Ammonia powered engines

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Lots of chatter about ammonia in energy circles. I'm skeptical of ammonia for light vehicles (where EVs are going to be a great and cheap solution). So folks are talking about fuel for ocean going ships and other heavy vehicles.

This assumes the development of a 'green hydrogen' economy which makes it from renewable energy, versus the current natgas Haber-Bosch process. That will probably develop only after we have much more RE penetration than today, with lots of excess production to burn. Like in 5-10 years.
If it’s possible to make it work, transporting and storage of liquid ammonia wouldn’t require entirely new infrastructure like transporting and storing hydrogen gas. I imagine NOx could get pretty high burning ammonia.
I have had several run ins with Ammonia over the years, none of them good. My first battle was a DIazo blueprint machine that used aqueous ammonia. It was in small poorly ventilated room and when we had to switch the bottles out we usually got lots of complaints. My next Diazo machine was a production machine that used compressed ammonia. We had a leak one day and the Hazmat team showed up. After a couple of hours we were allowed back in the building and within a few days we had to permanently abandon the unit and go with a Xerox type printer.

The next encounter was with the EPA over a bulk liquid ammonia tank. We used a lot of it for PH control and it came in by rail. The railroad really hated carrying it and the bulk system always had minor issues. At some point Liquid Ammonia became one of the EPA highly hazardous chemicals that had to be covered under Hazcom regulations. One of the many requirements of the regulation is we had to have a map made projecting the zone of danger around the bulk tank that went out a couple of miles or so. Any public building, medical facility or nursing home had to be identified on the map and evety listed facility became an unwilling partner. We had to go through a Hazop process and had to have emergency training drills on the system. We eventually switched to Aqueous Ammonia and condemned the liquid system. We switched to aqueous at a higher cost but lower paperwork and risk.

I also worked in a facility with a large liquid ammonia system used to recharge a large desiccant system used in a candy factory. The factory was on the edge of closing down and had been transferred to new owner's so a lot of experience had left the place. I warned the new owners that they had a big liability with the volume of ammonia they had in inventory and that they needed it decommissioned well. I did my thing and went away and about 4 or 5 weeks later I heard of major Hazmat incident when someone vented the system improperly.

There are specialty contractors who deal with ammonia but its nasty stuff especially anhydrous as it can expands rapidly and can cause a BLEVE . of heating from air temperature and sunlight.

The strange thing is farmers use most of it produced in the US to inject into fields to boost production.
But how does all that compare to the regulations around gasoline?
Let it evaporate in a room, train cars full of it - all potentially deadly too?

Ammonia is nasty, but gasoline too. We've learned how to deal with it. Can't we do the same with ammonia?
Gasoline is stable in a liquid form, concentrated ammonia is not, makes big difference in handling.
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Gasoline is stable in a liquid form, concentrated ammonia is not, makes big difference in handling.

A lot more like propane in terms of handling....
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We used anhydrous ammonia as fertilizer. Thanks we’re 4 wheeled 500 gallons. Regular rate was about 500 gallons per 80 acres. Heavy was 1000 gallons. I was 14 a learners permit and was told to take the the lodes bobtail to town and dump it at the elevator after one ride along. I was 21 before I was allowed to change over a tank in the field by myself. It’s nasty stuff.
A lot more like propane in terms of handling....
I think it’s about 5x more dangerous than propane. Inhaling a big breath of propane doesn’t scare me. Ammonia does.
I think it’s about 5x more dangerous than propane. Inhaling a big breath of propane doesn’t scare me. Ammonia does.
It forms a base on contact with water, including mucus membranes. Just the working pressure and tranfer methods of the liquid are similar to propane.
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The strange thing is farmers use most of it produced in the US to inject into fields to boost prod
Yes, we live in the heart of rural farm America. Anhydrous ammonia is used a lot for fertilizer. It’s not used as much as it was in years gone by, but there are still large storage facilities all over the place. It is highly hygroscopic. You wouldn’t think there is much moisture in a dollar bill, but if you drop one into anhydrous ammonia, it will shrink to less than half size because it draws the water out. It would also do that to your body, especially the lungs. You don’t have to breath many breaths and you are finished. I’m on a couple of volunteer fire departments, so we have done training on it periodically. It’s amazing that we don’t have too many incidents with it. Farmers in general, though, are quite level headed and take the necessary precautions. I’m not sure how the general population would be. The biggest problem in years gone by was that people used it as an ingredient to make meth, so they would sneak into these storage facilities or a tank that was in the field and bleed some off for their nefarious purpose. They must have moved on to different stuff, though, because that doesn’t happen anymore. Once we were called out after the county sheriff deputies had a storage place staked out and someone came there and stole some. They chased them, and while they were chasing them, these people were bleeding some out of their tank out their window so the cops couldn’t stay close behind them. The police had to trade off so they wouldn’t be overcome by the fumes. The deputies prevailed, though, and a couple of flat tires later and a cow being hit, they were arrested.
Blueprint and Diazo units , yep repaired those back in the 70"s. Had a 8ft wide print unit blow a liquid ammonia line, Full hazard suit with oxy tank 3rd floor up. What a fun several days for me( not) . Building totally vacated and several blocks around also blocked off . Naturaly it was about the highest temp week of the summer. Had to purge all the lines from the big outside stoage tank and pressure test everything to find the leak all while bumbling around in that suit.
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