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

cen.acs.org

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

#61
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This is the well known Haber-Bosch process, "Between 75 and 90% of this ammonia goes toward making fertilizer, and about 50% of the world’s food production relies on ammonia fertilizer." For those not looking to create a free account to login and view it: https://webcache.googleusercontent.com/search?q=cache:-5f9t9...

This process is the reason Malthus was proven wrong back in the day. We wouldn't be able to support 8 billion people without it.

Malthus was wrong because he assumed that people would always want to have a lot of kids.

Back in his days people would have a lot of kids because they kept dying, but he didn't realize that. Nobody did at the time.

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

#62
post #16

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…

While nuclear has different pollution than fossil fuels, one can hardly call it green with the everlasting poison it produces.

As far as I know - but please correct me if I'm wrong - the amount of waste is small enough that this is irrelevant. Additionally, having radioactive isotopes around is the natural state of affairs; after all, that's the input too.

Is the scale of the nuclear pollution really different from the scale of infrastructure-construction pollution for e.g. solar or wind? Because AFAIK either option is much, much cleaner than fossil fuel.

Finally, part of this teeth-gnashing seems to be centered on old fears. For instance, we have international treaties banning nuclear waste dumping in the ocean, but that's kind of absurd, considering that the amount is so low, and the ocean is so much larger than land, that water is quite good at absorbing and diluting residual radiation, and that any specific spot on the oceanic plate appears to be some of the least valuable ecosystem habitat on the planet. Why not just dump it in small containers somewhere in the middle of nowhere?

I believe valid concerns surrounding nuclear are primarily those of cost and delay. But this isn't some competition with e.g. wind and solar; it's a potential addition to replace e.g. coal, which is still a major power source all over the world. Comparing nuclear to solar is a distraction - if we manage to replace nuclear with e.g. solar+storage many decades down the line, that's great - but decarbonizing is extremely urgent, and we should therefore not be shutting down any routes to do so without extremely solid reasons.

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

#63
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Earlier quoted context omitted.

Quality of life. We don’t want to live like we did in the 1700s — 95% of “rich” nations back then were subsistence farmers, and even the richest kings were in many ways worse off than minimum wage G7 citizens today. This is also why I think the solution is to focus on the CO2 itself and not on the people. Green power, green sources for chemical feedstocks, are much faster and less violent than population limits; and…

I don't understand. How would two more orders of magnitude reduction make things better? We don't want to go back to the 1700s, so going back to the dawn of history is better? What would North Korea be able to produce without 2/3rds of its population and without China?

He means, CO2 as a problem requires us to reduce our additions to the atmosphere by roughly 100%.

This is entirely possible, mostly by no longer burning fossil fuels, which is the prime contributer to the problem.

It is not practical or possible via population growth reduction, which has basically already happened (people live longer so there's a delay in the result being seen, but we've basically peaked already).

Unfortunately, it's politically tricky to stop burning fossil fuels, because people with financial interests in fossil fuels would prefer to destroy human civilization instead. And one of the many ways they do that is by encouraging people to believe that modern life is impossible without burning fossil fuels and so we should kill billions of poor people instead of just using cheap renewable power.

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

#64
post #52

Earlier quoted context omitted.

Why is it damning that 88% of ammonia is used in fertilizer? Is their some other industry that ought to consume a larger percentage?

We could avoid this number by investing in soil preservation, nitrogen fixing plants, reduce meat consumption, even in concepts like humanure.

None of these would produce as much food per area and time. Reducing total calories required by eating less meat is a different argument.

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

#65
post #21
post #14

Earlier quoted context omitted.

It's possible to reduce population by about 40% in 30 years without killing anyone, isn't it? Why is that obviously insignificant?

No that is not possible without killing anyone because people will fight for the right to reproduce. You can't stop babymaking completely without violence.

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

#66
post #17

Earlier quoted context omitted.

> Replacing the hydrogen source at similar scales with electrolysis is plausible with base load power generation. There is no need to tie this to base load power generation. In fact, quite the opposite: A lot of the electrolysis projects and the funding happening right now is targetted at using electrolysis as a compensation for fluctuating renewables. This makes sense: We have cheap, green electricity, however havin…

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".

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

#67

Why is depopulation not even a consideration as a solution for climate change? Surely there are ethical ways to implement it. Or do the world's largest and wealthiest nations only care for their hold on economic power?

The problem is that there usually follows the question of who should have less children. And often the poor are seen as the problem, even though it's us rich people that emit more than we should. Famous people that are saying that the population is too high are Bill Gates or Paul Watson of Sea Shepherd, which both have 3 children.

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

#68
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post #22

Earlier quoted context omitted.

Surely the hydrogen could be stored to allow for intermittent power supply? Make hydrogen when power is cheaper and there is spare. Also, the continuous supply of power is exactly what the grid is designed to do. Availability of cheap nuclear or geothermal could change the economics. But the power is exactly the same if it comes from nuclear, renewables or battery storage.

With very-high-temperature reactors (one of potential paths for Generation IV reactors) you can produce hydrogen using reactor heat directly, bypassing the electricity conversion step, thus significantly improving efficiency of the process. And with sufficiently cheap hydrogen you would not be able to produce fertilizers, but also steel, another dominant CO2 source.

Is then hydrogen liquefied? I remember reading somewhere that hydrogen requires pretty heavy/thick containers for storage. Does it need to be kept at low temperatures?

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

#69
post #68
post #49

Earlier quoted context omitted.

With very-high-temperature reactors (one of potential paths for Generation IV reactors) you can produce hydrogen using reactor heat directly, bypassing the electricity conversion step, thus significantly improving efficiency of the process. And with sufficiently cheap hydrogen you would not be able to produce fertilizers, but also steel, another dominant CO2 source.

Is then hydrogen liquefied? I remember reading somewhere that hydrogen requires pretty heavy/thick containers for storage. Does it need to be kept at low temperatures?

The Haber-Bosch process used in ammonia production is done at high temperatures (400-500 °C), so you can use "hot" hydrogen to power it (i.e. to heat input nitrogen) and maybe even extract some of leftover energy in produced ammonia heat to generate electricity. Same with steel production, you don't need to cool hydrogen before using it, on the contrary, high temperatures are useful in such cases.

Using "hot" hydrogen would mean that you have to build ammonia and steel plants right near nuclear reactors, which can be somewhat difficult, but potential efficiency benefits could be big enough to offset it.

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

#70
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Earlier quoted context omitted.

While nuclear has different pollution than fossil fuels, one can hardly call it green with the everlasting poison it produces.

At least the poison is very concentrated and easy to store. CO2 in the atmosphere is "forever" too, and much harder to deal with.

Not really, the most abundant life forms on earth consume CO2 to grow. Of course not at the rate we would like (especially with current coverage and that we’re still freeing more carbon daily by chopping down more forests).
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