1
$\begingroup$

When I was recently studying biomass-to-electricity (gasification methods, Drax power station...), I was wondering whether the efficiencies of these systems would not benefit from a source of pure oxygen gas: if such a gas were to be used as the oxidans, in stead of ordinary air, the reaction heat resulting from combustion would be spread out over a smaller number of molecules per reaction and thusly a higher boiler temperature could be achieved. Moreover, it seems that -at least in the Drax power station- a consideration that keeps the boiler temperature and plant efficiency down is the concern over NOx formation in the boiler room (N$_2$+O$_2\rightarrow $NOx), some of which can be removed using catalysts in the chimney, but not all of them and not regardless of the temperature whereat the boiler is tuned.

It just so happens that the hydrogen economy promises an abundant source of pure oxygen gas. Which leads to my question: what will be the most likely/most profitable/most opportune destination for this oxygen, created as a 'residual' product in this economy?

$\endgroup$
5
  • $\begingroup$ that is not an engineering question ... a marketing question at best $\endgroup$
    – jsotola
    May 6, 2023 at 19:04
  • $\begingroup$ Or, the hydrogen economy might provide only carbon. It's not as if either process makes sense at present. A hydrogen cycle providing carbon monoxide is also available, but nobody working on the hydrogen economy wants an abundant supply of carbon monoxide. $\endgroup$
    – david
    May 7, 2023 at 1:09
  • $\begingroup$ @david, which 2 processes are you referring to in your second sentence? Hydrogen from electrolysis and nitrogen-free combustion? $\endgroup$
    – 5th decile
    May 7, 2023 at 9:55
  • $\begingroup$ The hydrogen economy (as generally envisioned) is oxygen neutral. There is no net production. $\endgroup$
    – Phil Sweet
    May 7, 2023 at 12:48
  • 1
    $\begingroup$ @Vergilus Both catalytic splitting of hydrocarbon feedstock. which includes ordinary steam reforming, which produces carbon monoxide. Replacing ordinary steam reforming with a process that economically produces pure carbon is unlikely, but under active research because it's a process that actually offers realistic carbon capture. $\endgroup$
    – david
    May 7, 2023 at 23:41

2 Answers 2

2
$\begingroup$

It will be sold as valuable chemical feedstock for a broad variety of manufacturing processes (like steelmaking), for use with acetylene as welding gas, and for medical uses.

$\endgroup$
3
  • 2
    $\begingroup$ Steel mills normally have an oxygen plant built to supply them $\endgroup$ May 6, 2023 at 20:04
  • $\begingroup$ @blacksmith37, thanks, will edit. -NN $\endgroup$ May 6, 2023 at 20:30
  • $\begingroup$ I'm sure that if this answer was expanded a bit, I could accept it (I didn't know about the use of pure oxygen in the recycling of scrap steel... and that sounds like they might be using a lot there already... Anyway: adding a bit of quantitative content to this answer would be fantastic) $\endgroup$
    – 5th decile
    May 8, 2023 at 15:54
0
$\begingroup$

oxygen will sit around in the atmosphere waiting to be turned back to water when the hydrogen combusts.

Along with that, I don't see boilers as a viable use for hydrogen. Using electricity to make hydrogen to use hydrogen to make electricity just adds to our losses. If hydrogen takes off, it will be for transportation.

One of the key costs of widespread hydrogen use is its pressurization, storage, and transport. I don't see these costs being increased just to compress and store oxygen, which is essentially free in the atmosphere.

I suppose that co-locating hydrogen production with users of oxygen could be beneficial, but this would be a decimal point. Hydrogen production would be where the use for hydrogen is, not where the use for oxygen is.

$\endgroup$
1
  • $\begingroup$ Sorry for the drive-by down vote, have an offsetting upvote from me. $\endgroup$
    – Phil Sweet
    May 8, 2023 at 20:35

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.