Passive Drip Filters (w/ existing pressure mechanics)

[LeadfootSlim]

Water Purifiers are great, but it seems odd that they're the only option for filtration. Ditto for Air Deodorizers; they feel like a band-aid. It also feels strange that they do all that huffing and puffing and don't require any power. Looking at these, it seems to me that we could benefit from a "lesser" water purifier device, and a "greater" air purifier device, to add more progression options in solving these problems. Below are two considerations in this vein.

 

Drip Filter

Size: 1x4

Requires: Water Weight

Consumes: Sand, Polluted Water

Produces: Clean Water, Polluted Dirt

Currently, if you put too much water weight on a tile - most notably the floor of a suspended reservoir - that tile will crack and eventually break, flooding the base. This is a really neat mechanic, and it'd be cool if we could harness that somehow. Enter: the Drip Filter!

This low-tech filtration option could supplement or stall for the Water Purifier during the early game, at the cost of designing a reservoir that won't break and having enough excess water to "push" the bottom-most liquid through the filter. This space requirement makes the Drip Filter difficult to spam / scale up, which ultimately makes the Water Purifier a better option later on. It would also operate slowly, making it undesirable for industrial-scale water purification, and would need manual emptying/refilling (much like a Compost or Deodorizer) every few cycles. The Polluted Dirt produced would be enough to fill one Compost, but would occur infrequently enough to make it an unreliable source, unlike the Water Purifier which produces enough to fill two Composts at more regular intervals. A Drip Filter would also consume Sand, competing with the Water Purifier/Deodorizer for a limited resource.

Most interestingly, one could play with the possibility of a Drip Filter breaking under excess pressure, much like normal walls do. That being the case, using one would be a delicate balancing act of water weights and pressures - too high and it breaks, too low and it doesn't squeeze out clean water. Eventually gaining the ability to reinforce the filter with Mesh Tiles would be another hook-in for tech progression.

 

Oxygen Filter

Size: 2x3

Requires: Air Pressure Differential

Consumes: Thistle Fiber, Polluted Oxygen

Produces: Oxygen, Polluted Dirt

Like the Drip Filter, this would piggyback on existing pressure differential calculations made by the game - assuming that it can, or already does, make comparisons between gasses separated by walls, rather than just liquids. Unlike the Drip Filter, its pressure differential would need to be mechanically supplied, creating an indirect Power requirement to its operation.

Since Polluted Oxygen is infinitely produced by various natural sublimation processes (Polluted Water, Slime, Polluted Dirt), whereas Polluted Water is not (except by Natural Gas Generators), it makes more sense to have a renewable solution for Polluted Oxygen. As a result, it would use Thistle Fiber (a more advanced material) as its consumable element. To make things interesting, the Oxygen Filter could be made to only accept emptying/reloading from its back/"dirty" side, requiring one dupe to suffer pathing through Polluted Oxygen periodically to ensure that the rest of the base is protected.

Like the Air Deodorizer, its main purpose would be removing the Polluted Oxygen - not necessarily producing a livable amount of Oxygen for "free".  The Oxygen Filter would only catch Polluted Oxygen - other gas contaminants like Carbon Dioxide, Chlorine, and Hydrogen would get through just fine. Unlike the Air Deodorizer, however, it would be unusable in those hard-to-reach places like access shafts. 

 

Other considerations

To account for the "cheap" nature of these filters, a small penalty could be incurred on them; if they're left for too long without cleaning, they could start leaking their polluted output rather than their clean output.

"Filtration Medium" as a category is currently just Sand. In the future, this could be expanded to Textile Station-crafted filters which require a sizeable amount of Thistle Fiber to produce, while being less durable than their natural counterpart. This allows for a system-wide renewable option at the cost of labor and farming space. The Oxygen Filter could be introduced in the same tier as this product, which in turn would mean that it would be the "high-brow" option, unable to use primitive Sand.

The Oxygen Filter has an indirect power requirement (assuming you pump Polluted Oxygen into a chamber) but could be justified as a powered device by looking at electrostatic air filters. That being the case, there could be a risk of flammability in the event of a short circuit or maintenance lapse/filter clog, since it uses Fiber... but since fire isn't in the game yet, that's a long shot.

TL;DR

Pressure mechanics in this game are cool, so alternative filtration options that use these would be really neat to see so that pressure is a more involved part of the game.

[Fernir]

Textiles machine is late game thing so it should not be used for early game solutions.

[LeadfootSlim]

4 hours ago, Fernir said:

Textiles machine is late game thing so it should not be used for early game solutions.

I never said it should - but it does need more uses. Using it for a later-game upgrade to the Air Deodorizer makes sense in that regard.