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If I had a steady and powerful wind source and wanted to run a continuous flow of liquid lead, what method would work best to lift the fluid?

One benefit of this fluid is that the machinery will be well lubricated. The other benefit will be the enormous heat capacity, since the fluid will also drive a heat exchanger on the far end. A drawback would be the difficulty in maintaining submerged components.

A lifting method with the lowest maintenance but the best durability for this very heavy fluid would be needed. This system is deployed on a horribly unforgiving planet.

The total lift probably needs to be done in stages, but the goal is to have one stage able to lift 10m$^3$ of molten lead a height of one meter in one minute. With the exception of the radical operating environment, maybe we actually have pumps like this today?

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    $\begingroup$ (1) You can very obviously have a wheel with buckets lined with graphite or such. (2) Liquid-metal cooled nuclear reactors do actually exist. Including lead-cooled nuclear reactors, e.g. used on the Soviet Alpha-class fast attack submarines. (Famous because they were really fast, capable of over 40 knots submerged, they were so noisy they could be detected across an entire ocean, and featured in the Hunt for Red October.) $\endgroup$
    – AlexP
    Mar 7, 2022 at 22:13
  • $\begingroup$ Pumps to move liquid metal are also used in foundations. The pumps have a relatively small number of parts and are usually simple, problems are usually with oxidation, freezing of the metal, or perhaps chemical compatibility. $\endgroup$
    – UVphoton
    Mar 8, 2022 at 6:12
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    $\begingroup$ the nice thing about your setting is that on a 400°C planet, you do not need to design for the eventuality of the lead solidifying. That removes a whole host of problems. $\endgroup$
    – bukwyrm
    Mar 8, 2022 at 8:43
  • $\begingroup$ IIRC, Linotype machines pumped type metal, but a) it was an alloy with a slightly lower melting point that pure lead, and b) they'd handle very small fractions of a cubic meter (the pot in the one I've been around was a couple liters). $\endgroup$
    – Zeiss Ikon
    Mar 8, 2022 at 15:58

2 Answers 2

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I found two references for real-world pumps designed to move liquid lead.

Both of them are centrifugal impeller designs. In principle, this is an extremely simple design with only one moving part, used for a wide variety of fluids (including water and air) and can be completely enclosed if you like, with the fluid input doubling as the single shaft input. It would be trivial to hook such a pump up to a wind turbine for power.

A screw pump could also be used to lift lead, or any other liquid, without increasing internal pressure, or to boost linear flow in a channel. A seal-free screw pump can also operate with only a single moving part (it's just a tube wrapped into a spiral, and mounted at an appropriate angle), but is a more complex shape to manufacture than an impeller pump.

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There are two ways in my mind.

1. Mechanical way

A very old water wheel method is shown in picture taken from here. The wheel can be turned with a air turbine powered by your 'steady and powerful wind source'.

enter image description here

2. Electromagnetic pump. No moving parts

Electromagnetic pumps work based on Faraday's principle, in which the electrical current (I) interacts with the magnetic field (B) generating the magnetic force (F). Therefore, this in turn controls the liquid metal flow. The liquid metal is passing through a channel of dimensions a x b. (Read here)

enter image description here

According to Faraday's principle

F = B I b

Density of lead = 11343 kg/m3

Mass of 10m3 lead = 113430 kg

Work done to raise 10m3 of lead by 1 meter = mgh = 113430 x 9.8 x 1 = 1111614 joules

Power = Work done / time = 1111614 / 60 = 18526.9 watt = 18.5 kW

To move a column of molten lead of height h up,

Electromagnetic pressure > pressure at the bottom of liquid column

Electromagnetic force / Area = F = BIb / ab > ρgh

BI / a > 11343 x 9.8 x h

BI / a > 111161.4 h

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  • $\begingroup$ Doesn't the electrical conductivity of the fluid factor into this as well? 18.5 MW, that is about the energy this fluid is supposed to carry - was going for 20MW (but there's also heat energy). $\endgroup$
    – Vogon Poet
    Mar 8, 2022 at 15:29
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    $\begingroup$ It is 18.5 kW not MW. The fluid will feel force only when it is a good conductor and current is passing through it. This pump does not work for insulator fluids. "An electromagnetic pump is a pump that moves liquid metal, molten salt, brine, or other electrically conductive liquid using electromagnetism" (en.wikipedia.org/wiki/Electromagnetic_pump) $\endgroup$
    – imtaar
    Mar 9, 2022 at 7:31
  • $\begingroup$ Oh, I see that now. I may need a dozen stages then. $\endgroup$
    – Vogon Poet
    Mar 9, 2022 at 15:04

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