Theoretical knockdown power of shotgun condensers

[rockymars]

Hi,

My new 2” CM rig (bought off AliExpress) features a 5 tube x 200mm shottie RC, and a 5 x 400mm shottie PC, all stainless. Internal pipes are 8mm ID.

CM still

While I’m waiting for more parts to arrive, I’m curious as to what the theoretical knockdown limits of the condensers might be.

For stripping in pot still mode, I can throw up to 2400W at the PC. For spirit runs I will use max 1300-1400W, to stay below the recommended vapour speed of 20ft/s.

The calculator on the main page was presumably written for copper, using a heat transfer coefficient of 850W/m2C. I’ve played around with it, but it looks like the PC wouldn’t stand up to 2400W, even if it were copper.

What would be an appropriate heat transfer coefficient be for stainless steel?
Can the 200mm RC knock down everything thrown at it at 1400W for full reflux?
Can the 400mm PC cope with 2400W during stripping runs?

[Sporacle]

It's a bit simplistic but the PC will knock down what it knocks down I have no experience with SS, theoretically you have 600mm of PC for stripping runs if you connect the RC to your PC in pot mode if you know what I mean

[rockymars]

theoretically you have 600mm of PC for stripping runs if you connect the RC to your PC in pot mode if you know what I mean

Hey Sporacle, thanks for the reply. Being a fully modular tri clamp rig, it’s not only a theoretical possibility but very much a great, doable idea! Who says I must put the bits where the picture shows??

[Salt Must Flow]

A 400 mm shotgun condenser (15.7" long) is a bit shorter than what I'd prefer even if it were copper, but it will probably work just fine with the power you will be running. I made mine 24" long and it works flawlessly knocking down 5500W as well as 11000W (with higher water flow rate). So for the power you're using it should work just fine. Worst case ... you just have to run water at a higher flow rate than if it were longer.

I always feed each condenser with their own feed lines as well as exit lines.

[rockymars]

A 400 mm shotgun condenser (15.7" long) is a bit shorter than what I'd prefer even if it were copper, but it will probably work just fine with the power you will be running. I made mine 24" long and it works flawlessly knocking down 5500W as well as 1100W (with higher water flow rate). So for the power you're using it should work just fine. Worst case ... you just have to run water at a higher flow rate than if it were longer.

I thought a higher flow rate might work, I’ll test it when I’m doing my water cleaning run. Would give me the actual upper limit anyway, and the required flow rate. The tubing is 1/4” ID PVC air hose, I might have to upgrade that.

I always feed each condenser with their own feed lines as well as exit lines.

Yeah I was going to do split my water lines, ball valve on the PC with bleed off for excess water (to extend the life of my pump). The RC will have a needle valve, also with a bleed off.

[howie]

i only use my 200mm shotty on reflux runs (neutral & holding rum spirit runs) as a RC.
so the power is usually only 1200w-1500w, which the 200mm shotty handles with no problem.
i think i remember, in the early days, accidentally having the full 2400w on and it couldn't hold that
i'm not sure how you would calculate the holding power of a shotty.
mine has 8 x tubes & 5 spacers, which (apparently) makes it quite efficient.
i've seen loads of shottys with less tubes and spacers, so the efficiency equation would be complicated by the different builds.

nothing gets past the 400mm shotty, even at 2400w. (used as PC only)

[Yummyrum]

i only use my 200mm shotty on reflux runs (neutral & holding rum spirit runs)
so the power is usually only 1200w-1500w, which the 200mm shotty handles with no problem.
i think i remember, in the early days, accidentally having the full 2400w on and it couldn't hold that
i'm not sure how you would calculate the holding power of a shotty.
mine has 8 x tubes & 5 spacers, which (apparently) makes it quite efficient.
i've seen loads of shottys with less tubes and spacers, so the efficiency equation would be complicated by the different builds.

nothing gets past the 400mm shotty, even at 2400w.

Howie, for the sake of clarity , I'm guessing when you talk about your shotty's here , both the 200mm and the 400mm , you are using them as Deflagmators ( partial condensers) in CM still head and their ability to hold full (100%) reflux .

[howie]

i only use my 200mm shotty on reflux runs (neutral & holding rum spirit runs)
so the power is usually only 1200w-1500w, which the 200mm shotty handles with no problem.
i think i remember, in the early days, accidentally having the full 2400w on and it couldn't hold that
i'm not sure how you would calculate the holding power of a shotty.
mine has 8 x tubes & 5 spacers, which (apparently) makes it quite efficient.
i've seen loads of shottys with less tubes and spacers, so the efficiency equation would be complicated by the different builds.

nothing gets past the 400mm shotty, even at 2400w.

Howie, for the sake of clarity , I'm guessing when you talk about your shotty's here , both the 200mm and the 400mm , you are using them as Deflagmators ( partial condensers) in CM still head and their ability to hold full (100%) reflux .

sorry, for clarity.....
the 200mm is used as a RC only
the 400mm is used as a PC only
in a 2" CM still, as per rockymars purchase/picture

orginal post edited, we need a proof reader sometimes

[Stilljoy McFlavour]

Edited for misreading the OP
Wrote I had the same set, but both my condensers were 8 x 8 mm. They have no issues with whatever I throw at them; which is 3.5 kW at the moment.

[rockymars]

i only use my 200mm shotty on reflux runs (neutral & holding rum spirit runs) as a RC.
so the power is usually only 1200w-1500w, which the 200mm shotty handles with no problem.
.
.
.
nothing gets past the 400mm shotty, even at 2400w. (used as PC only)

According to the calculator, to keep my vapour speed at or under 20 ft/s on the 2” column, I need to limit heat input to 1,373W. Your experience gives me hope that the 200mm *might* keep up, as my worry is that the condensers might be the limiting factor in achieving reasonable production rates.

i'm not sure how you would calculate the holding power of a shotty.
mine has 8 x tubes & 5 spacers, which (apparently) makes it quite efficient.
i've seen loads of shottys with less tubes and spacers, so the efficiency equation would be complicated by the different builds.

I scoured the internet today for write ups on jacket type condeno, and how to calculate their knockdown power. I think I found some valuable stuff, and will take the next few days to work through that.

Efficiency improvements like baffles etc. make the calculations tricky, and would need finite element analyses to get very accurate results. That way out there, I don’t have the appetite to learn that!
I would be more than happy with the conservative results a simplified calculation would yield, it will be conservative and good enough for my purposes!

[rockymars]

sorry, for clarity.....
the 200mm is used as a RC only
the 400mm is used as a PC only
in a 2" CM still, as per rockymars purchase/picture

@howie do you have any pictures of, or perhaps a link to, your setup? I’m quite curious.

[rockymars]

Edited for misreading the OP
Wrote I had the same set, but both my condensers were 8 x 8 mm. They have no issues with whatever I throw at them; which is 3.5 kW at the moment.

Hey @stilljoy, thanks for joining the thread! Are your condensers all stainless, or copper?

If one assumes (simplistically) that my 5 tubes have the equivalent of 5/8=62.5% the knockdown power of yours, I might be able to throw about 2.2kW at mine. I’ll take that!

[EricTheRed]

My 60cm ss shotgun knocks down 3kw with a trickle of water.
You'll be fine with just a bit higher flow

[rockymars]

Someone reported in another thread that he cold hold full reflux on the same still:
https://homedistiller.org/forum/viewto ... 7#p7604937
I’m not sure what his production rate was though, but what does matter is that I’ll have a working still that does produce a good neutral. How fast, well I’ll find that out, won’t I?

[rockymars]

My 60cm ss shotgun knocks down 3kw with a trickle of water.
You'll be fine with just a bit higher flow

Hey @ericthered,
Thanks for the contribution! What are the attributes of your shotty (OD, number of pipes and ID, copper/ss etc.)?

[howie]

i only use my 200mm shotty on reflux runs (neutral & holding rum spirit runs) as a RC.
so the power is usually only 1200w-1500w, which the 200mm shotty handles with no problem.
.
.
.
nothing gets past the 400mm shotty, even at 2400w. (used as PC only)

According to the calculator, to keep my vapour speed at or under 20 ft/s on the 2” column, I need to limit heat input to 1,373W. Your experience gives me hope that the 200mm *might* keep up, as my worry is that the condensers might be the limiting factor in achieving reasonable production rates.
imho i think you're overthinking and maybe interpreting things wrong.
a 2" CM usually produces good quality product at 1.2-1.5l per hour (drip drip dribble) on a reflux spirit run, any faster and you're probably smearing.
you will smear if your power is too high, so you only set your power to get a suitable output, not the other way around.
so i keep to the famous drip-drip dribble on neutral runs, the 200m shotty will be fine.

i'm not sure how you would calculate the holding power of a shotty.
mine has 8 x tubes & 5 spacers, which (apparently) makes it quite efficient.
i've seen loads of shottys with less tubes and spacers, so the efficiency equation would be complicated by the different builds.

I scoured the internet today for write ups on jacket type condeno, and how to calculate their knockdown power. I think I found some valuable stuff, and will take the next few days to work through that.
i don't think you can compare jacket type condensers to shottys.
dont' worry too much, do a FFV or TPW and have a play with some low wines.

Efficiency improvements like baffles etc. make the calculations tricky, and would need finite element analyses to get very accurate results. That way out there, I don’t have the appetite to learn that!
I would be more than happy with the conservative results a simplified calculation would yield, it will be conservative and good enough for my purposes!

[howie]

[/quote]
@howie do you have any pictures of, or perhaps a link to, your setup? I’m quite curious.
[/quote]
i started off with almost exactly the same as you, then added another 600mm(?) column to make it 1100mm.
a parrot came next, clark rubber pipe insulation on columns, full packing, rewired elements + power controller, gate valves on water inlet.
this pic is about 1 year old.
boiler now has a jacket
water inlets have 90degree bends so the hoses don't kink.
silicone hose is gone
i think the shottys make the CM a good unit, it's just that the 2" is slow (but so am i )
my first reflux runs with the original set up like yours, i could only get 89abv and i wasn't impressed with the taste.
now i can get 96abv and good clean hearts.

[Stilljoy McFlavour]

Edited for misreading the OP
Wrote I had the same set, but both my condensers were 8 x 8 mm. They have no issues with whatever I throw at them; which is 3.5 kW at the moment.

Hey @stilljoy, thanks for joining the thread! Are your condensers all stainless, or copper?

If one assumes (simplistically) that my 5 tubes have the equivalent of 5/8=62.5% the knockdown power of yours, I might be able to throw about 2.2kW at mine. I’ll take that!

Indeed, both defleg and PC are stainless. Same lenght also; 20 and 40 cm. The deflag effortless maintains full reflux at 3.5 kW at water temp ~13 deg C. I would think your calculation is good enough for the purpose.

[EricTheRed]

My 60cm ss shotgun knocks down 3kw with a trickle of water.
You'll be fine with just a bit higher flow

Hey @ericthered,
Thanks for the contribution! What are the attributes of your shotty (OD, number of pipes and ID, copper/ss etc.)?

[rockymars]

imho i think you're overthinking and maybe interpreting things wrong.
a 2" CM usually produces good quality product at 1.2-1.5l per hour (drip drip dribble) on a reflux spirit run, any faster and you're probably smearing.
you will smear if your power is too high, so you only set your power to get a suitable output, not the other way around.
so i keep to the famous drip-drip dribble on neutral runs, the 200m shotty will be fine.

Overthinking?? Me??
The purpose of the OP was to see if anyone has done some form of calc on shotties. I wanted to know their theoretical upper limits. But I’m aware that blasting the boiler could cause smearing. I’ve been reading posts by a gentleman named “charcoal” (who has/had the same rig), amazing how much you can learn from those that refuse to listen…

i don't think you can compare jacket type condensers to shottys.
dont' worry too much, do a FFV or TPW and have a play with some low wines.

Ok, hang on
FFW… first water run?
TPW…?

Yeah I’ve decided overnight to just wait for my extra bits to arrive and then I can experiment to hearts content. I’m bloody ITCHING!!!

[rockymars]

@howie, mate, now you have me drooling! Your setup is looking good!

i started off with almost exactly the same as you, then added another 600mm(?) column to make it 1100mm.
a parrot came next, clark rubber pipe insulation on columns, full packing, rewired elements + power controller, gate valves on water inlet.
this pic is about 1 year old.
boiler now has a jacket
water inlets have 90degree bends so the hoses don't kink.
silicone hose is gone

I ordered the extra 24” spool and all the other bits you mention. I’ll do the insulation as per your recommendation in another thread. I’m keen to do a “out of the box” run first, and then do a comparison with all the upgrades.

Did yours also have the air hoses and cheap, fiddly valves for cooling water control? How much water do you push through the condensers?

i think the shottys make the CM a good unit, it's just that the 2" is slow (but so am i )
my first reflux runs with the original set up like yours, i could only get 89abv and i wasn't impressed with the taste.
now i can get 96abv and good clean hearts.

That’s what I needed to see! Now I feel completely validated in buying this kit.

[rockymars]

Indeed, both defleg and PC are stainless. Same lenght also; 20 and 40 cm. The deflag effortless maintains full reflux at 3.5 kW at water temp ~13 deg C. I would think your calculation is good enough for the purpose.

Aah, thanks for confirming. What sort of water flow rates are you pushing through the condensers?

[rockymars]

Hey @ericthered,

Yours are better quality than mine…

I was wanting to build up a kit from better quality parts, but it would have cost me ~40% more, so I bought the premade kit instead. But heck if it works, that’s all that matters isn’t it?

@howie’s input gives me plenty piece of mind that this kit, slightly upgraded, will do what I want it to do.

I was thinking of building a dedicated stripping unit (I’m concerned about tarnishing the rig with flavoured spirits), and at that time I might buy some better quality parts for the neutrals still and retire esp. the shotties for service on the stripping still. Heck I could hook up the two shotguns in series to get a 5 tube x 600mm PC, as somebody suggested earlier. That would be a beast.

I love tri clamp, it’s like playing with Lego again!

[Salt Must Flow]

imho i think you're overthinking and maybe interpreting things wrong.
a 2" CM usually produces good quality product at 1.2-1.5l per hour (drip drip dribble) on a reflux spirit run, any faster and you're probably smearing.
you will smear if your power is too high, so you only set your power to get a suitable output, not the other way around.
so i keep to the famous drip-drip dribble on neutral runs, the 200m shotty will be fine.

Overthinking?? Me??
The purpose of the OP was to see if anyone has done some form of calc on shotties. I wanted to know their theoretical upper limits. But I’m aware that blasting the boiler could cause smearing. I’ve been reading posts by a gentleman named “charcoal” (who has/had the same rig), amazing how much you can learn from those that refuse to listen…

i don't think you can compare jacket type condensers to shottys.
dont' worry too much, do a FFV or TPW and have a play with some low wines.

Ok, hang on
FFW… first water run?
TPW…?

Yeah I’ve decided overnight to just wait for my extra bits to arrive and then I can experiment to hearts content. I’m bloody ITCHING!!!

I don't know what those are, but do a vinegar water run (let vapor just blast straight through the rig). Next do a sugar wash for a sacrificial run. Don't keep anything you collect unless it's for fire starter, solvent, etc... After your cleaning runs you're ready to to do a run you can keep.

[rockymars]

water inlets have 90degree bends so the hoses don't kink.
silicone hose is gone

Can you provide more details on how you connected the hoses to the shotties?

Where did you buy your connectors from? What size and thread are they?

[rockymars]

I don't know what those are, but do a vinegar water run (let vapor just blast straight through the rig). Next do a sugar wash for a sacrificial run. Don't keep anything you collect unless it's for fire starter, solvent, etc... After your cleaning runs you're ready to to do a run you can keep.

Yep definitely going to do the vinegar and sac runs. I have a wash getting ready for the latter.

I have heaps of uses for the output of the sac run, it won’t go to waste.

[Salt Must Flow]

I was thinking of building a dedicated stripping unit (I’m concerned about tarnishing the rig with flavoured spirits), and at that time I might buy some better quality parts for the neutrals still and retire esp. the shotties for service on the stripping still. Heck I could hook up the two shotguns in series to get a 5 tube x 600mm PC, as somebody suggested earlier. That would be a beast.
I love tri clamp, it’s like playing with Lego again!

Don't sweat it at all. It won't funk up your neutral runs at all. That's what's so great about a good reflux column, it cleans that stuff up nicely. I once made a bunch of UJSSM and it sat around for so long, I wasn't drinking it so I just ran it through my VM and it came out amazing. No odor or flavor whatsoever. If it can do that then you can use the same equipement/boiler for both flavored and neutral spirits.

What would be beneficial is a bigger boiler for doing stripping runs. Match your ferments or fermenters size with the stripping boiler size. One big stripping run then do your spirit run in the smaller boiler. It's more convenient than doing multiple stripping runs then a single spirit run. Adding a 2nd element cuts your stripping time in half. Upgrading the packing used. These kind of upgrades make the most impact in my opinion.

[Salt Must Flow]

water inlets have 90degree bends so the hoses don't kink.
silicone hose is gone

Can you provide more details on how you connected the hoses to the shotties?
1DCB40F7-7E9D-48D1-9404-AAD65FCAEE15.jpeg
Where did you buy your connectors from? What size and thread are they?

You can get fittings like this from Lowes, most hardware stores and even www.usplastics.com They come in all sizes and types.

I don't use elbows pointed straight down on my still. I have them pointing straight out like you do. I have velcro straps that secure the insulation to my column. I secure the hoses to the column so the hoses are more manageable.

[howie]

water inlets have 90degree bends so the hoses don't kink.
silicone hose is gone

Can you provide more details on how you connected the hoses to the shotties?
1DCB40F7-7E9D-48D1-9404-AAD65FCAEE15.jpeg
Where did you buy your connectors from? What size and thread are they?

i put SS camlock fittings on everything for water (not cheap), like my condensers,water hoses & cooling coil so it's all interchangeable/plug&play.
funnily enough, i went to my local hose & fitting shop yesterday to get a straight through adaptor ($15) as in photo.
the shop is Couplers in perth, but i suppose there are similar where you are.
NB i always take my gear in so they can sort the threads and sizes out for me.
these camlock fittings allow me to use almost the full 13mm diameter of the hose from my pump and have never given me any trouble.

[howie]

Hey @ericthered,

Yours are better quality than mine…9CB14636-5E5F-4983-BAE2-4D14931D3176.jpeg
I was wanting to build up a kit from better quality parts, but it would have cost me ~40% more, so I bought the premade kit instead. But heck if it works, that’s all that matters isn’t it?

@howie’s input gives me plenty piece of mind that this kit, slightly upgraded, will do what I want it to do.

I was thinking of building a dedicated stripping unit (I’m concerned about tarnishing the rig with flavoured spirits), and at that time I might buy some better quality parts for the neutrals still and retire esp. the shotties for service on the stripping still. Heck I could hook up the two shotguns in series to get a 5 tube x 600mm PC, as somebody suggested earlier. That would be a beast.

I love tri clamp, it’s like playing with Lego again!

there you go, overthinking again
it's pretty hard to tarnish SS.
as salt must flow said the fores/heads will clean most stuff out.
sometimes i do a quick steam run if the rig has been idle.(4l of water/full power/no cooling)
sometimes i dismantle the rig, which is very easy, after some heavy rum runs.
i always have have shallow bath full of starsan(ex fridge crisper drawer) that i can submerge all the parts if i need to.

i can strip 2 x 30l FFV ferments and have them loaded back in the fermenting fridge with everything cleaned up in 4 hours.
i hope you realise how long a reflux run can take on a 2"