No Grace Under Pressure

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Atmospheric pressure is about 10 N/cm^2, but there are a whole lot of square centimeters on that tanker — the more familiar unit is N/m^2 (Pascals), where 1 atmosphere is 101325 Pa (or possibly even more familiar 14.7 psi).

Various sites showing this have claims about this happening after the tanker had been heated (from steam cleaning), and all the valves shut while it was still hot. One claims frozen (perhaps they mean liquid?) nitrogen being added. Plausible? Heating the tanker to 373K and then letting it cool to ambient should drop the pressure by 0.20 atmospheres. A tanker that’s 2 meters in radius and 10 m long has a surface area of 125.6 m^2, for a total force of 12.7 MegaNewtons. 20% of that is a lot. I don’t think the liquid nitrogen is strictly necessary, but would add to the effect.

The heat of vaporization of liquid nitrogen is 5.56 kJ/mol and its specific heat capacity of the gas is 29 J/mol-K. The volume of 125.6 m^3 means 5600 moles of an ideal gas, requiring 160 kJ/K to cool it down. Each liter of liquid nitrogen (29 moles) takes about 160 kJ to boil off, and then another .84 kJ per degree as the gas heats up from 77K. So ten liters of liquid nitrogen dumped into it will cool it about 20-25 degrees, depending on the starting point of the tanker. So that won’t hurt, but what’s probably more important is that the tanker was built to withstand some pressure difference and we see the catastrophic failure when its critical pressure difference is exceeded. Unlike the kind of test you can easily do with a can where you boil some water inside, seal it and watch it crumple as it cools, because it wasn’t designed to withstand and significant pressure difference.