Will Japan run on ammonia? Major chemical firms want to build the infrastructure | Hacker News Reader

Will Japan run on ammonia? Major chemical firms want to build the infrastructure

cen.acs.org

77 pointsTrouble_00776 comments

This article seems rather confused at best. Take this:

> "So-called clean ammonia comes in two main varieties: green, produced with hydrogen that is created by splitting water with renewable electricity; and blue, made with traditional hydrogen from which the by-product CO2 is captured and stored underground."

Underground storage of carbon dioxide from fossil fuel combustion has been over-hyped for decades and never convincingly demonstrated. It still appears that the energy cost of collecting, piping and injecting all the CO2 from a fossil fuel combustion or hydrogen reformation process exceeds the total amoung of energy that the process generates. That means all the power produced by the fossil fuel power plant would be devoted to capturing, transporting and injecting the resulting carbon dioxide - a futile cycle leaving no energy available for any other use.

Additionally, you have to ensure that the combustion of ammonia generates N2, not NOx (nasty air pollutants). The article doesn't seem to mention it, but it is an issue, for example:

https://nh3fuelassociation.org/2017/10/01/methods-for-low-no...

I think the real meat of the article is further down, where they discuss replacing the Haber-Bosch process. That's what the article really ought to be about. Haber-Bosch is a huge emitter of CO2, and our industrial agriculture depends on it. That they intend to replace methane with ammonia would be nice, but regardless of that, if this Tsubame process can be made to work, it will have applications beyond that.

They also talk about ammonia replacing methane in power plants, which is problematic.

It’s very difficult to combust ammonia without producing a lot of NOx. That means more smog, acid rain, asthma and other respiratory disorders.

We’ve gone to huge efforts to reduce and eliminate NOx emissions from vehicles and power plants, so it would be a major setback to start adding new sources of it.

Wouldn’t industrial processes that use H2 directly generally be preferable to having ammonia as an intermediary?

NOx are industrially useful and profitable to scrub out at large scale (and relatively easy too, just pass exhaust gasses through water) because it generates nitric acid, which is an extremely useful and relatively expensive chemical that is the basis for vast amounts of industrial processes. So the use of ammonia in power plants is relatively unproblematic, in fact I would not be surprised if tuning ammonia based power plants to produce the most amount of NOx possible was the most economic choice.

As a bonus, nitric acid can be directly used to create fertilizers, which is one of the central usages of the Haber–Bosch process.

Not sure, whether there's a technically proven ammonia fuel cell yet. For some applications it could enable the use ammonia to generate electricity _without_ NOx emissions.

There is. It is practical to operate at a scale as small as a single wind turbine, for local fuel and fertilizer on a farm.

Where and how do you recommend learning more about this? Thanks.

You minimize NOx production just by running a little bit rich.

NOx output from natural gas plants is today kept down by injecting ammonia.

Haber-Bosch itself does not emit CO2. I presume you mean that the generation of H2 needed for Haber-Bosch is what emits the CO2 - unless using green hydrogen?

I worked on the Front End Engineering Design for a blue hydrogen power station with carbon capture, and I can assure you it generated net electricity export after subtracting the power and heat requirements for the CO2 compression and amine units respectively. So the phrase "It still appears that the energy cost of collecting, piping and injecting all the CO2 from a fossil fuel combustion or hydrogen reformation process exceeds the total amoung of energy that the process generates" is definitely not true. And contrary to common opinion, there is no "unproven technology" in CO2 capture and storage, every unit operation has been around for decades.

However your other phrase was 100% correct I think: "Underground storage of carbon dioxide from fossil fuel combustion has been over-hyped for decades and never convincingly demonstrated." I'm not 100% sure why that is, but I think it is probably to do with the lack of economic incentive combined with relatively little industry experience. If every Operator knew without a shadow of a doubt their Scope 3 emissions would get taxed at $100US per tonne CO2 then a whole industry would spring up and CO2 capture would become commonplace. But you don't get there with a smattering of plants across the world, with various incentives.

A few years ago I tried to dive into the question of whether DOE-financed projects like FutureGen and other fossil-carbon-capture-and-sequestration efforts had any solid scientific basis, and I always ran up a against a brick wall of proprietary data in these 'public-private partnerships', when it came to figuring out the ratio of carbon going into the plant in the form of gas/oil/coal, and carbon coming out of the plant in the form of CO2, and the fraction of that CO2 that was actually being stored vs. the fraction being emitted to the atmosphere.

My conclusion such as it was (not having full data access) was that all these plants only captured a relatively small fraction of their CO2 emissions, and more often than not, were simply using that CO2 in enhanced oilfield recovery operations - and here again, it seemed that a good fraction of the injected CO2 was coming back out of the ground with the oil it was intended to extract, then being boiled off [to the atmosphere] in the distillation process.

All in all I think it's probable that a complete external investigation of this ~20 year saga of public-private 'carbon capture and sequestration' programs at the US DOE would not look good at all, and might reveal a fair amount of blatant fraud.

[one can sort of grasp the problem by imagining if a gasoline-powered vehicle driving down the road would ever be capable of capturing its CO2 emissions in some onboard storage tank, which could then be offloaded at a gas station when refueling for 'permanent underground storage'.]

On your project, what ratio of generated energy was spent on CO2 capture and storage?

The greenhouse gas emissions of blue hydrogen production exceed those of simply burning natural gas.

https://onlinelibrary.wiley.com/doi/full/10.1002/ese3.956

Most diesel and natural gas reciprocating engines can be switched to ammonia with only changes to fuel pumps and injectors.

It's a great easily transported bridge fuel that can replace LNG export until the anti-nukes pull their heads out of their arses.

The only downside is that you're dealing with ammonia...

I'm dubious simply because ammonia is so nasty to human life. Spills are far worse than diesel or even gasoline spills.

You misspelled "replacement of the nearly the entire fuel system."

"Easily transported"? Are you nuts? It has far less chemical compatibility than LNG and is wildly more dangerous to people. It gets even worse if the ammonia has any impurities.

Ammonia is highly corrosive to zinc, brass, and copper. Copper, for example, is often used as crush washers in high pressure banjo bolt fittings used in oil and fuel lines in automotive applications.

It's wildly incompatible with several elastomers (ie fuel lines and seals) and plastics (fuel tanks, sensors, tubing, etc.)

If there are impurities in the ammonia, it starts eating the shit out of steel, too.

I doubt existing emissions control equipment would work.

Then there's the small problem of what happens when any unburned ammonia makes it past the rings into the crankcase....so the entire evap system now has to have ammonia-compatible parts...and since the evap system vents into the intake system, which is often made with lots of plastic, now you've got to replace the intake manifold. And since the oil is going to get contaminated with ammonia, the entire oil system has to have ammonia-compatible parts, too.

In modern direct injection vehicles (diesel or gasoline) you're likely at a huge number of components that would likely need to see ammonia-compatible equivalents developed, manufactured, tested, and then installed on the vehicle. The high pressure pump on most passenger vehicles is driven off a cam and tightly integrated into the engine, for example. It's not just a matter of "swap out the fuel pump." Fuel tanks in passenger vehicles are often plastic and not trivial to remove, at all.

Oh, and: renewable energy sources are significantly cheaper than nuclear, which is why wind and solar are replacing decommissioned nukes at a ratio of 6:1.

You seem a bit outside your lane.

Really interesting. Could you post some sources?

>"Easily transported"? Are you nuts? It has far less chemical compatibility than LNG and is wildly more dangerous to people. It gets even worse if the ammonia has any impurities.

Why would there be impurities in ammonia generated from solar powered water electrolysis? Where are they coming from?

Why would clean NH3 react strongly with carbon-managanese steel pressure vessel used in LNG transport?

>I doubt existing emissions control equipment would work.

Is emissions control installed on large marine diesels and stationary generation in Japan?

>In modern direct injection vehicles

Bzzzt. Wrong. This article is about coal power.

Water is such an impurity. Even diesel system can have problem with water condensing out of air during day/night cycle if no precautions are taken. And diesel won't react with water but ammonia will and very eagerly.

I doubt anybody seriously thinks ammonia will be a fuel in cars.

But is practical for ships and peaker plants.

Yeah, ammonia and hydrogen as ways to store energy have significant challenges, they probably aren't worse than if we had to store natural gas. Ammonia is corrosive and needs to be cold, hydrogen needs to be compressed to be energy dense so it needs heavy walls. Both explode. Hydrogen leaks a lot around seals and through them, but welded tanks probably do fine.

Natural gas needs to be compressed to be energy dense as a liquid, it explodes, it maybe has some technical advantages but the benefits seem narrow if you're starting from a fresh analysis. We're good enough at it to switch to an ammonia economy, people handle it safely all the time. It's just different risks.

Natural gas is fairly safe (non-explosive) while compressed. It has to decompress and reach a pretty specific ratio of air-methane mix before it becomes explosive.

Hydrogen, by comparison, is explosive across a much wider range of pressures and concentrations.

Hydrogen also needs to be stored at far higher pressures than natural gas in order to reach comparable energy density, which makes it more difficult and expensive to handle and transport.

We will not be using compressed hydrogen, so that doesn't matter. LH2 is kept at atmospheric pressure.

Liquid hydrogen is also pretty difficult and costly to store and transport, because it requires cryogenic storage. You need to make sure to keep it at −252.87 deg C or it's not going to stay liquid for long! It also takes a lot of energy to compress into a liquid in the first place, making it much less efficient as an energy carrier.

Hydrogen used to get used a lot by the space industry (Space Shuttle, etc), but now days the modern rocket industry has been moving to other fuels (kerosene, methane) - largely because of the greatly reduced costs of handling those fuels!

We are already quite well practiced in handling and transporting liquified methane, which in only incrementally easier than LH2.

Rockets are lately designed for methane in large part so that concentrating Martian atmosphere for fuel will be more practical, but also for CO2's greater molecular mass, important in an earthly first stage launcher, which needs absolute thrust, to get moving in 1G, much more than efficiency.

As fuel, LH2 may find use mainly or even exclusively for aircraft, but it is exceedingly valuable as feedstock for other work, including ammonia and, yes, methane synthesis. Methane is itself feedstock for many other processes. Ideally these would not result in released CO2...

Hydrogen will not be compressed, but rather liquified.

Hydrogen is prevented from exploding by assuming all joints leak, and providing continuous positive airflow to keep concentration always below 5%.

Methanol is probably better than ammonia as a vector for green hydrogen. It carries less hydrogen per volume, but it's a liquid at room temperature, trivial to transport, and it's generally less dangerous. It's also been used as a fuel for reciprocating engines for more than a century.

Methanol and ethanol share the same fundamental problem: they are both carbon-based, and despite global warming atmospheric CO2 is still well below 0.05% of the atmosphere which means it is very resource-consuming to extract it. As long as we still use some fossil fuels, you can capture at power plants, but in the long run it is a dead end.

Ammonia, on the other hand, just requires nitrogen which is 70% of the atmosphere and very easy to extract in industrial quantities.

You don't need to extract CO2 from the atmosphere using direct air capture (I agree that it's a dead end); you use existing sources of waste to intercept the carbon cycle. Sewerage, for example, contains carbon that was pulled from the atmosphere by a plant, or bacteria in the soil. Ditto for municipal solid waste, especially wood products and paper. If you need additional sources, you can grow fast-growing plants (seaweed is preferable, since it doesn't rely on good land) to pull carbon out.

When you make methanol, processes like gasification and pyrolysis leave you with excess carbon in the form of carbon black, or ash. If you sequester this before it oxidizes, fuel production becomes carbon negative. Methanol is better than ethanol because a) you can't drink it, b) the single carbon molecule means it burns cleaner, c) you get more fuel for the same initial amount of carbon, and d) it doesn't compete with food production for arable land.

And the emission control system.

At least from the leading paragraphs, it sounds more like "switch from CH4 to NH3 for industrial-scale uses". Vs. actually using NH3 for residential heating and such.

Wikipedia says ammonia is lethal above 500ppm...so probably not something that savvy residential users would be eager to switch to.

And - if any little glitches in your distribution system let water in, you'll soon have concentrated NH40H in there...dangerous, very corrosive, and likely to do further damage.

Yes there won't be any ammonia use in domestic heating. Ammonia travels well by shipping because you can easily refrigerate it to a liquid, but I doubt it's going to become a widely-distributed fuel.

It is also liquid at normal temperatures given minimal compression. It will be practical to replace bunker oil on ships just by replacing tankage and plumbing, and maybe on trains.

As toxic as it is, if leaked it goes up fast, so would not blanket a surrounding area like, e.g. methyl isocyanate (cf.). That said, spilling a lot of liquified NH3 could be bad.

There's no way people are going to be burning ammonia in personal engines. The pollutants from burning it are far worse than burning hydrocarbons. On industrial scales it might be feasible to scrub the exhaust (and even recycle them, since they're economically valuable) but on small scales I doubt it could be done.

Can anyone please enlighten me on: Why isn't more being done to build out infrastructure related to Green Hydrogen?

It seems it just needs Water + Solar Energy.

One would think it would be the top priority worldwide.

Because liquified hydrogen requires more containment than gasoline and you need really clean water to make reasonable hydrogen.

AFAIK Nuclear is a lot better for this than PV anyways.

I'm in the "PV is greenwashing" camp, I worked for Solyndra, that stuff was d i r t y.

What did you do at Solyndra? I didn’t notice it listed on the resumé in your profile.

I was a subcontractor for a larger company.

Why are you generalizing relatively uncommon thin film solar panels to all solar panel types? I swear this is extremely common. People just say look these panels are bad, and nobody mentions that they are like 10% of the market at best.

Because they literally are all that bad.

It's not a very good form of energy storage or transport. It's not dense either as a gas or as a liquid, so it'd be difficult to use in all the places gasoline, propane, etc. are used now. It also burns very hot in a combustion engine and causes nitrogen dioxide pollution in the process. It's a solution, sure, but not a great one.

I suspect it's inertia, and it's gradually disappearing.

Where I live proposals for projects like these are becoming almost common now:

https://infrastructurepipeline.org/project/central-queenslan...

https://www.industry.gov.au/data-and-publications/exporting-...

But go back 5 years or even 2 years, and the only exported energy projects bring proposed were gas fracking and coal mines. My, how times have changed.

The top priority is building enough renewables that storage begins to make sense. We're pretty far away from the point where it's cheaper to store energy as hydrogen than, for example, to make the demand side more responsive to changing supply. Until you literally don't know what to do with the oversupply you sometimes get from wind and solar, it makes little sense to throw a large part of it away to produce hydrogen.

Storage isn't the only reason to invest in green H2. It is e.g. the most plausible path for decarbonization of many industry sectors, including steel and chemicals. And these are often technologies that are in early stages.

I don't think this "first you need to do X, only then can you do Y" approach fits for the current situation. These technologies need to be developed now.

Developed now, yes, but built out later. Money is much better spent now on top-line renewable generating capacity.

Of course there are pilot electrolyzers, mostly for R&D. There are a couple MW worth in Germany for example. But there is no point in deploying them at scale until in makes economic sense. Until policy makes GHG emissions sufficiently expensive, nobody buys green hydrogen if natural gas is available.

Blue hydrogen is cheaper. No one would buy green hydrogen.

Often said, but questionable if you want to have strict emission standards. The existing "blue h2" projects are abysmally bad, they only capture a small fraction of the emissions produced (see e.g. [1]). That you can run cheap blue H2 with low emissions - both upstream methane and CO2 that isn't captured, because CCS is never 100% - remains to be shown.

[1] https://www.energymonitor.ai/tech/hydrogen/shells-quest-blue...

Unfortunately very few potential buyers of hydrogen want to have strict emission standards right now.

It's simply because it makes a poor energy carrier.

You can also make methane from Water + Air + Solar Energy, and methane is a lot easier to deal with.

That needs a source of carbon.

That's what the air is for, you pull the CO2 right out of the air and use it for carbon.

CO2 is under 0.5%. Concentrating it is energetically expensive, although as energy cost continues down, cracking it may yet prove cheaper than mining and transporting CH4. Still, having concentrated CO2, it would be much better to fix it in a form from which it would not immediately be emitted back to the atmosphere, such as graphene, graphite fiber, nanotubes, or a polyester or polypropylene.

Most uses also need hydrogen. There will be a great deal of waste oxygen. That might best be dissolved into river water.

... under 0.05%, that is.

Electrolysis is very inefficient and other production methods are hydrocarbon-based which means you're just playing games with where the carbon is being released.

Hydrogen molecules are so small, it leaks out of everything, and leaks through a lot of things.

It embrittles a lot of metals.

It causes MEMS electronics to stop working.

Thanks. I thought you gave the most apt reasons.

Conventional alkaline electrolysis is about 70% efficient and PEM electrolysis about 80% efficient. That's pretty good. The round trip to electricity is of course worse, but hydrogen itself has many industrial uses.

In Europe a lot is happening, some companies are investing big into production capacities, see e.g.: https://blog.topsoe.com/haldor-topsoe-to-build-large-scale-s... https://www.westkueste100.de/en/orsted-en/ https://www.rwe.com/en/research-and-development/project-plan...

However one thing to keep in mind is that while extremely promising, green hydrogen is usually more expensive than gray hydrogen. (There have been some estimates lately with the high gas prices in Europe that this is different now, but that's of course only a very recent development.) So without policy support it's hard to make green Hydrogen happen. Unfortunately the US is still struggling to have any significant climate policy at all (thanks Joe Manchin).

Getting decent energy density requires thick walls and difficult seals at high pressure. Hydrogen leaks very easily.

Conveniently, ammonia is quite energy dense at atmospheric pressure or a bit above...

Where hydrogen is transported or used for fuel, it will be liquified and kept at atmospheric pressure; or stored underground at low pressure.

Ammonia is more practical for transport.

Some would say there is actually TOO much being done with green hydrogen.

Hydrogen is very difficult to transport and almost all of the world's 90 million tons annual consumption is generated locally.

Hydrogen is a very sexy attracting a great deal of interest and investment and unfortunately distracting away from more straightforward decarbonisation pathways like electrification, smart grids and Closed-Loop Pumped Hydro Energy storage.

Hydrogen will have practically unlimited importance as feedstock for other processes, not limited to synthetic ammonia and methane, use refining iron ore and producing steel, and as liquid fuel for aircraft.

Why don't countries go hard on nuclear instead of playing around with these "sustainable" new fuel types?

They all consume a finite resource so it's really pseudo sustainable at best.

The only real sustainable energy is sun, wind and hydro.

Ammonia is a practical storage medium, to be produced from excess solar and wind. And, it is useful as fuel for ships, which cannot competitive driven by solar or wind.

In Japans case because of Fukashima; whatever your views on Nuclear you can't really blame Japan for being spooked by that.

Coz it's absurdly expensive to begin with even if it doesnt blow up at a cost of $800 billion like it did in Japan.

Realistically it barely competes as it is with pumped storage, batteries, solar and wind even when taxpayers provide free disaster insurance and lavish subsidies.

Isn't ammonia super toxic and lethal to humans?

At the top of the article: "It is a flammable and toxic gas, and in Japan it is regulated by several safety laws."

I wouldn't say "super" toxic. Household window cleaner is 30% ammonia.

Yes. And a farmer can hitch a pickup to a trailer filled with 1500 gallons of anhydrous ammonia and take ‘er home.

Assuming it's not 100% efficient, what does ammonia emit when burned?

Nitrogen oxides for one thing.

Ah, not so great then. Although a quick trip on the goog indicated it can be burned at lower temps with less noxious output, though it may be a fine line to walk.

Also, NOx scrubbers that remove a large percentage of it from combustion gases have existed for a long time because we use them in fossil fuel plants.

That's good then-- preexisting proven technology.

Unpaywalled -> https://archive.ph/arDQf

This seems pretty cool. I'm not super familiar with the technology but from what I took out of the article it won't be a straightforward replacement for a lot of solutions. That said, seems neat, I'd be curious to try.

Reply on news.ycombinator.com