Secondary Containment--Fermenters (Glass vs. Plastic)

[analyticalalchemist]

All,

First, I am in the research stage of brewing beer. Also, I am an analytical chemist/engineer and secondary containment is a procedure often used in waste containment and hazmat shipment. I tried to search the forums to see if this topic had been mentioned before but I came up with nothing--Just thought I would share my ideas.

Second, let me preface this post with the fact that I have been going back and forth trying to determine whether or not to use a glass or or plastic (better bottle) carboy. I have decided to use a glass carboy with a blow off for my primary but the horror stories of blown-shattered carboys for primary fermentation has me spooked. My idea is to use a garbage can to contain the primary fermenter to protect my apartment from a blown fermenter. I think this is a good idea and I am going to use it in my first brew situation. In the future, I will report on the pros and cons of this technique. But, from past experience--basically chemistry demonstrations--I think this may be a cheap (10$) solution to the blown/shattered primary fermenter situation. You can simply use a small hole in the top of the garbage can to sort/route tubing or release carbon dioxide and the plastic can will likely stop most, if not all, damage to personal property.

Please leave your thoughts-I'm a total noob, but I love science and can't help but share...

Thanks,

Analytical Alchemist

 

[BrewinJay]

I have never used glass as my primary, but am considering it, but if my science is correct as long as you have a blow off tube then there is no way that the carboy will build up enough pressure to blow. unless something clogs the blow off tube, then it will build up pressure, but as long as you check your tube and clear it if needed then you should not build up pressure. just my thoughts though, like I said I have never used a glass carboy for my primary.

 

[lamarguy]

I have been going back and forth trying to determine whether or not to use a glass or or plastic (better bottle) carboy.

My idea is to use a garbage can to contain the primary fermenter to protect my apartment from a blown fermenter.

Analytical Alchemist

Try to search with a bit more "effort" next time. There are hundreds of threads on glass vs plastic, carboy vs whatever container, etc.

Yes, people have imploded their glass carboys from plugged blowoff tubes. It's glass, it's amorphous, it'll separate violently into hundreds of tiny, sharp pieces sometimes with provocation, sometimes without.

Some people have the gumption to wrap their glass carboys in plastic dip, box tape, care bears, etc. in an attempt to contain the danger that is, well, glass. Some people just avoid glass altogether and sleep much better knowing their plastic fermentation vessel isn't vying to send them to the hospital...

 

[nebben]

First off, get the exploding fermenter thing out of your head. It shouldn't ever happen unless you're being extremely careless and it can easily be avoided. Leave adequate headspace above your wort and if in doubt, play it safe and just fix up a good size blowoff tube.

If you have the room, it doesn't hurt to have a carboy (better bottle or glass) in a rubbermaid container or something. If you are expecting a hyper fermentation and use a blowoff tube, it is a convenient spill containment vessel to hold your fermenter+bubbler. If it is too warm for your fermentation, you can fill the can/rubbermaid partway with water and do the swamp cooler thing. If it is too cool, ditto as before but put in a fish tank heater. Versatility. Plus, you're less likely to knock it over it if it happens to be sitting in your living room!

It wont help if you drop your carboy, however.

 

[Zen_Brew]

I don't think the primary concern with glass carboys is them exploding during fermentation. I'm not saying it can't happen, it just isn't likely unless you have really gummed up your escape ports for the co2 through your blowoff or airlock.

The hazard that is more prevelant, and I don't mean to imply likely, just the scenario that happens when something does happen, is that there are some unseen stress fractures in the carboy. These could be from you knocking the carboy against a hard surface, or from shipping stress, or from original time of manufacture. Anyway you are happily and carefully cleaning your carboy, and the stress of the hot water coupled with the pressure of the water causes the stressed area to give way. Sometimes the bottoms just literally fall off in your hands. I have read of some pretty scary injuries. Then again there is always the risk of dropping a carboy while it is wet and slick with cleaning agents.

Again, most people use glass carboys with no problem at all, and many will likely post and say as much. It's just that in the rare event one of them does let loose, it is usually not during fermentation.

 

[homebeerbrewer]

I have a horror story about a broken glass carboy, but it isn't stopping me from using it. As lamarguy pointed out, I tested the Plasti Dip on a carboy, and the results do look promising.

As for the glass breaking during fermentation due to pressure buildup, you don't need to worry about that. If you use a rubber stopper with an air lock or blow off tube, even if it gets clogged, the weakest point in the vessel would be the stopper. A little bit of pressure is all that's needed to push the stopper out. Of course, having the carboy in a bucket will contain the resulting spill.

Disclaimer: anything can happen, so if you do break your carboy, I'm not at fault. I will continue using mine though.

 

[user 30639]

Yeah, I would think you'd have to have a glass carboy completely plugged up to have it explode on you.

 

[greenleer]

As for the glass breaking during fermentation due to pressure buildup, you don't need to worry about that. If you use a rubber stopper with an air lock or blow off tube, even if it gets clogged, the weakest point in the vessel would be the stopper.

Exactly. The lid to a plastic fermenter is probably sealed on much tighter than the stopper in a glass carboy. Nobody seems to be worried about exploding buckets -- just the lids blasting off of them. :rockin:

 

[koomber]

See if where you work has any 25L Jerry cans sitting around. They are MAGIC ofr brewing. You get a nice bit of head room and best of all, some of them can be stacked. Even with a blow of tube fitted. As another bonus, they typically have a shape on the base that (with a little propping during the OMG fermenting) can allow the bulk of the yeast to collect on one side, and make for easier syphoning. Also, you can buy all sort of odds and ends for them.

Any lab/chemist worth their salt will be able to lay ther hands on some silicon tubing. That makes a perfect blow off tube.

I submit this answer to you as a fellow chemist (though I work in the oil industry, which doesn't really count). I just need to convince the boss at work to let me use som of thier pilot plant equipment for doing brews and the I'LL be set

 

[analyticalalchemist]

Try to search with a bit more "effort" next time. There are hundreds of threads on

Ouch! If you read the post it wasn't focused on the glass or plastic question. I have read many post related to that debate.

I thought it was pretty clear that I am going with glass and just wanted to see if the idea of secondary containment, rather than reinforcing the structure (plastic dips, etc.), had been mentioned. I was simply trying to throw an idea out there for others to potentially use.

Anywho, have a good one and sorry if I wasn't clear--My bad.

Also, to others, I am am very aware that the cap or plug would likely fail before the carboy, but I was concerned with, as others have mentioned, stress fractures and imperfections in the amorphous structure of the carboy. As many have stated, the shards from one of these things would be large daggers (not tempered glass) and could cause real pain. My inner nerd just loves the idea/aesthetics of glass--Chemists love new glass toys!

Thanks for your replies...

 

[geckosan]

that title just made me think of one movie quote...

"Tell him about the twinkie" -Winston

 

[Krelja]

One of my 6.5 gallon glass carboys is from 1951 according to the markings on the bottom. I've never had any problems with it. The things I do to keep it that way is never putting it on concrete or any other hard abrasive surfaces. I guess it just depends on how/where it was made. Newer made in china ones might be more apt to break but who knows. I'm sure there are people who have broken glass carboys and not gotten injured. I would never secondary in anything but glass for long periods of time. I think it's just in my head. I do use better bottles but I have that when you go to move them since they are thin they seem to move the liquid around alot more than glass. I'm not going to bash either vessel but I like glass and remember opinions are like a$$holes everyones got one and they all stink just like the glass vs plastic debate.

 

[Ksosh]

While I like the idea of the garbage can, I'd also recommend getting a milk crate (a real one, from a dairy farm, not the **** they sell at Target for dorm rooms), and put your carboy in that. It makes it much easier to lift and carry a carboy when it's full, protects it from smacking against hard surfaces, has enough room in the corners to put frozen water bottles (for a swamp cooler) and is free (assuming you're near a dairy farm or something similar).

 

[analyticalalchemist]

I love this idea--Good stuff! I deal with glassware all the time and having that plastic layer will definitely help stop potential scratches and crack-nucleation sites that could lead to future failure of the glass. I was thinking of going with a handle, but they seem to be placed at a potential week point of the carboy--This idea is much better!

Thanks!

 

[Synovia]

I secondary in cornies. They're cheaper than glass, and just as impermeable, and they won't wound you if you drop one. They won't even spill the beer.


Theres no real reason NOT to primary in plastic.

 

[Scut_Monkey]

I agree with what everyone is saying. During primary is not when carboys "explode" it's during movement and cleaning either from dropping or stress fractures like already mentioned. I personally don't feel that they are that dangerous and my 5 gallon carboy works great but I do think they carry a risk. Personally I don't want to worry about it so I found an old army bag that I have and plan to use that to carry the carboy in. I still haven't decided if I want to go the route of better bottles as they are overpiced PET Culligan bottles from what I have researched. I still don't understand why they can't make a 7gal better bottle????

 

[Scut_Monkey]

I secondary in cornies. They're cheaper than glass, and just as impermeable, and they won't wound you if you drop one. They won't even spill the beer.


Theres no real reason NOT to primary in plastic.

Too bad I didn't read this before I posted. I think to do a secondary in a corny is a perfect idea. They block all UV and air and are relatively inexpensive as I can get them for $25 each locally. When you go to sample or dry hop or add anything simply take the lid off and dump it in. I realize this isn't a new idea but it's something I never really considered until now.

Can anyone think what a disadvantage to using a corny would be compared to glass or plastic carboys? Assuming you had an airlock on it.

 

[Picobrew]

Can anyone think what a disadvantage to using a corny would be compared to glass or plastic carboys? Assuming you had an airlock on it.

Just the cleaning. Quite a few people on here do this. I have used it as a primary fermenter as well as secondary.

To the original poster, ditto what everyone else said: the main danger is when you move the carboy, clean it, etc. Slippery hands, a heavy glass object.... it's dangerous. Secondary containment there is usually pretty loose: a carboy koozy, a milk crate, a canvas bag, etc. Really hard when you are cleaning it and rinsing it.

 

[Krelja]

Instead of using the carboy holder that goes around the neck(which I thought was in a bad place too) you could use this. The Brew Hauler
I haven't bought one yet but its in the future. I've never felt uncomfortable yet moving the thing around. Since it wraps around the bottom it should also help protect the bottom from hard surfaces due to the nylon on the bottom