Evaporation Chamber
More actions
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| Operation | |
|---|---|
| Prefab Hash | -1429782576 |
| Prefab Name | StructureEvaporationChamber |
| Construction | |
| Placed with | Kit (Phase Change Device) |
| Placed on | Small Grid |
| Paintable | No |
| Stage 1 | |
| Next Stage Construction | |
| Constructed with tool | Wrench |
| Constructed with item | 2 x Steel Sheets |
| Stage 2 | |
| Next Stage Construction | |
| Constructed with tool | Welding Torch |
| Constructed with item | 2 x Steel Sheets |
The evaporator is a device focused on evaporating fluids by depressurizing them which cools them down by their "Latent Heat" parameter.
It includes a liquid input, a gas output, and a gas connection for the heat exchange gas. You can set the target pressure that controls the chamber pressure.
The flush lever will dump all fluid contents of the evaporator into the local atmosphere, both gas and liquid. It will not dump the connected heat exchange gas which is a separate isolated pipe network.
The evaporation chamber achieves cooling by pumping in the working fluid from the liquid input line into it's internal working chamber. This chamber is held at the set pressure by pumping excess gas out to the gas output. The actual amount of cooling achieved depends on the working fluid and its latent heat parameter.
For example, if Pollutant (X) is used as the working fluid you will see from the Stationpedia entry that it will boil at 1 degree C at 3,275.0K Pa. So if you set the pressure to that exact setting any liquid that enters the device will start boiling once it is above that temperature. The chamber then cools down by the latent heat (which is 2 kJ/mole for Pollutant) as the liquid boils into a gas.
It is often paired with a Condensation Chamber to transfer heat from one system to another.
When the evaporator is turned off it no longer loads liquid from the input, or transfers excess gas to the output, but the chamber continues to equalize with the exchange gas. If not properly managed, this can lead to problems, both as the chamber reaches steady state, and again when the chamber is turned back on and pumps out the excess evaporated gas.
In one example, you could feed an evaporator with liquid Pollutant and set the chamber to 1900kPa. As the gas evaporates, the latent heat is drawn out of the gas in the chamber, cooling it. This is usually used to transfer heat from the exchange gas into the chamber. This can cool the exchange gas to as low as ?180 kelvin? (although the temperature will be different in an active system where the exchange gas is receiving heat from elsewhere).
Failure modes
Ice
It is possible to set the pressure low enough that it cools the gas to the point that it starts to form ice. For instance, an evaporator full of Pollutant at 600kPa can form ice which can accumulate to burst the pipes on the output side. This can be prevented if the exchange gas is warm enough to keep the chamber from approaching the freezing point, but it tends to happen when the system is left unattended and processes slow down. To prevent this, use a pressure setting such that the gas/liquid equilibrium temperature is above the freezing point.
Output gas over-pressure
While unlikely in an active system, it is theoretically possible that the evaporation chamber could pump gas into the output connection that causes pressure to rise until the pipe fails. This is most likely to happen when part of the greater system is deactivated and gas pipes shift into a new equilibrium. The easy solution is to use a Backpressure Regulator to transfer excess gas to storage.
Exchange gas low pressure
Low pressure in the exchange gas connection can limit the speed of heat transfer. 150kPa is a good starting point.
Exchange gas freezing
Make sure that the exchange gas can avoid condensation or freezing should the evaporation chamber achieve equilibrium.