# Question about scrubber



## Galaxy419 (Nov 25, 2015)

http://goldrefiningforum.com/~goldrefi/phpBB3/download/file.php?id=24791&t=1 
I was wondering if I can add to the last Pcv scrubber a pump that would recirculate from 
Top to bottom like a true scrubber? Also was thinking of using Venturi pump or adding 
Homemade Venturi fitting. My thoughts on adding Venturi would be adding 02 to 
Scrubbing solution . Or would it affect the vaccum I would be pulling with other 
Vaccum


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## Barren Realms 007 (Nov 25, 2015)

The setup you show in the picture will work fine. No need for a venturi.


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## Galaxy419 (Nov 25, 2015)

Thank you for quick reply and the setup will scrub the gasses and not just mask them. I want to be safe as possible. 
My next project will be homemade fume but until then..


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## Barren Realms 007 (Nov 25, 2015)

Make sure you have something in the pipes (marbels or the like) to help the gases to be absorbed into the solution.


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## Galaxy419 (Nov 25, 2015)

I was going to use wiffle golf balls 2/3 way filled of Pcv pipe and hydrogen peroxide in first pipe and sodium hydroxide in other 2. One last question do I have to worry about back flow into reaction? This scrubber design is like pawnbroker Bob 
Ab train and he has one empty flask after reaction. Once again thank you for your knowledge and help!!


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## Barren Realms 007 (Nov 25, 2015)

Wiffle balls are really over sized and you should use something smaller. An empty pipe between your 3rd pipe and vacuum pump would not hurt. Anytime you create a strong vacuum liquid tends to vaporize until the negative pressure equalizes.


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## jeneje (Nov 25, 2015)

This is what I use in my mini scrubber. 
http://www.amazon.com/Black-Aquarium-Filter-Bio-Balls-Filtration/dp/B0055B0LKI

Ken


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## Galaxy419 (Nov 25, 2015)

Thank you barren realms 007 you have been a tremendous help!


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## Galaxy419 (Nov 25, 2015)

And thank you jeneje for all your help


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## MarcoP (Nov 26, 2015)

A safety concern just popped in my mind. Recently Butcher posted an accident report caused by mixing sodium hydroxide with hydrogen peroxide. This type of scrubber use both of them and it is known that backflows can happen.

I initially knew that an empty scrubber right after the reaction vessel could be used to prevent backflows from entering the reactor. Barren Realms wrote, instead, about using an empty scrubber before the vacuum pump to equalize the fumes.

I now start believing that this type of setup would also need an empty scrubber between the peroxide and the hydroxide, am I thinking on the right direction?

Marco


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## kurtak (Nov 26, 2015)

MarcoP said:


> A safety concern just popped in my mind. Recently Butcher posted an accident report caused by mixing sodium hydroxide with hydrogen peroxide. This type of scrubber use both of them and it is known that backflows can happen.
> 
> I initially knew that an empty scrubber right after the reaction vessel could be used to prevent backflows from entering the reactor. Barren Realms wrote, instead, about using an empty scrubber before the vacuum pump to equalize the fumes.
> 
> ...



If you look at the label on the H2O2 container that the guy dumped the NaOH into you will see that the H2O2 was a 50% H2O2 solution so a "VERY" high concentration of H2O2 which is what caused the violent thermal reaction

In the scrubber we are using a "much" diluted H2O2 solution so it should not be a problem

Also you can "completely" eliminate the back flow problem by "relieving" the vacuum "before" shutting the vacuum pump off --- the back flow problem happens because your reaction vessel is "under" vacuum so when you shut the vacuum pump off the vacuum goes in reverse (back to the reaction vessel) 

I simply pull the hose connected to my reaction vessel to "break" the vacuum before tuning the vacuum pump off & have never had a problem with back flow

Or you can put a bleeder valve in line between the reaction vessel & the scrubber that you open before turning the vacuum pump off

Kurt


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## MarcoP (Nov 26, 2015)

Thank you Kurt, I always thought I should use concentrated H202! However, in the deadly accident the peroxide container was almost empty, this made me think that even small amounts could cause tragic episodes.

Edit: +almost

Marco


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## Barren Realms 007 (Nov 26, 2015)

If you look at his picture in the first post he has an opening in the rubber stopper of his reaction vessel this should keep him from having the backflow problem as well.


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## kurtak (Nov 26, 2015)

MarcoP said:


> Thank you Kurt, I always thought I should use concentrated H202! However, in the deadly accident the peroxide container was empty, this made me think that even small amounts could cause tragic episodes.
> 
> Marco



There was probably a few gallons of the "concentrated" H2O2 still in the bottom of the tote - those large totes "never" completely drain --- a couple (2-3) gallons of H2O2 that is that concentrated is all it would take to go VERY volatile as soon as the NaOH hit it 

Kurt


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## kurtak (Nov 26, 2015)

Barren Realms 007 said:


> If you look at his picture in the first post he has an opening in the rubber stopper of his reaction vessel this should keep him from having the backflow problem as well.



Correct (& that's my scrubber)

Kurt


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## Barren Realms 007 (Nov 26, 2015)

kurtak said:


> Barren Realms 007 said:
> 
> 
> > If you look at his picture in the first post he has an opening in the rubber stopper of his reaction vessel this should keep him from having the backflow problem as well.
> ...



ROFL Ah ok.


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## Galaxy419 (Nov 26, 2015)

Yes Kurtak I used your design to best illustrate what I was thinking. Sorry I didn't ask first and by the way it 
Is a excellent design!!


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## MarcoP (Nov 26, 2015)

Has any of you ever worried about a power loss? How long do you have before the liquid will back flow in the reactor?
For future reference I'm just calculating the risks of running vacuums without a battery backup, or a PTFE non return valve (if exists).

Marco


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## FrugalRefiner (Nov 26, 2015)

MarcoP said:


> Has any of you ever worried about a power loss? How long do you have before the liquid will back flow in the reactor?


Yes. I add an empty container between the reaction vessel and the first scrubber container. Any back flow will simply flow into the empty vessel. 

Dave


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## saadat68 (Nov 7, 2016)

Is there a complete and step by step tutorial topic or source for making a vacuum scrubber ? ( I searched, all of them are venturi design)
http://goldrefiningforum.com/~goldrefi/phpBB3/download/file.php?id=24791&t=1


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