Big mouth bubbler closed transfer!

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toddnlinn

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Does anyone have any input on how I can do as much as possible use my dual port lid on the BMB rig it to use CO2? I’m searching but coming up empty! Video or pics and what type of equipment! Thanks
 
I assume you mean to kegs. This is how I did it, with a keg that was purged with CO2:

closedloopco2.jpg


The goal was to feed that displaced CO2 back into the fermenter. I used an airlock and cut the top part off so the tubing would fit, but you can use a drilled stopper with a piece of rigid tubing in it.

With your two-opening BMB lid, simply plug one up with a solid stopper, or plug the hole in a drilled stopper.

Is this what you had in mind?

BTW, if your BMB doesn't have a spigot, I'd suggest getting one. Drill a hole and there you are.
 
That looks awesome. Any ideas on a one that does not have the spigot?

Some people will put a siphon through one hole, and return the displaced CO2 through the other.

My original BMB didn't have a spigot. When I bought a second BMB, I took a chance and bought one with a spigot. One use and I bought an extra spigot and refit the first one with it. I've never used a siphon since then.

I ended up at one point having five of them--all of which had spigots.

They're cheap. Here's one from Ritebrew: http://www.ritebrew.com/product-p/841228.htm

I'll bet your LHBS has them.
 
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So glad I found this thread. My only question is, how much pressure you put in the keg?

I'm not sure what this means. The keg, though purged with CO2, isn't under any pressure during the transfer. You're simply racking/draining the wort into it and the CO2 that is displaced as the keg fills goes back into the fermenter.

This is different than a pressure-transfer where the fermenter is pressurized which helps push the wort into the keg. To do that you need a fermenter that can handle the pressure, including the lid and any stoppers and such.

I tried some pressure transfers with the Bigmouth Bubbler, and every time when pressure became too great the lid would pop off. If you had a screw-on lid (the original version) or another fermenter like the fermonster whose lid screws on, that's less of a problem. It also creates a new potential one, which is what happens if some other part lets go and you start spewing wort all over?

I also tried really low pressure CO2 as a way to replace the wort as it drained away, and not replace it with air. I couldn't see that it made any noticeable difference.
 
I've done it two ways. In both, you want your fermenter floor to be higher than the top of the keg. I set mine on the lid of the chest freezer I ferment in and put the keg on the floor.

  1. With a BmB that did not have a spigot. I had a dual port lid. I had a stopper with a racking cane in one and attached a CO2 tank to the other using a barbed piece of plastic. I'd start with a pre-purged keg. Put just enough pressure to force some beer up the racking cane and which starts a siphon, which goes into the liquid out of the keg. As soon as it starts flowing, I switch the CO2 into the fermenter with a hose coming off the gas in on the keg. As the keg fills, it displaces CO2 which goes into the fermenter filling the space vacated by the beer that's draining.
  2. With a spigot, it's much easier. I connect the gas in port on the keg to a barbed connected on the one port lid. Connect the output spigot on the fermenter to the liquid out port on the keg. Open the spigot and the beer flows into the keg, displacing CO2 which goes out the gas port and into the fermenter, replacing the space vacated by the beer flowing out.
    One thing I do that complicates this a bit, is I start with very low flow CO2 from a tank into the fermenter and drain the first bit of beer into a bucket until it runs clear. This prevents me from getting any trub in the keg and also ensures that the oxygen in the liquid line is purged before connecting to the keg.
I definitely recommend a spigot. I didn't need a second fermenter because I don't really ever have two beers in primary at the same time (I don't even have room in my ferm chamber for that), but after reading about how easy they are and having many slow/stalled transfers due to siphons that were disrupted by trub, I switched. I went from half hour transfers to 10 minute transfers.

Mod your BmB or get a new one.
 
I need to do a closed transfer to keg soon on a super hoppy NEIPA from a BMB with a spigot and single stopper lid so I'm excited to see this thread. Everything I read is oxygen is really important to eliminate on these kinds of beers so I want to be very careful.

Toddnlinn - did you try this? If yes, how did it work out for you? Any changes you would suggest?

The keg, though purged with CO2, isn't under any pressure during the transfer. You're simply racking/draining the wort into it and the CO2 that is displaced as the keg fills goes back into the fermenter.

Mongoose33 - what is the best way to purge the keg with C02? I've read some use water, then pump out with CO2 and others use StarSan. I guess you have to sanitize it anyway. Can you include a close up of both your modified airlock and the keg connections?

Hwk-I-St8 - can you include pics of your setup for the one with the spigot? Sounds like you are using a barbed fitting into the stopper rather than an airlock like Mongoose33?

Thanks in advance
 
Mongoose33 - what is the best way to purge the keg with C02? I've read some use water, then pump out with CO2 and others use StarSan. I guess you have to sanitize it anyway. Can you include a close up of both your modified airlock and the keg connections?

I think you might be making this too hard. I fill my keg with Star-San, then let CO2 bubble up from the bottom (Black liquid OUT QD on the line for this). I let it bubble up enough that the entire headspace and under the lid is filled with those bubbles which contain....CO2. Then with the bubbles coming out, I affix the lid at which point I have a keg full of Star-San plus CO2 bubbles.

Then I switch the OUT post to a jumper (could be a line that just drains into a 5-gallon bucket to reuse the star-san). I then use CO2 to push out the Star-San into another keg (or the bucket), leaving me with a keg pressurized with CO2. Purged in other words, but also with some pressure.

Then I grab a racking line. It's tubing that fits over the spigot, and attaches to a black QD. I take that to the sink, and push the QD on there, which causes the pressure to come out of that tube. I rock the keg a bit to blow out any residual star-san, but I stop, i.e., remove the racking line, before the keg completely depressurizes. I want a little residual pressure.

Then I move the keg over to the BMB, spray the spigot again with star-san, and then attach the racking line. Residual CO2 pressure comes out, and just as the pressure subsides, I point it to the spigot and clear any air out of it and attach the line. Now the racking line is full of CO2, so is the keg, so all that's left is to take the displaced Co2 from the keg and feed it back into the top of the fermenter as it drains into the keg.

When I first did this, i couldn't find any tubing that would fit the line, but I discovered an airlock with the top removed would serve. This way the CO2 that is displaced from the keg as it fills is fed back into the fermenter, instead of air that has 21 percent O2 in it.

A few pics that I hope show this more effectively than my prose above:

CO2purgebubbles.jpg


jumper.jpg



jumperoneside.jpg
o2freeracking2.jpg
 
I think you might be making this too hard. I fill my keg with Star-San, then let CO2 bubble up from the bottom (Black liquid OUT QD on the line for this). I let it bubble up enough that the entire headspace and under the lid is filled with those bubbles which contain....CO2. Then with the bubbles coming out, I affix the lid at which point I have a keg full of Star-San plus CO2 bubbles.

Then I switch the OUT post to a jumper (could be a line that just drains into a 5-gallon bucket to reuse the star-san). I then use CO2 to push out the Star-San into another keg (or the bucket), leaving me with a keg pressurized with CO2. Purged in other words, but also with some pressure.

Then I grab a racking line. It's tubing that fits over the spigot, and attaches to a black QD. I take that to the sink, and push the QD on there, which causes the pressure to come out of that tube. I rock the keg a bit to blow out any residual star-san, but I stop, i.e., remove the racking line, before the keg completely depressurizes. I want a little residual pressure.

Then I move the keg over to the BMB, spray the spigot again with star-san, and then attach the racking line. Residual CO2 pressure comes out, and just as the pressure subsides, I point it to the spigot and clear any air out of it and attach the line. Now the racking line is full of CO2, so is the keg, so all that's left is to take the displaced Co2 from the keg and feed it back into the top of the fermenter as it drains into the keg.

When I first did this, i couldn't find any tubing that would fit the line, but I discovered an airlock with the top removed would serve. This way the CO2 that is displaced from the keg as it fills is fed back into the fermenter, instead of air that has 21 percent O2 in it.

A few pics that I hope show this more effectively than my prose above:

View attachment 649330

View attachment 649327


View attachment 649328 View attachment 649329
When you attach the gas side to the air lock, do you just let it push whatever liquid is in the airlock into your fermenter or is the pressure low enough to keep the airlock in place?
 
This is how I do mine. I don't loop the co2 back into the fermenter. Usually I have enough beer on top that the little amount of exposure to o2 isn't going to make it into the keg. Maybe that's BS, but I'm OK with it. I take the airlock off and cover with sanitized foil. Make sure the gas is out of the keg before starting the beer flowing into the keg or you'll get blowback into the fermenter. Suppose this could be solved by looping the co2 back into the fermenter...🤔
IMG_20200817_184716641.jpg
 
This is how I do mine. I don't loop the co2 back into the fermenter. Usually I have enough beer on top that the little amount of exposure to o2 isn't going to make it into the keg. Maybe that's BS, but I'm OK with it. I take the airlock off and cover with sanitized foil. Make sure the gas is out of the keg before starting the beer flowing into the keg or you'll get blowback into the fermenter. Suppose this could be solved by looping the co2 back into the fermenter...🤔View attachment 702696
But with this setup, as the beer is being put into your keg (and removed from the fermenter), something has to replace the space inside of your fermenter. Oxygen will be pulled into the fermenter and the foil on top isn't going to stop that. Therefore, you are exposing the beer to oxygen as it's being pulled into the keg.
 
When you attach the gas side to the air lock, do you just let it push whatever liquid is in the airlock into your fermenter or is the pressure low enough to keep the airlock in place?

That isn't the airlock normally used. It's a different one with the top cut off so the hose would connect to it.

I just swap airlocks though if I could find a way to keep fruitflies out of the cutoff one, I'd have used that.

I've found with this stuff that the key is to understand what I'm trying to do, then adapt to the equipment I have available. That's what happened in this case--I had some vinyl tubing that just happened to fit the neck of an airlock if I cut off the top with the cap. There's nothing holy about using an airlock to do this--it just already fit the drilled stopper in the top, and with the top cut off it fit the vinyl tubing I had.

If I'd had different tubing a different solution would have been crafted.

Here's an example: a few years ago someone was selling some 5/16 silicone tubing on HBT, and I bought some. Turns out I use it for a ton of stuff. One thing I found is that if I cut off the end from a bottling wand, that would perfectly fit the 5/16 silicone tubing.

Well. That meant I could use that little bit of rigid (bottling wand) tubing in a drilled stopper on top of a fermenter and use that tubing to feed an airlock in a jar. That led to me using that in a small dorm-size refrigerator I use as a ferm chamber, and I used that to feed fermentation gases out of a fermenter in my larger ferm-chamber refrigerator.

I like seeing the bubbling, it's a good way to monitor the tempo of fermentation.

Here are a couple pics. The key is to find a way to either recycle the gas being pushed out of the keg and back into the fermenter, or feed the gas off the fermenter when it's working, or....whatever.

ministoppertubing.jpgminifridge2.jpgminigrommets.jpgnewsetup2.jpg


*****************
I just kegged my 93rd batch. I've gone from a basic BMB fermenter to a Spike CF10 unitank, from using a small propane burner to a Blichmann Hellfire to electric brewing. I had a small immersion chiller, graduated to a Jaded Hydra and now to a stainless counterflow chiller.

Along the way, I developed an approach to brewing that has worked wonderfully well. I just keep trying to do better.

Every time I read something about "best practices" I'd consider it and if it made sense--most do--I'd try to incorporate it into my brewing.

One of those things has to do with oxygen. With the exception of oxygen needed by yeast, O2 is generally bad for beer. So I do everything I can reasonably do to keep oxygen away from my beer.

But the general principle holds: keep trying to do things better. Along the way to 93 batches, something magical began to happen: my beer began to be really good. REALLY good. Enough that friends want to pay me commercial prices for sixpacks, a local bar wants to sell it. Can't do that, no license, but I consider that a measure of my beer's quality.

There's a term for this: continuous quality improvement. It's not the fastest way to the goal line, but it is the most certain. It works. Just keep trying to find ways to get better.
 
But with this setup, as the beer is being put into your keg (and removed from the fermenter), something has to replace the space inside of your fermenter. Oxygen will be pulled into the fermenter and the foil on top isn't going to stop that. Therefore, you are exposing the beer to oxygen as it's being pulled into the keg.
Of course, but as I said, I usually have some beer leftover which, I would think, is the beer that is most exposed to the o2 not making it into the keg. It's not perfect but it works pretty well. I tried doing the closed loop once and the beer didn't move, just stayed there. Not sure why.
 
That isn't the airlock normally used. It's a different one with the top cut off so the hose would connect to it.

I just swap airlocks though if I could find a way to keep fruitflies out of the cutoff one, I'd have used that.

I've found with this stuff that the key is to understand what I'm trying to do, then adapt to the equipment I have available. That's what happened in this case--I had some vinyl tubing that just happened to fit the neck of an airlock if I cut off the top with the cap. There's nothing holy about using an airlock to do this--it just already fit the drilled stopper in the top, and with the top cut off it fit the vinyl tubing I had.

If I'd had different tubing a different solution would have been crafted.

Here's an example: a few years ago someone was selling some 5/16 silicone tubing on HBT, and I bought some. Turns out I use it for a ton of stuff. One thing I found is that if I cut off the end from a bottling wand, that would perfectly fit the 5/16 silicone tubing.

Well. That meant I could use that little bit of rigid (bottling wand) tubing in a drilled stopper on top of a fermenter and use that tubing to feed an airlock in a jar. That led to me using that in a small dorm-size refrigerator I use as a ferm chamber, and I used that to feed fermentation gases out of a fermenter in my larger ferm-chamber refrigerator.

I like seeing the bubbling, it's a good way to monitor the tempo of fermentation.

Here are a couple pics. The key is to find a way to either recycle the gas being pushed out of the keg and back into the fermenter, or feed the gas off the fermenter when it's working, or....whatever.

View attachment 702697View attachment 702698View attachment 702699View attachment 702700


*****************
I just kegged my 93rd batch. I've gone from a basic BMB fermenter to a Spike CF10 unitank, from using a small propane burner to a Blichmann Hellfire to electric brewing. I had a small immersion chiller, graduated to a Jaded Hydra and now to a stainless counterflow chiller.

Along the way, I developed an approach to brewing that has worked wonderfully well. I just keep trying to do better.

Every time I read something about "best practices" I'd consider it and if it made sense--most do--I'd try to incorporate it into my brewing.

One of those things has to do with oxygen. With the exception of oxygen needed by yeast, O2 is generally bad for beer. So I do everything I can reasonably do to keep oxygen away from my beer.

But the general principle holds: keep trying to do things better. Along the way to 93 batches, something magical began to happen: my beer began to be really good. REALLY good. Enough that friends want to pay me commercial prices for sixpacks, a local bar wants to sell it. Can't do that, no license, but I consider that a measure of my beer's quality.

There's a term for this: continuous quality improvement. It's not the fastest way to the goal line, but it is the most certain. It works. Just keep trying to find ways to get better.

Very nice. I'm pretty new to it compared to 93 batches. Was considering jamming something like this into a drilled stopper and using that to do the closed transfer with QD's instead of the cut-off airlock that was previously shown. Hopefully I can have the time and money to continue to improve my setup over the years as well.
1602860156748.png
 
Of course, but as I said, I usually have some beer leftover which, I would think, is the beer that is most exposed to the o2 not making it into the keg. It's not perfect but it works pretty well. I tried doing the closed loop once and the beer didn't move, just stayed there. Not sure why.

I think you're right about the exposed beer, but the closed loop thing seems like the same or even less work - no bucket needed. I'd suggest trying again and being sure you didn't inadvertently have something closed or clogged. Maybe gravity wasn't quite enough to overcome the relatively small holes in the keg posts / poppet valves?

I'll definitely try this out the next time I keg which is hopefully in a week or so, have a porter that's about ready.
 
Very nice. I'm pretty new to it compared to 93 batches. Was considering jamming something like this into a drilled stopper and using that to do the closed transfer with QD's instead of the cut-off airlock that was previously shown. Hopefully I can have the time and money to continue to improve my setup over the years as well.
View attachment 702701

That'll work fine provided that the hole in the stopper is small enough.

Over time I've gathered a parts box full of this and that, and if I think hard enough sometimes I can get some of that stuff to work for me.

The pics above show one of those things. The small dorm-type ferm chamber fridge doesn't have enough clearance for an airlock to stick up--the freezer is in the way. Many people bend that down, but I wasn't comfortable doing that. So I stuck that rigid plastic tube in a stopper and attached the silicone hose to it. I wanted to run that line out of the refrigerator to an airlock jar, so I drilled a hole in the very front, put a grommet in the hole, and passed the silicone line through it. Voila! I can monitor fermentation activity without opening the refrigerator.
 
@mongoose33 I'm thinking about getting a Big Mouth Bubbler and trying out this set up. Do you ever have issues with trub or hop sediment getting into the keg? I am particularly concerned with IPAs that have an ~8 oz dry hop.

I could imagine propping the fermenter up a few inches right under the spigot so that everything settles at an angle, clearing more room for the beer. I could also see using the depth charge dry hop filter, but its kind of pricey. Today I use a mesh steel filter that fits over my auto-siphon, so I don't like the idea of no filter.
 
I've done this every brew since my last comment on this (closed transfer with BMB to keg), it's great.

I have only once had a problem, and yep it was hops clogging the poppet in the post. I've basically just learned to be sure it's all settled out and not to jostle it. Only at the end do I start moving it around, at a point where there's not much left anyhow.

Your idea of pre-tilting it should be perfect if you expect a potential issue. That is indeed a lot of hops. Tilt it a day or two ahead of time and I expect you'd be just fine. Then you'll know for next time if you even have to bother - the spigot's a decent ways up, it might be enough, but I do like a first-time tilt just in case.
 
@mongoose33 I'm thinking about getting a Big Mouth Bubbler and trying out this set up. Do you ever have issues with trub or hop sediment getting into the keg? I am particularly concerned with IPAs that have an ~8 oz dry hop.

I could imagine propping the fermenter up a few inches right under the spigot so that everything settles at an angle, clearing more room for the beer. I could also see using the depth charge dry hop filter, but its kind of pricey. Today I use a mesh steel filter that fits over my auto-siphon, so I don't like the idea of no filter.

I don't prop the fermenter up a few inches--I stick a shim under the spigot side that raises it maybe 5/8". But then, I'm not using 8 ounces in dry hopping! The thing you'll have to address is that if you do tilt the BMB back that much, you'll end up losing a fair amount of beer.

I don't get much in the way of trub through the tubing but that's partly because I flush the spigot to clear the (primarily) yeast trub.

Now, if you have an 8 ounce dry hop, yeah, you might overwhelm that spigot, and tipping the BMB a significant amount and letting it settle might be the only solution. The other possibility is to use hop bags to contain most of the hop trub.

What recipe are you doing that you need 8 ounces of dry hopping in a 5-gallon batch?
 
The thing you'll have to address is that if you do tilt the BMB back that much, you'll end up losing a fair amount of beer.

It works for me, I just un-tilt (or tilt to start with) after the liquid level has gone below the spigot and it stops flowing. One thing I love about the BMB is being able to see inside and know when to quit. I keep getting quite clear beer up to the point it's almost all emptied.
 
I don't prop the fermenter up a few inches--I stick a shim under the spigot side that raises it maybe 5/8". But then, I'm not using 8 ounces in dry hopping! The thing you'll have to address is that if you do tilt the BMB back that much, you'll end up losing a fair amount of beer.

I don't get much in the way of trub through the tubing but that's partly because I flush the spigot to clear the (primarily) yeast trub.

Now, if you have an 8 ounce dry hop, yeah, you might overwhelm that spigot, and tipping the BMB a significant amount and letting it settle might be the only solution. The other possibility is to use hop bags to contain most of the hop trub.

What recipe are you doing that you need 8 ounces of dry hopping in a 5-gallon batch?

Good point on losing some beer volume. I usually do a 6 oz dry hop for American IPA's and 6-8 oz for Northeast IPA's
 
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