Combining different random packings (SPP and Pall Rings)

[lurklaban]

Hi all!

Starting a new thread here...

I'm step by step trying to produce SPP but it takes a while by hand and the cost for wire is not insignificant... While I'm working up the volume of SPP I'm combining the SPP with the Pall Rings that was there before but the question of how to do that has arisen...

My intuitive thought was that since the SPP is better in separation it should be on top of the Pall Rings to do the fine tuning work, however they are easily mixed when emptying and refilling the column between runs (and tedious to separate) and my impression, though it's not established, is that the results have been better the next run when they have mixed, though it's really hard to tell since there are so many parameters and the difference in results are so small. However, I have read that SPP works best in a semi flooded state and though I'm not really sure what that meens I guess the flooding starts from the bottom of the column and rises higher and higher the more power that is supplied which would make the Pall Rings compleatly drowned to achieve a semi flooded state at the upper part of the column for the SPP and I'm not sure how that effects the Pall Rings...? Or am I thinking backwards?

Asking google AI (I haven't been able to find any info on this on the web) it gave me different answers depending on how I formulated the question - SPP over Pall Rings and Pall Rings over SPP depending on formulation. Now lately when I've asked it seems to have settled to the opinion that they should not be mixed and if combined they should be separated in different sections with the SPP on top. Dont know if its the AI that has changed/learned more or if it's my formulation of the question)

I'm leaning towards doing the tedious work of separating them for this run and using a scrubber to separate them... AI, however, does not recommend scrubbers for separation caus of chaneling and instead recommend a dish of mesh, which I'm not sure how to accomplish... when it comes to the scrubber I'm most worried that it will compress too much by the weight from the SPP so that it will make too much vapor resistance...

Another consern, should there be a distance betwen the separator and the section of Pall Rings beneath?

Alot of questions and alot of text - hopes someone makes it through it : )
Any input is greatly appreciated!

Cheers and all the best!
Lurk

[Salt Must Flow]

I would separate the two using a roll of copper mesh (which is approx 5" tall). Copper mesh will separate them. It will NOT crush. It will not cause restriction like a mesh screen and the junction will not cause flooding. Using a roll of copper mesh will make it easier to separate the two types of packing without allowing them to become mixed.

I'd put SPP on top and the rings below. Just don't roll the copper mesh real tight and you don't have to make it really loose either. Just gently start rolling it and it will work out just fine.

Right now I'm doing something somewhat similar. I have 7' of 4" column. I'm using 1/2" ceramic rings on the bottom 3' and the top 4' contains the same ceramic rings, but they're split in half like shown below.

Split Ceramic Ring Packing 01.jpg

At the base of each section of column I soldered a copper cross using copper wire.

Packing Retainer 02.jpg

I use this thin roll of mesh over top of each copper cross to support the packing within the column above. This has worked great with supporting Lava Rock and now using ceramic rings.

Copper Mesh Short Roll.jpg

[lurklaban]

Thank you @"Salt Must Flow"! I should have listened to your advice, but I was in a hurry and didn't have access to copper mesh and I realized that we're already using a scrubber at the bottom to make the smaller SPP not falling through the main screen at the bottom so I thought that if that can hold both Pall Rings and SPP, another one between the two will not cause any problems... I was wrong... as soon as the boiler reached boiling point the whole rig started shaking and actually I was abit worried that the whole thing would blow both me and the house to pieces, so I had to reduce the power quite a bit. It's in full reflux mode now but I will take it down and remove the scrubber... darn...

What do you think of this
https://www.clasohlson.com/se/Sil-Coline/p/34-5114

to cut out a disc and maybe weld a stabilizing wire around it (eeeh, I realy can't weld verry good though and the mesh is really thin...) and then maybe a S-shaped spring to hold it in place 2 cm above the Pall Rings (can't weld or solder inside the column and need to bee flexible with the possition - it's what's currently holding everything at the bottom)? Eeeh, the copper mesh might be easier, but I don't really like copper since we've had quite a lot of problems with blue and yellow spirits...

[Salt Must Flow]

Thank you @"Salt Must Flow"! I should have listened to your advice, but I was in a hurry and didn't have access to copper mesh and I realized that we're already using a scrubber at the bottom to make the smaller SPP not falling through the main screen at the bottom so I thought that if that can hold both Pall Rings and SPP, another one between the two will not cause any problems... I was wrong... as soon as the boiler reached boiling point the whole rig started shaking and actually I was abit worried that the whole thing would blow both me and the house to pieces, so I had to reduce the power quite a bit. It's in full reflux mode now but I will take it down and remove the scrubber... darn...

What do you think of this
https://www.clasohlson.com/se/Sil-Coline/p/34-5114

to cut out a disc and maybe weld a stabilizing wire around it (eeeh, I realy can't weld verry good though and the mesh is really thin...) and then maybe a S-shaped spring to hold it in place 2 cm above the Pall Rings (can't weld or solder inside the column and need to bee flexible with the possition - it's what's currently holding everything at the bottom)? Eeeh, the copper mesh might be easier, but I don't really like copper since we've had quite a lot of problems with blue and yellow spirits...

When I click on the link all I see is this:

Site.jpg

[lurklaban]

It's not just that you have to make your cookie choice...? The button to the right says "refuse all" ...