The perfect fermenter design

[CPESystems]

Hi Guys,

Everyone has their own opinion of course as to what a perfect fermenter would look like but I thought it would be interesting to see if we can get a consensus or a least a partial agreement. LOL

So first off can we agree on geometry?

Height to diameter ratio" 2 to 1?
Angle of the bottom cone 60 deg?
Top style ASME dish?
Manway (s) Side only or side and top?
Legs 3 or 4?

[grnis]

That depends on what kind of beer you want to ferment.
CCV for lager is pretty much standard.
CCV for ale is increasingly common, but for ale I'd prefer shallow tuns rather than tall cylinders.

And a cone angle of 65-70 degrees is most common. I think.

[Kushal]

In a perfect world I would have a cat walk at the top of my perfect fermenters and there would be no side door, only top. But in an unperfect, catwalk free world I settle for a big dry hopping port on top and definitely a strong anchor point for a safety harness.

2 separate arms for blow off and cip.

Temp probe low in the tank so you can ferment properly if you had a short brew.

Some better system for turning racking arms that doesn't require loosening a clamp.

[liammckenna]

Hi Guys,

Everyone has their own opinion of course as to what a perfect fermenter would look like but I thought it would be interesting to see if we can get a consensus or a least a partial agreement. LOL

So first off can we agree on geometry?

Height to diameter ratio" 2 to 1?
Angle of the bottom cone 60 deg?
Top style ASME dish?
Manway (s) Side only or side and top?
Legs 3 or 4?

Depends on size and application (type of beer, etc) and preference of course. For cylindroconicals, my ideal:
2:1 is a good ratio I think for the cylinder. The cone is additional to this . I find the longer the cone the better for better control in yeast harvesting. I also insist on cooling jackets on the cone.
Dish top? Many prefer different. Dish suits me.
Top and side shadowless manways or a suitable top access port for service/dry hopping.
Easily removable sprayball(s)/jets.
25% headspace.
I second the separate vent /CIP lines
Ideally, jackets and probes would be efficiently designed to allow for half batching.
I like legs in threes and fives (for bigger tanks).
Mirror polish interior finish.
Robust, cleanable, easily serviceable sight glass design.

Pax.

Liam

[CPESystems]

Sightglass

Hi Liam,

"Robust, cleanable, easily serviceable sight glass design"

Do you mean a sight level gauge on the side or a round view port?

[cervezale]

headspace

Why are tanks manufactured almost exclusively with 25% headspace if some ale fermentations can require 40% headspace according to Kunze?

[Bainbridge]

Some better system for turning racking arms that doesn't require loosening a clamp.

Amen.

But a big ol' dryhopping port is a must nowadays. (Unless your tank is big enough to justify Hop Cannon shenanigans.) I've been thinking along the lines of getting like a steel funnel welded onto a 4" TC for ours, so I can take the cap off, clamp the funnel on, then just easily and slowly pour the bucket of hops in.

[porter]

I second that!

In a perfect world I would have a cat walk at the top of my perfect fermenters and there would be no side door, only top. But in an unperfect, catwalk free world I settle for a big dry hopping port on top and definitely a strong anchor point for a safety harness.

2 separate arms for blow off and cip.

Temp probe low in the tank so you can ferment properly if you had a short brew.

Some better system for turning racking arms that doesn't require loosening a clamp.

I second the racking arm design! Are there any that don't require loosening a clamp?

What about a fitting with a tightening ring like the one on my GW Kent Bulldog barrel racking setup? There is a tensioner with an internal gasket. Does anyone make racking arms like that?

[liammckenna]

Hi Liam,

"Robust, cleanable, easily serviceable sight glass design"

Do you mean a sight level gauge on the side or a round view port?

Sight level gauge/tube on the outside side for measuring internal volume in a pressurized tank tank. I have seen some pretty flimsy designs in the past where they seem to leak if you even touch it.

Pax.

Liam

[dick murton]

Why are tanks manufactured almost exclusively with 25% headspace if some ale fermentations can require 40% headspace according to Kunze?

They are manufactured with whatever headspace you want providing you tell the manufacturer. Most bottom fermenting yeasts in large lager breweries only need 20 to 25% headspace as the yeast does not form a head at that temperature, and is relatively non head forming anyway.

Ales traditionally use a top fermenting yeast, and is fermented at heigher temperatures. The yeast forms a dense top cropping yeast, so needs loads of space else it starts to climb out of the fermenter. Since the big brewers, of whom there are not many, if any producing brewlengths of say 500 hl + in CCVs will tend to use bottom fermenting variants of the original top cropping yeast, they also don't need so much headspace - so 20 - 25 % is OK.

The headspace required varies enormously with yeast type, temperature and other conditions. For instance one brewery I worked at, we brewed 480 - 490 hl of 12P wort in a CCV, but if we fermented the 26 P barley wine, then we had to aerate the wort heavily, so we could only ferment 350 hl, and had to apply top pressure to stop it climbing out of the top.

Now you need to be clear what the term refers to. Is it % of total vessel capacity, or % of fermenting wort? Sometimes people give different figures.

In a nutshell, you need to have a feel for what headspace your yeast is going to need, and specify differently if your yeast / fermentation conditions need more space. In general - high temperature top fermenting ales need more than cooler bottom fermenting lagers, with cool top fermenting beers somewhere in between.

[cervezale]

It's great to have the theory backed up by some useful "real world" cases as in the barley wine anecdote. It is incredibly generous of seasoned brewers to share their experiences with people starting out in the field. Thanks you all.

[Luch15]

I second the racking arm design! Are there any that don't require loosening a clamp?

What about a fitting with a tightening ring like the one on my GW Kent Bulldog barrel racking setup? There is a tensioner with an internal gasket. Does anyone make racking arms like that?

Yeah this is a nice feature. We have a few from GW Kent that have DIN fittings on the racking arms, at first I wasn't a fan but I really like them now because you don't have to loosen anything to turn the racking arm. Another good design is the one Prospero uses, on their fermenters they have a racking arm that turns on the inside of the tank without turning the valve on the outside or needing to loosen a clamp, really nice. I add my vote for a nice big port on top for dry hop, etc.