• Advertisement

Automated LM Build

These usually have the means for returning the spirits to the column and usually allow metering of the take off to help in the reflux.

Re: Automated LM Build

Postby manofconstantsorrow » Sat Sep 20, 2014 5:37 pm

Landru,
Any new updates on your progress?

MOCS
The day you quit learning is the day you start dying!
"I am an incurable gadgeteer, and I like enormously to set up a theory and then track down the consequences" Murray Leinster
http://www.youtube.com/watch?v=08e9k-c91E8
User avatar
manofconstantsorrow
 
Posts: 67
Joined: Sun Aug 25, 2013 10:21 pm
Location: Minnesnowda
Equipment type: A work bench full of parts waiting to be assembled

Re: Automated LM Build

Postby Landru » Mon Sep 22, 2014 7:29 pm

Still kicking. Waiting on welding and some free time to finish assembling the controller. Nothing too noteworthy to share via pictures quite yet.
Landru
 
Posts: 20
Joined: Tue Jun 17, 2014 2:46 pm

Re: Automated LM Build

Postby Landru » Sun Jan 28, 2018 1:44 am

A few years and a few kids later I finally have this thing running in semi-automatic mode.

Upgrading to the latest and greatest in simpler electronics technology, I re purposed a RAMPS 1.4 3D printer controller which already had an LCD, Click Encoder, beeper, SD Card Reader, stepper motor driver, and mosfet outputs.

Currently control the takeoff valve with a Stepper motor for precise control. Since doing my first few runs I realize there is some backlash in the valve mechanism, so I always turn the valve back to 0 before opening the valve to the new reading.

Additionally, the valve flow rate increases as the body heats up. once up to temperature after few minutes of running, this is no problem. I'm not sure how to deal with it during the initial warm up phase yet, though. It can make a flow rate difference of over 100%. I'm starting to think I should look for a purpose made stepper valve. This appears to be the weakest link so far.

Temperature reading with the ds18b20 sensors has been phenomenal, and exceeded all expectations. I'm able to get 0.06C precision on the readings with no random fluctuations. The actual accuracy may not be perfect, but I only need precise relative changes to know whats going on.

I did get two different temperature reading for Azeo, both very stable on their respective runs. I did change the height of SPP in the column by a few inches, which may be to blame. Will try and narrow this down on future runs, whether it is from the still configuration or some long term calibration issue with the sensor.

All data is logged to the SD card in 15s intervals, and a new file is created for every power up so as not to overwrite old data.

LM Column
2" Diameter Tricolver
15Gallon Keg
35" SPP from Stainlessstuff.net

For a 10 Gallon, 20% charge:

- Fores Max Power 2.2 kW with full reflux
- Hearts Collection at 2.8 kW, 3 L/h @Azeo.
-Anything over 2.8 kW while taking hearts starts to flood the column as visible through the top sight glass.

It's possible I could increase the power if I also increased the takeoff rate. Perhaps next run I'll give it a try.
Landru
 
Posts: 20
Joined: Tue Jun 17, 2014 2:46 pm

Re: Automated LM Build

Postby minime » Tue Jan 30, 2018 3:38 pm

Landru wrote:Additionally, the valve flow rate increases as the body heats up. once up to temperature after few minutes of running, this is no problem. I'm not sure how to deal with it during the initial warm up phase yet, though. It can make a flow rate difference of over 100%. I'm starting to think I should look for a purpose made stepper valve. This appears to be the weakest link so far.
I'm really interested to see if you can get some consistency. That's why most are running VM because they are so forgiving.
Landru wrote:Anything over 2.8 kW while taking hearts starts to flood the column as visible through the top sight glass.

Actually you should try to run with your SPP in a semi flooded state. That's where you'll get the best HETP

this is an interesting video https://youtu.be/mJtNrnflY0s
Never save the best for last!
User avatar
minime
 
Posts: 4033
Joined: Tue Dec 09, 2008 10:47 am
Location: Gr8WhiteNorth
Equipment type: VM enthusiast.

Re: Automated LM Build

Postby minime » Tue Jan 30, 2018 3:40 pm

Landru wrote:Additionally, the valve flow rate increases as the body heats up. once up to temperature after few minutes of running, this is no problem. I'm not sure how to deal with it during the initial warm up phase yet, though. It can make a flow rate difference of over 100%. I'm starting to think I should look for a purpose made stepper valve. This appears to be the weakest link so far.

I'm really interested to see if you can get some consistency. That's why most are running VM because they are so forgiving.

Landru wrote:Anything over 2.8 kW while taking hearts starts to flood the column as visible through the top sight glass.

Actually you should try to run with your SPP in a semi flooded state. That's where you'll get the best HETP

this is an interesting video https://youtu.be/mJtNrnflY0s
Never save the best for last!
User avatar
minime
 
Posts: 4033
Joined: Tue Dec 09, 2008 10:47 am
Location: Gr8WhiteNorth
Equipment type: VM enthusiast.

Re: Automated LM Build

Postby Landru » Fri Feb 02, 2018 11:37 pm

minime wrote:Actually you should try to run with your SPP in a semi flooded state. That's where you'll get the best HETP


Any advice for maintaining a semi flooded state?

As soon as I start getting any bubbling liquid visible, it quickly progresses to full flooding and only gets worse with time.

The ID of the glass itself is ~2mm larger then the rest of the column, and the bubbling always seems to start at the base of the glass.
It is possible it starts lower in the column where I cant see.

2800W, no liquid at all
2900W - https://imgur.com/5bsjDcE
2900W after a few minutes - https://imgur.com/OKGE9ba
Landru
 
Posts: 20
Joined: Tue Jun 17, 2014 2:46 pm

Re: Automated LM Build

Postby minime » Sat Feb 03, 2018 6:52 am

Landru wrote:The ID of the glass itself is ~2mm larger then the rest of the column, and the bubbling always seems to start at the base of the glass. It is possible it starts lower in the column where I cant see.


From my experience the flooding begins in the lowest part of the packing because that's where the liquid is at the lowest proof. I'm not sure what your top condenser area looks like but I can actually hear my column starting to gurgle listening at the reflux condenser. I cut back input until the noise is almost gone and it's good 'till near the end of the run when most of the reflux has to be returned to the column to maintain purity. I don't mess with tails and just run 'em out full tilt from that point.

thanks for the video, that was helpful ......doesn't look like you're flooded in the sight glass so likely the problem is lower in the column. If you could maintain that activity just barely above the SPP I would think that's pretty close to where you'd want to be. Hopefully you can find your happy place :lol:

Cheers
Never save the best for last!
User avatar
minime
 
Posts: 4033
Joined: Tue Dec 09, 2008 10:47 am
Location: Gr8WhiteNorth
Equipment type: VM enthusiast.

Re: Automated LM Build

Postby Landru » Wed Feb 07, 2018 12:52 am

Any data on how the flooding point is altered by reflux temperature?

I would assume colder reflux leads to flooding sooner, as it takes longer for the reflux to vaporize again and therefore more of it flows through the top sections of SPP.
Landru
 
Posts: 20
Joined: Tue Jun 17, 2014 2:46 pm

Re: Automated LM Build

Postby minime » Fri Feb 09, 2018 9:57 pm

Landru wrote:I would assume colder reflux leads to flooding sooner, as it takes longer for the reflux to vaporize again and therefore more of it flows through the top sections of SPP.

Easy to think that but it doesn't really work that way. It's a combination of reflux temperature and power input and it quickly finds a balance or you get into trouble.
Next time you run stabilize your column and play with water input volume and you'll see it doesn't affect much at all. Common sense tells us to run the water temperature just cool enough to get the job done (condense all the vapour) No point in using more water than we need right?
Never save the best for last!
User avatar
minime
 
Posts: 4033
Joined: Tue Dec 09, 2008 10:47 am
Location: Gr8WhiteNorth
Equipment type: VM enthusiast.

Re: Automated LM Build

Postby Suzukidave » Sun Feb 11, 2018 8:25 pm

IMG_0615.JPG
At what point is the column thought of as flooded ? I often have at least 1 plate with action like in Landru's second video but doesnt advance up the column any further than the video shows so i was thinking that that was good plate action ?
User avatar
Suzukidave
 
Posts: 43
Joined: Fri Jan 12, 2018 3:59 am

Re: Automated LM Build

Postby minime » Mon Feb 12, 2018 1:02 pm

Suzukidave wrote:At what point is the column thought of as flooded

I have allowed my packing to become flooded to the point that liquid spews out the top of the column. It's a scary situation to say the least but that was part of the learning curve with SPP. Can't remember ever being flooded with scrubbers......
Anyway for me I really have no interest in automation as I'd never leave my equipment running unattended and I find it quite easy to maintain purity (or close to for rum) with my VM column. You photo appears to show fairly violent action on that plate. (not sure if it's bubble caps or not) but that's some serious activity.
I no longer use any kind of plate because I find the SPP is adequate on it's own. I'm distilling with temperature probes at the top and bottom of the column and I do try to get just enough flooding to hear it gurgling slightly at the reflux condenser.
Don't know if that was any help at all :?
Never save the best for last!
User avatar
minime
 
Posts: 4033
Joined: Tue Dec 09, 2008 10:47 am
Location: Gr8WhiteNorth
Equipment type: VM enthusiast.

Previous

Return to Packed Columns

Who is online

Users browsing this forum: No registered users and 3 guests

cron