Automated air cleaner with sleep function

[Kasuha]

This is one of CO2 collecting areas in my base. This device takes care of sending it (and any other gas except oxygen) out for further processing, while it is off most of the time and consumes very little energy if there is nothing to clean.

The pump is connected to the filter which is set to filter out oxygen. The filtered output goes to valve that is set to about 1 g/s (took some fiddling to get that value, moving the screen left/right usually helps achieve different values).

When it gets any gas but oxygen, the gas is sent to the collector pipe on the right and above and the pump proceeds at full speed.

When it gets oxygen, it is sent to the valve and there it blocks the filter output, stopping both the filter and the pump. In my base, the collected oxygen pack is usually 350 or 500 grams and since the valve only releases it by about a gram per second, it takes over five minutes before the pump activates again and gets another pack of gas.

The connection between pump and filter must not be long so the pump doesn't send too many oxygen packets there when it runs out of gases of interest. Length of connection between valve and vent is unimportant, length between filter and valve only plays role when it starts up - once the pipe fills up, the function is exactly the same.

[Saturnus]

Wouldn't a mechanical filter work better in this case?

[Kasuha]

I'm not sure what you mean by mechanical filter.

Edit: looked it up. I don't think it is useful in any way in this case but feel free to show me your design.

[Saturnus]

It lets you eliminate the air filter, and all you need to add instead is an air pipe bridge. I can't see how that's not an improvement?

[Kasuha]

11 minutes ago, Saturnus said:

It lets you eliminate the air filter, and all you need to add instead is an air pipe bridge. I can't see how that's not an improvement?

No, that wouldn't be an improvement. The way it is set up, it runs for a few seconds once every few minutes. You can't achieve that with mechanical filter. If you think you can, show me your design.

[Saturnus]

12 minutes ago, Kasuha said:

No, that wouldn't be an improvement. The way it is set up, it runs for a few seconds once every few minutes. You can't achieve that with mechanical filter. If you think you can, show me your design.

You just use a valve to act as the timer. I really don't see the problem. The valve stops the flow from the air pump and releases it in small packets. The pipe will back up identical gasses to a pressure of 1000g. Set the valve to 10g/s, and the air pump will run for 2-3 seconds every roughly 1½ minutes. Insert the mechanical filter before the timer release valve and oxygen packets will be removed from the flow and not stopping the air pump. 

[Kasuha]

34 minutes ago, Saturnus said:

You just use a valve to act as the timer. I really don't see the problem. The valve stops the flow from the air pump and releases it in small packets. The pipe will back up identical gasses to a pressure of 1000g. Set the valve to 10g/s, and the air pump will run for 2-3 seconds every roughly 1½ minutes. Insert the mechanical filter before the timer release valve and oxygen packets will be removed from the flow and not stopping the air pump. 

Mechanical filter does not block the flow, it only steals whatever gas it is cycling from the main pipe and sends it away. When its output pipe blocks, it stops stealing and everything that's in the main pipe continues straight on. The pump would not stop, it would pump oxygen, sending 10 g/s back through the valve and all the rest through the dump pipe.

[PVD]

1 hour ago, Kasuha said:

Mechanical filter does not block the flow, it only steals whatever gas it is cycling from the main pipe and sends it away. When its output pipe blocks, it stops stealing and everything that's in the main pipe continues straight on. The pump would not stop, it would pump oxygen, sending 10 g/s back through the valve and all the rest through the dump pipe.

So, works like yours, output dioxide until oxygen is reached, sleep, then try work again. Oh, wait, "any gas"... Yes, if you are going to block flow by blocking flow of filtered gas, that solution will not work, you will need to "post process" filter for each gas separately, and also add main loop in order for gasses not to be "dumped", e.g. setup for oxygen + dioxide:

If, your base produce less then 100g dioxide per sec, then yes, it is obviously better use electric filter, but if you setting up some huge coal burning monster and can guarantee that you will have not more than 3-4 in gasses in room, then obviously it's better to use energy-free setup.

And for three gasses...

Hm.. I guess it can be simplified if you will create loop which will contain any "other gas".

[Kasuha]

15 minutes ago, PVD said:

Oh, wait, "any gas"...

Okay, it did not occur to me it can be done this way so you are right, it can be done with mechanical filter. For "any gas" (actually only chlorine and polluted oxygen can be considered in this setup) you would need to add separate filters and the line would be longer, blocking different gases for different times. That should not be a major problem. If the hassle with setting it all up is worth the few seconds of 120 W power savings every few minutes is everyone's choice, I guess.

[PVD]

Yes, by adding all types of "other gases" to the second filter you can achieve the same effect, but how create perfectly flowing line of different gases?

[Saturnus]

I must admit I put a little too much stress on this part of the first post

11 hours ago, Kasuha said:

This is one of CO2 collecting areas in my base.

So I thought that couldn't be too difficult as you'd only have CO2 and O2 to deal with. Maybe polluted O2 in some cases but that could just be treated like pure O2 as it's likely treated elsewhere in the base and the packets would likely be very small so they'd dissipate from the timing valve rather quickly there'd be no need to discriminate between those. If your base also has chlorine and other gasses present in the CO2 collecting areas then yes, the air filter is the better option as you've not yet achieved a stable base although you could add a chlorine filter as @PVD described.

[Kasuha]

4 hours ago, Saturnus said:

If your base also has chlorine and other gasses present

Well, it doesn't. But it's good to have a device ready to deal with such option than to have to build one when problems appear.

PVD's solution works but it's rather complex, tricky to set up for the more annoying gases (chlorine) since you have to route them to it for priming and the energy savings it introduces is negligible. Compared to naive solution with pump and filter running all the time, my solution saves 99.7% of power, his solution saves 99.8% of power. So - what I came with was 99.7% and what we are discussing here is additional 0.1%.

Besides, I already have even more energy efficient solution. It just requires keeping the pump off and switching it on after the gas has collected. The solution I posted actually increases energy demand compared to that - but still from negligible to a little bigger negligible. And I don't have to pay attention to it.

[Kasuha]

12 hours ago, PVD said:

Yes, by adding all types of "other gases" to the second filter you can achieve the same effect, but how create perfectly flowing line of different gases?

Actually, if you manage to prime the filter with exactly one packet of chlorine, one packet of carbon dioxide, and one packet of polluted oxygen, it can filter out all three. Only works with the valve, though, as that makes sure the packet will wait for the right carrier at the bridge.