Air lift pump

[zozo]

Lot of us probably know the principle from the Under gravel filter systems..

I want to explore this principle a little in the garden, for fun, with a small solar powered 60l/h airpump.

www.aliexpress.com/item/Solar-Powered-Oxygenator-Aerator-Air-Pump-Oxygen-1L-min-Silent-Solar-Powered-for-Outdoor-Pool-Pond/32959147718.html

This is my actual situation, i have a little less than 40 cm submergence and need to pump 50cm lift. Flow in l/h is not realy important i don't need a massive turnover. I'm already happy as if it would look like an old leaking tap.

I like to explore this to create some turn over but keep the microlife in the tub intact.. And impeler pump would shred all to pieces. that's a no go..And it needs maintenance, air driven doesn't.

Wath kinda boggles me is the ideal tube diameter to make that work with 1 litre air per minute?

Does anybody have experience with this principle? Or does know some explainatory sites. I guess it might be out there somewhere, it is popular in the aqauponic scene.. But yet not found anything realy usefull.

I thought just ask, before i go and buy a bunch of tube sizes and start testing, to reinvent the wheel.. Somebody might know already and has the answer.

Thanks..

 

[zozo]

I think i already found some graph leading me in the correct direction.. It's a print screen from.


According the very first line in the table.. 72l/h air, ¼" tube (6mm) can create 280cm lift at 31cm submergence and 2,4 L/h turnover.. That is quite impressive if i read this graph correctly..

 

[Edvet]

Research the airlifter they sell together with the mattenfilter (i think it's called czech airlifter) These gove very good flow compared to airvolume, and are an easy DIY.

 

[zozo]

Research the airlifter they sell together with the mattenfilter (i think it's called czech airlifter) These gove very good flow compared to airvolume, and are an easy DIY.

Intersting!.. i know the concept..


What i understand from the Air lift pump is if you pump water above the waterlevel than height and diameter need to be in sync with air flow to create the proper lift.
Smaller diameters get higher with less air.. I've tried with a regular small airpump to lift the water up a 12/16 mm hose. With the air outlet at the bottom about 40cm submersed I couldn't get any higher than +/- 10cm above the water level.

Conclusion, there is to little air flow or to big tube diamter in relation to its height. Since my air flow is fixed minimum 1L/m i need to take smaller size tube.

The 25mm tube in the above video seems to have a descent flow, but it probably stops if you go 10 cm higher only resulting in bubbles in the tube. I absolutely need that 50cm head..

What i yet do not understand from the given table from above is: Can it lift up to 280cm head with 6mm tube at 72 l/h air flow at 31cm submersion, or do i "need" 280cm head with 6mm tube to reach 2.4L/h water flow with 72L/h air flow?

I'll give a 6mm tube a try.. I have to test it.

 

[zozo]

It works! 50 cm lift above the water surface and bit less than 40 cm submersion. 6/8mm tube and a Y splitter at the bottom. Small airpump connected and it pushes the water 50 cm up..

Enough to water a plant at least, with a small solar powered air pump.. Didn't yet test it with a 4mm tube.. In theory it should work a tad beter because of the Height and diameter relation. Smaller diameter same height should result in less volume to displace at same lift and same l/h air.. Thus a tad more output.

 

[zozo]

And i can confirm it also works with this little solar powered pump..
www.aliexpress.com/item/Solar-Powered-Oxygenator-Aerator-Air-Pump-Oxygen-1L-min-Silent-Solar-Powered-for-Outdoor-Pool-Pond/32959147718.html

Wonderfull little thing and you barely hear it running from 2 feet away.. The battery specs given are pretty relative to the sun power. But even with a flat battery, this morning 7 o clock, enough light for the pump to start running again. Thus it seems to be a pretty sensitive solar panel it doesn't need a bom of light.

But never mind the battery, i need nothing pumped during the nights anyway. And at some point all batteries reach the end of their load cycle..

For your intrest i made it like this

I gave the rising tube a larger diameter, this makes it easier on the air to take the route of least resistance, in this case up and sucking up water.
Noticed making all the same diameter the air will bubble out the water inlet. It ca be made all same diameter but than put a little bottle neck at the water inlet suction side. A valve or something.

50ml x 60 = 3000ml - 3 l/h That is a desent aquaponic volume to water some plants on a sunny day. Even have little filter capacity for the bucket containing the water with all that drains back. In my case its a Daphnia farm, an impeler pump will suck 'm all in and shred them all to pieces, this does absolutely nothing to them.. This little €20 solar power air pump is a definitve win win..