Type S as a Tailsitter Prolate Spheroid

[Spinward Flow]

Obviously, it would seem that starships while processing unprocessed fuel to processed fuel, from unprocessed water, would use siphon off the byproduct oxygen, into a separate tank under pressure.

This is one of my postulates in the regenerative biome life support laboratory house rules that I came up with. Wilderness refueling (oceans, gas giants, etc.) will involve a variety of chemical elements that are "unwanted" in refined liquid hydrogen fuel tankage for use when jumping (and supplying the fusion power plant) ... however, that "waste chemistry byproducts" stream will contain a wide variety of chemical elements that are suitable/necessary for life support functions (with or without the regenerative biome option).

"Waste" oxygen generated by the refining of hydrogen fuel is merely one of the most obvious byproducts of such a fuel purification cycle. There will be plenty of other "waste chemistry" feedstocks generated by fuel purification to generate "refined" liquid hydrogen that is "jump rated" for safety and reliability. Those chemical byproduct feedstocks can either be vented overboard during the fuel purification processing ... or they can be salvaged/harvested/stored for later use (including "proper disposal" at starports as part of the "berthing fees" system of logistical support).

All of this would be "invisible, game mechanically" to how Traveller works as a set of rules for space and interstellar transit ... but it's fun to think of these things in "waste not, want not" terms once you realized that not all locations an interplanetary/interstellar craft might be going to will have "hospitable" environments. One Man's Trash Is Another Man's Treasure and all that. What is plentiful in one location may be especially scarce in another (and therefore valuable, elsewhere).

 

[Condottiere]

I think you'd have to incorporate a, what are we going to term this, ecosystem that actually can process and utilize the byproducts.

I'm not to crazy about the current iteration of the biodome, because optimal return on investment, which means it provides the constant base load of life support for the spacecraft, is really far off in the future, not accounting for damage and destruction, which would require a rebuild.

On the other hand, an empty cargo hold, which costs nothing except hull overhead, that you could funnel these items, and have one crew member with a green thumb, and/or degree in horticulture, to leverage these precious byproducts.

 

[Spinward Flow]

means it provides the constant base load of life support for the spacecraft, is really far off in the future

According to Travellerwiki (LINK), regenerative biome life support is a TL=9 advancement.

By TL–9 Bioregenerative Life Support has been developed.

That's because that branch of the "tech tree" isn't just needed for starship crews, but also for settlements of populations in hostile environments (basically, anything that requires more than a filter mask).

On the other hand, an empty cargo hold, which costs nothing except hull overhead, that you could funnel these items, and have one crew member with a green thumb, and/or degree in horticulture, to leverage these precious byproducts.

Basically the difference between doing it "professionally" with a tested/proven "laboratory" setup ... and doing it as a hobbyist with a homebrew lashup using spare parts that were just lying around (ala "moonshine" distilling). With enough skill, you can make the latter approach work, on an individualized scale ... but if you want to get into the business of mass produced environmental engineering (that is tested and reliable), you're really going to want to go with the "professional laboratory" option ("I reckon").

Yet another example of just because something CAN be done, doesn't necessarily mean it's particularly WISE to do things a particular way.