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jrthe3
12-04-2008, 01:15 AM
everyone talks about lifting sap with vacuum has anyone tyed to lift sap with conpressed air here is what i was thinking what you all think
http://i367.photobucket.com/albums/oo112/jrthe3/untitled.jpg

Thompson's Tree Farm
12-04-2008, 04:59 AM
My first inclination is to think that it would push sap back the input line as much as out the outflow line. perhaps a valve system to prevent backflow and a float system that allowed pressure when sap reached a certain level??? Thinking out loud here.....Why use air pressure when there is already vacuum available? On a related note. the folks at LaPierre talked me out of their sap lifts yesterday. Said lift should be kept from freezing at night if it is to work properly.

jrthe3
12-04-2008, 08:04 AM
the more i thought about it last night i think with a check valve and a few other valves it may work in the place of a elec. releaser i think i have a project to try out to see how it work

Haynes Forest Products
12-04-2008, 11:02 AM
From the drawing what you have is a collection tank without vacuum. With that idea in mind all you need is a check valve on the incoming sap side. The problem I see is will the tank that you are going to use take the pressure. I would consider how much rise you have to the sap shack or to the bulk tank. Im sure someone has the formula. A tank that will handle high vacuum will not handle high pressure. If the tank sits in the woods will the sap freeze and block the dip tube? would it be better to have the drain out the bottom for total drain?

Maple Hill Sugarhouse
12-05-2008, 07:58 AM
Where's your team mate when you need help??

dano2840
12-05-2008, 08:13 AM
if your pushing air into that tank inthe diagram and if that sap in line is your mainline connected to all of your trees wont it try and push the sap back into the tap hole or is that what you are going to use a check valve to prevent?
if you had a valve on the main line then i dont see a reason why it wouldnt work.
that would be a cool thing to try, if it works PUT A PATENT ON IT!

dano2840
12-05-2008, 08:18 AM
you would need to have some sort of valve on the sap out line because the whole unit would need to be seeled in order to build up pressure to push the sap up the out line, but how would you get that valve on the sap out line to open when the sap came to it and then close when the sap passed to maintain pressure?
if there was no valve on the sap out line then you couldnt build any pressure in you tank to push it out in the first place

Amber Gold
12-05-2008, 08:23 AM
If I'm looking at this properly I don't think a check valve will solve the problem. If there's compressed air pressure on the downstream side of the check valve it will not open to allow sap through. Unless you just want sap to build up in the tank to a certain level, have the compressor turn on to push the sap out over a couple of seconds/minutes, and then have it shut off and allow the tank to fill back up.

Haynes Forest Products
12-05-2008, 09:36 AM
Jrthe3 My head is spinning with the last couple of posts. Swing check on the sap in side and make sure the tank can stand the pressure. BINGO BANGO your done. What you have drawn is a soda keg or a pot type paint sprayer. How big is the tank going to be? is it manualy operated or set up on a float switch?

802maple
12-05-2008, 04:21 PM
My question is. Are you planning on this being a gravity system or a vaccuum system. If it is vacuum it will have to be one whale of a compressor to overcome the vacuum to the system enough to push it any distance in my opinion.

HHM-07
12-05-2008, 04:50 PM
Don't sound workable to me you would need some sort of presure on the sap in side to open the valve you mite have a hard time finding investors in this idea, my thoughts KEEP THINKING and good luck with it

Dick

maple sapper
12-05-2008, 10:22 PM
You definitely would need it to have a sensor of some kink to tell you the sap level has built up. As others have stated you need a check on the inlet side. You could also create some sort of bladder. that way when the tank fills up then the bladder gets inflated and pushes the sap out the exit side and up to where your trying to get it. I would work similar to a water storage tank in a resdential well water system. when the level in the tank got low it would shut off the bladder and it would contract. This would prevent the air from just escaping down the exit line of the tank. It would force it out. With a combination of all the ideas posted below you could make it happen. Gregg

Beweller
12-06-2008, 10:08 AM
The arrangement you and the responders are describing is--or was--known as an "acid egg". It was used to transfer extremely corrosive liquids for which there was no suitable pump. The acid egg was clumsy and energy inefficient.

In the maple industry lifting sap in vacuum systems is accomplished with "sap ladder". Elsewhere it would be known as an "air lift pump" or "bubble pump". For an example, examine an aquarium.

The operating principal is that a column of a mixture of air and water weighs less than a column of water alone. By mixing air and water, the pressure difference needed to lift the water is reduced. In the typical engineering application the pressure difference is supplied by submerging the inlet of the air lift. In the vacuum tubing system the pressure difference is supplied by the vacuum pump. The pressure difference can equally well be provided by an air compressor.

Air lift pumps can operate in three different modes:

* Slug flow, where the gas and liquid flow as seperate slugs.
* Continuous liquid phase, with the gas dispersed as bubbles.
* Continuous gas phase, with the liquid dispersed as droplets.

The sap ladders using 5/16 inch tubing I suspect operate in the slug flow mode, although they may shift to the continuous gas phase mode at times of low sap flow. All engineering designs appear to be based on operating in the continuous liquid phase mode. There are design parameters for these given in engineering hand books.

Unfortuaterly, I know of no design data for sap ladders as such. The Producer's Handbook is strangely silent in this area. A photograph of a hand on a valve is not helpfull in designing a "two pipe sap ladder".

If changing the pressure in the mainline must be avoided, you must have a free surface somewhere. This does not need to be a tank. A standpipe will do the job. Further, the standpipe can be below the ground surface. The air is introduced at the base of the standpipe.

Note that the pressure needed for the compressed air will be a few psi at most, and the volume not large. Some sort of blower is indicated as an air source.

Haynes Forest Products
12-06-2008, 03:06 PM
BEWELLER
Finally someone has put it all in a nut shell that this dumb *** can follow THANK YOU what comes to mind is pressure differential Thanks

jrthe3
12-08-2008, 02:15 AM
i got this idea from one of them air charged water fire ext. with 50 psi it will shot water as high as my shop roof witch is like 25 feet i was thinking of useing this idea on my gravity bush across the road from the sugar house to take sap over the road