In Bag Circulator

[Owly055]

Here is a rough drawing of an in/bag circulation system for BIAB. The purpose is to allow you to dough in the night before brew day at tap water temp, and use a timer to start your mash just as you would your morning coffee so the mash is done when you get up. It is to be used with a hot plate and any level of control suitable. For example the minimum level of control would be to set the hot plate at a specific level, knowing how long it will take to reach mash out temp and just do a slow heat. The next level would be a wake up alarm based on temp. The next level would be fast heat to a specific mash temp using a PID controller. The next level would be to have a separate kettle that would heat to strike temp, and a valve that would drain the strike water into the mash kettle, using the circulator to mix the mash, etc.

The impeller, not shown in detail would initially be nothing more than a flat disk with several slots cut into it and tabs turned up.

The motor could be any number of possible motors. The cheapest might be an electric mixer, or a harbor freight variable speed drill. Variable speed would be desirable. There are numerous variable speed motors for various applications that could be cannibalized or simply borrowed for this.

 

[Owly055]

This afternoon I will be doing some machining to make my prototype in bag circulator.

I've got a motor and speed controller.... I had them laying around already. It's the drive motor for a Linde Mig welder, and a KBIC 90 volt DC variable speed controller.

I've got my tube.... the stainless steel housing from a junk submersible pump... 3.25 ID

My shaft is a piece of 6061 T6 aluminum... far larger than I really needed.... at 1.25" diameter. I'll drill one end to fit on the motor, and turn the other to fit inside my impeller, and turn a bunch of the surplus material off.

My temporary impeller is a "found item" ...... In playing with building a stir plate, I decided to demolish a computer power supply fan, and attempt to "liberate" the actual fan blade. It turned out to be fairly simple, and has an inside bore of about an inch and an eighth. I'll turn the aluminum shaft down to where the plastic fan will slip on.

Considering the fact that the mash is only around 152 deg, the fan should stand up, and should impel the mash downward in the tube while turning a pretty low speed. The mig motor is designed for low speed........ with it's integrated gear box.

The main purpose of this is to maintain a uniform temperature by circulating the mash down in the center and up around the edges of the pot creating a torroidal flow. A thermocouple mounted to the tube will take temp readings, and ultimately be connected to a hot plate via a PID controller. This will allow me to do a BIAB mash that will start on a timer.




H.W.

 

[JINKS]

Sounds interesting.

 

[Owly055]

It should be noted that I do NOT intend to use the bottom bearing as illustrated....


H.W.

 

[aamcle]

I built a stirred BIAB



Yes it kept the temperature constant and yes it was a waste of time. An insulated vessel and/or recirculating will hold temperature and they are both less trouble.
I'm not an efficiency hunter but I've got about 86% mash efficiency on my last two recirculating BIAB batches.

The motor and paddle are now both in the junk draw and I'm not expecting to get them out but then I wasn't trying to get it to start mashing before breakfast. Good idea that😷

Aamcle.

 

[Owly055]

I built a stirred BIAB



Yes it kept the temperature constant and yes it was a waste of time. An insulated vessel and/or recirculating will hold temperature and they are both less trouble.
I'm not an efficiency hunter but I've got about 86% mash efficiency on my last two recirculating BIAB batches.

The motor and paddle are now both in the junk draw and I'm not expecting to get them out but then I wasn't trying to get it to start mashing before breakfast. Good idea that😷

Aamcle.

Thanks for the photo.... there truly is nothing new under the sun..... My concern with your setup is snagging the bag.... Looks like it's a fairly wide paddle system... A different way to accomplish the same end.

My system IS a recirculating system..... just not through the bag. I don't like the issues I have had with recirculating through the bag ....... slow draining of the bag which ends up partially clogged. It didn't work well for me. This is an attempt to rewrite the book on BIAB RIMS. I too have things in the junk drawer........ including my recirculation system for BIAB RIMS. It was too much trouble.......... This has the additional advantage of easy cleaning.

What was your drive motor setup??


H.W.

 

[aamcle]

The motor is a 2 speed Ford windscreen wiper motor, I don't know it it's in that picture but I had a SS mesh cylinder to stop the impeller fouling the bag.

My recirculating Biab has an inner basket that holds the bag, its all very easy to clean and it works pretty well.




Atb. Aamcle

 

[Owly055]

Thanks for the photos..... Basically I'll be doing exactly the same thing you are..... recirculating the mash. The only difference is that my pump will be right in the mash, instead of having a tapped kettle, an external pump, hoses, and a return system, everything is incorporated into a single component. The circulation is reversed..... downward to the bottom of the kettle instead of from the bottom and back up.

My brewing is in 2.5 gallon batches, and my brew kettle is a Walmart stainless steel stock pot with a laminated bottom. It works well for my operation except for the "thermal flywheel" effect of the thick laminated bottom. I have no intention for my scale of brewing to use a tapped kettle, nor do I intend ever to upgrade to larger batch sizes... at least not where I currently live. 5 gallon and larger brewing is a different ball game..... Pumps and valves, tapped kettles, propane burners, etc all fit with this kind of brewing. With that in mind, a system like yours makes more sense than what I am proposing. This is a small brewer's system. For you it would mean one more piece of equipment.... for me it means less. I don't need a pump for any purpose at this scale. A pump leads to plate or counterflow chillers, filter systems, hop backs, whirlpool sytems......... All useful pieces of equipment....... I would love to have the benefit of a hopback...but am not willing to accept the complexity it involves. I brew on the kitchen stove... more equipment means more things to clean up, store, get out for brewing.... and all each week.


H.W.

 

[aamcle]

Its an interesting system you're building, are you going to fit a mesh (like the GrainFather) to stop the grain following back into top of the pump tube? I brew 23 litres and I'm moving to 10 litres, there is usually only me drinking so a full batch is too much.

If I understand it the grain will be in the bag, strike water will be added then the pump started. The pump then mashes in getting rid of all dough balls, how is that going to work in the corners were the walls meet the base?
Are you planning to run the recirculator/pump as fast as a hand held stick blender?

I'm interested hear how you get on with this build please keep posting.

Aamcle

 

[Owly055]

I don't need a screen because I'm using reverse circulation.... Drawing from near the surface of the wort through openings in the tube, pushing the wort down. This means that because of the location of the suction openings, the bag should not be drawn into them for two reasons. One is that there will be a large area of openings relative to the flow, and the other is that there is minimal slack in the bag near the top of the kettle. At the bottom of the pipe, it is pushing down against the bag instead of drawing up toward the bag.

The strike water will be added the kettle as tap water, and the grain then added and mixed the night before, so there will be no dough balls...... or at least that is my intent. I will be brewing tomorrow, and as a test, I'm going to dough in tonight, go to bed, and start brewing in the morning just to see if this is feasible. In the case that it is not, there is always the possibility of having a grain hopper that slow feeds.... just one more piece of equipment to build.

Note that the pico brew has the grain in a hopper dry, and apparently mixes by circulation.....

The devil is in the details of course.... it may not be workable in this simple form.... If it proves impractical, I will scrap the idea as I have many others over the years and move on to "plan B"

Plan B does exist, and uses technology that has been proven to work, but in a simplified form.

H.W.

Its an interesting system you're building, are you going to fit a mesh (like the GrainFather) to stop the grain following back into top of the pump tube? I brew 23 litres and I'm moving to 10 litres, there is usually only me drinking so a full batch is too much.

If I understand it the grain will be in the bag, strike water will be added then the pump started. The pump then mashes in getting rid of all dough balls, how is that going to work in the corners were the walls meet the base?
Are you planning to run the recirculator/pump as fast as a hand held stick blender?

I'm interested hear how you get on with this build please keep posting.

Aamcle

 

[aamcle]

I've had a problem that might be relevant, wort boiling under the bag. I had the temperature probe in the bag but the bottom of the bag formed a thermal barrier and local overheating occurred.

Its just something to keep an eye on it may well be no issue in your system.

Good Luck for tomorrow.

Aamcle

 

[Owly055]

I've had a problem that might be relevant, wort boiling under the bag. I had the temperature probe in the bag but the bottom of the bag formed a thermal barrier and local overheating occurred.

Its just something to keep an eye on it may well be no issue in your system.

Good Luck for tomorrow.

Aamcle

I've fought that problem with BIAB on the stovetop.... it requires a significant amount of stirring to keep things under control. With my 20 minute to 30 minute mash it's not a big deal.... Stovetop isn't practical for an hour mash... the best solution would probably be a "heat stick". I'm thinking that the fairly strong downward current of mash in the middle of the bag should alleviate this somewhat.... hence the torroidal flow concept. It should also keep the grain in suspension.

The brew bag is a mixed blessing...... Ultimately I want to move to a bagless system, but that will require a pump and a grain tube, and would be a reverse circulation system like the Braumeister with the idea that the flow of wort would keep the grain in suspension, possibly cycling off and on ... Pumping up through the grain bed and over the top back into the kettle, cycling off to drain back down through the pump, and repeat. But that's another project for another year.......... There is always a plan in the skunk works for me. When I stop dreaming things up, will be when they put me in a box.


H.W.

 

[aamcle]

I built BM type, http://www.frankenbrew.co.uk/frankenbrew-lives/ I find that although it works well I'm not that happy with it.


I don't like having the pump trapped underneath where its hard to clean, it produces clear wort and control is easy.
The control box is simple, a ramp step PID , a repeating cycle timer and a PWM I'm not sure what puts me off it other than the pump location. I've only used it once, mine is too small for a 23 litre batch but too big for a 10 litre one it's not very flexible.

I'd prefer a GrainFather type as there are less restrictions on volume, gravity and the bits are easier to clean.


Atb. Aamcle

 

[Owly055]

I built BM type, http://www.frankenbrew.co.uk/frankenbrew-lives/ I find that although it works well I'm not that happy with it.


I don't like having the pump trapped underneath where its hard to clean, it produces clear wort and control is easy.
The control box is simple, a ramp step PID , a repeating cycle timer and a PWM I'm not sure what puts me off it other than the pump location. I've only used it once, mine is too small for a 23 litre batch but too big for a 10 litre one it's not very flexible.

I'd prefer a GrainFather type as there are less restrictions on volume, gravity and the bits are easier to clean.


Atb. Aamcle

Nice build!!!.... a Braumeister clone more or less from what I can see.... I'm having problems visualizing exactly how things work. I presume that the stem sticking down off center on the inner pot (grain tube) mates with one of the fittings in the brew kettle. I also would presume that there is a bottom screen of some sort that is not shown. A hidden pump is "elegant" but as you say a pain to clean.

The design I have in mind is quite different in that the grain tube would be completely above the brew kettle and possibly off to the side, and the supply of wort would be pumped up to it, and would return from above the top screen. You would not lift it out, as it would already be out, nor would it be dripping with wort... the wort would be in the kettle and the hoses.... and the grain tube when it's running. It would sit on the burner the whole time, but the burner would only be on during the boil. A RIMS type heating system would be operated during the mash. When you switched from mash to boil, the pump would be shut off and a selector valve would drain the wort into the kettle bypassing the pump. runnings from the grain tube would continue to drip into the brew kettle as long as you allowed it. You would close the kettle valve, and disconnect the line at the selector valve which would be above the kettle, and drain it into something and pour it in the kettle. You'd probably want a drain valve right at the coupler coming from your kettle valve to keep things neat.... Putting everything on a decent grade would make life easier. I'd really like a shaft drive pump submerged right in the wort, and a kettle with no ports at all.

The only design feature in common with the Braumeister is reverse circulation through a grain tube.... it won't be the elegant compact design with a pot inside a pot, but can be stored that way more or less. Of course it will be half the size... a 2.5 gallon setup instead of a 5 gallon.

H.W.

 

[aamcle]

Oh an upgrade on a BrewEasy 😷 I've supposed to be building something like that but I've run into a wall.
I contacted Blichman apparently holding temp isn't an issue, I'd still insulate everything I could, so you may not need the rims.
I had been considering using the constant head system from the GF.
What do you have against taking things through the side of your boil pot?

Atb. Aamcle

 

[Owly055]

Oh an upgrade on a BrewEasy 😷 I've supposed to be building something like that but I've run into a wall.
I contacted Blichman apparently holding temp isn't an issue, I'd still insulate everything I could, so you may not need the rims.
I had been considering using the constant head system from the GF.
What do you have against taking things through the side of your boil pot?

Atb. Aamcle

I'm brewing 2.5 gallon quantity, so there is really no reason for a tap on the boil kettle. The tap, and valve and coupler stick out a considerable distance which changes the storage and cleaning situation....I can't nest it with other containers as I do now...it sits in as larger kettle when not in use. It also would not fit in my kitchen sink...... I brew in the kitchen.... It's generally just an awkward situation as far as I'm concerned. "Your mileage may vary".

When I was experimenting with BIAB recirculation (through the bag), I built a very successful "suck start" system, which essentially was a siphon using rigid copper pipe to feed my pump..... I would suck on the recirculation hose.... which was on the pressure side of the pump to draw the wort through the pump. As the pump was below well below water level, the pump held it's prime and worked great. This was ONLY for mashing. I caught a lot of mindless flack over it here.... sanitation comments ...... which I don't understand as you are going to boil afterward anyway.....and comments about getting a mouthful of scalding wort.... also a non issue as it is being used with 150 deg water... or less. To me it's a far better solution all things considered than the conventional ported kettle......... at least for my use.

H.W.