Does a hobby RO reduce the amount of sap needed to sweeten the pan?

[eustis22]

by that I mean, does moving from 2% to 9% drop the amount needed by the applicable corresponding percentage?

What? No, I don't yet know how I would do the math but its a big internet.

[n8hutch]

by that I mean, does moving from 2% to 9% drop the amount needed by the applicable corresponding percentage?

What? No, I don't yet know how I would do the math but its a big internet.
For sure, if you took 2% sap and ran it through your ro 2 passes and got to 8% it's going to take 1/4th the amount of sap to sweeten the pan as running 2% sap, after considering what it takes to fill the evaporator.

[BreezyHill]

LMFAO...I love the sacrasium!!!

Better to ask than to not know. We all started somewhere with no knowledge, and most here will share willingly.

If your sap started at 2% sugar then you will have 4% if you remove half the water. Remove that same amount again and you will go from 4% to 8%.

When you boil with 12% rather than 2% it is a huge difference in how long it takes you to boil down.

Our RO is the workhorse of the operation. Second is the vacuum pump as we suck all the sap to the sap house and no more trucking sap from down the road.

[DrTimPerkins]

by that I mean, does moving from 2% to 9% drop the amount needed by the applicable corresponding percentage?

There are two possible ways to answer this....

1. No, it will require the same amount of VOLUME of liquid to fill the pans as it did with sap.
2. Yes, because you're concentrating the sap, the amount of SAP to generate the volume of liquid needed will be considerably higher.

The answer depends upon how you want to look at it, and becomes even more complicated because your gradient will be steeper with concentrate (a long detailed answer is needed, but briefly, the pile of sugar is greater in the backpan with concentrate than with sap, even though the endpoint at the drawoff is the same -- syrup, so the total pile of sugar needed is greater with concentrate than with sap), and your depth might also be adjusted slightly deeper boiling with concentrate. Knowing how much more would be needed would require more information and a bit more math.

[BreezyHill]

Dr Tim I think the question said to sweeten the pan and not to fill the pan. LOL

Straight water could fill the pan but never sweeten the pan if you are looking at just filling it. It is kinda like how many cooks does it take to fill a kitchen joke.

To laugh takes fewer muscles than to frown.

[eustis22]

>ran it through your ro 2 passes

I am assuming this means you take your permeate and run it thru again?

I get the issue with depth.I assumed people maintain their 1-1.5 inches even after concentrating. But increasing my depth makes sense.

[motowbrowne]

>ran it through your ro 2 passes

I am assuming this means you take your permeate and run it thru again?

I get the issue with depth.I assumed people maintain their 1-1.5 inches even after concentrating. But increasing my depth makes sense.

Running out through again means sending the concentrate, not the permeate through the machine again. If you remove 50% the first time you go from 2 to 4%. Run it through again and you should get 8%.

Many of us cooking raw sap with raised flue pans will run our syrup pans at a comfortable 1-1.5", but run our flue pans at 1/4" or less. Just enough sap to cover the flues. I've never cooker concentrate, but it sounds like a little extra margin of error (more liquid in the pan) might not be a bad idea.

[DrTimPerkins]

Dr Tim I think the question said to sweeten the pan and not to fill the pan.

It did....but to sweeten it you have to fill it. :D

[ennismaple]

It will take more or less the same volume of raw sap to sweeten the pans compared to using RO'd sap. The difference is the time (and energy) to get to that first runoff.

My cousins have the exact same evaporator as we do (minor differences in pan geometry). They boil raw sap and we have 2x 8" towers in series. Their first boil of the season was 5 hours to get just a few gallons of syrup. Our first boil was 84 minutes from the first full fire (ignoring the 30 minute "warmup" fire) until we had syrup running off. Once the gradient is established they'll produce 4-5 GPH and we'll run off 20-25 GPH.