembering it wrong, but damn, those guys have a lot of fun! Once during Thanksgiving my mother had a small tv in the kitchen tuned to the Macy's parade. She said that there seemd to be a problem with one of the balloons. I said that the hydrogen ignited in the balloon and didn't you hear the guy yell about the humanity? My old man sprayed his coffee all over the table.
The Graf Zeppelin never had an accident in its long career and I sure would have liked to travel on a zeppelin. From what I've seen it was like an airborne Pullman car.
When I first got involved in USAF weather, I worked with weather balloons. While USAF chiefly used helium to fill the balloons (and still does), they did have available hydrogen generators that used anhydrous ammonia as the input. The ammonia was cracked in a retort using heat and platinum(?), producing hydrogen suitable for the use.
I never used hydrogen in a weather balloon, but I did hear stories of balloons lighting off as they were being filled. Weather balloons are made of pure latex.
While I was stationed in CA, an accident occurred at an industrial facility in Lompoc involving hydrogen in compressed gas cylinders. I never heard full details, but a man was killed.
Way back in HS chemistry, we made hydrogen - don't ask me how because I don't remember. What I do recall was that we stretched glass tubing to make nozzles to flare the hydrogen. The fire was so hot that it usually closed off the nozzle...
Erik_MagThe flammable skin theory for the Hindenberg has been de-bunked, pictures show clear evidence of a hydrogen fire.
Take this simple test: Enclose an enormous amount of diatomic hydrogen in thin-walled bags of organic material. Then put a thin shell of thermite around it. Light the thermite and follow the resulting TWO ASYNCHRONOUS processes to their logical conclusion.
Hint to the unconvinced: Hydrogen fires are transparent or blue, depending on bonding energy. Thermite is luminous broad-spectrum. Note the type of fire observed in the newsreel pictures ... and the shape of its propagation. I also note very little evidence of a critical-mixture explosion of any kind. There were survivors of the Hindenburg disaster. From a hydrogen explosion there would have been few or none.
One of those mythbusting shows was trying to produce a carbureted critical-mixture explosion with an electric spark, and couldn't get the trick to work as they turned the current up and up and just couldn't get the darn thing to light. Then they thought to put a little piece of paper in the spark as a longer-term flameholder, and got their reliable light-off every time. This was enough indication of the 'thermite connection' FOR IGNITION to convince me. Of course once you had a nice hot hole burned in the envelope with nifty incandescent reduced iron dribbling through to the cells, you can expect the hydrogen to enthusiastically take up the tune, and bring large areas of the envelope up to Goldschmidt-reaction temperature... including 'en masse' over large areas 'from the inside' as air convects into burned-through cells and "heat rises". Which i think you see in the newsreel footage once you know there are two heat-release processes going.
Deuterium is composed of 1 proton and 1 neutron, natural abundance is 0.015%. Tritium is composed of 1 proton and 2 neutrons...
You will note that i said 'hydrogen with two and three neutrons in the nucleus' which not only accomplishes the same result but does not make the mistake you did of ignoring the electron. If you ionize that away, you have protons, deuterons, and tritons respectively.
And technically you can't 'irradiate' anything by using particles, especially not neutral ones. The term of art used to be 'bombard'. That was decades ago. Yes, I know the NRC and other agencies officially use 'irradiate' ... but even large numbers of experts using the term doesn't make it semantically correct.
"SMACK! on the missile goes the ion beam!" (In the slightly upgraded version of the song.)
I did get a ride in a hydrogen fuel cell powered Rav-4, seemed to have adequate performance.
The point being that vacuum-brake cylinders are much larger than air-brake cylinders (as their highest actuation pressure without mechanical advantage will never be more than 15psi). Shrewd perfidious-Albion types oversized the cylinders, banking on the idea that non-engineers would not recognize just how much bigger they actually were.
Thus it is with larger fuel-cells and quick-releasing hydrogen storage, right up into the range you can generate enough current to approximate Ludicrous++ mode in your traction equipment without any supercap or battery storage. Problem is, just as putting a dual-quad Paxton-blown side-oiler 427 in your car, all that cell architecture and all that hydride takes up money, space, and weight (which are traditionally factors keeping hydrogen adoption to larger vehicles or specialized and often government-subsidized uses)
In a combustion engine hydrogen is a wonder fuel, except that the high heat release limits how effectively you make the power expansion in a combustion engine work. A good fuel cell can get around this sort of limitation more effectively, and once you have the 'transmission infrastructure' for charging a suitable Tesla-style battery bank (and charge management via transfer to supercaps, etc.) It makes better sense (at least it does for me), just as with a Karman hydraulic-accumulator transmission, to make the 'sustainer' engine no bigger than that which just keeps the transmission 'charged' steady-state at highest service output. It is interesting just how small an engine, and how interestingly tuned it can be, for a 7800lb vehicle required to run a steady 65mph up the steepest highway grades in California... this seems to carry over into iLINT and use of fuel cells instead of gensets to produce charging current.
My understanding is that the biggest thermo-neuclar explosions used lithium. Basically it was one of three isotopes ? Wasn't it a different than normal isotope of lithium used that had an unanticipated reaction more than other isotopes. That almost caused the death of observers at one of the Bikini tests ?
The Castle series of tests were the first ones using lithium deuteride as opposed to the cryogenic deuterium and tritium used in Ivy Mike. IIRC, Lithium 6 was considered to be the active nuclide versus Lithium 7 (Li6 + n -> He4 + T) and the expected yield for Castle Bravo test was 3-4MT. In reality, Lithium 7 was also fairly active and yield ended up around 15MT.The increase over expected yield did cause a lot of "pucker factor" in the observers.
The device had a depleted uranium casing to increase explosive yield as the fast neutrons from the fusion reactions would induce fissions in U238 leading to about a third of a ton of fission products being produced (AKA Fallout). The prevailing winds blew the fallout over a Japanese fishing vessel, with one of the crew members dying from acute radiation poisoning.
blue streak 1My understanding is that the biggest thermonuclear explosions used lithium.
The original 'proof-of-concept' Sausage (used in the Ivy Mike shot) device used cryogenic D-T and was initially scheduled to be weaponized as 'Jughead' (considerable interesting work on cryo logistics for such a weapon being done, including the internal thermal shields). The much better idea of a 'dry bomb' using enriched-with-lithium-6 lithium deuteride (i.e. a hydride using heavy hydrogen) was developed for a couple of Castle shots: this got the necessary fusion-fuel density without a phase change or the fun involved with liquid hydrogen. (The lithium-6 fissions to helium and tritium, the latter fusing with the 'hydrided' deuterium with 17.6MeV yield)
Now it turns out that there are a couple of reactions with lithium-7 (which is about 92.5% on average of naturally-occurring lithium) that with sufficiently dense neutron flux also produce tritium. Which will then happily fuse just as that from lithium-6 does... with the lavish flood of neutrons then producing substantial fission yield from the depleted-uranium tamper.
The initial 'Shrimp' device fired as Castle Bravo used lithium enriched to about 40% Li-6. When fired it appropriately 'ran away' to more than its predicted yield range. More interesting is the 'Runt' device which used 'natural' lithium in a larger amount (remember that 7.5%?) which also ran away to greater yield, much of which was tamper fission. It should be noted that substantial heavy-element generation was also produced in the uranium by capture of large amounts of neutron flux from the fusion reaction. Much of the radiation in the fallout plume was from the fission products, not just activation of calcium and other debris from the explosion.
Interestingly, there was a version of the 'Runt' device made with the same ~40% enrichment as 'Shrimp'. You'd think that the high yield of the natural version would indicate there was no need for more runaway-reaction demonstrations in a more-enriched version of the same device configuration ... but you wouldn't be right. They went right ahead and fired it (as Castle Yankee - these tests still used the military alphabet for the sequential test numbering) with perfectly predictable results. Now this was the EC24 configuration for which I believe the "Solvex" (more properly COLEX) process was built out as production enrichment in quantity, and as a weaponized system there was some justification to see 'what it would actually do'.
BTW, this is not the Bikini testing most people associate with the name (and the end-of-the-world swimsuit) in 1947 (Crossroads). I wonder if you're thinking of Redwing Cherokee (in 1956) which was an air-drop test detonated 4 miles off intended target. There was certainly plenty of fallout from Bravo and the the other 'runaways' -- Bravo being the thing that first put fallout 'on the map' as the most serious consequence of using large-yield Supers -- and this certainly caused issues both at Bikini and further away (remember the Fortunate/Lucky Dragon) -- but most of this was not reported as being immediately dangerous to military observers. Had the plume from Bravo tracked even a little further south, the outcome might been quite different.
Quoting Larry "Way back in HS chemistry, we made hydrogen - don't ask me how because I don't remember." We released hydrogen by dropping mossy zinc into hydrochloric acid. I don't remember what we did with the hydrogen--let it dissipate into the atmosphere?
A couple years back, probably during the last gas price spike, talk of hydrogen powered cars was all the rage. The hype seemed to be that scientists and inventors were on the verge of replacing gasoline with a fuel that only costs pennies per gallon. What happened to that idea?
Deggesty Quoting Larry "Way back in HS chemistry, we made hydrogen - don't ask me how because I don't remember." We released hydrogen by dropping mossy zinc into hydrochloric acid. I don't remember what we did with the hydrogen--let it dissipate into the atmosphere?
I recall setting up that reaction in sophomore chemistry. We would capture the hydrogen in a test tube and burn it by putting the mouth of the test tube near a Bunsen burner. Some of us made bigger bangs by using larger containers.
Thought the easiest way to make hydrogen was electrolysis. That is the way we did in HS. That method does not pass the smell test for being energy efficient.
blue streak 1Thought the easiest way to make hydrogen was electrolysis.
Note that the objective 'in the field' is to release large volumes of diatomic hydrogen gas quickly, from relatively safe precursors and low-tech passive equipment. And to use it directly as a lift gas, displacing air, rather than as a high-energy propellant or effective carrier fuel.
That will tell you that starting with water, production of which is one of the most exothermic reactions known, to get all the way to monoatomic hydrogens before they recombine, is not the happiest solution. What you want instead is large amounts of something with comparatively low bonding energy, with nothing else around that is likely to react with the hydrogen when those bonds are broken, leaving nothing that either dilutes or compromises the hydrogen as a lift gas.
Ammonia is relatively nifty here as it produces three moles of hydrogen for every mole of (much denser) nitrogen -- and if you can fix that nitrogen in some way that does not contaminate or diffuse into the hydrogen, you're further ahead of the game. Now split the NH3 with a catalyst and you can get speed of dissociation without much risk of poisoning the catalyst ... a bit like obtaining oxygen by catalyzed decomposition of H2O2 in the Oxford Catalysts direct-steam system.
You could add some copper sulfate to speed up the reaction. They you capture the hydrogen in a ballon, tie it off, tape it to a yard stick, run down to the front office of the school and explode the thing.
We thought it was fun. The assistant principal less so. It was summer school and we had volunteered to take chemistry to get ahead a bit, so "don't do that again" was it.
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
blue streak 1 Thought the easiest way to make hydrogen was electrolysis. That is the way we did in HS. That method does not pass the smell test for being energy efficient.
That's also what we did.
Then, a glowing splint put into the oxygen tube glowed brightly, and the glowing splint put into the hydrogen tube made a whistling sound as the hydrogen burned in the tube.
We did slightly different things at my high school. One of them (which I confess spurred my initial interest in methane LTA) was, conveniently enough, 'Hindenburgs' while cleaning up glassware -- run the hose of a Bunsen burner into soapy water, then light the foam sausage as it starts to rise. Rings of fire across the ceiling mark the standing waves in the heated column -- we have movement in three directions, this is very scientific, as the Waitresses sang. Another methane classic was the drawer experiment, made possible because the support rod sockets for apparatus went right through the slate bench tops into drawers above the glassware cabinets. It was the work of a few monents to fill the drawer from the handy gas hose, then light the gas above one or more of the sockets. Wait for the flame to die down and disappear, then engage some hapless classmate in conversation with their rump toward the drawer until the critical-mixture deflagration made a satisfying puff... this worked nicely for a while until successive pressure excursions weakened one of the drawer fronts and blew it off.
The whistling reminded me of one of those indelible karma moments. One student discovered that filling a 500ml graduated cylinder would produce the pitch-changing whistling noise. He got excited, named the experiment the 'Whistler, and repeated it a couple of times. Then he picked it up and the vibrations had neatly separated the glass right at the junction between cylindrical wall and base. I cannot recall a look more steeped in betrayed sadness than I saw at that moment...
Why not extract the hydrogen from natural gas? It would be less expensive then using extrolysis to obtain it from water. We have so much natural gas that we do not have any place to store it.
Caldreamer
Or maybe...
caldreamerWhy not extract the hydrogen from natural gas?
ok. you cannot drink it. ther are many industrial uses for methanol, but you can easily get methanol from wood chips, erc.
caldreamer ok. you cannot drink it. ther are many industrial uses for methanol, but you can easily get methanol from wood chips, erc.
You are correct. It can also kill you. BTW: I should have said that you can manufacture methanol from any cellulose based material not just wood chips.
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