La Rinconada, Peru is notable because it has an effective oxygen concentration of only 11%, leading to the need for special techniques just to keep a fire going, and preventing the use of combustion-based heat for smelting iron, as they simply can't get hot enough under the oxygen-starved conditions.

However, with today's technology, and a big enough power line and/or natural gas pipe running up the mountain, would it be possible to convert iron ore into crude metallic iron (it only needs to be good enough for an electric arc furnace to use) under these conditions?

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    $\begingroup$ They smelt gold there using combustion so obviously combustion is not that hard. The mercury contamination of the ground water posioning the locals is a bigger hurdle. $\endgroup$ – John May 14 '19 at 14:35
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    $\begingroup$ @John Gold melts around 1900°F. Iron melts around 2800°F. $\endgroup$ – StackOverthrow May 14 '19 at 20:56
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    $\begingroup$ The air of La Rinconada has 21% oxygen just like the air elsewhere. I do not understand what you mean by "effective concentration". I have never heard of a distinction between effective and ineffective concentration. I suppose you meant to say that the oxygen partial pressure is about 0.11 atm instead of the usual 0.21 atm. $\endgroup$ – AlexP May 14 '19 at 21:04
  • $\begingroup$ @AlexP yeah, its basically the same as saying the partial pressure is lower $\endgroup$ – Shalvenay May 14 '19 at 22:08
  • $\begingroup$ @TKK The temprature difference does not make any difference for the question. If you can get sustained combustion to happen you can achieve the desired temprature. $\endgroup$ – John May 14 '19 at 22:19

Yes, just increase pressure

Effective oxygen concentration is low because air pressure is low at high altitude. But oxygen is still ~20% of whatever air you have. The solution to the problem with starting fires is just to increase air pressure in the blast environment.

Given the scale of modern blast furnace operations, a 50% over-pressure in the smelting area is not unreasonable. After all, there are already powerful fans at work; the blast in blast furnace is a blast of hot air sent in through a tuyere. The real changes would mostly be design of the facility to better restrict air flow out of the smelting area, so that the injected air results in a higher pressure region with a suitable oxygen concentration in contact with the molten iron.

  • $\begingroup$ I had never considered the term "blast furnace" before. I never knew they were called that because they used pressurized air, but that makes a ton of sense. $\endgroup$ – JMac May 14 '19 at 19:50
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    $\begingroup$ You do NOT want oxygen in contact with your already smelted, molten iron. The blast furnace needs a sufficiently high temperature so the iron oxide starts reacting with carbon monoxide, and the resulting dioxide reacts with more coal back to monoxide. Once you're there, you don't need much additional air. Blowing oxygen into molten iron is a modern method to make steel, to oxidise residual carbon (and sulfur etc.) $\endgroup$ – Karl May 14 '19 at 22:23

How about using an induction furnace like Cody from Cody'sLab did. You wouldn't need any oxygen at all. It's also not restricted to such low quantities Cody used in his video. According to wikipedia induction furnaces can hold up to 100 tonnes and can even melt steel.

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    $\begingroup$ You need Carbon Monoxide to smelt Iron not just heat, it's a chemical process as much as a thermal one. $\endgroup$ – Ash May 14 '19 at 12:12
  • $\begingroup$ @Ash but that is more a matter of speed, than a "you can't do it" like being unable to get something hot enough (which as other answers point out, is not the case either). There are also plenty of other ways of charging the necessary ingredients. $\endgroup$ – Chris Stratton May 14 '19 at 19:07

Sure, as long as you're willing to pay for bottled or piped gas of some kind, you can run a fuel-air system either using pure oxygen or just compressed air. There's lots of options but you really only need one; a propane burner supplied with compressed air will apparently burn at around 1980°C, Iron smelters only need to get up to 1250°C to reliably reduce ore to metallic Iron, so such a system is more than sufficient. You'll still need to bring in a carbon source feed stock such as Charcoal or Coke to reduce the Iron oxides in the ore.

Short answer: You need to bring in Carbon feed stock as well as Iron ore and you need either piped or bottled gas and/or fuel to run a compressor but it's easily done with modern technology.


You can carry use molten oxide electrolysis to make steel just about anywhere.steel production by Molten Oxide Electrolysis

Even on the Moon or Mars where there isn't any oxygen at all.

  • $\begingroup$ It will not be steel though, just iron. $\endgroup$ – Jan Hudec May 14 '19 at 19:34
  • $\begingroup$ According to this source carbon can be added in as the molten iron cools $\endgroup$ – EstimatorNoiseless May 14 '19 at 20:13
  • $\begingroup$ Yes, of course it can. But it has to be mentioned before you can say it produces steel. $\endgroup$ – Jan Hudec May 14 '19 at 20:29
  • $\begingroup$ @JanHudec -- the question only ever needed to ask for a way of doing primary smelting, as an electric arc furnace can do the rest of the work once you have raw iron metal to play with $\endgroup$ – Shalvenay May 14 '19 at 22:09

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