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4" 5 plate output consistency

PostPosted: Fri Jul 16, 2021 5:44 pm
by iOnaBender
Hi ADers,

This post is not pointed towards FSD in anyway, I'm more that happy with their top quality gear, knowledge and after sales support.
Most mention a consistent tooth pick/match stick output stream. I'm having issues where it almost looks like a gentle surge, as in a full stream and then backs off to a broken trickle (see video). Has anyone had a similar experience and if so what was the remedy? I have played around with the copper mesh packing wads (tighter and looser wad) and have not overcome the output stream variation. 500mm packed section consists of (bottom to top) 2 x 500gm rolls (wads) of copper mesh, 4 x copper scrubbers and 1 x half arsed roll of stainless steel mesh. Andrew put me onto too much reflux and water temp for this time of the year in Victoria, dialled back the reflux until gate valve was 1/8 of a turn from being fully closed. Also 2 x 500w aquarium heaters in 1000ltr IBC recirc system to get water temp up to 24degC. This gave me more flow (gate valve around 1/2 a turn from fully closed) but still had the varying output.
I went down the track of thinking the plate in column was the issue, holes too small etc. I then poured 20ltrs of water into it with all the packing as fast as I could and never even sighted the water rise up past any packing, so that removed this from the equation. Any information is appreciated to point me in the right direction.

Output variation
https://kapwi.ng/c/8OZjHBKy

Packed column 1st copper wad
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2nd copper wad
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Copper scrubbers x 4
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Stainless half arsed wad
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Packed column plate
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500mm packed column contents
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Re: 4" 5 plate output consistency

PostPosted: Fri Jul 16, 2021 6:10 pm
by RC Al
That looks perfectly normal, your boiler will have a rolling boil going and the wave action inside will be causing that fluctuation.

I had similar issues, I added boiling chips (couple of handfulls of scoria), but i am direct fired on gas so an easy fix for me, boiling chips arnt quite as suited to elements as they can get caught if you have the multi loop elements and cause them to get too hot in one spot and let the magic smoke out. If you just have the straight barrel element(s) then the chips may work for you.

Re: 4" 5 plate output consistency

PostPosted: Fri Jul 16, 2021 6:20 pm
by RuddyCrazy
Bender with my still running in winter I see water vapour coming off the PC and to get any product out the needle valve is just cracked open and it get it into total reflux only one turn is needed. I do love distilling this time of year so in the morning I'm doing a full boiler of 40$ low wines of my TPW all ready stripped over 4 plates. This is going to be the second strip run then my final spirit run will be over 4 plates and a 500ml packed section and I'll set my still up so it's 2.4 metres high to get that full reflux happening.

I may have to run my BD burner above 4 psi to get some good flow but that end so should bring some good nothing to use for macerations and just see if this years run of TPW make a better nothing.

Edit: Ok looked at that video and mate don't worry it's the outside temp affecting the still and thus the flow rate, I had the same thing happen so i just closed the glass door on my shed and the flow went back to steady.

Re: 4" 5 plate output consistency

PostPosted: Fri Jul 16, 2021 6:22 pm
by RC Al
The chips will also only work if your elemnt is right on the base of the boiler, 3-4 inches above, forget it

Re: 4" 5 plate output consistency

PostPosted: Fri Jul 16, 2021 6:51 pm
by Clickeral
So guys, I never get this issue no matter what external temp I have around me and even running mains water. My stream of output is pretty consistent. Looks like vapour surge to me from the video. Only time I every had output speed go like this was when I flooded my packed section and liquid would go up and out randomly :p

What kind of surge breaks are people running?

Re: 4" 5 plate output consistency

PostPosted: Fri Jul 16, 2021 8:13 pm
by bluc
Is it neutral your running? If so increase power or decrease rc water to get consistant flow :handgestures-thumbupleft:

Re: 4" 5 plate output consistency

PostPosted: Fri Jul 16, 2021 9:17 pm
by RuddyCrazy
When I stripped that first run of my TPW I remember now I had the same thing and just let it go as I was stripping, now with my bubbler as the run goes on after bit of time I ramp up the psi as the plates from the lower one going up stop being loaded, they load up again but I did notice the output was the same going from a toothpick to a splurt then back again. Just put this down to the nature of the still I reckon and don't be too anal about a constant stream.

Re: 4" 5 plate output consistency

PostPosted: Sat Jul 17, 2021 6:05 am
by Wellsy
Good Morning Bender
I suspect it maybe as Bryan suggested mate and outside temp variations as the wind picks up and drops off.
A little breeze can cool the still very quickly. Have you wrapped a towel or something around the still and plates to see if this stabalises things a bit. Not an ideal solution know but it will at least prove a point. If there is no change at all you can be confident temp variations is not the issue and look at flooding or other suggestions.
I have only done 2 runs on my gear mate, ( third will be started in an hour or so ) and had a little bit of variation not as much as you showed, when I left the rear roller door of the shed open.
Good luck and only a few more weeks and the freezing temps will be gone for a year so hang in there mate

Re: 4" 5 plate output consistency

PostPosted: Sat Jul 17, 2021 10:38 am
by Amberale
Something weird going on there I reckon.
What ABV are you getting while that is going on?
I have had unusual output that ended up being flooded packed section.
When it has happened the ABV dropped from my normal 93-94% to around 80% and it started to smell like tails.

Re: 4" 5 plate output consistency

PostPosted: Sat Jul 17, 2021 11:00 am
by Wellsy
I am having a similar issue this today Bender even in the shed.
Not to the same extent as you mate but definitely not steady.
It’s about 3 degrees in the shed mate and my glass tower is clearly showing the plates are not flooded
We will know for sure in a couple of months.

Re: 4" 5 plate output consistency

PostPosted: Sat Jul 17, 2021 11:41 am
by The Stig
iOnaBender wrote: looks like a gentle surge

Im going to say its a combo of 2 things
1 - Inconsistent packing, the 500g rolls are different to the other stainless and copper Its never a good idea to mix packing as they perform differently to each other.

2 - The packing may be too tight in the 500g rolls, I always go heavier and its been pointed out to me that it can cause this issue.

Next run, try running only the 2 rolls of copper mesh but before using it remove say 2 meters from each roll and see if you get a consistent run

Re: 4" 5 plate output consistency

PostPosted: Sat Jul 17, 2021 2:43 pm
by BigRig
I will add the cooling water temp also has a lot to do with it, as much as ambient temp. Too cold and you are shock cooling which will give the surging.

Re: 4" 5 plate output consistency

PostPosted: Sat Jul 17, 2021 2:59 pm
by Amberale
BigRig wrote:I will add the cooling water temp also has a lot to do with it, as much as ambient temp. Too cold and you are shock cooling which will give the surging.


Gotto agree BigRig.
This time of year down here in Vic I only use a tiny trickle through my RC and changed to a needle valve to control it.
The next step was running my second element at approx 50% on top of #1 on full power.
That allows me to run a slightly higher rate of coolant.

That said I couldn’t be stuffed spending the hours down there in this weather.
I need to buy one of those industrial kero space heaters.
There is already an old wood heater down there which is next to useless given the volume of the shed and the huge gaps around the 4-5 metre high roof.

Re: 4" 5 plate output consistency

PostPosted: Sat Jul 17, 2021 6:31 pm
by Wellsy
I reckon you have nailed it big rig

Today’s run was as surging as I have ever known but it was also the coldest the cooling water has ever been

Re: 4" 5 plate output consistency

PostPosted: Mon Jul 19, 2021 8:04 pm
by iOnaBender
Hi Gents,

Thanks for all the info and suggestions.

That looks perfectly normal, your boiler will have a rolling boil going and the wave action inside will be causing that fluctuation.

Ok looked at that video and mate don't worry it's the outside temp affecting the still and thus the flow rate, I had the same thing happen so i just closed the glass door on my shed and the flow went back to steady.

I've insulated boiler with a thermal blanket off of a gas turbine to see if I can control the "waves" and minimise heat loss/cold as a nun's nasty weather affecting boiler externally,
The chips will also only work if your elemnt is right on the base of the boiler, 3-4 inches above, forget it

As you mention elements are too far off bottom of boiler to work effectively.
Is it neutral your running? If so increase power or decrease rc water to get consistant flow

This was a neutral run, I'm still trying to balance power with reflux, I'll get there one day soon hopefully!
Next run, try running only the 2 rolls of copper mesh but before using it remove say 2 meters from each roll and see if you get a consistent run

I've removed around 1mtr off of each wad and completely rerolled them as loose as possible
I will add the cooling water temp also has a lot to do with it, as much as ambient temp. Too cold and you are shock cooling which will give the surging.

I'll fire up the aquarium heaters 2-3 days before next run to see where I end up

Thanks again for all of your wisdom and advice guys

Cheers

Re: 4" 5 plate output consistency

PostPosted: Tue Jul 20, 2021 4:36 pm
by Wellsy
I ran the bubbler again today with a moonshine low wines mix.

Temp in the shed was a warm 10 degrees and cooling water was around 10 - 12 degrees. So everything was about 5 - 6 degrees warmer than when I was running the bubbler on Saturday and the output was a nice consistent stream.

Out put abv was steady 90 - 85 not allowing for temp adjustment until it fell away at the end.

Re: 4" 5 plate output consistency

PostPosted: Tue Jul 20, 2021 7:16 pm
by iOnaBender
Wellsy,

Thanks for the feedback, I'll kick the aquarium heaters in Wednesday/Thursday night. Pot stilling Gin maceration on Friday, WBAB 5 plate Saturday (rehashed packing) and gen 3 CFW 4 plate on Sunday so plenty of run time to see if I can get it dialed in a bit better! :handgestures-thumbupleft:

Cheers

Re: 4" 5 plate output consistency

PostPosted: Tue Jul 20, 2021 7:23 pm
by Wellsy
Yep , today was only my fourth run on the bubbler and all have been a little different.

Still coming to terms with the variations, temp differences definitely has a much bigger impact than it did on the pot still.

Having said that the output is equally different and reflects the effort it takes to get the output




takes

Re: 4" 5 plate output consistency

PostPosted: Sat Jul 24, 2021 5:27 pm
by iOnaBender
Todays run!

Got rid of the broken trickle above 2.1ltr/hr, anything under that it spurts a stream then backs off to a broken trickle again. I ran a WBAB at 2ltr/hr after clowning around to see were flow went to broken trickled. Happier with this run but would still like output to stabilize a bit more.

Cooling water 23degC which allowed more flow through RC
Repacked media in 500mm column as per recommendations
Wrapped boiler in thermal blanket to overcome any ambient temp drafts in shed (need to customise for better/tighter fit)

However when I turned elements off and opened boiler to breathe an extra 200ml ++ landed in cut jug and covered output collection area! Needed a big arse bucket to catch all that shit! :angry-banghead:
Possible vapour/liquid lock within still setup? is this normal? who knows....... :angry-banghead:

cheers

Re: 4" 5 plate output consistency

PostPosted: Sat Jul 24, 2021 8:05 pm
by Wellsy
Every run you become more predictable mate.

Then of course you will change washes and it all changes again lol