Need help with activated carbon scrubber

[ultraduster]

So I built my own carbon scrubber using a can and screen mesh to hold the activated carbon in place, but it doesn't seem to be taking any of the odor out of the air because the room still has a strong odor. I think it may be the carbon that I purchased, but I am not certain. I can return the carbon if it is the wrong one.

Here are some pictures of the type of carbon and the setup.

There isn't a lot of carbon in it because I do not think the exhaust fan, which is a CPU fan will be able to suck air through. I've tried it with more, but I don't think it will be able to suck air through it. Any tips?

Here is the activated carbon I am using.

 

[J189RFC]

Re: Need help with activated carbon scrubber.

1 thin layer isn't enough. Most filter have 1-3 inches of activated charcoal, have a large surface area and use an inline fan 4 inches and bigger.

Trust me, do yourself a favour, drop the 200-250 on a small or medium sized one from the store. I wish I had when I started.

 

[ultraduster]

Re: Need help with activated carbon scrubber.

1 thin layer isn't enough. Most filter have 1-3 inches of activated charcoal, have a large surface area and use an inline fan 4 inches and bigger.

Trust me, do yourself a favour, drop the 200-250 on a small or medium sized one from the store. I wish I had when I started.

Unfortunately I can't do that because it is a stealth grow cabinet and it would be too loud and too big.

 

[J189RFC]

Re: Need help with activated carbon scrubber.

Ahhhh ok. Sorry. Add a thicker layer of charcoal. Also it will work better if you are pulling air through the filter instead of pushing it out.

Hope this works!

 

[ultraduster]

I increased the thickness to exactly 1 inch of the can and the fan is at full power, but it still doesn't get rid of the smell =\. And yes it is pulling air through the filter and out, but it still isn't doing much. Do you think it is because of the carbon I purchased?

 

[J189RFC]

Is it old charcoal?

If not, keep adding. Have you looked at some of the DIY carbon filters out there? How To Build an Inexpensive Carbon Air Scrubber? Another couple inches may just do it though.

 

[Filter Phanto]

A couple of things about activated carbon.

1) Virgin Activated Carbon is charcoal which has never been used, which is what will work better in this instance. Re-activated carbon can reach approximately 90% of its original effectiveness.

2)Another consideration is the material from which the charcoal is made. Activated charcoal made from coconut shell, which has a small micro pore structure, works well for the small molecules of air and gas....or smoke!

And finally, purchasing in bulk might be worth consideration. You can experiment with minimum depths for your application until you find the right amount. If it's alright, I'll include a couple of links where you can read more and find what you need.

Read about it more here: Activated Granular Carbon | Virgin Activated Charcoal | Bulk Carbon

And here's a supplier of activated carbon: Activated Carbon - Virgin - Pellets - 4x8mm Pellet.
On this last one, it's more for industrial applications. However, you might be able to get a sample from them.

Good luck!

 

[Dr Fish]

Use a bigger or longer can with two fans.... One pushing and one pulling... Works for airplanes..

These are cheap and work well and will control the speed of 12v fans...
12V-40V 10A Pulse Width Modulator PWM DC Motor Speed Control Switch 13KHz US | eBay

 

[LEDBud]

The problem is your fan is designed for a computer not a carbon filter.

One way I can think of to get a cheap exhaust fan that is designed for duct work is to buy a new *bathroom fan*


They can be had new from $20 bucks to $200 and will vary in CFM performance and the db / sones sound level.
Generally the quieter low sone fans cost more.
A Sone is a measurement used by manufactures that is similar to dbi with the lower number being the quieter.

With your closet the smallest bathroom fan which is 50 cfm should work , you can do the math to check.. If you increase the carbon depth in the filter to 2.5 inches deep (and you should) a cheap 50cfm fan will flow more like 15 or 20 cfm , you need to take that into account when sizing the fan.


CFM means cubic foot a minute , width x height X length of air exchanged per minute.

 

[Ricky Bobby]

I had done the same thing with the pc fan and it had worked fine for smell. Try getting activated carbon from the pet store that looks like "raw" carbon I guess I how I would explain it as if you look at yours it's like compressed pellets where the stuff you want is like irregular pebbles with size from dust particales all the way up to the side of beads. That gets a better filter I believe.

Try to "stack" two or three fans for your exhaust and then use a 90° duct elbow to attach your filter to the fans so the layer of carbon is level with the ground. Make it basically so u cant see any light coming through the carbon and add panty hose to the outside over the screen to hold the very small particles.

Wash the carbon before use. I still haven't found a good way of doing this. It sucks period. It's messy but I'll be damned if the inside of my grow box smells like a Bob Marley concert and the outside smells like clean mountain air.

I Wash by filling panty hose with the carbon and the running water over it and mushing it round with my hands for a while. The water never runs clear but it gets a lit of dust out of it. Then I pour it out of the panty hose onto a t shirt that Iplan to throw away and spread it out and let it dry off. Then it's ready to rock.