Thread

1. anigbrowl · 1789601755 · focus · HN ↗

   Salt contains the oil and helps seal small fractures. The rock salt surrounding the SPR’s caverns has extremely low permeability, meaning fluids have very little ability to pass through it. It also doesn’t react with petroleum. Under enormous pressures underground, salt also slowly deforms, which helps close small fractures. The salt itself can therefore contain the oil without a steel-and-concrete tank lining the cavern.

   Oil floats on water, which means pumping water into the bottom of the cavern pushes the oil out. As fresh water is pumped into the bottom of the cavern, the oil gets displaced upwards into a delivery system.

   The more water you pump in, the lower the quality of the oil that's pumped out; we are basically loaning the oil refiners money to buy SPR oil they don't really want. Also, the more water we pump in, the more salt leeches into the water and the more the bottom of the chamber deforms, creating shear forces in the upp walls that lower its overall structural integrity.

   I&#x27;ve posted this before; it&#x27;s a recent report on the status and maintenance of SPR facilities, which is very clearly written and well worth your time if you want to understand the topic better: <a href="https:&#x2F;&#x2F;www.gao.gov&#x2F;products&#x2F;gao-26-106918" rel="nofollow">https:&#x2F;&#x2F;www.gao.gov&#x2F;products&#x2F;gao-26-106918

   1. gruez · 1789605389 · focus · HN ↗

      We can&#x27;t pump saturated salt solution to prevent more salt from being dissolved?

      1. chabska · 1789609814 · focus · HN ↗

         If you&#x27;re gonna build a bunch of tanks on the surface to store that saturated salt solutions, you might as well store the oil in those tanks. The point of this salt cavern system is how little infrastructure it needs to store the huge volume of liquid.

         1. nine_k · 1789613184 · focus · HN ↗

            &gt; as well store the oil in those tanks

            Salt does not burn, unlike oil. It would be sufficient to store dry salt, and prepare the brine during the pumping. Still a lot of hassle, of course.

            1. chabska · 1789622535 · focus · HN ↗

               Please, literally every other country in the world store their petroleum reserve in surface tanks. We have fifty years of experience in designing the safety systems around oil tanks, and the only recent major incidents are from drone strikes in Russia and Saudi Arabia. Just because the US luck out in having the specific geological formation to store oil cheaply doesn&#x27;t mean the alternative is untenable.

               &gt; It would be sufficient to store dry salt

               Absolutely impractical. Storing and moving around solids in the megatons is very difficult compared to liquids that can be pumped. For comparison, the absolute largest solids moving operation in the world is a copper mine in Chile, it moves 300,000 metric tonne of mineral per day. The east-west pipeline in Saudi Arabia can move three times that in liquid, 1,000,000 metric tonne per day.

               1. dd8601fn · 1789630971 · focus · HN ↗

                  This method appears to be, in nearly every way, far better suited for purpose.

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