4 ms·

Two naive questions: Does the salt of the actual cavern dissolve in the oil? And does that effect the quality? Are these reserves easy military targets? It wo

Two naive questions: Does the salt of the actual cavern dissolve in the oil? And does that effect the quality? Are these reserves easy military targets? It would seem causing an explosion in one of these would be catastrophic. I can see why this wouldn't be, but I'd like to leave this question as is to promote (fun) discussion.

tobylane 7y ago
They’re up to 1000m deep. I expect that it’s rock salt that needs considerable agitation to free it up, and would be easily sieved.
- rckoepke 7y ago
  You're right that it's rock salt, and while some of it is mined as coal/metal ore is mined, the salt can also be extracted by gently washing it out with water, as is done near Freeport, TX. The oil doesn't do that because while salt dissolves readily into water, it does not dissolve in oil.
beervirus 7y ago
Salt is insoluble in oil.
akiselev 7y ago
Water is a polar solvent which is why it can dissolve polar molecules like salts. Gasoline is a nonpolar solvent so the worst you'd get is particulate matter coming from the walls, which can be physically filtered out - crude oil has to be refined to remove those kinds of impurities already so the infrastructure is ready to go.
rckoepke 7y ago
The salt does not dissolve into the oil, it contains it like a glass contains water. Salt caverns are very interesting for storing all kinds of oil / hydrocarbons / chemicals. Most fluids found naturally in the ground (oil, natural gas, groundwater) are stored in porous rock. Rocks like sandstone seem quite solid on a human scale, but do have microscopic voids which are filled with whatever kind of liquid/gas in their natural state. We drill into this rock and the liquid/gas slowly moves through the pores of the rock and come up the well. After the liquid/gas is removed, the rock still remains, there's not like a giant cavern you could stand in remaining underground...it's just still solid sandstone. Sometimes we can re-use these sandstone/limestone reservoirs after extracting the oil from them. Natural gas storage facilities sometimes set up shop and pump surge/excess natural gas into the empty oil fields in the off season (summer for northern states) and then extract it again in the high season (winter for northern states to heat homes). However, due to these being natural formations, sometimes there are discontinuities in the boundary layers of impermeable rock so that some of the gas leaks out of the reservoir over time. The storage facility says basically "Anyone who can deliver natural gas to this pipeline may store their natural gas with us. We will mix it into the formation with everyone else's gas, and then pump it out later. For every 1000ft^3 you give us, we will give you 900ft^3 back, and charge you $4 for the privilege." Salt caverns are very different! They're not porous. underground there can be immense - up to 2 miles long by 2.5 miles wide, by 1800 feet in depth. Sometimes miners work the salt face like coal mines, but because salt is soluble in water, sometimes it is mined by drilling a small hole into it, then pumping water through the hole and bringing saltwater back up (typically this is the method that chemical plants such as the one in Freeport, TX use to obtain salt/chlorine to make PVC/etc). After washing out a lot of salt using water, there is left an enormous void - a room large enough to park many vehicles. It takes a lot of engineering to make sure you washed out the cavern into a shape that is structurally sound. If geologists determine that the cavern is structurally sound, then they can try filling it with hydrocarbons. Unlike sandstone/limestone formations, salt caverns rarely leak much product out of storage, but the salt is rarely 100% pure (92-98% is common) so some of the other minerals can dissolve into the stored product and needs to be removed...but typically the cost of cleaning the stored product is minimal compared to its value. To answer your military question: Yes and no. Yes, all storage facilities of strategic value are mapped by all world powers and targeted in a WW3 scenario. But you wouldn't generally try to cause an explosion inside one. In fact, a stuxnet-style attack would be somewhat unlikely to be able to, as there's generally no oxygen/air inside the storage caverns. The oil is removed by pumping water below it. A more likely attack would be a conventional or nuclear explosion above ground, knocking out the equipment/pipes needed to extract the oil from the cavern. Other targets of similar or even greater value would include any locations where multiple strategic oil pipelines cross eachother and exchange material flows (e.g. Hattiesburg, MS), or where the refining takes place (e.g. Houston, TX). Even just one pipeline not working unexpectedly can cause noticeable fuel disruptions/shortages, such as when Colonial Pipeline had some accidents in 2016, parts of New England area faced fuel shortages. Also, we have plenty of above-ground oil storage (in typical tanks) in addition to underground storage. However, the strategic petroleum reserves (800 million barrels) are truly massive and dwarf the entire private industry storage in USA (above and belowground combine to 650 million barrels).
- kyuudou 7y ago
  I bet you know about that salt cavern that collapsed at Lake Peigneur[1]. There should be a documentary on youtube where you can see the footage, including a really big boat going "phoomph" into the whirlpool created by the bayou water filling in the cavern. Edit: here's one[2] [1] https://en.wikipedia.org/wiki/Lake_Peigneur https://en.wikipedia.org/wiki/Lake_Peigneur [2] https://www.youtube.com/watch?v=p_iZr2-Coqc https://www.youtube.com/watch?v=p_iZr2-Coqc still blows my mind
dejv 7y ago
The village I was born in sits on caverns like than which are used to store year worth of gas supply for whole country. Back in 70s one of the tower blow up resulting in huge huge gas burner/candle (100 meters tall). No damage or lives were lost but it took army two weeks to handle it (blew it by jet engine). This fire actually happened on my grandma backyard, but no evacuation was needed. In case oil behave the same like gas I would say it is relatively safe.
- 3dprintscanner 7y ago
  Two jet engines mounted on a tank ! https://www.youtube.com/watch?v=j7Ss3BMrscE https://www.youtube.com/watch?v=j7Ss3BMrscE
awalton 7y ago
It's a salt dome underground. You could drop bombs on it for months and not crack the dome. They drilled into a salt dome in Mississippi, placed and detonated a nuclear bomb into it to see "what if". They didn't destroy the dome. It created a nice little pocket of highly radioactive salt that self-capped with melt material. The cavity got bigger, but the salt dome is still intact. That kind of durability is what makes these kinds of structures perfect for geological storage.

tobylane 7y ago

They’re up to 1000m deep. I expect that it’s rock salt that needs considerable agitation to free it up, and would be easily sieved.

rckoepke 7y ago
You're right that it's rock salt, and while some of it is mined as coal/metal ore is mined, the salt can also be extracted by gently washing it out with water, as is done near Freeport, TX. The oil doesn't do that because while salt dissolves readily into water, it does not dissolve in oil.

beervirus 7y ago

Salt is insoluble in oil.

akiselev 7y ago

Water is a polar solvent which is why it can dissolve polar molecules like salts. Gasoline is a nonpolar solvent so the worst you'd get is particulate matter coming from the walls, which can be physically filtered out - crude oil has to be refined to remove those kinds of impurities already so the infrastructure is ready to go.

rckoepke 7y ago

The salt does not dissolve into the oil, it contains it like a glass contains water. Salt caverns are very interesting for storing all kinds of oil / hydrocarbons / chemicals. Most fluids found naturally in the ground (oil, natural gas, groundwater) are stored in porous rock. Rocks like sandstone seem quite solid on a human scale, but do have microscopic voids which are filled with whatever kind of liquid/gas in their natural state. We drill into this rock and the liquid/gas slowly moves through the pores of the rock and come up the well. After the liquid/gas is removed, the rock still remains, there's not like a giant cavern you could stand in remaining underground...it's just still solid sandstone. Sometimes we can re-use these sandstone/limestone reservoirs after extracting the oil from them. Natural gas storage facilities sometimes set up shop and pump surge/excess natural gas into the empty oil fields in the off season (summer for northern states) and then extract it again in the high season (winter for northern states to heat homes). However, due to these being natural formations, sometimes there are discontinuities in the boundary layers of impermeable rock so that some of the gas leaks out of the reservoir over time. The storage facility says basically "Anyone who can deliver natural gas to this pipeline may store their natural gas with us. We will mix it into the formation with everyone else's gas, and then pump it out later. For every 1000ft^3 you give us, we will give you 900ft^3 back, and charge you $4 for the privilege." Salt caverns are very different! They're not porous. underground there can be immense - up to 2 miles long by 2.5 miles wide, by 1800 feet in depth. Sometimes miners work the salt face like coal mines, but because salt is soluble in water, sometimes it is mined by drilling a small hole into it, then pumping water through the hole and bringing saltwater back up (typically this is the method that chemical plants such as the one in Freeport, TX use to obtain salt/chlorine to make PVC/etc). After washing out a lot of salt using water, there is left an enormous void - a room large enough to park many vehicles. It takes a lot of engineering to make sure you washed out the cavern into a shape that is structurally sound. If geologists determine that the cavern is structurally sound, then they can try filling it with hydrocarbons. Unlike sandstone/limestone formations, salt caverns rarely leak much product out of storage, but the salt is rarely 100% pure (92-98% is common) so some of the other minerals can dissolve into the stored product and needs to be removed...but typically the cost of cleaning the stored product is minimal compared to its value. To answer your military question: Yes and no. Yes, all storage facilities of strategic value are mapped by all world powers and targeted in a WW3 scenario. But you wouldn't generally try to cause an explosion inside one. In fact, a stuxnet-style attack would be somewhat unlikely to be able to, as there's generally no oxygen/air inside the storage caverns. The oil is removed by pumping water below it. A more likely attack would be a conventional or nuclear explosion above ground, knocking out the equipment/pipes needed to extract the oil from the cavern. Other targets of similar or even greater value would include any locations where multiple strategic oil pipelines cross eachother and exchange material flows (e.g. Hattiesburg, MS), or where the refining takes place (e.g. Houston, TX). Even just one pipeline not working unexpectedly can cause noticeable fuel disruptions/shortages, such as when Colonial Pipeline had some accidents in 2016, parts of New England area faced fuel shortages. Also, we have plenty of above-ground oil storage (in typical tanks) in addition to underground storage. However, the strategic petroleum reserves (800 million barrels) are truly massive and dwarf the entire private industry storage in USA (above and belowground combine to 650 million barrels).

kyuudou 7y ago
I bet you know about that salt cavern that collapsed at Lake Peigneur[1]. There should be a documentary on youtube where you can see the footage, including a really big boat going "phoomph" into the whirlpool created by the bayou water filling in the cavern. Edit: here's one[2] [1] https://en.wikipedia.org/wiki/Lake_Peigneur https://en.wikipedia.org/wiki/Lake_Peigneur [2] https://www.youtube.com/watch?v=p_iZr2-Coqc https://www.youtube.com/watch?v=p_iZr2-Coqc still blows my mind

dejv 7y ago

The village I was born in sits on caverns like than which are used to store year worth of gas supply for whole country. Back in 70s one of the tower blow up resulting in huge huge gas burner/candle (100 meters tall). No damage or lives were lost but it took army two weeks to handle it (blew it by jet engine). This fire actually happened on my grandma backyard, but no evacuation was needed. In case oil behave the same like gas I would say it is relatively safe.

3dprintscanner 7y ago
Two jet engines mounted on a tank ! https://www.youtube.com/watch?v=j7Ss3BMrscE https://www.youtube.com/watch?v=j7Ss3BMrscE

awalton 7y ago

It's a salt dome underground. You could drop bombs on it for months and not crack the dome. They drilled into a salt dome in Mississippi, placed and detonated a nuclear bomb into it to see "what if". They didn't destroy the dome. It created a nice little pocket of highly radioactive salt that self-capped with melt material. The cavity got bigger, but the salt dome is still intact. That kind of durability is what makes these kinds of structures perfect for geological storage.