Scrubber design idea

***caveseeker7*** · 16th April 2006, 16:36

Quote: (Originally Posted by Joseph Grech)

Azimuth scrubber is very similar in design. It is all made of 316 stainless steel with no issue to condensation inside.

Well, there are no sensors in the loop where condensation would cause an issue.

That beast of a scrubber is beautifully made.

At least in theory a metal cann like the Azi's (at least when placed vertical) might actually aid condensation at a good location. On the PRISM, where the gas path is the same (radial, inside out) condensation occurs mostly on the inside of the bucket, before the gas enters the head and sensor area. A metal cann should actually increase that effect since the metal will likely be colder than the composite.

DepthCharge · 16th April 2006, 18:27

Quote: (Originally Posted by caveseeker7)

Well, there are no sensors in the loop where condensation would cause an issue.

That beast of a scrubber is beautifully made.

At least in theory a metal cann like the Azi's (at least when placed vertical) might actually aid condensation at a good location. On the PRISM, where the gas path is the same (radial, inside out) condensation occurs mostly on the inside of the bucket, before the gas enters the head and sensor area. A metal cann should actually increase that effect since the metal will likely be colder than the composite.

I was planning on placing the scrubber in an aluminum can, just for those reasons. 7 in dia aluminum is pretty cheap. You look at the Insp head after a dive and it looks like someone threw a glass of water on the fittings. The outflow tube however is reasonably dry. So why not remove more mositure if you can where it can do no harm?

***caveseeker7*** · 16th April 2006, 19:58

If you use alu make sure it's thick enough and has a good anodized coating.
Absorbant dust and water make a mean mix, make sure you always clean
the cann after a day of diving or if you had water leaking in. Otherwise even
anodized alu will get damaged over time.

DepthCharge · 16th April 2006, 21:17

Quote: (Originally Posted by caveseeker7)

If you use alu make sure it's thick enough and has a good anodized coating.
Absorbant dust and water make a mean mix, make sure you always clean
the cann after a day of diving or if you had water leaking in. Otherwise even
anodized alu will get damaged over time.

Like I said, Aluminum is fairly cheap. I can also get it anodized fairly cheap....like nothing if I'm not in a rush for it. Of course there's always nickel plating

Gecko · 16th April 2006, 21:52

Quote: (Originally Posted by Gecko)

I think you should double check your food can idea. They are generally tin coated steel cans, not pure tin and the tin often wears off.

The calcium hydroxide does produce acid when in contact with moisture (water), which in turn may react with the metal. I'm not a chemist but I suggest you do a more thorough investigation on calcium hydroxide reactive byproducts if you are going to make a metal cannister.

Let us see the photos when you're done!!

cheers

Opps! Opps! Egg on face..acid=base

robin · 18th August 2006, 14:33

Quote: (Originally Posted by DepthCharge)

I was planning on placing the scrubber in an aluminum can, just for those reasons. 7 in dia aluminum is pretty cheap. You look at the Insp head after a dive and it looks like someone threw a glass of water on the fittings. The outflow tube however is reasonably dry. So why not remove more mositure if you can where it can do no harm?

Hi all, first post here so hope I break no rules of ettiquete.

Just to warn you Aluminium and Sodium Hydroxide solution have a vigorous exothermic reaction liberating hydrogen. Hot hydrogen in a high oxygen environment may spoil your day.

We used to use this reaction to fill balloons with H2 and release them with a time fuse at night. The reaction vessel had to be cooled in a waterbath or the reaction ran away (so did we, boiling NaOH solution is not fun)

16th April 2006, 16:36	#11 (permalink)
*caveseeker7* Who loves ya, baby Current Rebreather/s: Sport Kiss Other Rebreather/s: Prism Topaz Join Date: Jan 2005 Location: Too far from Neverland Posts: 5,556	Re: Scrubber design idea Quote: (Originally Posted by Joseph Grech) Azimuth scrubber is very similar in design. It is all made of 316 stainless steel with no issue to condensation inside. Well, there are no sensors in the loop where condensation would cause an issue. That beast of a scrubber is beautifully made. At least in theory a metal cann like the Azi's (at least when placed vertical) might actually aid condensation at a good location. On the PRISM, where the gas path is the same (radial, inside out) condensation occurs mostly on the inside of the bucket, before the gas enters the head and sensor area. A metal cann should actually increase that effect since the metal will likely be colder than the composite. __________________ Cheers Stefan "Political Correctness is a doctrine, fostered by a delusional, illogical minority, and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.!"
(Offline)

16th April 2006, 18:27	#12 (permalink)
DepthCharge New Member Current Rebreather/s: Inspiration Classic Home Build Other Rebreather/s: Home Build Join Date: Mar 2005 Location: upstate NY Posts: 234	Re: Scrubber design idea Quote: (Originally Posted by caveseeker7) Well, there are no sensors in the loop where condensation would cause an issue. That beast of a scrubber is beautifully made. At least in theory a metal cann like the Azi's (at least when placed vertical) might actually aid condensation at a good location. On the PRISM, where the gas path is the same (radial, inside out) condensation occurs mostly on the inside of the bucket, before the gas enters the head and sensor area. A metal cann should actually increase that effect since the metal will likely be colder than the composite. I was planning on placing the scrubber in an aluminum can, just for those reasons. 7 in dia aluminum is pretty cheap. You look at the Insp head after a dive and it looks like someone threw a glass of water on the fittings. The outflow tube however is reasonably dry. So why not remove more mositure if you can where it can do no harm? __________________ Later, John It's better to beg forgiveness than ask permission
(Offline)

16th April 2006, 19:58	#13 (permalink)
*caveseeker7* Who loves ya, baby Current Rebreather/s: Sport Kiss Other Rebreather/s: Prism Topaz Join Date: Jan 2005 Location: Too far from Neverland Posts: 5,556	Re: Scrubber design idea If you use alu make sure it's thick enough and has a good anodized coating. Absorbant dust and water make a mean mix, make sure you always clean the cann after a day of diving or if you had water leaking in. Otherwise even anodized alu will get damaged over time. __________________ Cheers Stefan "Political Correctness is a doctrine, fostered by a delusional, illogical minority, and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.!"
(Offline)

16th April 2006, 21:17	#14 (permalink)
DepthCharge New Member Current Rebreather/s: Inspiration Classic Home Build Other Rebreather/s: Home Build Join Date: Mar 2005 Location: upstate NY Posts: 234	Re: Scrubber design idea Quote: (Originally Posted by caveseeker7) If you use alu make sure it's thick enough and has a good anodized coating. Absorbant dust and water make a mean mix, make sure you always clean the cann after a day of diving or if you had water leaking in. Otherwise even anodized alu will get damaged over time. Like I said, Aluminum is fairly cheap. I can also get it anodized fairly cheap....like nothing if I'm not in a rush for it. Of course there's always nickel plating __________________ Later, John It's better to beg forgiveness than ask permission
(Offline)

16th April 2006, 21:52	#15 (permalink)
Gecko New Member Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Apr 2006 Posts: 4	Re: Scrubber design idea Quote: (Originally Posted by Gecko) I think you should double check your food can idea. They are generally tin coated steel cans, not pure tin and the tin often wears off. The calcium hydroxide does produce acid when in contact with moisture (water), which in turn may react with the metal. I'm not a chemist but I suggest you do a more thorough investigation on calcium hydroxide reactive byproducts if you are going to make a metal cannister. Let us see the photos when you're done!! cheers Opps! Opps! Egg on face..acid=base
(Offline)

18th August 2006, 14:33	#16 (permalink)
robin New Member Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Aug 2006 Location: Amsterdam Posts: 1	Re: Scrubber design idea Quote: (Originally Posted by DepthCharge) I was planning on placing the scrubber in an aluminum can, just for those reasons. 7 in dia aluminum is pretty cheap. You look at the Insp head after a dive and it looks like someone threw a glass of water on the fittings. The outflow tube however is reasonably dry. So why not remove more mositure if you can where it can do no harm? Hi all, first post here so hope I break no rules of ettiquete. Just to warn you Aluminium and Sodium Hydroxide solution have a vigorous exothermic reaction liberating hydrogen. Hot hydrogen in a high oxygen environment may spoil your day. We used to use this reaction to fill balloons with H2 and release them with a time fuse at night. The reaction vessel had to be cooled in a waterbath or the reaction ran away (so did we, boiling NaOH solution is not fun) Last edited by robin : 24th August 2006 at 17:23.
(Offline)

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode