Evaporator Build Questions

[maple flats]

Tucker, I moved the post to Homemade. If you use ceramic blanket with wood fired, use it on all except the grates and the air inlets. For nozzles, I used 1/4" black pipe and welded them in on the desired angle, spaced every 6" and have them 6" below the pan. Originally I thought I'd just let the intense heat "prune" the length of the nozzles, which stick out from 1" to 2" out of the refractory cement. They still look like new after over 10 seasons to my surprise. . If you want to use your square tube as your top, you will need to extend the nozzles to get then 6" below the pan and then angle them down towards to opposite edge of the grate.
At a 2x4 pan size you could use a 7" or and 8" stack. Be sure to design it to draw across the entire width, not just 7 or 8". High pressure AOF is high pressure, not high volume. If your AUF will run off the same HP blower, it's still low volume.
The ramp helps push the heat up to the pan, leave enough space for drop flues in case you ever want to get a drop flue pan, and leave 2-3" additional under that. So if you got 7" drop flues you want about 10" space under it. Fill that space with vermiculite or rock wool, and top it with fire brick to hold the vermiculite in place.
Have fun most of all.

[Tuckeradams2012]

I have attached the original post below for reference.

Afternoon All,

Figured I would finally get my mind off of the election and back to maple. I have a couple quick questions as I will be building my oil evaporator over the next few weekends. I will be putting a 2x4 pan on top, AOF using square tubing, AUF piped from the same blower and plan on exiting with a smoke stack out of the top and not the side.

Question 1: When it comes to ceramic blankets should it wrap the entire bottom of the fire box which will have grates and AUF on top of it? AUF most likely will be using black iron pipe like others I have seen on here. Also should the firebox be 24" with firebrick or without firebrick installed?

Question 2: What do folks use for the nozzles for square tubing for AUF, and how do they bend them down? Theoretically can I use the Square tubing as my lip for the pan or should I still utilize angle iron? or should it sit lower in the fire? I am very new to welding, so should be interesting.

Question 3: Is the ramp necessary or can we just call it 2" flat under the pan and insulate with sand or leftover firebrick, maybe more blanket??

Question 4: Stack size. After doing research on here I haven't come to a conclusion about stack size as it pertains to AOF/AUF. Currently have a barrel stove door/stack set that is 6", just need to know if I need to go to 8" or not.

Thanks for all your help. Almost ready for the action!

[Tuckeradams2012]

Tucker, I moved the post to Homemade. If you use ceramic blanket with wood fired, use it on all except the grates and the air inlets. For nozzles, I used 1/4" black pipe and welded them in on the desired angle, spaced every 6" and have them 6" below the pan. Originally I thought I'd just let the intense heat "prune" the length of the nozzles, which stick out from 1" to 2" out of the refractory cement. They still look like new after over 10 seasons to my surprise. . If you want to use your square tube as your top, you will need to extend the nozzles to get then 6" below the pan and then angle them down towards to opposite edge of the grate.
At a 2x4 pan size you could use a 7" or and 8" stack. Be sure to design it to draw across the entire width, not just 7 or 8". High pressure AOF is high pressure, not high volume. If your AUF will run off the same HP blower, it's still low volume.
The ramp helps push the heat up to the pan, leave enough space for drop flues in case you ever want to get a drop flue pan, and leave 2-3" additional under that. So if you got 7" drop flues you want about 10" space under it. Fill that space with vermiculite or rock wool, and top it with fire brick to hold the vermiculite in place.
Have fun most of all.


Thanks Dave you are a Rockstar for moving the thread, as a millennial I should have figured it out on my own on how to move it.

Would you still use square tubing if mounted below the topline? and if so is 2" the best way to go anyways? It is good to know to angle them towards the opposite side of the grate so thanks for that.

Luckily already have a cool bouncy house blower that I purchased from FB Marketplace for cheap that is HP. So your suggestion would be get an additional blower for the AUF on top of the AOF and not pipe together?

My design does incorporate the standard oil drum across width to collect all the heat rather than having cold spots, creates the base stack effect like on the big evaporators. No drop flues for me in the future, I don't have the tap count to warrant it, and I'll buy a bucket RO first before that if I feel the need to decrease boiling time.