Getting a room to 0% Relative Humidity

[Deleted]

I am conducting a scientific experiment and need to reach 0% relative humidity (RH) in a box room which is about 5m x 5m x 3m.

I have been looking around but most commercial suppliers cannot guarantee 0% humidity and it is essential that the room is as bone dry as possible at least <5% RH.

Does anyone happen to know any methods by which I can reduce the humidity in the room to 0%? The room has no windows which makes the whole task more difficult :P

Thanks

[Thoughtful Trolli]

line the room with plenty of dry bones of course.

[Daedius]

Buy lots of silica gel and line the entire room with it?

[Deleted]

Vacuum the chamber.
Fill it with whatever mix of gasses you want then.

[Kheirn]

Vacuum the chamber.
Fill it with whatever mix of gasses you want then.

I doubt this is feasible, seeing as the room is larger than my apartment. At 75 m³ we're talking 75000 litres of gas, not to mention the time it would take to create a vacuum.

[Independent voter]

What about heating the room to a very high temperature with electric heaters?

[HumbleDuck]

You most probably can't without spending a fortune.

I doubt this is feasible, seeing as the room is larger than my apartment. At 75 m³ we're talking 75000 litres of gas, not to mention the time it would take to create a vacuum.

Bigger than your apartment? How?

[Deleted]

I doubt this is feasible, seeing as the room is larger than my apartment. At 75 m³ we're talking 75000 litres of gas, not to mention the time it would take to create a vacuum.

I know : I think any attempt at what OP requires is in the level of difficulty of making a vacuum in the room.
Walls are porous to water vapor anyway, and any minor gap (doors?) will have humidity pouring in.

[Noradin]

It sounds practically impossible to do if it is just some random room of that size, especially if you want to pass things into it afterwards.

The only thing I can think of on the top of my head to bring a room of that size to nearly 0% humidity is to get a air-tight bag of that size (doesn't need to withstand any significant pressure), deflate it as much as possible then fill it up with the mixture of gases you want until it is expanded to the dimensions you want, then secure it at the corners.

If you want to enter then you need some kind of airlock based on the same principle. Breathing inside that room without a breathing mask seperated from the air inside the room you want to kep dry is a bad idea anyway. Have some sort of mat underneath and inside to avoid tearing. If you want to bring things inside bag them, evacuate as much as possible, then being them throught the airlock and unpack inside.
If you want something big inside, bag it first, evacuate as much as possible, fill it up with the mixture of gasses you want, to get a smooth outside of the bag, then put it in the bigger bag for your room, evacuate, fill with gases, unback inside.

If the thing you want to bring in is sensitive to pressure and cannot be evacutated simply evacuate carefully as far as it is save (so the bag collapses around it) then fill with gases, repeat both steps until dry enough.

If you bring in materials keep in mind that you can sometimes use temperature changes to get rid of some water.
If at all possible dry everything you want to bring in as much as possible previously. Possibly while bagged.

Have someone who knows what they are doing calculate how stringently you would have to keep to these rules.

You can make these kinds of bags yourself with some simple tools (well maybe not the big one with the airlock), it is not that complex, but it will cost a bit of money if you want to check for tightness the professional way (detecting Helium leaks).


This is a very simple concept and the things that get consumed in the process are all cheap.
If your volume is big enough compared to the amount of water contained in whatever you want to have inside it all you really need is a bag, a vacuum cleaner, and nitrogen in gas containers.

WARNING: Handling Nitrogen in a room without windows comes with the danger of suffocation!
Make sure you have someone who knows what they are doing check your implementation of this idea.

[Kaleredar]

I would think that any experiment that would require absolutely ZERO percent humidity would likely require some sort of room designed specifically to emulate precise environmental conditions, rather than trying to turn some spare room into an absolutely, 100% humidity-free zone.

And I'm talking like rooms they make microchips in or where they assemble planetary probes. Not something you could just assemble on the fly.


It sounds like you're being given a hypothetical question to solve given some form of equation in which plugging in a zero percent humidity variable is practical. Either that, or whomever is assigning you the task of this experiment should give you an adequate space in which to test it, rather than expecting you to concoct one yourself.


Long story short: I doubt whatever it is you're testing for funzies ACTUALLY requires zero percent humidity.


...Unless you're playing with alkali metals for some reason and don't want them to react to the moisture in the air. To which I'd ask... why the hell are you playing with Alkali metals.

[Noradin]

Even in lithium battery construction they are working at 1-2%. Below that is not practically possible at this point.

To be fair, he stated it needed to be "near 0%" not "0%" and later he gave "<5%" as limit. That certainly is possible with enough efford.

We do not know enough about what kind of means he has at his disposal and what he wants to do in detail, so brainstorming might possibly help him.

Thus: Isolate, reduce volume to a minimum, then fill up with something already dry, and the resulting mixture of gases should have low humidity.

[timaffleck]

We do laser welding in a 0.00...% humidity glove box.
Using nitrogen. Not sure how much we would use. We use a recirculator/scrubber to reduce the amount of nitrogen we actually need and have a massive liquid nitrogen tank in the back loading dock.
Oxygen at 0.1ppm and dew point of approx -110 degrees Celsius.
We got the glove box cheap but you could be looking at 50-100k or more for a proper system, just for a 1x1x0.5m area.
Any reason u cant do the experiment in a small glove box or is it a large piece of machine/you need to be inside at the same time?

[Deleted]

Bigger than your apartment? How?

Was thinking the same thing :P

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OP you can get to around 1% but that's as low as it gets and that is with a room that was constructed to be a dry room. We are talking about metal facing on both sides of the wall, airlocks, air ducts and a powerful dehumidifier. This is not something cheap

Hmmm I see I might be better off building a dry box as opposed to doing it in a room then

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I would think that any experiment that would require absolutely ZERO percent humidity would likely require some sort of room designed specifically to emulate precise environmental conditions, rather than trying to turn some spare room into an absolutely, 100% humidity-free zone.

And I'm talking like rooms they make microchips in or where they assemble planetary probes. Not something you could just assemble on the fly.


It sounds like you're being given a hypothetical question to solve given some form of equation in which plugging in a zero percent humidity variable is practical. Either that, or whomever is assigning you the task of this experiment should give you an adequate space in which to test it, rather than expecting you to concoct one yourself.


Long story short: I doubt whatever it is you're testing for funzies ACTUALLY requires zero percent humidity.


...Unless you're playing with alkali metals for some reason and don't want them to react to the moisture in the air. To which I'd ask... why the hell are you playing with Alkali metals.

Unfortunately the details of the experiment/project are confidential. The room idea was just one that was floating around but reading through the replies I am starting to think that constructing a some sort of box with a smaller volume might be the way to go. I would require access to it but don't need to necessarily get into it to work. In a nutshell I am testing the effects of <5% humidity on certain living organisms.

[ingsve]

If you're doing a scientific experiment, why are you consulting a games forum about it? Don't you have an institution when you can get more professional advice? I would recommend that instead of building your own dryroom you should just find a research group or private company that has a dryroom you can rent time in or something like that.

[Livnthedream]

Just throw some rice on it. Will dry it right out.

[Deleted]

We do laser welding in a 0.00...% humidity glove box.
Using nitrogen. Not sure how much we would use. We use a recirculator/scrubber to reduce the amount of nitrogen we actually need and have a massive liquid nitrogen tank in the back loading dock.
Oxygen at 0.1ppm and dew point of approx -110 degrees Celsius.
We got the glove box cheap but you could be looking at 50-100k or more for a proper system, just for a 1x1x0.5m area.
Any reason u cant do the experiment in a small glove box or is it a large piece of machine/you need to be inside at the same time?

I think I will be going with the option of reducing the volume significantly. I don't need to be inside it to work but i would need access to it. I just had an idea of perhaps constructing a box either from metal or acrylic sheets and having some sort of dry inlet and an exhaust for the moist air and I can just insert a pair of rubber gloves onto the box which give me access to work on whats inside (not sure what it's called but think of Homer Simpson in the opening credits when he is holding that green crystal thingy). That might be more feasible from what I gathered.

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If you're doing a scientific experiment, why are you consulting a games forum about it? Don't you have an institution when you can get more professional advice? I would recommend that instead of building your own dryroom you should just find a research group or private company that has a dryroom you can rent time in or something like that.

You don't ask you don't get. You'd be amazed at the solutions people on forums can come up with. Brainstorming is a wonderful thing

[Noradin]

I think I will be going with the option of reducing the volume significantly. I don't need to be inside it to work but i would need access to it. I just had an idea of perhaps constructing a box either from metal or acrylic sheets and having some sort of dry inlet and an exhaust for the moist air and I can just insert a pair of rubber gloves onto the box which give me access to work on whats inside (not sure what it's called but think of Homer Simpson in the opening credits when he is holding that green crystal thingy). That might be more feasible from what I gathered.

You are describing a glove box.
Look it up and then try if you can rent one or something.

[Kaleredar]

Was thinking the same thing :P

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Hmmm I see I might be better off building a dry box as opposed to doing it in a room then

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Unfortunately the details of the experiment/project are confidential. The room idea was just one that was floating around but reading through the replies I am starting to think that constructing a some sort of box with a smaller volume might be the way to go. I would require access to it but don't need to necessarily get into it to work. In a nutshell I am testing the effects of <5% humidity on certain living organisms.

Well I can tell you already that lack of moisture in the air has no inherent effect on most living organisms of any considerable size. Places like the Atacama desert or Antarctica, which have next to zero percent relative humidity, still have animals and plants that live their just fine.

Extreme temperatures are what makes those areas inherently dangerous; not so much the lack of water in the air. The atacama desert can dehydrate a person swiftly because it's easily over 42 degrees celsius in the daytime causing water and sweat to evaporate. If it was a balmy 21 degrees celsius, it would hardly be an issue.