Lpg Tank To Fermenter Ideas

[sosman]

I picked up an 80L SS LPG tank which I would like to make into a fermenter.

I was thinking for a lid just a flat perspex plate that I can clamp on to a rubber seal (kind of like that keg FV that someone posted). I will need some arrangement to clamp it down.

If I cut it below the port I will still have around 60L capacity. I could easily seal it with something see through if I wanted to keep maximum capacity.

The other challenge is getting it to stand up in the fridge. At the end of the day it is probably easiest to get something welded to it.

Also I am not sure whether it is worth putting two taps in, one at the very bottom to dump yeast and one a little higher.

Thoughts anybody?

 

[Pumpy]

Is it going to be heavy when you put it in the fermenting fridge ?

Pumpy

 

[sosman]

That mostly depends on how much I fill it. It will be heavier than a plastic one of the same size but the wall thickness is 1.7mm so it won't need a crane to lift it.

 

[Shed]

I would use it as a boiler.

 

[vlbaby]

I would be asking a few questions first about cleaning the ss properly. Years of exposure to lpg and the dye additives they add may have pentrated into the steel. Might give your beer a nasty sting or worse, if its not cleaned properly.

 

[sosman]

I would be asking a few questions first about cleaning the ss properly. Years of exposure to lpg and the dye additives they add may have pentrated into the steel. Might give your beer a nasty sting or worse, if its not cleaned properly.

It will get thorougly cleaned. One reason I want an SS fermenter is because of issues cleaning plastic ones.

 

[sosman]

I would use it as a boiler.

Shed - I have considered that however I am happy with my 50L boiler for now. If I start doing bigger batches that could change.

I can pick these up for $70 and 105L ones for a few more bucks if I want to go down that route.

 

[GSRman]

Are you *REALLY* sure it's stainless? most are mild steel Gal plated... and usually they only fail the borescope test if they are rusty... but if you can get the stainless ones for ?$70, you could probably sell them as scrap for more... and you might have issues with the welds on the inside... wont be as smooth as the outside..


BTW don't go cutting into it without getting it properly steam purged..

 

[kungy]

I don't know whether you have seen this guys awesome setup in america, but its a similar idea of using a SS tank for a AG setup. I am also sure he uses a similar setup for fermenting his beer as well. He has the advantage though as he uses pool filters there is a sealing unit that is already built in

http://forum.northernbrewer.com/viewtopic....ghlight=worthog

and also his complete setup

http://pg.photos.yahoo.com/ph/brewer007/al...er007/my_photos

Will

 

[sosman]

Are you *REALLY* sure it's stainless? most are mild steel Gal plated... and usually they only fail the borescope test if they are rusty... but if you can get the stainless ones for ?$70, you could probably sell them as scrap for more... and you might have issues with the welds on the inside... wont be as smooth as the outside..


BTW don't go cutting into it without getting it properly steam purged..

Stainless it is.

I got it from a scrap yard so if I could sell it back to them for more then there is a flaw in their business model. SS is only about $5-6 a kilo and that's what they sell these for.

They also have bigger ones (105L I think) for a few bucks more.

I will check out the welds internally once I decapitate it. Before I get the angle grinder out I want a bit of an idea of what the hell I will do with it - it might end up as a spit.

 

[ausdb]

Hi Sosman, do you plan on cutting one end out and putting a cone on it?
If so here is something I have worked out to make an access panel lid for my project to turn a 50L keg into a conical fermenter. This should work the same as what you are trying to do.

With your gas tank and a keg for that matter, both ends are formed on the same piece of machinery with the same curavture, on a keg the two deep drawn halves are then welded together and with your tank they are welded to a cylinder.

At the top of the tank cut out an oval shaped access hole (probably best done with a plasma cutter so it is neat) then cut the bottom domed section off and weld you conical part to it. With the spare end section cut out another oval piece to become your lid but make it about 20mm wider all round. You will then be able to turn it 90 to slip it inside the top oval opening and then back 90 so it can seal against the oval hole in the top of the tank as the curves shoudl be pretty close to the same (a bit of gasket material glued to the lid piece should form a seal). To hold this in place you will just need some sort of a clamp arm that pulls the oval hatch back against the other one. I will have the top chimb of the keg to use in this situation but it shouldn't be too hard for you to do something similar.

Just a suggestion

I have worked out with a 50L keg adding a 60 cone to the base of it will give it a capacity of about 60L which should be just right for double batches

Cheers

Ausdb

 

[sosman]

I was pondering whether to make a conical bottom. The reality is it will probably cost considerably more than the tank to do it. I don't have TIG gear nor the means to bend up the metal (although I can probably get the TIG done pretty cheaply).

The lid idea is neat but if I leave the dome on the bottom I won't have the spare.

I reckon it is possible to do the whole lot without any welding. The taps can just use bulkhead style fittings. For the lid I just need to figure out a clamping arrangement for a flat perspex cover (and rubber seal).

The dome is a poor man's cone

 

[JasonY]

Ausdb, will be interested to see how you go with the converting the keg idea. I would be interested in a setup like that! Are you going to fabricate it yourself or do you have someone in mind to do the welding etc. If there is an incentive to make two to save $ I would be interested.

My addition would be to stuff the idea of putting it in the fridge! I would just put a coil through the guts of it like a herms and use an idra pump to pump cold water through it. I have holes in the fridge already so a coulpe more wont hurt me. Cleaning would be harder but who cares, it could sit outside by the kegerator and the missus would be happy.

Starting to dream of stainless fermenters! B)

 

[pint of lager]

Was browsing your ideas about using an lpg tank for a fermenter.

My concern is that even after thoroughly cleaning it, steam cleaning, etc, it may still contaminate your brew.

From my understanding, the metal will have absorbed some of the gas, which will slowly leach back out over years. But I have had no direct experience with lpg in ss containers, so may be talking air.

The cylinder would have been under pressure, so even more gas would have permeated the steel.

I do know that welders take great care when working on old empty fuel tanks, even filling with water when cutting.

Maybe as a test for its suitability of fermenting in, fill it with water for a few days/weeks, then taste the water for any off flavours from the gas.

Keep yor eye on that scrapyard, you never know what you can pick up. We have all sorts of nice ss ball valves, ss lines, etc sourced from our local yard.

 

[Justin]

There is a thread about keg/conicals on the HBD Brews and Views forum atm with pictures.

Don't forget guys that actually buying a 12.2G hopper straight from toledo metal spinning may very well be a cheaper easier option than fabricating the whole thing yourself. Especially if your happy to build a stand and do your own fittings (you'll be doing that anyway). There are also weldless options for the fittings (however I would build my own weldless fittings rather than buying the overpriced zymico ones).

The 12.2G hopper is only $152US, plus some shipping. Shipping can't be that much and I'd guess you would see one at your place for about $250AUD (I did enquire at one stage but can't remember specifics). Morebeer have them (hopper only, but dearer than direct from toledo-but they will give you a shipping weight) so you could work out the shipping price for one. Unfortunately morebeers website doesn't seem to be working for me at the moment.

www.toledometalspinning.com

Cheers, Justin

 

[sosman]

Thanks for the comments so far.

Re the LPG/dye ingress into the tank - I will further investigate however there is no obvious staining or odour.

I am not that desperate for a new fermenter so I won't be splashing out 100's of dollars to order a conical - I have this tank and if I can make something from it without breaking the bank then that is good.

Even some aluminium foil and a big rubber band would do me for a lid - it doesn't have to be high tech.

As for running a cooling coil, I was thinking the same thing but would probably wrap it around the outside then insulate it.

 

[JasonY]

Well I am not sure what LPG you guys use but the stuff we make at the refinery is not dyed. Simple reason for this is that it will become a gas very quickly if you put it anywhere that you get the oportunity to look at it .

It will be stenched with Ethyl & Methyl Mercaptins which give that smell so you have a warning before you blow yourself up! h34r:

I don't know how much stuff will be absorbed into the stainless. I would wash it well, fill it up with water and boil the sh#t out of it, can't imagine much surviving that. Pint of Lager's suggestion about filling with h20 for a while is also a good one.

Certainly a nice looking vessel.

 

[sosman]

I do know that welders take great care when working on old empty fuel tanks, even filling with water when cutting.

Lager - I have done that too. The only reason I have ever done that is because of residual petrol fumes from pockets of petrol, not because it has been absorbed into the steel per se. The theory is that if it is full of water then there can't be petrol vapour in there.

 

[vlbaby]

I think you've got a good point, pint of lager. Stainless Steel like most metals is porous to a certain extent, and over time the metal would have absorbed the lpg and the odor additives into the metal. Probably find it will slowly leach back out over time. Its possible you might be able to clean it by accelerating this leaching by boiling or something similar.
I have read a little about what is considered food grade, and although stainless and many other plastics etc are food grade, if they have contact with any non- food products,chemicals etc, then they are considered not to safe to use as food grade.
I'd be cautious myself, you might be slowly poisoning yourself.

 

[Justin]

Just on this topic I had been considering for some time trying to find some of the petrol tanks that you see on the sides of big trucks. From a wreckers or somewhere I thought these may have yielded some good sized stainless vessels. Keen to see the outcome of this project/idea.