A gallery of home built hoods and fume scrubbers _hood_

[4metals]

Either of the small scrubbers where the fume passes from vessel to vessel are easily placed outside the hood with a small tube coming in to vent the reaction.

I like @AuggieDog setup with the ported flask bungs. Takes up a little more real estate but i coudl get rid of the clamps.

You will shortly realize the real estate inside your processing hood is in reality precious too!

 

[skinny]

View attachment 63445
Here's the inside of my hood with the scrubber I am using. Hood is 48in x 30x32. The tray in the bottom is disposable and replaceable. The hood is made from Melamine and I built it myself.

does the scrubber vacuum off the fumes directly from the beaker? sorry novice question been spending all night trying to figure them out

 

[Yggdrasil]

does the scrubber vacuum off the fumes directly from the beaker? sorry novice question been spending all night trying to figure them out

For small volumes that is often used.

 

[4metals]

This is a larger hood in a commercial refinery but it still demonstrates one basic method to allow the NOx to be collected and sent through the scrubber. These beakers have had the watch glasses removed because they were ready for the next step. The watch glass directs the fume from the pour spout into the pickup tube.

 

[AuggieDog]

does the scrubber vacuum off the fumes directly from the beaker? sorry novice question been spending all night trying to figure them out

Yes. If you look at that last bit of white tubing dangling free; that piece goes through a watch glass with a hole in the center that fits neatly over a 5L beaker.
The "watch glass" is a glass pot lid from the thrift store with its handle removed (like the photo), these have holes pre-drilled (find one without a vent hole like in the attachment). .

 

[4metals]

The "watch glass" is a glass pot lid from the thrift store with its handle removed (like the photo), these have holes pre-drilled (find one without a vent hole like in the attachment). .

Not exactly, a watch glass is a piece of glass that looks like a mammoth contact lens, no hole in the center. It sits atop the beaker and the pour spout on the beaker creates an opening where the fume can pass between the rim of the beaker and the watch glass. The glass encloses the rim most of the way around except for where the pour spout is. The pot lid pictured above can work if the hole allows the pick-up pipe to draw enough air. And it is placed on the beaker "upside down" from how it goes on to a pot. That allows the condensed fume to drip into the beaker.
This is a catalog cut from a glassware supplier showing a watch glass.
This is a shot of a watch glass on a beaker with an ongoing reaction.
No need to over think this concept, the watch glass sits on the beaker but it is not "sealed". I have also had PVC lids with a hose pickup made but it was overkill and you needed one for every size beaker.
simple is better in this instance.

 

[BGDOCK]

This is a larger hood in a commercial refinery but it still demonstrates one basic method to allow the NOx to be collected and sent through the scrubber. These beakers have had the watch glasses removed because they were ready for the next step. The watch glass directs the fume from the pour spout into the pickup tube.
View attachment 63659

I like the flexible hoses ( looks like my CPAP hoses )do you more details on the plumbing / exhaust duct , that’s a really good idea

 

[BGDOCK]

My first hood
32” high 32” deep 48” wide
Melonite ( 43$ a sheet , two sheets)
Corian counter top (free)
Light LED ( free)
Still working on the exhaust could use some suggestions I have room on the right side
I’m running it 15’ to a 8” round roof penetration

 

[Yggdrasil]

This is a larger hood in a commercial refinery but it still demonstrates one basic method to allow the NOx to be collected and sent through the scrubber. These beakers have had the watch glasses removed because they were ready for the next step. The watch glass directs the fume from the pour spout into the pickup tube.
View attachment 63659

I think I have seen similar but with upside down funnels.

 

[AuggieDog]

Not exactly, a watch glass is a piece of glass that looks like a mammoth contact lens, no hole in the center. It sits atop the beaker and the pour spout on the beaker creates an opening where the fume can pass between the rim of the beaker and the watch glass. The glass encloses the rim most of the way around except for where the pour spout is. The pot lid pictured above can work if the hole allows the pick-up pipe to draw enough air. And it is placed on the beaker "upside down" from how it goes on to a pot. That allows the condensed fume to drip into the beaker. View attachment 63660
This is a catalog cut from a glassware supplier showing a watch glass.
This is a shot of a watch glass on a beaker with an ongoing reaction. View attachment 63661
No need to over think this concept, the watch glass sits on the beaker but it is not "sealed". I have also had PVC lids with a hose pickup made but it was overkill and you needed one for every size beaker. View attachment 63662
simple is better in this instance.

Actually, I was trying to say that my watch glass is a pot lid. I use the hole to feed the hose through that draws up the fumes to the scrubber.

 

[4metals]

I like the flexible hoses ( looks like my CPAP hoses )do you more details on the plumbing / exhaust duct , that’s a really good idea

available from McMaster Carr, I have been using this 1 1/4" hose on setups for years and it holds up exceptionally well. HERE

 

[BGDOCK]

Thanks m familiar w/ that big catalog , I love looking through it
Do you run a scrubber system and a seperate exhaust

CFM requirements for hood

Face dimension x 100 \ 144 = CFM requirements
33x48x100/144=1066 CFM required
Edited for clarity

 

[4metals]

Thanks m familiar w/ that big catalog , I love looking through it

McMaster is amazing, they inventory most of what they list in their catalog and, anywhere in the lower 48 of the USA, they have delivered within 2 days. They have an on-line complete catalog as well. They don't give out those big yellow catalogs as freely as they once did.

 

[BGDOCK]

Oh I better go get mine from the shop , it’s like going through the Sears catalog when I was a kid

 

[BGDOCK]

So I have a couple of questions about this scrubber set up .
1.) Can I start off with just two 5L flasks ( one w/ peroxide and an empty one ) to start off , four 5L flask are 200 $ plus
2.) using an Eductor System McMaster Carr valve 600$ plus ( wife would shoot me) it uses a 8g/min valve . I was thinking of using a submersible pump for the water side possibly little giant pump in a 10-15 gallon container.
Any suggestions or ideas on an affordable educator valve ?

 

[4metals]

Any suggestions or ideas on an affordable educator valve ?

https://flexpvc.com/cart/agora.cgi?p=PVC-Venturi-Tees&p_id=473-825&xm=on&ppinc=detail

flexpvc's venturi's are inexpensive. Put your money into a good corrosion resistant pump

I used the 4 liter vac flasks because I got them for nothing. One of the benefits of being in the refining consulting business. If I were doing it like so many other members I would use 6" PVC rigid pipe with appropriate caps and piping.

 

[Shark]

I have bought a fair bit of glassware from here Tennessee Labware

They keep limited supplies on hand at times so ask when they may have what you may need. I haven’t ordered online but have been in their shop a few times. Seems like decent people to work with.

They don’t have the educator but you might ask to make sure.

 

[4metals]

I drew this up for making the scrubber out of PVC.


If you want I can make up a similar drawing for the vacuum by venturi setup

 

[Shark]

I like the way the ports are on the side, it keeps the cap from dripping when servicing them. Very nice touch.

 

[BGDOCK]

Yes sir that would be great ,