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Ammonia—a renewable fuel made from sun, air, and water—could power the globe without carbon 4

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cmoreride

Civil/Environmental
Jun 30, 2019
53
Ammonia—one nitrogen atom bonded to three hydrogen atoms—may not seem like an ideal fuel: The chemical, used in household cleaners, smells foul and is toxic. But its energy density by volume is nearly double that of liquid hydrogen—its primary competitor as a green alternative fuel—and it is easier to ship and distribute. "You can store it, ship it, burn it, and convert it back into hydrogen and nitrogen,"

 
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Yes this is interesting. It doesn't get around the problem of getting the hydrogen in the first place, and it seems like a rather energy intensive process, but the result is certainly easier to transport and store than LH2. I do wonder about using it as a combustion fuel, the NOx emissions will be substantial, locally. But if the numbers add up, it makes long range flight more viable than batteries or LH2.


Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
burning H2 produces H20, yes?

water vapour is a much stronger greenhouse gas than CO2.

another day in paradise, or is paradise one day closer ?
 
rb1957: water IS the most important greenhouse gas. But water VAPOUR emissions aren't a GHG emission concern unless they are emitted in the upper atmosphere where they form contrails.

Water vapour is in rapid physical equilibrium with water liquid in the oceans and biosphere.
 
cmoreride: ammonia is made from hydrogen. Hydrogen, a 120 million tonne per year industrial gas (between pure H2 and H2 in syngas), is 98.7% made from fossils (methane, coal and petroleum) WITHOUT carbon capture.

Until the massive problem of the decarbonization OF hydrogen production is actually tackled- and so far it hasn't been to any appreciable extent - any plan to burn ammonia is basically energetic vandalism.
 
The Australian government is using my money to fund a couple of hydrogen from solar and water projects. I know one of the researchers on this and he is, hmm, enthusiastic and thinks the idea is sound, but that's his job.

A slight problem is that once you've got the hydrogen you then have to get it to where it is needed, and that's where the ammonia process starts to look attractive for these remote plants. Rather than expending 1/6 of the calorific value of the hydrogen liquefying it, 'just' turn it into a usable and easily transportable liquid.



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
Sounds promising.

I've been saying to anyone who will listen is that 'time-unreliable' energy sources like wind and power should be used for powering processes like this that produce high energy density, readily transportable fuels. Energy storage has been the Achille's heel of renewables, and in this case, ammonia effectively becomes an energy storage medium.

Safety will always be a significant issue for ammonia though, as anyone familiar with ice rink refrigeration failures can tell you.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
 
My two cents ...

I think that it is important to call this hydrogen transport medium "anhydrous ammonia" which is the proper name...

Secondly, it is important to recognize the unique transportation and storage hazards of anhydrous ammonia. There is a special type of cracking induced into carbon steel when in long term contact with AA. Also, storage of AA usually is at 250 psig which implies large, thick pressure vessels and piping

Thirdly, unless you want to have a massive number of trucks or railcars transporting large quantities of this stuff, then the new hydrogen economy is not going to happen. ..... That leads us into the only practical solution ... AA pipelines !!!

Recall that the current administration is against underground pipelines ..... but only the pipelines that transport "bad" things, like petrochemicals ..... not the pipelines that may transport "good" things .... in support of the vision of the new economy

Lastly, if you want to see a real environmental mess, break into a high pressure AA pipeline. Its at least as hazardous as any crude oil transport pipeline..... IMHO

Will the anhydrous ammonia lobby be advocating a new system of pipelines ?????

Anybody else out there add anything ???

MJC



MJCronin
Sr. Process Engineer
 
MJCronin said:
Anybody else out there add anything ???

Yes. The only mitigations of any lasting value are to build fewer vehicles, build fewer highways, but above all, have fewer offspring, which is a multiplying factor on 'all of the above'.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
 
MJCronin said:
Its at least as hazardous as any crude oil transport pipeline

I think I'd rather have a crude spill. AA has an IDLH of something like 300 ppm. At least with crude I could possibly get away before it kills me. AA is also exothermic in water, so there is that added bonus if there is a spill.

Andrew H.
 
I'd rather we weaned ourselves off of millions of years old decayed and toxic biomass, and quickly.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
 
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