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Industrial ammonia emits more CO2 than other chemical-making reactions (2019)

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Re: Industrial ammonia emits more CO2 than other chemical-making reactions (2019)

#91

Post by sokoloff »

coolhand2120 wrote: post #36
jackyinger wrote: post #5

This is very interesting from an agricultural perspective. According to the Wikipedia article for ammonia, “In the US as of 2019, approximately 88% of ammonia was used as fertilizers”. To me this is a very interesting and damning fact with regards to current dominant agricultural practices. Yet another reason that it would be beneficial to further redevelop closed loop nutrient systems. For instance, sewage solids fr…

> For instance, sewage solids from cites in are sold to farmers for use as fertilizer. If this was human waste wouldn't it have to be treated to remove chemicals viruses? Couldn't you get HEP-A from this process? Seems impractical and dangerous.

Biosolid fertilizers are widely used for decades in turfgrass. That’s not a claim that they’re risk-free, but rather just noting that it’s a well-established process.

Milorganite is probably the best-known nationally available brand you can buy in the home center near you, but some municipal treatment plants also sell locally to small/home users in addition to the more commercial scale usage (golf courses, etc)

I’m not sure of their level of use in feed grasses.

Re: Industrial ammonia emits more CO2 than other chemical-making reactions (2019)

#92

Post by Retric »

hannob wrote: post #66
freemint wrote: post #42

Earlier quoted context omitted.

This works because electrolysis equipment is cheap, so shutting it down half time barely increases total cost of ownership compared to the input electricity.

Unfortunately that's not the case. Electrolyseurs are expensive (though hopes are they're gonna get cheaper quickly, as there's a lot of investment in this sector right now). The economic balance of running an electrolyseur only part of the time is something to be worked out. Still the balance is almost certainly not "we need baseload".

The cost of electricity is already vastly more import than the cost of an electrolyzer at scale. https://www.semanticscholar.org/paper/Economics-of-convertin...

It’s to the point where even running 1/3 the time at the cost of 3x the equipment is likely a cost savings at scale assuming the local grid has a lot of wind/solar.

Re: Industrial ammonia emits more CO2 than other chemical-making reactions (2019)

#93

Post by pfdietz »

fuoqi wrote: post #84
pfdietz wrote: post #76

Earlier quoted context omitted.

HB consumes energy in its compressors, but releases that energy as heat on the catalyst. Hot hydrogen doesn't compress well, so you'd cool it beforehand.

For HB you need pressure of 250-350 bars, while existing PWRs routinely work with 150 bars of coolant pressure. I assume it's possible to produce hydrogen with the necessary pressure using VHTRs, i.e. you would get hydrogen already pressurized and hot. You would still need to run compressors on input water, but it's much easier than working with hydrogen later.

Producing hydrogen at pressure doesn't eliminate the energy needed, it just forces the electrolyser to act as the compressor (the voltage goes up).

Re: Industrial ammonia emits more CO2 than other chemical-making reactions (2019)

#94

Post by ambericanonion »

Collecting cat urine for ammonia production (as was done in the past) might make more sense these days, as the food cost would be offset by the near unlimited supply of cute cat videos - which could be detected with AI. The carbon emitted by respiration would probably be dwarfed by the emissions from users watching the videos, so more work is required on the efficiency of video playback before this could become a viable solution.

Re: Industrial ammonia emits more CO2 than other chemical-making reactions (2019)

#95

Post by Retric »

ZeroGravitas wrote: post #51
freemint wrote: post #42

Earlier quoted context omitted.

This works because electrolysis equipment is cheap, so shutting it down half time barely increases total cost of ownership compared to the input electricity.

I don't think electrolysis equipment is particularly cheap, there's some excitement about cheaper alternatives coming to market and mass production that use cheaper materials. But overall it's going to be the cheapest way to make hydrogen and then ammonia very soon. And the market has already seen that inevitable future, lots of right-wing Australian mining billionaires have jumped into the market hard for example. T…

The equipment is cheap relative to the cost of electricity to run it.

This analysis is 5 years old and it was already the case back then: https://www.sciencedirect.com/topics/engineering/hydrogen-pr...

Re: Industrial ammonia emits more CO2 than other chemical-making reactions (2019)

#96

Post by pfdietz »

ZeroGravitas wrote: post #54
otherotherchris wrote: post #25

Earlier quoted context omitted.

If electrolysis can be made cheaper (E-TAC looks promising) you can run it at a reduced duty cycle on excess solar and wind power whenever they are available. You can also produce hydrogen at the point of generation if water is available, and store it using the now obsolete natural gas distribution network.

People need to flip this excess electricity idea. The cheapest power is solar and wind. If you build an ammonia plant, the cheapest way to get the power you need is to build solar and wind. You can sell some excess to other grid users when you have too much, and you can stop production on very short timescales to help balance the grid during peaks but overall you'll be able to predict energy production years in advan…

Green hydrogen becomes a source of more dispatchable excess power on the grid. This is more valuable than just randomly available power on the grid. Those renewables powering the ammonia plant can be diverted to sell to the grid when prices there are high.

Re: Industrial ammonia emits more CO2 than other chemical-making reactions (2019)

#97

Post by fuoqi »

pfdietz wrote: post #93
fuoqi wrote: post #84

Earlier quoted context omitted.

For HB you need pressure of 250-350 bars, while existing PWRs routinely work with 150 bars of coolant pressure. I assume it's possible to produce hydrogen with the necessary pressure using VHTRs, i.e. you would get hydrogen already pressurized and hot. You would still need to run compressors on input water, but it's much easier than working with hydrogen later.

Producing hydrogen at pressure doesn't eliminate the energy needed, it just forces the electrolyser to act as the compressor (the voltage goes up).

Please, read the thread carefully. The point is that with VHTRs you don't need the usual electrolysis to split water into hydrogen and oxygen. Instead you can use high temperatures produced by a reactor to power conversion directly, thus improving the process efficiency. The most common option is the sulfur–iodine cycle. Granted, it's not so suitable for producing hot pressurized hydrogen (though it may be possible to separate iodine and hydrogen without condensation), but there are other options for thermochemical water splitting like high temperature electrolysis, which requires less electricity than electrolysis under STP.

Re: Industrial ammonia emits more CO2 than other chemical-making reactions (2019)

#98

Post by pfdietz »

octoberfranklin wrote: post #30
jackyinger wrote: post #5

This is very interesting from an agricultural perspective. According to the Wikipedia article for ammonia, “In the US as of 2019, approximately 88% of ammonia was used as fertilizers”. To me this is a very interesting and damning fact with regards to current dominant agricultural practices. Yet another reason that it would be beneficial to further redevelop closed loop nutrient systems. For instance, sewage solids fr…

> For instance, sewage solids from cites in are sold to farmers for use as fertilizer. Seattle tried shipping their shit (literally) to the farmers in Central Washington. Used these trucks that had "loop: turn your dirt around" splashed on the side. Then the farmers decided maybe they ought to test that stuff for PFOA/PFAS before applying it to their most valuable asset. You don't see those trucks anymore.

A local "green" grocery went from selling hot food in plastic clamshells to using compostable cardboard. One guess what that cardboard is coated with to prevent liquids from soaking into it.

Re: Industrial ammonia emits more CO2 than other chemical-making reactions (2019)

#99

Post by pfdietz »

fuoqi wrote: post #97
pfdietz wrote: post #93

Earlier quoted context omitted.

Producing hydrogen at pressure doesn't eliminate the energy needed, it just forces the electrolyser to act as the compressor (the voltage goes up).

Please, read the thread carefully. The point is that with VHTRs you don't need the usual electrolysis to split water into hydrogen and oxygen. Instead you can use high temperatures produced by a reactor to power conversion directly, thus improving the process efficiency. The most common option is the sulfur–iodine cycle. Granted, it's not so suitable for producing hot pressurized hydrogen (though it may be possible t…

Thermochemical cycles like that have been explored for decades and have gotten nowhere. For some wonderous reason, systems that involve vaporized high temperature sulfuric acid and the like have not proved to be practical. Falling cost of electrolysers and electrical power make that approach even more of a nonstarter.

Re: Industrial ammonia emits more CO2 than other chemical-making reactions (2019)

#100

Post by the8472 »

jandrewrogers wrote: post #7

Yes, this is the case due to the enormous scale of production. Replacing the hydrogen source at similar scales with electrolysis is plausible with base load power generation. The cost increase is a small integer factor, and in the bigger scheme of things is likely something we can adapt to at least for agriculture. An obvious challenge is that we don't have available green base load power -- nuclear, hydro, or geothe…

Or, until we have enough excess electricity, we could replace methane steam reformation with pyrolysis.

https://en.wikipedia.org/wiki/Hydrogen_production#Methane_py...

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