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jrthe3
04-23-2008, 12:07 AM
I remember in high school my teacher boiled water in a vacuum the vacuum lower the boilling point of the water the more vacuum you put on the water the lower the boilling point dose anyone thinkthis couldwork with sap to make syru or maybe to concentrate the sap befor it goes to the evaporator dose anyone think this is possibly or have any in put on this

maplwrks
04-23-2008, 04:06 AM
D&G Is Doing Research On This Now---They Had An Evaporator Built 2 Years Ago That Boiled Under Vacuum.

jrthe3
04-23-2008, 07:31 AM
not tring to look stupid but who is D&G

maplwrks
04-23-2008, 07:46 AM
Dominion And Grimm

Jim Powell
04-23-2008, 07:50 AM
Rotary evaporators: a Swiss company:

www.buchi.com

used to be the "cadillac" of rotary evaporators, and did have some industrial models. Depending up the amount of vacuum you draw, you could boil the sap at fairly low temp. I always like them because their equipment on small scale could be set up to allow the addition of more "sap" in this case while running.

You are such a great ebay 'hawk', maybe you could find a used commerical rig. They have a 50L or 12.5 gallon setup, but if you even had a 2 gallon reciever flask, you could go through 30 - 40 gallons of sap pretty quick, and gang up a bunch of one gallon runs for final evaporation. I'm guessing you'll need some heat to get a little color. Interesting approach!

We'll have to see how D&G comes out!

mountainvan
04-23-2008, 08:12 AM
The late Lew Staats and Cornell had a vacuum evaporator a number of years back. It worked, but was not feasible for maple production due to the complexity of the process/ machine. Just like most of use don't use steam to make syrup because of the whole boiler complexity. There were several articles about vacuum evaporators in the Maple Digest in the 90's.

Haynes Forest Products
04-23-2008, 12:11 PM
The great thing about this hobby/ buisness is that we are always thinking of a better way. That is what got me started as a kid watching the farmer down the road cooking 20 years later I have my own sap shack full of shiny stuff. Every thing we use today is the product of someones idea that eather worked or didnt. Look on any stone fence and you will find a few ideas that didnt work.....but in the sap shack you will see the one that did.SO KEEP ON THINKING AND DREAMING AND THROW THE BUMS OUT THE DOOR THAT SAY ............I DONT THINK THAT WILL WORK. WHY DONT YOU JUST LEAVE IT ALONE WHY ARE YOU ALWAS CHANGING THINGS and my favorite WELL BILL DOESNT DO IT THAT WAY......SCREW BILL IM GOING TO GIVE IT A TRY

mapleack
04-23-2008, 12:35 PM
I've seen several vacuum evaporator setups over the last 15 or so years. Don't ask me to remember exactly where they were at. In both cases they started sap out in the vacuum evap, then finished in a traditonal evap. If you dont expose the sap to a a certain amount of heat and boiling time to create carmelization you'll end up with sweet stuff thats clear and flavorless. I suppose it would be similar to concentrating too high on an RO. My personal take on it would be that an RO would be a lot easier way to get more capacity than messing around with a vacuum evaporator and a traditional evaporator.

ennismaple
04-23-2008, 01:37 PM
I had a manager at a co-op job while in university who mentioned this technology to me more than 10 years ago - I think he referred to it as a flash evaporator (I could be wrong). It would work to increase the sugar content to lower your evaporation costs and boiling time. It would not make syrup - you need heat to create the colour and flavour. If simply removing all the water until you hit 66.5 brix we'd all be running sap through our RO's until we got to the right sugar content. Don't get me wrong, it's a novel idea and I've even researched it myself a bit but it's not the be-all, end-all solution.

lpakiz
04-23-2008, 09:19 PM
You know, I was thinking of this several years ago. Why not pull a vacuum on your clothes dryer to make the moisture evaporate at a lower temp? Of ciurse, the dryer would have to be air-tight. I got the idea from when we would evacuate the A/C system on trucks before adding R-12. (Does this give my age away?) The way the A/C book explained it is that you pull a vacuum of 29.?? inches and that would lower the boiling point of moisture (water) lower than the ambient temp. The moisture would turn to steam @ 65-85 degrees F. and be gone out the vacuum pump exhaust. Not sure how much water can be removed this way per minute (hour) because the A/C book said to leave it on like maybe 1/2 hour for that relatively small and closed system. By adding additional moisture (sap) or starting with gallons of it, might not remove enough per hour to be feasible.
But I like the mentality of thinking outside the box (like the above post said) and not being afraid to advance a theory to the rest of you guys for evaluation....
Larry

jrthe3
04-24-2008, 02:12 AM
I have been reserching this subject for along time and have talk to a lot of people in sience and the maple feild and some have told me that is what you are tring to acomlish with a steam hood on the flue pan it make a draw that will cause A small vacuum dose this sound right to anyone

Haynes Forest Products
04-24-2008, 03:26 PM
A steam hood will only create a draft upward pulling the expanding steam from the evaporator. Like a fire place a good draft only pulls the smoke up the chimney it does not create a vacuum on the wood. Most hoods have alot of leaks around them so they really dont create a vacuum directly to the cooking sap. If you put a air tight hood over a small cooker with a big shop vac. I would bet other than needing a new shop vac in about an hour it wouldnt keep up with the steam that is produced to creat vacuum. But as I said before KEEP DREAMING AND LETS GIVE IT A TRY.

Maple Hill Sugarhouse
04-30-2008, 06:52 PM
post edited

Haynes Forest Products
04-30-2008, 11:14 PM
I think there comes a point when you stop making maple syrup out of maple sap. Im thinkin of having all my sap shipped to the top of Pikes Peak take advantage of the natural vacuum two miles up. I have this old dept. of ag. book and it talks about comercial food producers running sap thru ROs and then freeze drying the consentrate and they ended up with nice clear tastless thick sugar water. Now dont get me wrong Im trying do do more with less but we still need to cook this thing called sap for a little while

Maple Hill Sugarhouse
05-01-2008, 08:22 PM
post edited

Haynes Forest Products
05-01-2008, 10:01 PM
Well what can I say when A sugarmaker from down the road calls and asks if were cookin? and I say "YOUBET" an he tells me he will be over after dinner I know its around noon if he said hes coming over after supper then Ill see him around 630 PM.

Brent
05-02-2008, 03:15 PM
Aside from the flavor issue, I don't think there is any free lunch to be had with a vacuum.

The energy required to vaporize a gallon of water is the same, whether you use an arch or a vacuum. I think the vacuum system might be more efficient. Not much heat loss through a motor and vacuum pump compared to the heat loss up a stack. But you can't cut electricity for free in the forest.

I think the RO is so attractive because the system does not go through a change of state ie liquid to gas (vapor). I think it will be hard to beat the RO.

Haynes Forest Products
05-02-2008, 06:06 PM
Im not against ROs I just cant tell my wife that Im spending 1100.00 on one until she gets the new car. Tell me more about the Merlin ROs they dont look like they could handle more than 20GPH.

Maple Hill Sugarhouse
05-02-2008, 07:07 PM
post edited

Haynes Forest Products
05-03-2008, 12:45 AM
Hey Gov put it all on red and let it ride