Building Evaporator Pan

[zburton]

Hi,
I am in the process of building an evaporator, I have almost finished the arch which I am building from a 55 gallon drum and I am trying to design the pan for it. The pan is going to be 30"x22"x8" but what I am not positive on is weather it would be better to build a flat pan or divided pan so this is where everyone on here come in. What would be best for me to do? If the divided pan would be better what type of specifics to building it do I need to know?
Here is a picture of the arch its almost done just few more things to finish.
12439

[optionguru]

Do you plan to batch boil (ie finish to syrup every night) or will you leave partially done (sweet) in the pans and start the next day where you left off? I did a regular flat pan until I got up over 50 taps and then found I didn't have the time or energy to always finish a batch. I then got a divided pan and started drawing off some finished syrup as I went through the day then I would put my partially finished stuff in buckets and kept them in the freezer until I could boil again. I like the divided pans, it's always cool to see and taste the difference from the back to the front.

[zburton]

I'm not quit sure what I am going to do yet honestly. It would be nice to draw off while I cook bit I am not sure if I will have enough trees taped to make it work but at the same time I would hate to build a flat pan when a divided pan would be more efficient. I am hoping to tap more trees in the future so should I build with the plan of expansion or build a flat pan and add dividers later? No matter what I plan on putting a pipe on it with a valve so I can drain the pan easier.

[ericjeeper]

Make sure you go with at the very least a 3/4 inch valve.. One inch is better..

Sent from my XT1254 using Tapatalk

[troynh]

Nice looking build! Just finished my barrel arch a few months ago. I plan on tapping 30-40 trees and went with a 2x3 flat from Smokey Lake. The plan is to batch boil...

-Tim

[zburton]

Thanks it is coming along I have the arch figured out its just the pan I have not figured out yet.

[n8hutch]

Nice looking build! Just finished my barrel arch a few months ago. I plan on tapping 30-40 trees and went with a 2x3 flat from Smokey Lake. The plan is to batch boil...

-Tim
That is A Nice looking Barrel Evaporator you built.

[zandstrafarms]

We did a barrel arch last year.. actually attached two together, with smokestack at end. We used steam table pans for buffet tables bought off Amazon . Allowed 3 pans and a space to warm a stock pot to put near finished sap into. Burn rate 12 gph with no firebricking, outside.
Sold it last fall for $100. Lol.

[Chris Zeger]

Nice looking build! Just finished my barrel arch a few months ago. I plan on tapping 30-40 trees and went with a 2x3 flat from Smokey Lake. The plan is to batch boil...

-Tim

Can you take a picture of the back of your barrel would like to see how you did your stack I'm revamping my barrel stove

[Big_Eddy]

I'm not quit sure what I am going to do yet honestly. It would be nice to draw off while I cook bit I am not sure if I will have enough trees taped to make it work but at the same time I would hate to build a flat pan when a divided pan would be more efficient. I am hoping to tap more trees in the future so should I build with the plan of expansion or build a flat pan and add dividers later? No matter what I plan on putting a pipe on it with a valve so I can drain the pan easier.

Back to the pan.

I want to make one thing clear before anything else. A divided pan is NOT and will never be any more efficient than an undivided flat pan with the same surface area.

That said - The divided pan is more flexible. If you are making the pan yourself, then by all means, install some dividers.

The advantage of a divided pan is that you add raw sap at one end, and because of the dividers, the concentration at the other end of the channels will be greater than at the inlet. The result is that you do not HAVE to boil all your sap all the way to syrup before you can draw off any syrup.

The flip side of the divided pan is that the same gradient makes it more difficult (not impossible) to boil all your sap to syrup, so it is optimized for operations where boils are done daily, and the pans are left full from day to day.

The other critical factor to consider is the size of the pan versus the number of trees tapped. Your pan size is roughly 5 sq ft. By the time you get the whole pan to syrup, you will have boiled off 60+ gallons of sap. If you only have 10 trees, that's a week's sap. If you have 100 trees, that could be a single day.

I recommend a batch boiling process when sap is gathered over several days, then boiled off during one or two long boils each week. (Weekenders). I recommend a continuous flow process if you would typically boil off each day's sap the same day collected.

If you do install dividers but choose to batch boil, just move the sap inlet from end to end during your boil so the density throughout the pan stays about even.

[troynh]

Can you take a picture of the back of your barrel would like to see how you did your stack I'm revamping my barrel stove

Here you go. I used this flue collar: http://www.amazon.com/gp/product/B004V7F99A?psc=1&redirect=true&ref_=oh_aui_detailpage_o07_s00

-Tim

[zburton]

Thanks Big Eddy so for now it would be best to go with a regular flat pan which sounds good to me in the end if I was to decide that having dividers is necessary I could always have them added in. What would be the best thickness of stainless steel to use for the pan? I will probably have it made by someone since I am not that good at welding and do not want to end up with pin holes or something. Also what type of valve would be best to use in the pan for drawing off?

[psparr]

Go as thin as your welder is comfortable welding. The thinner it is the better the heat transfer. Use a stainless ball valve.

[Big_Eddy]

I agree with psparr.
Find a welder is experienced with thin stainless, 20 or 22 gauge is best. 1" stainless half coupling mounted as low as possible on the side of the pan with a stainless ball valve attached.