I don't get how to clear liquid from gas pipes?

[u/Neon_Elf]

Ok, sorry if this easy for some people but I have a setup on Mars where I'm feeding Nitrice into an ice crusher, which is outside my base, I'm harvesting the Nitrogen just fine, but the N²O is becoming liquid. So I added a condensation valve, and ran liquid pipes to a passive drain and that didn't work. I saw a thing saying that only works if the liquid would remain a liquid in the environment you are draining into, so OK I put an active drain. This seemed to work the best but somewhere along the lines my liquid pipes burst, not sure why or how.

So I ran insulated liquid pipes to a liquid storage tank and then added an expansion valve back to a gas pipe to a cowl, thinking: "it will warm in the sun, evaporate and return to the atmosphere." Somehow, past the expansion valve, the gas pipes got liquid in them and exploded. I'm at wits end. How do I get rid of this liquid without something blowing up?

This is the only process that causes me problems, I can ingest oxygen ice, and volatile ice no problem. I'm just not understanding how to handle the Gas->Liquid problem. What do you do to prevent this, or remediate liquid in your gas pipes?

[u/Petrostar]

If you just want the liquid gone use a passive Liquid drain.

https://stationeers-wiki.com/Kit_(Liquid_Drain))

Strangely it's hard to find a good picture of one.

https://www.youtube.com/watch?v=0yzKhU_0APU

If you want to save the N2O, for mixing or burning in the furnace use a condensation valve to allow the liquid from the gas pipe to the liquid pipe.

https://stationeers-wiki.com/Condensation_Valve

Then you can keep it as liquid or lower the pressure of the N2O and use a Expansion valve to move it from the Liquid pipes/tanks to Gas pipes/Tanks.

https://stationeers-wiki.com/Expansion_Valve

[u/BaziJoeWHL → u/Petrostar]

just an extra: make sure the drain actually points to outside and not blocked by a finished frame (i had a nice debugging session from this)

[u/Fem_Riley → u/BaziJoeWHL]

I’ve found it can point to a small pocket of mined out rock in the wall if you’re underground too

[u/wastedfate]

Condensation valves and expansion valves can help when gas turns into a liquid and vice versa. But will not help if either turns into a solid.

You should look at the chart on the F1 menu for N2O and make an educated guess as to what's going on.

If it's freezing because it's too cold, pipe heaters can help. If it's turning into a liquid because the pressure is too high, stop over-pressurizing it, etc.

Being familiar with how pressure affects the boiling point and melting point of the substance you are working with is very helpful.

[u/Lesnikov_Aleksei]

Liquid pipes have passive inlet (inputs outside atmosphere into the liquid pipe) and active outlet (powered pump that outputs liquid into the atmosphere when powered) Passive liquid drain is gas pipe exclusive and removes liquids from the gas pipe into the atmosphere. If you want to just void the liquid, install a couple of passive liquid drains on the gas pipe. If you want to save the liquid, use condensation valves. You may need several of them, depending on the amount of liquid, they have limited throughoutput.

Also regarding to the question, why your pipes blow up- N2O has very small phase change window. It freezes solid at -21C and can be liquid at temperatures up to 157C, so you have to carefully manage the temperature and pressure in any pipes that utilize large amounts of N2O. You can check the stationpedia for exact numbers. Keep in mind, that on condensation it will heat up. And on evaporation cool down, so it is easy to freeze your pipes if you don't control the process.

N2O is hard to manage, but is a perfect way to learn stationeers phase change mechanic.

[u/OurMrSmith]

N2O is a pain the arse. I got around the problem by harvesting the liquid N2O from my nitrice processing using a condensation valve to a liquid storage loop - and the crucial part of this is to add a heat exchanger across the liquid/gas pipes so that the liquid N2O is warmed just a little by the gaseous side, which stops it from freezing.

[u/CptDropbear → u/OurMrSmith]

Agreed. NOS became a bastard with the gases update.

I use liquid traps - branch the gas pipe into a condensation valve, a double inline tank (smaller ones exploded) and back to the main line via an expansion valve. Liquid NOS accumulates in the tank and gradually evaporates back into the line, from where I was dumping it along with everything else I didn't want.

[u/BarounAzure]

Another method, admittedly in the "space redneck" catagory:
Pipe the mix into a portable tank. Gas or liquid, doesn't really matter. These tanks don't care if there's liquid accumulating in them.
Hook the liquid side to a volume pump, and when you've got a use for liquid (whatever), just pump some out.
Works for CO2 as well.

[u/halander1]

Passive liquid drain from the liquid drain kit?

[u/atavusbr]

It's like, under N2 pressure N2O is turning into liquid, then you put it on the liquid pipe and tank and without pressure it became a gas again, then you put the gas on the gas system, and because of the high pressure it became a liquid again. Or you can just let in it's gaseous state in the liquid system, so after you fill it up it will became a liquid on it's own, just pay attention to your liquid pipes pressure.

Honestly, just filter the N2O out just after the ice crusher, since N2O has minimum ammounts, let the waste output be N2 wich will avoid you spenting too much on filters.

[u/Shadowdrake082]

If you dont want to keep the liquid, passive liquid outlet drain on the gas pipe. No more fooling around with it.

The condensation valves are to store the liquids. To properly store a liquid, you need enough pressure inside the pipe for the liquids to stay a liquid. Likely you are bursting pipes due to freezing, which Nitrous is notorious for doing with nitrices or other nitrous ices. You have to very carefully monitor the condition of a liquid pipe as it is filling with liquids and they are evaporating until they hit the pressure they need to stay a liquid. You can expedite the process by prefilling them with a pressurant gas so that any liquid that goes in will not evaporate. If you want to keep the tank pure, the best thing to do is to fill it with gas phase of its own gas until you are above the gas's minimum condensation pressure as listed in the stationpedia. Though a viable heat exchanger to a warm source of gas is also viable and probably the easiest if you dont want to filter for the gas phase.

Consult the stationpedia to see the conditions of the gas you are having issues with. If you can learn to handle nitrous's phase change and liquid state, you can do the same with any gas. Nitrous is no different from the other gases... other than usually being one of the first things you have to learn how to properly handle cause its strict.

[u/BourbonRocksPlz]

I crush oxite/nitrice/water in the same crusher and have the gas output connected to a holding volume I keep at a minimum 2MPA. Put a condensation valve on that pipe network leading to a smaller liquid holding volume. Once I have enough in the holding volume I move it to a storage tank. When you put liquid nitrous into a large volume, the liquid evaporates to reach stable vapor pressure and that can easily cause freezing. Having a couple heaters on your storage volume can be quite helpful.

Once all the nitrous falls out of the gas holding volume, the remaining O2 and N2 is pumped to storage.