Appropriate Height for a 4" VM Column

[palinkagus]

Hello gurus of all things column packing related. I am building a 4" VM to make neutral. I would like to know if anyone can calculate the appropriate height of the column, and the appropriate volume of copper SPP required for this build. I tried the calculator on the parent site but I am not confident that the SS scrubbie values are a good match for the substitution of SPP. Here are my parameters:

25 gallon boiler with 5kw, 220v single phase heating element.
Reflux condenser large enough to knock down all vapour at full power.
2" valved takeoff to product condenser.

I'm sorry if I am asking something that has already been covered, but I've searched for the last 5 hours to no avail.

Thanks in advance for your help!

[rad14701]

For a 4" column, 3 - 4 feet of packed column section would be more than enough if using SPP, if it is efficient SPP... Odin might tell you that the height could be half that but I'd rather err on the side of success and also allow for the use of other types of structured packing...

[DAD300]

You wont be able to use wound copper SPP. It gets too heavy and will crush under it's own weight. You could use say 12" on the top or I add 4" of copper mesh at the top of my SS SPP.

My 4" CCVM takes 2 quarts of SPP per foot...a gallon for 24".

I have run it at 24" and 48". 5,500 watts was barely enough with 24" to max the output, but made azeo easily at approx 6 quarts an hour. The production could have been better at 48", but power was an issue. You'll have an advantage with a 25 gallon boiler.

Whatever the parent calculator says for SS Mesh, use approx 1/3 that height for SPP. So if you have 24" of SPP use 72" in the calculator.

Your 2" takeoff is going to make your reflux ratio high...so your takeoff will be less.

Is your SPP scaled for a 4" column?

Look at my sig line for CCVM and SPP notes.

[Bushman]

Odin would be a good reference, I use a 4" but made my own copper scrubbers. When I visited Odin and saw his different sized rigs his SPP for each is sized for the still. I believe he also uses a combination of different packing as DAD suggests.

[palinkagus]

Gentlemen, thank you very much for your responses. I was actually hoping that Odin would weigh in on this topic because it is my intention to purchase the SPP from him. I'm not sure if it's possible but, could the calculator on the parent site be updated to include the proper computations for the various sizes of SPP, and other media as well?

[bearriver]

Odin would weigh in on this topic because it is my intention to purchase the SPP from him.

Odin no longer sells SPP, or anything of use for home distillers except consultations.

There is a product called OS-SPP or oversized spp. It is intended for the iStill 250 units, which are around 5" in diameter. It is also unavailable beyond replacement for iStill owners. It was my intention to purchase some from that source as well when I had the $, but that option has come to a close.

Take Rad's advice. If 4 feet of column height isn't to your liking after running it then look into an optional column extension. 4 inch diameter columns have a great track record with lava rock. The large sum of money you are going to save not buying the spp can be appropriated to adding additional column height, or plates below the packing. Lava rock itself is so cheap it's practically free, and in some cases is. I think Rockchucker got his for free straight from a volcano.