Could Someone Explain Air Lifts For Me?

[rustybucket145]

I am in the process of planning a budget greenhouse for my backyard. I have heard and read several articles regarding Air Lifts and their efficiency. I am still a little confused over the concept/theroy behind them and exactly how they work. I plan on DIYing the lift if I find it suitable for my application. So over the last few days I have been trying to locate diagrams or detailed pics of Air Lifts. I have had no luck. So I thought maybee someone here in the Aquaculture forum might have some background or experience with them and could give me a few pointers. I come from an Engineering background so a flow diagram or even sketch would go a long way toward me understanding these things.

Here is my situation:

I need to lift (as many gallons per hour) roughly 4'. My system will be a little over 1000gal and I would prefer to have 2-3 seperate Air Lift systems in case of euipment failure. So Ideally 2-3 smaller Air Lifts on seperate circuits instead of one larger.

Will an airlift work under my circumstances? I could decrease the vertical distance (slightly) if needed. What are the efficiency differences between airlifts and mechanical/magnetic pumps?

I am open to ideas/criticism/links/articles as well as anyone who has had experinces (good/bad) with this system.

Thanks To All

 

[rustybucket145]

Anybody?

 

[suzie166]

An airlift is not a lift per se.
It will not lift water from one tank to another.
Think of it as an underground filter.
It's the same principle.

It will move huge amounts of water.
To move huge amounts of water you need to move huge amounts of air.
And that means you'll need a blower.
A blower can power hundreds of airlifts.

I got my blower from a surplus placed for right around $60.
It's been running nonstop for two years.

here is a picture of a couple of my airlifts

Here is a couple of links for you:
http://reefcentral.com/forums/showthread.php?s=&threadid=47741&highlight=air*.

http://www.google.com/custom?hl=en&...irLift&btnG=Search&sitesearch=reefcentral.com

 

[rustybucket145]

Thank you Suzie166


So basically they are mainly for circulating water from the same head height? That makes alot more sense. I was having trouble with the concept that air bubbles alone could lift water any significant distance. So (in my case) I would still need a mechanical pump to circulate water through my sump/fuge but the air lifts could be added for extra circulation within the prop tanks. This would be beneficial b/c my main pump would not have to be as big (therefore saving a considerible amount of $$) because of the extra circulation provided by the air lifts.

Am I correct in these assumptions?

 

[suzie166]

And the light bulb goes on!

yepper it will move a LOT of water at the same head height.

and it is a lot less spendy the a bunch of power heads or a pump!

 

[rustybucket145]

Ok, I had read through that one thread before I posted. It gave some good information but.... Is this the concept: Submerging a section of pvc with holes/section at the bottom for water to enter. Then from your pic it looks like you have an air hose ran into the pipe and submerged to the bottom. Is there an airstone on the end or just open pipe? I guess you can regulate the airflow with an air valve? Could you give me a link or information pertaining to the blower specs that are needed? Do you know what CFM each of your airlifts are running at?

I assume that running a blower is significantly cheaper on the electrical bill than running a pump to move an equal volume of water. Does anyone know of charts that compare the two?

 

[rustybucket145]

guess we posted at the same time, thanks you just answered some of my questions before I even asked. Damn you're good. Scary...

 

[rustybucket145]

Is that 2" pipe in the pic?

 

[suzie166]

the PVC is open on the bottom.
You need a big hole to move that much water.
No airstone just the tubing.
An airlift works better with bigger bubbles then smaller ones.

I will have to dig thru my bookmarks and see if I can find some of the ref and research I did.

The hard part will be finding a blower that is cheap.

Sweetwater blower
You can call them and ask them what you will need!

 

[suzie166]

no its 1 1/2 inch
you have a PM BTW

 

[rustybucket145]

Wow that blower is pretty expensive. I really don't think that I will need one that big. Are there smaller versions? Anybody got a used one they need to get rid of?

 

[ratimpulse]

http://www.thatpetplace.com/Product...ps/T1/F01AA+0047+1110/EDP/49863/Itemdy00.aspx

Would that work for 2 airlifts?

 

[reefann]

I think that Calfo used these airpumps for his tall skimmers in his GH. IRC one would power two 3" diameter skimmer riser tubes, at around five feet. That is a lot more head preassure than an airlift would be so I would assume they could easily handle four outlets. I plan to purchase one soon for my prop systems and see what it can do........