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A comment on Cargo ships that sink when their cargo suddenly liquefies. Parent comment

Re:Cargo ships that sink when their cargo suddenly liquefies by chillydawg on Friday August 31, 2018 @07:57AM (#17884775)
The usual solution, as with petrol tanks in cars and elsewhere, is to use baffles. It effectively turns one large tank into several smaller ones and stops the liquid from freely sloshing from one side to another. The sloshing causes problems non-linearly with size of tank, so reducing one tank into 4 or 8 has a huge impact on the risks of sloshing. The partitions/baffles are always vertical (although I expect aerospace baffles are a bit more fancy).
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Re:Cargo ships that sink when their cargo suddenly liquefies by gnode on Friday August 31, 2018 @09:28AM (#17885378)
I imagine a problem with that solution is that most of the time, the solid isn't behaving as a liquid. The partitions / baffles may complicate unloading, as you can't just pipe the solid out; a conveyor belt is typically used.
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Re:Cargo ships that sink when their cargo suddenly liquefies by MPSimmons on Friday August 31, 2018 @10:31AM (#17885877)
Can we intentionally liquifact the solid into a liquid?

Also, we can have articulated baffles that raise into place from below, cutting into the solid material.

I think this is a solvable problem.

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Re:Cargo ships that sink when their cargo suddenly liquefies by VLM on Friday August 31, 2018 @10:47AM (#17885996)
But, if the engineering and financial cost of "fixing" transport is higher than the cost of simply moving the bauxite processing plant to the bauxite instead of moving the bauxite to the plant...

Murphys Law is someone will put an aluminum smelter pot on a nuclear powered ship, during a storm the molten cryolite will slosh out of the pot freezing onto one side of the ship, sinking the ship, and we're right back to where we started.

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Re:Cargo ships that sink when their cargo suddenly liquefies by gnode on Friday August 31, 2018 @11:12AM (#17886200)
> articulated baffles that raise into place from below

From where below? My understanding is that the bottom of the tank is the hull.

Although possibly you could put baffles in place, tip the grain, then crane them out for unloading.

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Re:Cargo ships that sink when their cargo suddenly liquefies by donarb on Friday August 31, 2018 @02:26PM (#17887778)
Yanking the baffles out of the hold while the material is still there would be next to impossible. You have tons of weight pressing on them from all sides, not counting the weight of the baffle itself.
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Re:Cargo ships that sink when their cargo suddenly liquefies by MPSimmons on Friday August 31, 2018 @10:29AM (#17885855)
Agreed. I read this and thought, "Oh my God, why not use baffles?"
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Re:Cargo ships that sink when their cargo suddenly liquefies by amelius on Friday August 31, 2018 @08:35AM (#17884983)
Yeah, but the original state of the material was solid. You can't compartmentalize a solid unless you break it.
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Re:Cargo ships that sink when their cargo suddenly liquefies by aunty_helen on Friday August 31, 2018 @08:40AM (#17885020)
Bauxite is pretty much red Australian dirt. It will be carted as small pebbles or a powder. If it was large solid pieces it wouldn't turn to liquefaction.
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Re:Cargo ships that sink when their cargo suddenly liquefies by jsjohnst on Friday August 31, 2018 @08:45AM (#17885066)
Read the article again. Yes, it’s a solid, but a solid more similar to sand or dirt than to a mountain or solid block of metal.
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Re:Cargo ships that sink when their cargo suddenly liquefies by winceschwab on Friday August 31, 2018 @08:43AM (#17885045)
It’s not a true liquid, but rather solid dust mixed with trace amounts of water. Drier than mud, but powder and rock that can shift in a fluid-like way.

It’s like an avalanche or rock slide.

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Re:Cargo ships that sink when their cargo suddenly liquefies by hfdgiutdryg on Friday August 31, 2018 @09:22AM (#17885329)
The article mentions moisture several times, as well as draining moisture during the trip. It also explains liquefaction in terms of water acting on the solid, whereas I always thought it was just about granularity.

From the article, it doesn't sound like it's about trace amounts of water at all. It sounds like water is somehow involved in the loading process...?

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Re:Cargo ships that sink when their cargo suddenly liquefies by Retric on Friday August 31, 2018 @09:57AM (#17885587)
The liquid is simply acting as a lubricant. So, it takes a very small amount to make a large difference. Really it's less soggy than simply damp.
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Re:Cargo ships that sink when their cargo suddenly liquefies by hfdgiutdryg on Friday August 31, 2018 @03:04PM (#17888001)
So why do they mention draining?
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Re:Cargo ships that sink when their cargo suddenly liquefies by NegativeLatency on Friday August 31, 2018 @03:14PM (#17888061)
Or large parts of SF during an earthquake.
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Re:Cargo ships that sink when their cargo suddenly liquefies by maffydub on Friday August 31, 2018 @08:39AM (#17885010)
It was solid, but granular - the article gives the example of crushed ore and mineral sands - so it's already broken up.
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