Comment by dizzant
2 days ago
The comments here are focused on how much energy it would take to turn this into fuel. The real story here is decentralized fertilizer production, buried at the end of the article:
> this innovation could fundamentally reshape fertilizer manufacturing by providing a more sustainable, cost-effective alternative to centralized production
The high energy cost of Haber-Bosch, plus the additional cost of transportation from manufacturer to farmer could potentially be eliminated by distributed, passive fertilizer generators scattered around in the fields.
I'm no expert, but assuming sufficient local production, low concentration could potentially be overcome by continuous fertilization with irrigation throughout the growing season.
Let's find out. Some quick fiddling with a molarity calculator and an almanac:
-- 100 uM ammonia -> 1.7 mg / L ammonia
-- 82% nitrogen -> 1.4 mg / L nitrogen
-- My lawn needs around 1 lb / 1000 sq ft, or around 5 g / m2
-- So my lawn needs about 3500 L / m2 of fertilized irrigation total for the season
-- Ballpark farming irrigation is around 0.2 inches per day, or around 5L/m2
I would need to water my lawn about 700 days in the year, or more realistically up my irrigation rate by about a factor of 4, AND source all of the water from the fertilizer box.
I'm a little skeptical that I can allocate space for enough production and still have a lawn left to fertilize. The tech probably isn't ready for the big time on an industrial farm yet, but for research demo, this seems like a promising direction! Much more than concentrating it for fuel.
Interesting idea.
So, farms are definitely setup already to accomplish this. Most farms have moved to central pivots for irrigation, and they already inject fertilizer into the pivot [1]. If fertilization could be generated onsite, then you could theoretically have everything plumbed together to "just work" without much intervention or shipping of chemicals.
[1] https://www.farmprogress.com/farming-equipment/chemical-fert...
Rain will wash nitrogen away (down to streams, rivers, and then the ocean creating lots of problems) so you want to apply nitrogen with an eye on when it will rain so your fertilizer stays on the field where you want it. Your link doesn't specify what fertilizer is being applied, I would guess nitrogen is not one.
Ammonia should be applied to the soil - in the air it is a hazard that can kill people and harm the plants (farmers wear lots of protective gear when working with ammonia, with more other things they don't bother).
As such I'm not convinced that is the right answer. You want a system that will apply nitrogen
> I would guess nitrogen is not one.
It's the main fertilizer applied.
Here's another site talking about common problems with this technique (from a farmer's perspective). [1]
[1] https://www.valleyirrigation.com/blog/valley-blog/2022/06/13...
Farmers use anhydrous ammonia that bounds with water in the soil and then bonds to the soil.
I don't know that farmers wear anything special when applying it, but there are safety procedures. I work with a farmer and he was telling me about one time he forgot to switch one of the valves off and when he disconnected a hose, the fumes knocked him out. Luckily it was just the fumes from the hose and not the whole tank or he likely would have died instead of just being knocked out.
Farmers already do keep an eye when it will rain before applying fertilisers. So, this is already part of their calculation. Although, yes , this means they will not apply it everyday. Depending on their location this means that a lot of weeks are out of the picture.
A somewhat passive fertiliser generator scattered around your fields is also known as a "cow" and a "chicken".
Cows and chickens cannot fix nitrogen from the air. They eat the nitrogen-fixing plants. So in a sense they don't "generate" fertiliser, they only concentrate it.
And distribute it across acreage.
Of course you can't have cows wandering through your corn or soybeans, they'll eat and/or crush it. But if you had fields that you could rotate between pasture and planted that could work.
Until big fertilizer lobbies to make decentralized fertilizer illegal. Insert national security, wrong hands blah blah
> Insert national security, wrong hands blah blah
That isn't a big reach.
Ammonium nitrate is already controlled in several parts of the world
https://en.wikipedia.org/wiki/ANFO
ANFO is explosives made with ammonium nitrate(Ammonium Nitrate Fuel Oil), however ammonium nitrate is by itself rather energetic and will explode when store improperly. The most recent memorable incident would be 2020 Beirut: https://en.wikipedia.org/wiki/2020_Beirut_explosion
Imagine one of these units left somewhere, slowly filling a tank that has not been sealed, water evaporating back out leaving a nice ammonium nitrate powder behind....
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NGL, it would be an easy sell. You are just a hop/skip and a quack away from turning that decentralized fertilizer into a decentralized bomb making system.
A hop, skip, quack, jump, and fairly obvious high-energy distillation process away. The national security angle probably isn't a concern here for the same reason that this process doesn't produce good fuel.
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What happens when your decentralized fertilizer mixes with someone's copyrighted/trademarked fertilizer? Do you have to pay them their dues?
If you think this is outlandish, you must not be familiar with Monsanto
That is an exaggeration. The only time Monsanto did anything was cases of intentional mixing.
> you must not be familiar with Monsanto
It has been out of business for almost seven years now. Who is putting any energy into remembering them at this point?
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I mean, the extended headline suggests it is producing fuel, which is wrong.
Ammonia has a lot of uses, and fuel is one of them.
It's a recent use. I'm still not convinced it's a good use case. I think it's mostly greenwashig (bluewashing?) to avoid the explicit release of CO2, but probably biodiesel is a more ecological friendly alternative.
Would it be suitable for Mars atmosphere?