http://bravenewclimate.files.wordpress.com/2011/10/nuclear-ammonia-2011-sendrev.pdf
Even if the rest is rubbish, it mentions the beloved LFTR so dear to Prince's heart!
What?![]()
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http://bravenewclimate.files.wordpress.com/2011/10/nuclear-ammonia-2011-sendrev.pdf
Even if the rest is rubbish, it mentions the beloved LFTR so dear to Prince's heart!
What?![]()
I'm not understanding why they made their power point presentation about Ammonia instead of Methanol??????
Going down the list, Methanol has all the same advantages as Ammonia, except it's not nearly as toxic. The article even directly states that the energy density of Ammonia and Methanol is the same (about 1/2 that of gasoline). Ammonia is a deadly gas if you inhale it. On the other hand, Methanol is actually safer than gasoline. It's burn rate makes it less likely to catch on fire, and a number of racing sports actually require it to be used in the competing cars because of that safety difference. . Just like Ammonia, Methanol will burn in a standard gasoline engine. Also probably requires less modification to do so, as the only change is to make sure certain metals aren't used (such as aluminum).
Methanol - Wikipedia, the free encyclopedia
Both can be synthesized from water, air, and electricity. The only difference is that with Methanol you take the CO2 from the air, instead of the Nitrogen.
Was hoping you would comment.
Objections are appreciated, and of course, LFTR can provide electricity as well for one as the other. Of course, for railways, intervening chemical fuel can be eliminated altogether in favor of electrical propulsion, in a nuclear future it only makes sense to visualize a greater role for railways, already more efficient than roads. No reason ships cannot use reactors for power either as evidenced by numerous present-day naval vessels.
Is the age of chemical fuels coming to an end, in fact, whether "synthetic" or geologically derived?
If we're talking about boats, then (I hate to say this but) boats with nuclear power plants onboard manufacturing CH4 or Methanol might be a better option than the solar barges I was talking about in the solar thread. Probably people would be a lot less concerned about the safety if the power plant is located in the middle of the Pacific, where you can just sink it if there's a meltdown (and the sea will probably be able to absorb everything.... for one or two melt downs anyway.) It might even be possible to use re-processed nuclear waste as fuel with all that added safety.
The advantage of chemical fuels is that you have very little transmission loss, if any, as well as the potential for long term storage. The only transmission cost is transporting it, and the only storage concern is building a fuel tank big enough to hold it all.
If we really want to destroy OPEC's hold on our economy (and the world's), the best way to do it is to simply stockpile so much synthetic fuel that OPEC is forced to keep its prices constant out of fear of being undercut. They can't suddenly stop selling and create another oil crisis of trillions of gallons of Methanol are sitting there waiting to fill the gap.
Again a keen observation- after all, petroleum and coal have very effectively stored energy for appreciable periods of geologic time. Still, ocean-going vessels are remote locations, usually, and would benefit from a power source which is unaffected by various latitudes and weather conditions they must encounter, and one source of concentrated power, allowing maximum room for payload, would be nuclear.
Most nuclear "waste" by volume, is depleted uranium which could be put to good use in breeder reactors- however, to best knowledge of your royal correspondent, breeders have not been adopted for maritime use.
Nuclear Merchant Ships
It is looking like NH3 is selected because of existing infrastructure and greater hydrogen derived energy density.
More at: Why NH3?
Now I get why they like it so much.
They're cheating. Methanol produces CO2 when it burns, but.... it also removes an exactly identical amount of CO2 when it is made (if it's made by synthesis rather than cracking other hydrocarbons)... Really Methanol and NH3 are on an equal footing here.Originally Posted by Prince's Link
However, Methanol clearly wins the safety contest. NH3 has to be pressurized to ~125 PSI in order to achieve an energy per volume equal to 1/2 that of gasoline. Methanol has that at normal atmospheric pressure. And unlike NH3, which can kill you if you inhale it, Methanol is only toxic if you try to drink it (in which case you will go blind and maybe even die.)
I don't know about the relative cheapness though. I'll have to look into it some more.
And this part is certainly an advantage (unless they're just saying it can be synthesized... which is true for both it and Methanol anyway.)NH3 is Low Cost
- Comparable to or lower in price than gasoline on an equal energy basis
- NH3 produced using renewable or nuclear source electricity will be stable in price and increasingly cheaper, per BTU, than fossil based fuels.
Can be produced cleanly from coal and natural gas with carbon sequestration, and also from biomass, renewable energy sources and nuclear power, using nitrogen from the air
Nitrogen oxides are greenhouse gases and are produced when ammonia is burned. There are treatment methods of various efficacies but it is simply false to say no greenhouse gases are produced on combustion of NH3.
Methanol is usually produced from a fossil fuel carbon source - coal or natural gas. The CO2 produced when it burns is the same CO2 that the coal or methane would have produced, but you have had an additional processing step that consumes energy at some stage.They're cheating. Methanol produces CO2 when it burns, but.... it also removes an exactly identical amount of CO2 when it is made (if it's made by synthesis rather than cracking other hydrocarbons)... Really Methanol and NH3 are on an equal footing here.
The main problem with capitalism in general. There's no way to get private companies to use any method except the cheapest, unless you force them with regulation, and then they send their lobbyists to Washington to undo it.
You're right that methanol is usually produced from fossil fuels, but it doesn't have to be. It just is because we live in a messed up system.
Not the cheapest - the ones with short term profit potential. Investors mostly will not invest in technologies that might produce profit 20 years down the road, even if these technologies might save the planet from disaster. Fortunately there are publicly owned laboratories that will do this sort of work and that spin off their technology for private firms to profit from - after the risky, expensive preliminary work has been funded by the taxpayer. One example id the National Renewable Energy Laboratory in Golden, CO. Their latest success is reported here: New GE Plant to Produce Thin Film PV Solar Panels Based on NREL Technology | Department of Energy
Another government lab, the NETL, is developing a flameless combustion technology that may or may not succeed - I'm a bit skeptical but it's a small price the taxpayer is paying to find out. Yet anothet technology, membrane hydrogen separation, is being developed by some European consortia with EU funds. The US firms that think they have better technology than the Europeans have to rely on government funding and as far as I know are making good progress.
You cannot make methanol without a carbon source. If you are referring to pulling CO2 from the air then, yes, it's theoretically feasible but what is the practicality of that? Is it not being done because private investors won't pay for it or is it not being done because there is no technology even in an inventor's mind that can economically get sufficient amounts of CO2 out of the atmosphere? These are not rhetorical questions. I'm interested in what you know about this.You're right that methanol is usually produced from fossil fuels, but it doesn't have to be. It just is because we live in a messed up system.
Combustion energy is obsolete, anyway, but Prince is aware of MagnetoHydroDynamic (MHD) potential technology, where flame serves in place of rotating magnet in generator. Probably deserves own thread if one does not exist already.
Commercial quantities of "dry ice" carbon dioxide are extracted from atmosphere for frivolous drink carbonation and other purposes. Should not be a problem but of course further investigation may prove otherwise.
According to George Olah, one of the two guys who co-invented the direct electric Methanol Fuel cell, he sort of cryptically said that you can "reverse the process" in an interview here. He's a Nobel Prize laureate (1994 Nobel Prize in chemistry), so I doubt he'd just make something like that up.
The Methanol Economy - Technology Review
The other way is to use a process called the Reverse Water Shift Gas Reaction, to create CO from Hydrogen and CO2, then react the CO with Hydrogen again to create methanol. CO + H is the same thing as the "Synthesis Gas" that is created by incompletely burning Natural Gas.Originally Posted by George Olah in an interview
Reverse Water-Gas Shift Reaction - Marspedia
I haven't really researched how the most economic ways are to find or acquire pure CO2, though. It's funny to think that we're surrounded by it, but it's actually a hassle to get it in its pure state.
Originally Posted by George Olah in an interview
We have known how to do this for decades but it's energy-intensive and capital intensive.
But eventually, and this won't come overnight, we could just take out carbon dioxide from air
Seventeen years later, how are we doing?
The concentration in the atmosphere is sufficient to cause climate change but not sufficient for economical extraction.I haven't really researched how the most economic ways are to find or acquire pure CO2, though. It's funny to think that we're surrounded by it, but it's actually a hassle to get it in its pure state.
I would say there are exceptions to that. They will develop the theoretical technology, test it, and patent it for the future. Sure, its not profitable in the here and now, so they won't implement it. But... they will have the patents for future use. They can allow others to use their patents and be paid for it.
I would say that when the government has to spend money to help induce a new technology, either the government has use for it, or it shouldn't be done unless we are running a budget surplus. Venture capitalists will fund projects they see likely payoffs on. When we are near the point that the new technology has a payoff, there will be plenty willing to fund these.
You think the government should have stayed out of this?GE’s plans to drastically increase PrimeStar’s production capacity place its solar business in a field with other Department of Energy PV Incubator alumni such as Abound Solar and Solopower. Within the next few years, all three companies will be producing solar thin film PV modules at large commercial scale in the U.S. – and all will be doing it thanks to American innovations made possible by the Department’s sustained investment in solar energy R&D.
Where were the venture capitalists for this thin film technology? If they were there at all it was in partnership with the DOE through NREL.Venture capitalists will fund projects they see likely payoffs on.
Obviously. Once we the taxpayers have reduced the risk for them.When we are near the point that the new technology has a payoff, there will be plenty willing to fund these.
What do you think about these synthetic carbon sequestration trees? Any potential to get CO2 out of those?
Scrubbing CO2 With Synthetic Trees - NYTimes.com
Synthetic Trees Could Be Environmental CO2 Scrubbers | greenUPGRADER
The second link describes them working by reacting Sodium Hydroxide (NaOH) to create Sodium Carbonate (Na2CO3). I don't know how easy/hard it would be to liberate the CO2 from that. Maybe not practical at all?
The only exception, I'd say, to that rule, is if mineral costs are the dominant cost for the cheaper product, and labor costs are the dominant cost for the more expensive one.
Imagine (this is just made up numbers to try and explain the concept I'm describing) if the price of oil is $4.00 a gallon, and suppose that $$2.50 of that were all in mineral rights. The remaining $1.50 was paid in labor.
Now imagine 2 gallons of Methanol cost $5.00 a gallon (it takes two gallons of Methanol to deliver the same energy as 1 gallon of gasoline). But suppose $4.00 of that was all labor.
In this case, the cost to the consumer per gallon went up by $1.00, but the wages paid out to workers per gallon went up by $2.50. When that money recirculates through the economy we'll all see our standard of living to have raised.
Prince will both elucidate AND elaborate: He was wrong. Naively assuming that CO2 was a component derived from liquid air he stated the above- evidently volume of same being trivial in air, it is regarded more as a contaminant and is instead derived mostly from methane and carbonate rocks, thank you for allowing him to clarify, dotcomrades.
In any case, production of synthetic chemical fuels requires power derived from another source. Nuclear can produce not only electrical power in mass quantities but also high grade industrial process heat sufficient for thermal hydrolysis and the Haber process of producing ammonia, 300* to 550* C. This is something solar cannot readily do in the terrestrial setting.
Or is Prince mistaken once again?
Will tune in tomorrow to find out, best regards until that happy time.![]()
Last edited by The Finger Prince; October 30th, 2011 at 01:54 PM.
Now you've got me curious, Prince. I wonder what the actual efficiency is. Will have to look it up. Ammonia will never be practical as automobile fuel because of safety concerns, but if it can be produced at a minimal loss, and then reconverted to electricity also at a minimal loss then it might have some real potential for long distance energy transport/storage.
I still don't know about using nuclear to make it, though. With nuclear you don't need storage anyway. It's already a base loading technology.
Looking into the Haber Bosch process, it's poignant to note that the problem of how to extract Nitrogen from the air is not an issue for Ammonia like the problem of how to extract CO2 from the air appears to be for CH4.
http://en.wikipedia.org/wiki/Haber-Bosch
Despite the fact that 78.1% of the air we breathe is nitrogen, the gas is relatively unavailable because it is so unreactive: nitrogen molecules are held together by strong triple bonds. It was not until the early 20th century that the Haber process was developed to harness the atmospheric abundance of nitrogen to create ammonia, ...
Last edited by kojax; October 31st, 2011 at 08:54 AM.
I've got 286 KJ/mol as the energy released by combusting H2.
I've got 382.81 KJ/Mol as the energy released by combusting NH3.
I've got 92.22 KJ/Mol as the energy consumed to convert Hydrogen and Nitrogen into NH3.
286/2 = 143 per H atom.
382.81/3 = 127.6 per H atom
92.22/3 = 30.74 per H atom
127.6 - 30.74 = 96.86
96.86/143 = 67%
That last number should be the efficiency of converting H2 into NH3 before burning it if I'm reading everything right. However, I might be misreading some things. I'm sorry. I'm not good at reading chemistry formulas right. Maybe that was 92.22 kj that gets released when Hydrogen is converted to Ammonia, instead of being consumed? Hopefully someone can clear that up. The links to the formulas are these. I'd really like to try and get a clear picture of what our efficiencies of conversion are if I can.
Hydrogen - Wikipedia, the free encyclopedia-Combustion formula
Ammonia - Wikipedia, the free encyclopedia-Combustion formula
Haber process - Wikipedia, the free encyclopedia- Chemical process formula.
The ammonia synthesis reaction is exothermic, which is why there is a minus sign in front of the 92.2KJ/mole, meaning that heat is released, not absorbed.
The heating values you give for hydrogen and ammonia are correct, but they are the higher heating values (HHV). In an internal combustion engine the water vapor produced is not condensed so you should be using the lower heating value (LHV). For hydrogen this is about 242KJ/mole and for ammonia is 316KJ/mole.
In considering the energy required to convert hydrogen into ammonia you ought to include all the process energy ins and outs as well as the basic chemical reaction energy; for instance compressor power for the air compressor and the hydrogen compressor, the heat recovered in the ammonia converter waste heat boiler, and the heat lost to the cooling tower from the ammonia product cooler. There are many others and it's not really feasible to do this calculation quickly on a bulletin board.
On the plus side, it is theoretically possible to improve the efficiency of an ammonia combustion engine by using the liquid ammonia as an engine coolant and as refrigerant for the AC system. I don't know how practical this is.
As to hazards of ammonia, granted, but gasoline is known to be carcinogenic as well as explosive, so weigh in elimination of these hazards, commonly dealt with everyday. Thanks to all for illuminating comments.
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