Evap/boiling questoin

[tcross]

a little background... I have a home made arch set up. I had a 4'x4' syrup pan and made an arch to fit under it. I have air under fire, a copper preheater and a hood (last 3 channels). I get around 25 +/- gph when up and running. I run my pan so the channels go right to left on the evaporator with about 3/4" of sap in it. I have a very hard time making light syrup. actually I've never made fancy/golden delicate and have only made a few quarts of amber rich. pretty much all i make is dark robust. I have a 3'x3' sheet of stainless steel kicking around and was wondering if I made one partition for my front channel and one for the second channel if it would help me make lighter syrup? I'm wondering if there could be too much mixing within each channel with such a small set up? i tend to draw off about a quart to a 1/2 gallon each draw. I boil the day the sap comes in and I have all stainless tanks and everything is cleaned after each run. my neighbor has 4k taps right next door to me and he makes plenty of fancy, however all his equipment is state of the art stuff... so I don't think it's my trees/soil rather my set up/process? I prefer darker syrup to lighter syrup, but would like to be able to make some... would my partitions help some, or would they be a waste of time?

[psparr]

You don't say I'm your post how many channels are in the pan now. Sure more channels will help. Also doing a continuous draw will help as well. Will only be a trickle, but your syrup won't be in the pan cooking more. You'll need to be diligent and consistent with defoamer and firing though. What's your sugar content average?

[tcross]

the pan has 4 channels in it. I try to draw as long as possible and it is a trickle about as large as the tip of a pencil lead. after about 20 minutes or so the temp drops and I no longer have syrup. I try to draw it off at the correct density, constantly checking with a hydrometer (usually start just a hair heavy and thin it) I fire the rig consistently. I have a timer set for 5-7 minutes depending on the conditions. defoamer is usually added every other draw or as warranted by the foam. My sugar content is usually right around 2. last year it was higher... closer to a 2.25 average.

[psparr]

1' wide channels are probably the main cause. Lots of sap to boil in each one. Certainly wouldn't hurt to add more dividers.

[Sugarmaker]

Sounds like your doing all the things right!
Are you current partitions fully sealed along the bottom of the pan? Are you preheating and adding the sap at the point farthest away from the draw off point?
your pan may just bee too small to allow a good gradient to be built up. (too much mixing of fresh sap with almost syrup causing darker syrup.
Some pictures may help! I like the fact you have gone to another sugarhouse and recognize the differences in process and equipment. So you could jump in and and spend 10K and get a new big evaporator??? just saying:)
Regards,
Chris

[tcross]

it's a normal 4'x4' syrup pan. off of a 4x12' arch. 4 channels and float box/draw off box on each end. the partitions are fully adhered to the pan. the sap gets preheated (too hot to leave your hand under) and put in the float box (via a float) opposite the draw off box. I've always been under the impression I'm just getting too much mixing. hopefully if I can add two more partitions in the first two channels each it'll help. I'm assuming it can't hurt, so i'll give it a try. my grandfather used to make plenty of fancy syrup on his rig a long time ago. that was a 4x16 or 18 totally flat pan set up... years ago! I've had some inclination to switch the direction of the pan so the partitions run front to back, but I foresee that being worse with the sap heating and cooling as it goes over the fire box and then to the back and so forth? thanks for the replies fellas!

[Sugarmaker]

your sugar content sounds good so you must be on all hard maples? rotating the pan may help? Where are you drawing syrup from the front or the rear of the arch? Have you considered maybe blocking the last partition and putting a big batch of near syrup in there and boiling until complete? Don't add any more just make it 5 inches deep. boil till syrup. Draw it all off and plug the port and start another batch? Not continuous flow but in single batch it might get you lighter syrup?? Also rotating the pan might help with the draw off port at the rear of the arch.
Some pictures might help too.
Maybe trade sap with your neighbor and see if his trees make any better grade?
regards,
Chris

[tcross]

i'll see if I can snap some pictures this weekend. I draw off in the front of the arch, by the firebox. just curious... why would switching the pan direction (drawing off in the rear, farthest away from the firebox) have an affect on the syrup? I'd assume all the switching from cooler to hotter to cooler would create more mixing and longer boil time? could someone explain why/how it would be beneficial?

[Sugarmaker]

I may be missing something here, getting old you know. I believe that the pan your using is a parallel flow syrup pan turned side ways from it normal position to be more lit a cross flow pan? An i think your drawing syrup off near the front of the arch near the fire door? Well in my limited experience. that spot your drawing off may not be the hottest spot on the rig. not sure but it might be the coolest? Just a guess. I have never see many rigs set up that way that work well. also I feel that the syrup is made easier near the hottest part of the arch. in you case this may be the back? near the stack? Not really sure what your firebox looks like? just got a thermal indicator for Christmas and plan to do some checking on my unit and neighbors too.
Will take a look at your pictures when you post them.
regards,
Chris

[Super Sapper]

I think that your channels are too wide for the flow. A 4X12 will have at least 3 times the flow rate with flat pans even more with a flue pan. With the slower flow rate you are doing a lot of mixing in the channels. I would divide all of the channels or at least the last 2 instead of the first 2. Most flue pans are only 2 or 3 channels in a larger size pan than the syrup pan so you could get by with wider channels at the beginning.

[clw]

tcross,

I, too, only make dark syrup. So I will be very interested to see if you find a solution. I have a 2x4 with 3 channels running front to back. I drawoff in the front, but do not have a preheater.

Thanks for asking the question.

[tcross]

i'll take some pictures of my set up and post them over the weekend. i'll be working in the sugarhouse/bush most the weekend anyways. my plan as of now is to add 2 more partitions into each of the first three rows (starting from the fire box moving back) and leave the last one as is and see if that helps... unless someone can convince me otherwise. which I'm all for! I think all the comments are correct about the mixing and that should help somewhat?!

[Sugarmaker]

I am not sure what the smallest / narrowest partition on a arch is? So is there a advantage with small narrow partitions? Just wondering? can syrup get trapped in a hot center channel and not set up the flow gradient?
Are your partitions going to be attached solid along the bottom and ends to avoid mixing? How wide will the new partitions be?
Regards,
Chris

[tcross]

I don't think I'll attach them solidly, so there will still be some mixing. I figure if I attach them solidly and it doesn't work, I'm s.o.l. i'll probably get them as snug as I can and clamp them in place. it won't be perfect but hopefully better than it is. if it works, great, I can try to permanently attach them. if not, I can take them out. I think i'll split the partitions evenly into 3 sections... so they'll be 1'4" x 1' each. I have to re assemble the set up this weekend, so i'll snap some pics and i'll be open to suggestion!

[Super Sapper]

I would run the new partitions parallel with the old ones to make narrower sections instead of going across the channels. The wider your channel the slower it will flow and gives it more time to mix. If you divide each channel in half you will double the speed the sap is in that section thus decreasing the time in section in half. Gradient seems to be pretty consistent (within a couple %) in each channel of a syrup pan but changes from channel to channel so the less you have in the last channel the faster it will get to finished syrup. With the wider sections you have more total volume to get to syrup so it will take longer. I would leave the first 2 channels alone as your flue section and add dividers the long way in the last 2 for your syrup section. Basically making a hybrid flat pan.

[Sugarmaker]

Yea I am not sure about going across the channels?? How was the syrup going to get through the dam?
I assumed that you were doing parallel with the channels like Super mentioned.
regards,
Chris

[tcross]

funny you guys mentioned this over the weekend. I decided to make them parallel to the existing partitions. never got around to making them because everything I did this weekend seemed to have a hiccup here or there. I'm a little concerned about the channels being so narrow, but i'll just have to pay close attention the first few times I boil. here's a picture of my set up... with the hood up. a little crude, but does the trick. 1524815249

[Sugarmaker]

Thanks for the pictures.
I boiled on a antique Warren rig a 3 x 10. We never made any real light syrup. it had 5 flat pans. we boiled in batch mode and made about 4 gallons per batch. It had drop cups in the back pan. These were an attempt to get some hard boiling at the back of the arch. The next pan in front of that was where we made syrup.
Not sure you will get to light syrup with your current set up? You have a good idea for the preheater. do you have a drip tray under it to remove the condesate?
If you had time to do some things you might try this.
Run a line (3/4inch) from the rear draw off box to the front draw off box.
solder in drop tubes in the rear partition bottom to get that sap really boiling.
block off the opening in the rear compartment to the next one. may be able to put a plug in there if it has the round holes.
have a half coupling welded into the second from the rear compartment on the side where the syrup would have to travel the farthest.
This set up would be like the Warren rig, except continuous flow maybe??? Still not sure about making light syrup. Heck that is a challenge in the best year.:)
All that work still may not get you there??
Probably should just poke wood into it and enjoy the dark syrup that you get!
Nice set up by the way!
Regards,
Chris

[tcross]

Thanks Chris! I do have a tray that goes under the preheater... just not in the picture. I also have channels on my hood that catch condensate. I have tinkered with the idea of putting in some drop tubes in the back section of the pan, however I have plans to get myself a 2.5x8 or a 2x10 rig and put cement on the floor in a year or two, so I'm not sure I wanna put all the effort/$ into it. I Enjoy making syrup whatever, color it is, so it's not a huge deal. figured I'd do some tinkering and see if I can improve upon what I already have. i'll find out... hopefully soon! thanks for all the pointers

[Sugarmaker]

Dont give up on the light syrup being a goal. Anyone can make dark syrup. A lot of things have to be right to make light syrup. Your doing fine! Have fun. I have tinkered with my rig almost every year for 20 years. This season not so much:) Your new rig will have a much better chance to make golden delicate syrup, if all the other things fall into place and you stand one one foot and hold your mouth just right too. When it does happen my comment is usually something like: Look at that boys! Now that's dam nice stuff! Then get on with making syrup the best we can.
Regards,
Chris