Liquefication

[Linwood]

Just came across this - and it got me thinking:

http://www.bbc.com/future/story/20180905-the-cargo-ships-that-liquefy

Would this phenomenon be a hazard for bulk cargo haulers in the Traveller universe? If so, what effect might it have on the ship? My thoughts are running towards handling penalties if the suddenly “liquid” cargo shifts, maybe burst containers/holds if the cargo swells (this was a hazard for grain-carrying ships in the age of sail). Maybe an increased risk of flammability if a cargo like coal is partially ground to powder or if flammable/hazardous vapors are released as a result. Venting to vacuum might be a good way to mitigate the hazard to the ship but might get the group in financial trouble on delivery (“what do you mean 10% of the cargo evaporated?”).

Thoughts?

 

[Reynard]

The environmental influences of a naval vessel and a space or starship are a bit different. Naval ships are subject to gravity as well as constant three dimensional rocking that would cause the material within to 'slosh' while the ship twists and rolls. Normally ships in space are much more stable only affected by acceleration/deceleration and not making radical vector shifts. Space vessels with grav plates also have better control of the mass within.

 

[AnotherDilbert]

Would this phenomenon be a hazard for bulk cargo haulers in the Traveller universe?

It might, but under very specific conditions that we can avoid.

This particular problem can only happen with granulates like fine sand in huge open holds. Treat the cargo as a liquid from the start and break up the hold with baffles and the problem goes away. If we forced the liquefaction it would even be easier to load/unload?


I would assume that cargoes that expand or release gasses would be generally well understood and packaged accordingly. Only new or unknown materials would surprise.

Or of course unscrupulous cargo factors not bothering to follow the safety protocols, hence being barred from reputable carriers has to enlist Free Traders to carry their cargoes...

 

[Reynard]

The problem with baffling is the cargo is not really a liquid and baffles would make loading and unloading far more difficult.

Hauling this type of product in space will be less an issue because gravity is controlled and the pressure issue that would be caused by the weight of the product pressing down can be prevented. Grav plates can be used to direct a bulk product especially fine grain material into a hold then reduce or turn off the gravity during travel. Might not need the water element.

 

[DickTurpin]

Two thoughts come to mind. First, spaceships do not rely on buoyancy to stay afloat. If the cargo shifts, it might require adjusting the engine's thrust to counteract the unequal distribution of mass, but that is about it. Secondly, if water in the cargo is a problem, just remove the atmosphere in the cargo hold. Any water trapped in the cargo will turn to vapor and be pumped out with the rest of the air.

 

[Saladman]

Accepting liquefication as much less frequent, it could be correspondingly surprising and deadly when it does occur. Take a trader making a surface landing in high winds, now they're landing in high winds and unbalanced, and may not even know why.

 

[Condottiere]

Seems somewhat dependent on the empty mass of the ship.

Maybe internal sensors indicating a list.

Perhaps tinkering with the lifters, increasing gravity bite on the opposing side.

 

[Linwood]

So - maybe a Pilot check to compensate accordingly. Difficulty of the check perhaps dependent on when the crew notices the issue or on other external factors - landing under fire or during a severe storm, for example. But once compensated it may be fine.

Effects leading to a volume expansion (again thinking of RL grain shipment issues) might be detectable by internal sensors. It seems reasonable that starships would have some means to monitor strains in the hull to warn of developing conditions that could lead to a cracked bulkhead. Unless a builder goes cheap and just monitors pressure loss?

Temperature - see above. Although I could see an auto-ignition just sort of perking along at a low temp until someone opens the cargo hatch....

Venting off the liquid/vapor - probably easy enough as long as the ship’s well maintained. If not - the normal vents might be obstructed or clogged and venting might require more drastic measures like cracking a hatch. Which might expel a measurable percentage of the cargo as the pressure is released.

Which leads to this thought - if a ship loses some of the cargo it’s contracted to deliver (not speculative cargoes), who pays? Does the ship owner eat the expense and penalties, or can they claim that action was required to save the ship?

 

[steve98052]

. . .
Which leads to this thought - if a ship loses some of the cargo it’s contracted to deliver (not speculative cargoes), who pays? Does the ship owner eat the expense and penalties, or can they claim that action was required to save the ship?

This would be covered by the terms of shipping contract. See GURPS Far Trader, as usual for questions like this.

 

[Reynard]

After decades, centuries or, for the OTU, thousands of years of space and star travel liquification events should be down to a science and technology especially with gravitic manipulation should make ships nearly immune to the effect unless there were a Series of Unfortunate Events to precipitate such an occurrence say... for a story line.

 

[Epicenter]

It sounds like the sort of problem that'd happen on "flexibly" (sloppily) run cargo haulers.

They've had thousands of years (an unthinkably long time, honestly) to refine every small detail of space travel in Traveller. I think any dedicated bulk carrier in the TU would have thoroughly idiot-proofed safeguards to prevent such accidents; they probably still occur but it is extremely rare - the very design of a bulk hauler would keep it from happening by that time.

I think it'd happen a lot more often in smaller haulers, ones that aren't specialized for hauling bulk products, ships that haul whatever they can get their hands on, typically captained by rugged individualists who prize qualities like "independence" and "self-reliance" over "knowledge of physics" or "understanding Ministry of Maritime Safety 0222 'Safely Securing Loose Bulk Cargo.'"

In other words, ship like free traders and far traders -- the kind owned by player characters.

So many of these types are going to just going to dump goods into their cargo spaces, either out of sloppiness or ignorance. There'd be no dividers or anything "fancy" like that because that takes time to set up and it costs some for the dividers. Time is money, you know! What if it shifts...? ...I got a Pilot-3 and an Engineer-3 what do I pay them for? But wasn't it the Engineer-3 who told you to set up bulkheads for this? What are you, a mama's boy from a socialist nanny-state this stuff is hardly worth a thing to haul doing stuff like that will mean my already meager margins will be even more meager!

Yeah, it'd happen. Likely it happens on take-off and landing on worlds where atmospheric buffeting can cause the conditions of vibration and motion. It could also happen on Gas Giant refuelling. Traveller ship hulls are extremely durable, so unless the hull has been compromised I don't think much danger of a hull breach. Interior walls are much less so, especially if the interior layout has been modified - they might burst their holds for instance. This could be hazardous to anyone nearby but mostly I think it'd mean it'd take longer to unload the cargo with a certain loss percentage. The cost of repairing the interior spaces would be pretty high as well. There might be inspections and repairs that need to be made to the anti-gravity and maneuver drive due to the stresses as well. I think the symptoms would be, during re-entry for instance, a high wind buffets the ship one way, the pilot moves the stick to compensate but reports the ship is "fighting" it. He'd probably report that there's something wrong with the gravitics. A call to the engineer says that the gravitics are nominal, but there seems to be an 'asymmetric load' (eg; one side of the ship is noticeably heavier than the other), when the pilot compensates even further, the ship lurches alarmingly and the engineer reports the asymmetric load has shifted to the other side. About this point, the ship starts to groan alarmingly as the sloshing goods start to strain the interior spaces of the ship. There could be a crash if the world has high winds over the landing site and nobody really notices this until they're coming in for their landing approach (because Traveller ships are much more robustly built and powerful than modern aircraft it's likely people do land in hurricane force winds all the time on many planets). Since Traveller ships can land at a much slower speed than modern aircraft (they'd almost all be doing a vertical landing) the damage would likely not be total; it'd be more like a modern ship ramming the quay by accident - the ship would incur damage, as would the port facilities, but chances are nobody would die on the ship.

This is just me, but I can't imagine coal being used for anything in the 57th century, let along being hauled over interstellar distances. Carbon is one of those most common elements in the universe. Carbon and "cheap plentiful fusion power" is going to make coal utterly obsolete - or it should because they could make it themselves using those two. But I guess there are weird situations where it might happen ("Nostros V is a coal-burning TL society, but because they're balkanized one of the nations has been cut off from its coal because of a trade war. They're paying to have it imported" "Why don't they just make their own using fusion and local carbon?" "They need coal imports until that system ramps up."). But coal dust isn't the only thing hazardous. Pretty much any grain does the same thing as does a bunch of other powders become explosive.

 

[Linwood]

Epicenter - that’s where my thoughts were running, only you did a much better job of detailing them!!!

I think there would be some shipments of bulk powders and pelletized raw materials to mid-tech worlds as feedstock for industrial processes. Maybe powdered foodstuffs or ingredients like flour and sugar?

 

[Reynard]

"Carbon and "cheap plentiful fusion power" is going to make coal utterly obsolete"

'Coal' could be a very rare commodity especially a natural coal. Unless worlds have the vast biome and conditions to create it, it won't be a resource. Look at Mars. Same for oil and fossil gas. Alternative energy sources might be the rule on most civilized worlds even well before fusion technology. Gets worst on worlds without geothermal sources, large bodies of water plus a moon or two for tidal power, sufficient atmosphere for windmills or turbines.

Worlds with abundant fossil fuels and access to cleaner energy technologies could do well to sell to worlds without the local ability to handle anything above fire burning fuels. Coal and oil could be a blessing. Earth today could be developing and using far more non-fossil sources for energy and divert its use for non-energy products and even less if we create non-fossil chemicals for products. If we were a space faring world, we could be shipping coal, oil and gas elsewhere as long as we aren't using at all are using far less due to tech alternatives. We don't actually need fossil fuels, it was just easier to run our lower tech societies with such a pure and common material.


So yeah, coal, oil and gas could still be hauled around the universe.

 

[Linwood]

There’s also metallurgical coal - a useful commodity for mid-tech industrial worlds.

 

[Epicenter]

So yeah, coal, oil and gas could still be hauled around the universe.

Oil? Liquified gas? Sure. They're both far more valuable as industrial feedstocks than fuel. If transport fees are low enough, it might be economical enough to move it to use it as fuel, even. Plus they can be used to make coal if someone was that desperate for coal.

Coal? I'm going to have to say no, except for the extreme edge cases; I doubt it'd be a commodity unless transport costs were dead cheap. Coal is basically carbon with some percentage of impurities. These impurities are always bad once the coal is ignited because it ends up as soot and other unpleasant residues, but pure or near pure carbon (graphite) is difficult to ignite, so most coal has some percentage of hydrocarbons in there to make stuff like Anthracite. Carbon should be pretty easy to get a hold of in the form of biomass on any world that could sustain a TL5 (or less) society that seems to be the customers who'd buy coal. Fusion reactor heat + local biomass = carbon, which doesn't take much effort to turn it into a powder. Reform it with hydrocarbons and you have coal or charcoal. One could argue that there might be some extreme desert world with low available biomass and low-tech inhabitants who'd be interested in buying coal ... but admittedly at that point I'd start asking why they're so dead-set on burning coal.

Look at Mars

Who would be burning coal on Mars? You can't live there without a spacesuit. There's no biomass there because there's no biosphere. There's no oxygen to burn the coal.

There’s also metallurgical coal - a useful commodity for mid-tech industrial worlds.

Metallurgical coal is coking coal. Coke is as close as to pure carbon as they can get. Fusion reactors will produce the cheap heat that can be used to reduce biomass to produce nearly pure carbon without coal being involved.

This is honestly another of those "wall of realism" things and where you place that wall. If worlds that are at TL3 just sort of sit there forever for long centuries on end despite an interstellar community that can trade knowledge, technology, and investment (like they appear to in the TU) ... yeah, maybe you'd have these weird situations where some where it's economical to produce synthetic coal -- but I still can't imagine shipping it. It sounds like it's easier to dig it up and ship it rather than make it, but the economic breakdown in this case I think is in favor of shipping hydrocarbons like oil or LNG (which are higher value) and mixing with local carbon to make your synthetic coal.

 

[Condottiere]

It's hard to plead ignorance with instant referencing from whatever wiki is specialized in ship (and cargo) handling.

As regards coal, if they want pure carbon, and have fusion reactors or solar panelling (or both), why not harvest it from the atmosphere?

 

[Reynard]

I've had that daydream many times over. Earth discovers commercial fusion plus possibly commercial scale solar. Coal becomes obsolete as a fuel. Carbon scrubber facilities harvest... carbon all over the planet. It either goes to non energy applications or refill old mines essentially put the genie back in the bottle.

 

[steve98052]

. . . Earth discovers commercial fusion plus possibly commercial scale solar. Coal becomes obsolete as a fuel. . . .

That's one plausible future. But I think the more likely coal capture is that used by the people of the Amazon basin before European diseases killed most of them: biomass captures the carbon, and the biomass is converted to charcoal, which is crushed and used as a soil amendment.

In a future version of that, the plants could be engineered for efficient carbon capture, such as by creating C4 photosynthesis strains for places where C4 works better, and C3 versions for where that is advantageous, or by developing perennial strains of food crops that are normally annuals.

Back to the point about bulk products in Traveller, they would only be practical to ship on either bulk carrier ships, where safeguards against shifting load would be designed into the holds, and in containers aboard flexible-cargo ships. You're just not going to have a bunch of crates of ground car parts, bundles of recyclable wastes, rolls of luxury textiles, and blocks of vitrified radioactives strapped to the floor of the cargo hold with bulk flour filling up the rest of the volume. No, you'd have the flour packed into its own containers too.

 

[Linwood]

“Hey Merl - we got an offer for that grain shipment sitting in Silo 12 but we’re fresh out of grain container modules. What do we do?”

“Darn, we need that silo emptied so we can repair the roof for the upcoming harvest on the AgroSpec farms next week. Who wants to buy?”

“A free trader crew. Newbies - lots of attitude and hardware, not a lot of smarts. I don’t think they know much about the grain trade.”

“Heh. OK, put the grain in standard modules, see if they notice. Give ‘em a 5% discount if they squawk. Make ‘em think they’re getting a bargain!”