Putting the life back in science fiction

Facepalm with a hit of nitrous
July 28, 2016, 7:01 pm
Filed under: climate change, futurism, Real Science Content, Uncategorized | Tags: , ,

I’ve been advocating for a partial switch to an ammonia-based economy, on the theory that, while NOx is an air pollutant, it’s better than CO2.

Facepalm time: N2O, good ol’ nitrous oxide, which is another thing that comes out of of using ammonia for fertilizer or burning it, is a greenhouse gas 100 times more potent per pound than CO2.  Right now, it’s 5.9% of US greenhouse gas emissions.  It supposedly lasts about 114 years in the atmosphere, until it gets broken down by some process or other (I’m being lazy about all the bits and bobs in the nitrogen cycle, because it’s hot here, and with a flex alert on, I’m not running the AC). Unlike CO2, it doesn’t look like it sequentially saturates large sinks and stays around for hundreds of thousands of years in the atmosphere.  Rather, it just breaks down slowly.  About 40% of the N2O emitted in the world is from human activities, and it can be cut, in some circumstances, through catalytic conversion technology.

Here’s some really basic information on it (link to EPA)

The basic sources for atmospheric N2O are:

  • conversion of nitrogen fertilizers to N2O by bacteria.  This is the big one, and more efficient fertilizer use and better land management can cut this to some degree.
  • it’s a combustion byproduct, so it comes out the tailpipes of gas-burning cars.  Catalytic convertors can help with this.
  • various industrial processes produce N2O as a byproduct.

Now, the simplistic solution is hydrogen, except that (IIRC) burning hydrogen using air also may release some N2O, because there’s a lot of nitrogen in the air.  Converting to fuel cell-type devices that do electrochemistry rather than combustion and using catalytic convertors on combustion-powered systems probably is the way to go.

It does get more complicated than that.  While catalysis is the simple-minded solution, it’s also prey to the usual simple-minded problems with polluters who don’t keep that part of their car (or other system) working, and thieves after the platinum in the convertors.  It’s the usual, intractable problem: environmental problems, greed, and stupidity don’t mix.

So, what do you think?  Pitch any desire for an ammonia economy out the window and pray for hydrogen and better batteries?  Double-down on catalysis, which catches NOx better than CO2, and start prospecting for platinum at the side of the local highways?  Stick with fossil fuels and assume we’re all doomed?  Some combination of all three?

Oh well, tonight I get to watch  the latest episode of the newest superhero series: Suit Woman vs. Generalissimo Cantaloupe.   I’m not sure binge watching is the right word for it (more the opposite), but it does seem to be the thing everyone’s talking about this season.


11 Comments so far
Leave a comment

So, I found a mouldering copy of the original The Limits to Growth in a moldy shop a few weeks ago. Since the 30-year update showed its forecasts have been rather surprisingly accurate, given the “spherical cowness” of its model, I’ve been ruminating on the following proposition:

Unless we can achieve an entirely steady-state economy, with mandatory consumption and birthrate controls all around — which would imply a pretty much Bolshevik-Revolutionary-level remaking of our society — any technical fixes will make our predicament worse, not better.

Because the Club of Rome simulation predicts that, to the extent we make resources go further using technical innovations, and don’t use political/ideological means to reduce population and energy consumption — these technical fixes merely make industrial civilization burn brighter, for a little longer, and crash harder. Ultimately, more greenhouse gas will be created this way (from the stuff that requires the high tech to get at, like shale oil and fracked natural gas) — not to mention other pollutions, like plastic everywhere — and the “hangover” from our civilization will be that much worse.

So a partial “fix” is worse than no fix at all. This is one of those cussedness-of-complex-systems things.

I think we can take it as read, at this point in time, that no full transition to a steady-state economy is possible given current structures of Power.

In descending order of preference, then:

(1) At the personal and family level, go full Amish — don’t try to keep your life as you know it running at all. (Is this effectively impossible for the average wageslave? Yes.)
(2) Stick with fossil fuels and we’re all doomed.
(3) Add technical and “green” fixes to the fossil fuel mix, and the biosphere is screwed worse than under (2), although civilization will get a few extra decades of miserable partying in.

Comment by a scruffian

Good for you, I’ve only seen the graphs, not the whole report.

That said, there’s a really dangerous assumption in there, about steady state or bust. That’s sort of general ecology 101, with the assumption that there exists a thing called carrying capacity.

There are a couple of ways to look at it. One is to look at how plants grow. Even when they’re at “steady state” in terms of mass, parts of them are dying and parts are growing. Civilization works the same way. It’s kind of clunky and always falling apart. The very idea that it can exist in steady state is silly, any more than a car can exist in a steady state. Civilization is very metastable at best, it exists far from equilibrium (steady state is, by definition, an argument of equilibrium), and without constant change, repair, and inputs, it falls apart. As (incidentally) does every living system.

And that’s a kind of solution: steady state sustainability is impossible. We’re never going to have control of the changing climate, human reproduction, resource issues, or the impact of random disasters. The closest we can get to steady state is when things are falling apart in rough proportion to how they’re growing/healing/rebuilding elsewhere. In other words, in the next century, we will see parts of the planet falling apart (cf: Syria), while hopefully other parts of the planet transform themselves massively towards sustainability and even make it–for awhile. They will inevitably run into trouble. Civilization can persist as long as the places that are growing into sustainability can help the places falling apart become sustainable before they hit their own crises and need rescuing to become sustainable again. It’s a very chaotic form of metastability, but it might work. You’re quite right that it will work better with fewer people, but getting to zero net global population growth is a crisis in itself, since basically it means that a lot more people need to be dying unexpectedly at some point in the next few decades.

Comment by Heteromeles

I think “steady state” in the Club of Rome model indeed translates to the “clunky” metastability or homeostasis of the stochastic and noisy real world you describe. It’s not a dead inorganic equilibrium of course. It just means the annual difference between births and deaths is sufficiently small on average, while at the same time “wealth” (industrial output per capita) is not so low that we consider the situation intolerable, failed, or collapsed.

Taking a step back, though, I agree that artificially imposed metastability is a chimera, since, speaking Darwinianly, involuntary birth control is little better than murder. Most people would always resist it. To the extent that metastability is achieved in the future, it will be by the same means as always; namely the Four Horsemen.

Comment by a scruffian

Hmm. If you’re going by the original “Club of Rome” model, I suspect that no, they really meant steady-state. Metastability wasn’t really in the lexicon or the toolbox when they did their initial model.

The problem with a metastable system is that breakdown is a lot less predictable than it is if you assume there’s a constant carrying capacity. It’s not a matter of overshoot and die in a predictable fashion, it’s more a matter of losing critical resources or connections at the wrong time.

Note that, with metastability, I’m handwaving. It seems to fit the patterns we see, but turning it into a numeric model and figuring out if it has predictable failure modes requires somebody who’s a hell of a lot better with math and model-making than I am. Right now, my best guess is that things will keep working until we hit too many problems we can’t properly fix. The problem is that “too many” and “can’t properly fix” are *very* difficult to define.

Comment by Heteromeles

If surface water from urban roads/highways is conveyed through municipal sewers to water treatment systems, wouldn’t existing water treatment facilities have the best chance at sieving for platinum, Alternatively, water treatment plants could just allow the platinum to sink to the bottom of the tank same as removing gold particles from crushed ore. (Looks like this could be done as per SMURRF … Santa Monica, CA.)


Good way to defray operating costs too.

Comment by SFreader

Maybe, but only if the systems flush themselves clean. My impression is that some do, some dump stuff in detention basins to keep from clogging downstream structures. There’s probably a bunch of mining claims waiting to happen there. Or clever contractors will make money by filtering the junk they clean out of detention basins before they take it to the landfill. Or something.

Comment by Heteromeles

I’m not a huge fan of hydrogen. Superficially it seems like it could use much of the natural gas infrastructure, but it seems to have failed to catch on despite initial high hopes. In contrast, battery technology is making headway on both technology and costs. Musk is predicting $100/KWh by 2020, which will make home solar storage and time-shifting sensible, as well as making electric cars much more competitive. It isn’t a complete solution, but it will help considerably. Change farming methods to reduce excessive nitrogen inputs and another leg is installed to reduce N2O emissions (as well as nitrate runoff and toxic NOX emissions. The more we make the world go electric, the easier it is to control emissions at source from any combustion processes.

Comment by Alexander Tolley

I searched Google Scholar with terms

“engine” “exhaust” “nitrous oxide” “ppm”

I found, surprisingly, that N2O emissions from hydrocarbon fueled vehicles appear to mainly be side products of catalytic systems that are designed to reduce other emissions; e.g. http://www.tandfonline.com/doi/pdf/10.1080/10473289.1992.10466971 and http://www.inderscienceonline.com/doi/abs/10.1504/IJPT.2014.059410

I also found this great 2011 PhD thesis about ammonia combustion and its minor products: http://dial.uclouvain.be/downloader/downloader.php?pid=boreal:89103&datastream=PDF_01

See chapters 8-10 in particular. Short version: N2O formation during ammonia combustion is suppressed by increasing pressure. In an actual internal combustion engine, the amount of N2O in the exhaust is below analytical detection limits whereas it was readily detected as a byproduct from low pressure open flames.

The final twist is that the exhaust measurements in chapter 10 show that ammonia engine exhaust would need some sort of post-treatment too to avoid polluting the atmosphere with residual NH3 and NO. That could end up forming N2O just like hydrocarbon-vehicle catalytic converters do. But it would take an extraordinarily bad converter design to make the global warming impact of renewable-ammonia engines worse than equivalent fossil-hydrocarbon engines.

Comment by Matt

Thanks for the analysis Matt. I’m not sure why you and Alex keep getting hung up in the approval queue, but I’ll keep approving them as fast as I see them.

Comment by Heteromeles

I don’t see my last comment. I suppose it may be awaiting approval due to the multiple links it contained.

I wanted to add: even if you want to end up using hydrogen in an engine or fuel cell, ammonia can still be useful as a hydrogen carrier. If you keep hydrogen as H2 and contain it physically, e.g. cryogenic liquid tanks or extremely high pressure gas tanks, you spend energy on liquefaction or compression and need complicated storage vessels. If you store hydrogen as ammonia and then decompose it again to nitrogen and hydrogen near the point of use (e.g. http://phys.org/news/2014-06-hydrogen-breakthrough-game-changer-future-car.html ) then you spend energy on molecular transformations to and from ammonia but can use simple storage vessels that achieve higher specific energy.

Comment by Matt

Good point. Convert the ammonia to hydrogen at the point of use. Burning H2 can be made to produce very little NOX. If ammonia handling can be made foolproof and very safe, it might even make sense for domestic use. An issue will be how to handle the inevitable spillage accidents from storage tanks and pipelines.

Comment by alexandertolley

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: