&gt;Stuff gets put through pressure chambers like this all over the world, every day.

I doubt anyone’s putting large amounts of material through 500 MPa. If you have any cites, I’d love to see them.

Here’s my back of the envelope calculation to show what I mean.

I got the 500 MPa pressure direct from their patent application, and I’m assuming a tanker truck of milk as the processing volume, since this has to be done on an industrial scale to show a profit.

Let’s assume a spherical vessel because spheres are best (and cheapest) at holding pressure. The internal volume holds 10,000 US gallons, or 37.85 cubic meters. The formula for calculating the thickness of the wall needed is (pressure * radius) / (2 * yield strength of the material).

Let’s further assume that the tank is made of [Grade 23 titanium alloy](https://www.azom.com/article.aspx?ArticleID=9365), which is a really tough material used for building pressure vessels, with a yield strength of 790 MPa. Then, by putting it in the formula, we get a wall thickness of 66 centimeters, which is over 2 feet. So you need to make a pressure vessel **with 2 foot thick titanium walls** to hold the pressure, and we haven’t even started yet. In reality, you have to overengineer these things to provide a safety margin, so it would be even thicker.

Just for reference, this thing would weigh about 300-400 tons and cost a fortune in material alone, not to mention some extremely expensive machining costs.

Moving on, let’s see how much energy is stored in this compressed tank. The formula for calculating the work done in isothermally compressing a fluid is pB * vB * ln(pA / pB) + (pB - pA) * vB, where pB is pressure inside the tank, pA is atmospheric pressure, and vB is the volume of the tank. Plugging in the numbers, we get 142,282 MJ of energy, which is equivalent to **34 tons of TNT**. That would make for one heck of a powerful explosion if the walls failed on the containment vessel.

I tried to be careful with the math, but if I’ve made any errors I’d be glad if someone could point them out to me.