Are HDD's a significant consumer of the world's helium, in the scheme of things? I had thought helium was used only in a few bleeding edge drives, and they went to normal air as the tech matured.
Helium drives are basically standard for enterprise hard drives now. The reduced drag force allows for using thinner drive platters (helium drives can hold up to 10 platters, while air-filled drives can only hold up to 6 platters) which boosts capacity. Helium drives also use less power, run cooler, and the helium gas helps to absorb vibrations that can cause wear and tear (useful in enterprise settings where you have 45 or more drives in a 4U chassis).
Yep, it says right there that a "standard" helium tank is adequate to fill 10,000 hard drives. I am going to assume that by "standard" they mean 220ft^3 or 250ft^3, even though my "standard" for tanks is 125ft^3 because I can comfortably carry one of those on my shoulder.
Helium in the atmosphere is almost two orders of magnitude more common than xenon and three times as concentrated than krypton. Both are extracted from air.
Even though He is constantly venting to space, alpha emitters keep replenishing it.
Cheap helium from 7% CH4 wells is not going to last. But we're not going to run out of He. Just the energy to extract it.
Assuming a drive contains helium at standard temparature and pressure, and contains about a liter in volume. That would be about 1 gram worth of helium per drive.
0.05 gram Helium assuming: (1) half of drive volume is used for platters, (2) at 15° Celcius (3) at 1 atmosphere (I'm guessing not pressurised since that would defeat purpose of using Helium, although might be less than 1 atmosphere)..
0.376 litres for total 3.5-inch HDD volume from my first Google result: "Width: 101.6 mm, Height: 25.4 mm, Length: 146 mm". Actual volume used for platters is less than that.
Helium is light ~ 0.169 g/litre from "0.169 kg of Helium is 0.999 m3 at 15°C": https://microsites.airproducts.com/gasfacts/helium.html Note that I think comment assumed one litre of normal air not Helium: "The density of dry air is 1.2929 g/litre at STP".
GE says over its lifetime (roughly 13 years) an MRI machine will use about 1e4 litres of liquid helium. Two thousand litres is a good estimate for the capacity of a machine, but it's not a useful figure unless you know how often you need to replenish it.
