Sintered pneumatic muffler for bubbling?

[Tony]

This missus is buying me a piston air pump for Christmas, and I remember Julian mentioning something like these for bubbling on a compressor?  This is for bubbling finished bio.

http://www.ebay.co.uk/itm/5-Pcs-1-4-PT-Thread-Sintered-Bronze-Pneumatic-Exhaust-Silencer-Muffler-/290914643758

What was the outcome of that, are they any good?  I've ordered a few and a 1/4" tee (I already have a 4mm to 1/4" male airline adapter) so plan on giving it a go.

At the moment I just have the airline adapter as a weight on the aquarium hose from my old, now dying pump and big bubbles as a result, so hope this will work.

[Julian]

It works really well, but be conscious of blowing potentially moist air into the bio in humid conditions.  I had a coalescing water trap on mine but it never collected any water.

I started building a desiccant dryer ... perspex tube full of silica gel with rolled up plastering scrim at each end to keep it in place.  The tube was probably too smaller diameter as the inlet pipe kept blowing off.  Then I considered the PITA factor of removing and drying the silica gel frequently and never really progressed the idea any further.  In theory it should work.  I might have some photos somewhere if you're interested.

My bubbler in the processor is just one silencer.  I use a similar, single silencer but in an unknown plastic and a very small aquarium pump to do the final drying of my bio.

[Head Womble]

I use two of these on the end of my bubbler and have done from when I first started making bio.
They work well and haven't deteriorated at all.

[nigelb]

I have one of those sintered bronze air dump valves here. Shame you've bought some some Tony. I'd have sent you mine FOC.

If anybody else wants to give one a go...please pm me and I'll send it on.

[photoman290]

It works really well, but be conscious of blowing potentially moist air into the bio in humid conditions.  I had a coalescing water trap on mine but it never collected any water.

I started building a desiccant dryer ... perspex tube full of silica gel with rolled up plastering scrim at each end to keep it in place.  The tube was probably too smaller diameter as the inlet pipe kept blowing off.  Then I considered the PITA factor of removing and drying the silica gel frequently and never really progressed the idea any further.  In theory it should work.  I might have some photos somewhere if you're interested.

My bubbler in the processor is just one silencer.  I use a similar, single silencer but in an unknown plastic and a very small aquarium pump to do the final drying of my bio.
[/quote

you could wrap some nichrome wire around a glass tube nd dry your silica gel that way. calcium chloride works just as well and i cheaper that silica gel. i have a bag somewhere if you want to try some.

[Julian]

It works really well, but be conscious of blowing potentially moist air into the bio in humid conditions.  I had a coalescing water trap on mine but it never collected any water.

I started building a desiccant dryer ... perspex tube full of silica gel with rolled up plastering scrim at each end to keep it in place.  The tube was probably too smaller diameter as the inlet pipe kept blowing off.  Then I considered the PITA factor of removing and drying the silica gel frequently and never really progressed the idea any further.  In theory it should work.  I might have some photos somewhere if you're interested.

My bubbler in the processor is just one silencer.  I use a similar, single silencer but in an unknown plastic and a very small aquarium pump to do the final drying of my bio.

you could wrap some nichrome wire around a glass tube nd dry your silica gel that way. calcium carbonate works just as well and i cheaper that silica gel. i have a bag somewhere if you want to try some.

A good thought that, if I ever resurrect the project, I'll give the nichrome idea some thought.  The silica gel was spare form past (failed) attempts at drying methanol, so no cost really.

Just thinking as I type, what about heating the air with which you bubble?  Hair dryer, paint stripper?

[photoman290]

It works really well, but be conscious of blowing potentially moist air into the bio in humid conditions.  I had a coalescing water trap on mine but it never collected any water.

I started building a desiccant dryer ... perspex tube full of silica gel with rolled up plastering scrim at each end to keep it in place.  The tube was probably too smaller diameter as the inlet pipe kept blowing off.  Then I considered the PITA factor of removing and drying the silica gel frequently and never really progressed the idea any further.  In theory it should work.  I might have some photos somewhere if you're interested.

My bubbler in the processor is just one silencer.  I use a similar, single silencer but in an unknown plastic and a very small aquarium pump to do the final drying of my bio.

you could wrap some nichrome wire around a glass tube nd dry your silica gel that way. calcium carbonate works just as well and i cheaper that silica gel. i have a bag somewhere if you want to try some.

A good thought that, if I ever resurrect the project, I'll give the nichrome idea some thought.  The silica gel was spare form past (failed) attempts at drying methanol, so no cost really.

Just thinking as I type, what about heating the air with which you bubble?  Hair dryer, paint stripper?

opps!! meant calcium CHLORIDE not calcium carbonate

[Jamesrl]

Just thinking as I type, what about heating the air with which you bubble?  Hair dryer, paint stripper?

Ah ye' but don't forget the warmer the air  the more water it can hold,  higher humidity.

[Julian]

Just thinking as I type, what about heating the air with which you bubble?  Hair dryer, paint stripper?

Ah ye' but don't forget the warmer the air  the more water it can hold,  higher humidity.

I was thinking around a heated tube through which you blow the air.  It expands creating a greater capacity for water, but as it's in a flowing tube it won't grab moisture from the air.

[photoman290]

if you used the air from a dessicant type dehumidifier it would be dry. they use a dessicant gel in a rotating drum and use heat to remove the water. it should be fairly easy to direct some of the airflow to a tube for bubbling. you would have to be carefull not to restict the airflow too much or it will overheat. they can be be brought for around £140 new or a lot less than that used.

[Tony]

Piccies:





In action:

http://www.youtube.com/watch?v=LJjWR_h2qdk

[Julian]

That looks quite vigorous compared with mine, but then I've only got a small air pump.  I get distinct, small bubbles rising to the surface which I'd guess would give the largest surface area for the flow available.

Would you be better off with additional sintered silencers?

[nigelb]

This is the one I have and, if suitable, will be on it's way to Will Crosby real soon:

[Julian]

Come to think of it my silencer in the settling tank isn't like the two pictured (although the one in the processor is).  It's a resin/plastic material which has survived bio for over 5 years now.  The surface looks to be quite a bit finer than the sintered brass versions, which may partly explain the difference.

[Tony]

These brass ones you can blow through very easily, no real resistance so I'm not sure it does produce much in the way of fine bubbles.

The pump is one of these:

http://www.ebay.co.uk/itm/35-LTR-PISTON-AIR-PUMP-OFFER-KOI-FISH-POND-QUARANTINE-ACO208-/390730764889

It's the smallest/cheapest of that piston pump range but it does produce a decent amount of air as the video shows.  It's more than I expected to be honest and about 100 times more than the pump I was using, so I don't know how it will affect settling times.