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Your boil rate is the amount of water that you evaporate off in a given amount of time. If you have 40 gallons of sap you will need to evaporate off 39 gallons of water. At 10 gph it would take 3.9 hours. If you ran that 2% through an RO to 6% you will have 13.3 gallons of concentrate and will need 1.3 hours to boil to syrup. (numbers are just for an example, you actually need 43.5 gallons at 2%)Quote:
Originally Posted by Swingpure
It takes less time to boil with RO because you have less of it. If you have 1000 gallons raw sap to boil for the whole season, well, you have to boil off 975 gallons. If you can boil 10 gallons per hour, you're looking at 97.5 hours of boiling.Quote:
Originally Posted by Swingpure
If you RO to bring that 1000 gallons down to 500 gallons, now you only have to boil 475 gallons. It is still 10 gallons per hour. But fewer gallons. Now you will boil for 47.5 hours.
But if its the same evaporator that does 10 gallons per hour, its 10 gallons per hour no matter what. In fact, if anything, I think the more concentrated would be slightly slower than raw sap because the boiling point is higher.... but basically same.
Thanks for the answers. I do get that the savings in time, is the fact that you might have 50 gallons of concentrate to boil instead of 100 gallons of raw sap, saving half the time and half the wood to boil. There is a little part of my brain that still thinks a solution that has less water in it should boiled quicker than a solution with more water, but I will let that thought disappear and that 10 gallons of concentrate will take me an hour to boil, at a boil rate of 10 gph.
I am interested to see what my boil rate actually will be this year. I took on the advice given to me last year and I will now have a base stack, a straight 8” stove pipe, instead of a 6” stove pipe with a 90° elbow in it, a better pan (but not really an increase in sq inch surface area size), a bigger fire box, more seasoned and smaller wood and perhaps especially the float box, that will keep my sap level at 2” or less. (Often last year the sap level in my steam pans might be 3 to 5” deep). I also learnt last year how much wood to put in at one time and that less can be more.
Last year the locals said it was a slow year for our immediate area. I never had to deal with high volumes of sap on any given day, which likely allowed me to keep my head above water. I think only on one day did I reach 1 gallon of sap per tree a day. This coming year if I get a few days of 2 gallons per day, I will be a very busy man. Last year the taps on buckets did not do well, and I think I hurt myself with the taps on lines having the taps unconsciously at the 6 foot level of the trunk. This year they will be lower around the 4.5 to 5’ mark.
Also this year, I will have 80+ taps on what is ideal conditions for 3/16 line, with a steep slope the entire length of the 500’+ line, with a long uninterrupted steep run to the barrels. This should create pretty good natural vacuum, and it will all be with new line and new fittings.
Now I just need the new pan, float box and base stack to arrive and away we go. I guess also wait for March for the sap to flow.
I think I figured out what is tripping you up... and you are onto something. You only have to boil away what isn't syrup. So if you have 10 gallons of sap at 2%, you only have to boil away 9.75 gallons of that, at 10gph. If you have 10 gallons of sap at 4%, you only have to boil away 9.5 gallons of that, at 10gph. If you have 10 gallons of sap at 8%, you only have to boil away 9.0 gallons of that, at 10gph. So, yes, there is less to boil... but as you can see, for practical estimating purposes, you can still round to 10 gallons for easy math unless you're doing super high brix RO. But technically if you like doing math you could subtract the resultant syrup from your gallons to find out how much you actually have to evaporate.Quote:
Originally Posted by Swingpure
But I also suspect that this slight difference will be eaten away, at least partially, by the higher boiling point of the higher concentration, so might as well still stick to calling 10 gallons of sap 10 gallons on your 10gph setup and still keep the math easy.
As others have said, no, this is not correct. The evaporation rate of your rig will remain pretty much close to the same whether you're boiling raw sap or concentrate.Quote:
Originally Posted by Swingpure
Evaporation (boiling) rate is the amount of water exiting the liquid via evaporation as steam during processing. It is dependent upon the size of the evaporator and the firing rate.
Draw-off rate is the amount of syrup (or near syrup) exiting the pan through the draw-off.
Processing rate is the sum of evaporation rate + draw-off rate.
More about this in Chapter 7 of the new Third Edition of the North American Maple Syrup Producers Manual.
Evaporation rate will remain the same...processing rate (evaporation rate + draw-off rate) will increase somewhat with increasing RO concentration due to the higher draw-off rate.Quote:
Originally Posted by Andy VT
Getting closer to running four lines. The weather has been and will be very rainy. I had 20 to 30 face cords of wood delivered in logs for the first time and it has been hard finding dry periods of time to Buck it up and split it. I had wanted to get it all out of the way before stringing the lines, but that is looking less likely.
Today because it rained all day, I took the opportunity of making 86 drops for the new lines, mostly for the three new lines. I am not positive how many taps I will need, it will depend on how many double tap trees I will have and then decide to tap double. I know I have approximately 78 different trees to tap.
Weather here is cooler than normal and we even have some freezing temperatures and minor snowfall in the forecast, but none of the snow will stay. It will warm up again next Friday. It is a reminder that I need to finish doing any of the little things to get ready for the maple season.
I still have to buy the 400 gpd filter, a second transfer pump and maybe a second RO pump.
I hope to get my new pan, base stack, float box and pan cover in December/January.
I gained access to some additional seasoned wood and will add at least a half face cord to my supply surrounding the evaporator.
Gary, I got it made this year. My wife let me get a wood processor and I received a military discount and did not have to pay any taxes or shipping cost. It came from Florida to Michigan. Can't wait to use it.
Well I am jealous. That would be very sweet.Quote:
Originally Posted by Pdiamond
My Buddy has a tractor that makes his work so much easier, with the lifting and moving of the wood.
I just need it to stop raining.
It's been raining here too. Now we have a big cold front dropping down from Canada, starting tonight with a rain/snow mix thru Wednesday. By the weekend it's going to be mid 60's and sunny.