Fridge Motor Air Pump

[Ca++]

Rounding up a lot of these ideas, I had another, that I then found existed. I may of even seen it before. A water pump in the tank (bldc so near silent) and a venturi to draw air into the water flow. I have found youtube vids, and amazon sell the venturi's for pennies. It's very much like the microbubble nozzles I can't get, but lower pressure, so you get bigger bubbles. What I have seen uses just a pipe as jetting, but I feel the air could be broke up more, with a gauze to break up the air, without adding a lot of resistance.
I will have to have a play, but this basic idea seems well covered

That seems to work well, just out the box. I don't know where it's from, but I'm interested

 

[420PyRoS]

Venturi systems work good.

Our Emergency bilge system was venturi based. If ingress of water was too much for normal pumps to keep up, we would open venturi lanes off the 10 Bar fire main that would create suction, AKA a venturi, to help remove water.

Air vaccum generators work the same way creating a vaccum from pressurized air or water flowing by.

Typical shape of fluid pressure venturi piping.


Also vaccum generators as well.




Not to mention the irrigation type you have shown. Water/air type.

 

[Ca++]

I gave it a run. 600a3 pump (4 meter head) and a small venturi around 1/4" to match. Results look promising. The air inlet has a spring 1way valve I had to remove, but then the little pump created enough low pressure, to pull in air, turning the water stream white. My bowl was churning around nicely, so still a perfectly good circulatory pump.

Using air stones in my tank, I have the water at atmospheric pressure, with the bubbles passing though. With this venturi and my pump, I have bubbles in water at maybe a 25% higher pressure. My mind is telling me any extra water pressure, will lead to a greater oxygen transfer. Just like putting bubbles into pop. Or conversely, how cavitation pulls gas from fluids. I was told a few posts back, that the swirly machine was giving good oxygenation, and couldn't think why. Maybe, this is it. It's mixing better, at increased pressures.

I have an oxygen test kit around. I will see what I can do

 

[JKD]

If you dissolve air into water under pressure it will generate micro-bubbles when released into atmospheric pressure. This process is used in Dissolved Air Flotation.

 

[Ca++]

The bends can be pretty traumatic, where divers must lower the pressure upon them slowly, or gasses form bubbles within bodily tissue. It's good to put a name to it.

My water had stood for weeks, and it, and my hands, smelt of algae setting this up. 6 hours later

I'm going to call it 12. It's not natural light, but it's past a reasonable 8, and carries pigments past 12. I will check again in the day, and report back if it's different enough. Temps in the goldilocks zone, perhaps 23c

This suggests 8 is all I should expect. Perhaps it is pressure getting me higher, which would be temporary. Which is fine, just as long as it gets delivered.

I have used the kit on tap, to see 8. My eyes calibrated

 

[Drop That Sound]

The Mysterious Discovery of ‘Dark Oxygen’ on the Ocean Floor

Researchers believe they have discovered oxygen being produced 4,000 meters below the sea surface, and think polymetallic nodules—the sought-after bounty of deep-sea miners—could be the source.

www.wired.com

Drop a couple of these bad boys in the res

 

[Ca++]

Is this the pump I'm waiting for?
(the next line is actually an ebay )

12V Brushless Double Head Diaphragm Vacuum Pump Diaphragm Pump PWM Speed Control​

The motor should be about silent, but the pumps are still a similar diaphragm. Each 6L, which is like a decent 3 outlet. It's not the cam I was thinking of though

Nice BB there, showing it's good kit. I'm not entirely sure what I'm looking at though.

Is the bearing sat in a black case, with another behind it? There is a gap between them, where maybe a cam lives. In the first pic, we see the pump heads are at different heights, so likely don't share a cam, like a mirrored pair might. I was hoping for apposing motion for noise cancellation. Is that gold bit really hitting that black plastic, and if so, what about the other side?

£30 used, from a lot of sellers. One claims they come from the states to china, in a stripped state. New ones are 5x the price.

I like that they tick over on 5v, and won't stall at that, if blocked. Obviously there is speed control involved (or not, if you don't want it), and with a total 12L capacity, I can unload that a lot with my 1-2L requirement.

 

[Rocket Soul]

Is this the pump I'm waiting for?
(the next line is actually an ebay )

12V Brushless Double Head Diaphragm Vacuum Pump Diaphragm Pump PWM Speed Control​

The motor should be about silent, but the pumps are still a similar diaphragm. Each 6L, which is like a decent 3 outlet. It's not the cam I was thinking of though

Nice BB there, showing it's good kit. I'm not entirely sure what I'm looking at though.

Is the bearing sat in a black case, with another behind it? There is a gap between them, where maybe a cam lives. In the first pic, we see the pump heads are at different heights, so likely don't share a cam, like a mirrored pair might. I was hoping for apposing motion for noise cancellation. Is that gold bit really hitting that black plastic, and if so, what about the other side?

£30 used, from a lot of sellers. One claims they come from the states to china, in a stripped state. New ones are 5x the price.

I like that they tick over on 5v, and won't stall at that, if blocked. Obviously there is speed control involved (or not, if you don't want it), and with a total 12L capacity, I can unload that a lot with my 1-2L requirement.

The price difference between used and new would have me somewhat suspicious. But 30 bob is a bargain so not much risk for test and assess.

 

[Ca++]

I think they might be from oxygen generators. The kind ill people have. They must be highly reliable (like life depends on it reliable) and owned by a responsible company. One who is maintaining them, and disposing of them.
The other option is air samplers. Where after contamination, it's best to change them.
There is a good sized supply of these on the used market.

I'm a bit reluctant, as it's a 12v 60w psu used. That's likely over 15w even at 5v. As much as pwm can do, it's still a 15w pulse. My 2L AC pump, for example, is 4w (rms, so 6w peaks). I may have to use such pwm, that the current is still rising in the winding, before the pulse ends. Which isn't unreasonable.
I don't have a lot of funds to play with. I can buy what I need, but have to watch what I waste.

Some of the cams used are pretty brutal in vac pump.

Not even any lube.