Preventing boil over in automated system

Hello,

I am working on an automatic brewery that runs unattended until just before transfer to fermenter.

I thought of an way to prevent boil over and thought I would ask about it.

What if I take a lid for my boil kettle, drill small holes around the perimeter, cut a large duct size hole in the center, weld a stainless tube to the center hole forming a top-hat looking lid. Then run an exhaust fan to the pipe.

Air would be drawn in along the edges of the lid and pulled up the center pipe.

Foam would collect toward the center and maybe travel up the pipe a little, but not boil over.

Also, I was thinking out of curiosity if the draw of the fan would cause the foam to want to break earlier (sort of like when you pull the lid off of a boiling pasta pot, the foam breaks with the lower pressure).

What do you think?

I thought about this but not this method. I think this *could* work but you will need to dial down your heating in order for the foam to subside.

But, there must be bigger fish to fry in designing an automated brewery, no?. I would suggest a well oversized kettle and use fermcap. Obviously that would need to be dispensed if you are going end to end.
Alternatively optical sensing could be employed which would inhibit the heater. Or a resistance probe set, as the foam must have some conductivity that steam doesn't.

With my current setup I have a 20 gallon boil kettle for doing 10 gallon batches so it's pretty hard to boil over. I run the heating element 100% until I get to a rolling boil then cut it back to 70% duty cycle. In doing this I have observed it usually gets to a rolling boil about the same time the temp sensor gets to 212F.

The question here is what type of sensor can you use to determine when you reach a rolling boil to trigger turning the heat down. It might be as simple as using a temperature sensor along with a properly sized kettle.

So I am using keggles, so my boil kettle is fixed. I do want to push the limits on that volume so I wanted to solve the boil problem another way. I guess by adding my tube, I am in essence changing the volume.

I thought I would time the boil vs the temp to adjust the heater after a specified delay. I have thought about sensors but I have not found one that I really thought would work well.

Does anyone out there use a boil sensor?


Thanks

Run 100% to 210F, then something like 40% for 5 minutes, then 65% ongoing. That is about what I do when I'm at the wheel with a PID that doesn't switch auto/manual on its own.

You could use a set of stainless rods, space them and when contact is made, turn on a input to your controller. I thought of a mister like in the grocery store for produce, a fine spray of water will knock down the foam.

BrunDog said:

I would suggest a well oversized kettle and use fermcap.

Click to expand...

This is exactly what I do. I put in a few drops when I start fly sparging and I don't have to worry about it. I run my burner wide open and don't adjust once I hit boil, but for electric, you could just automatically adjust it when it hits boil temp.

I do similar to Bobby... My BCS is set to run my element in PID mode up to 210, then switch to duty cycle (manual mode) at 60% and boil from there. Only an occasional foam up unless using Fermcap.

Again, if you are building (built) an automated brewery, I would think this would be late on the list of items to design/build. I would bet even trimixdiver, who has arguably the most automated system on HBT, probably doesn't have this.

Speaking of, I don't think I have seen any updates on your system, TMD. Care to give us a status update?

So, for a little background.....

I have already designed the plumbing, the vessels, the heating and cooling system, the control system is in the works, the hop additions mechanism is being designed right now.

So far, I have some confidence in what is designed so far. The boil over concern I am still evaluating.

Can Fermcap be placed in the empty boil kettle at the start of the brew cycle? The boil kettle will not have liquids in it until sparge starts.

I can easily control the boil pod and % following and fixed schedule. I will probably do that for sure.

Thanks

Btw,

I will post a build thread when I get further.

I second most of what have already been said here.
The best way is to avoid boil over, by lowering power output until hot break is done.
I don't know enough about your system, or if you have considered it already, but you'd probably want some sort of failsafe in case of a stuck mash. That is some way of preventing boil up unless there is enough wort collected (and possibly an alarm).

My personal opinion is that, while I love automation, and is all for this kind of thing. You should never actually leave it unattended, unless you've built it to be very fail safe for the dangerous kind of failures.
A simple idea might be to put a temp sensor on the boil kettle (which you probably already have). You should be able to detect a nice temperature change when hot wort from lautering enter the tun.

I appreciate everyone's feedback. I do plan on having temperature sensors all over the place and I will have a float valve in the BK and MLT, so the heating elements won't fire unless liquid is detected. I also bought 5 wire valves that have feedback if the valves are fully open or closed.

The HLT will also have a float valve too. B

Fermcap-s is your best bet I have run wide open with 7.5g in an 8g pot.

Does fermcap just work if its in the BK during sparging? Or does it need to be added during the boil ive never thought about it...

If it just needs to be there your easiest solution is to just put a few drops in your bk so when you fill it it mixes all in and prevents the boil over.

Another method thats a bit hoaky, but depending on how your valves/hoses are hooked up you could "prime" your BK output hose with some fermcap and then when you reach boil switch your valves and recirc your BK for a few seconds to get the fermcap into your BK.

And after all that, your probably simplest solution is to take whatever solution your using to pour hops in at timed intervals,im guessing some sort of servo or actuator bowl holding hops that drops things in...and set up a 60 minute addition with some fermcap in it.

FuzzeWuzze said:

Does fermcap just work if its in the BK during sparging? Or does it need to be added during the boil ive never thought about it...

Click to expand...

You can add it any time. I usually add it shortly after I start sparging.

Awesome. I think I will do a combination of adjusting the heat down per Bobby-M's recommendation and start with Fermcap in the BK.

So is there any issue with Fermcap sitting out for hours before use? I plan to load dry ingredients and water in the HLT. Then have everything start possibly hours later. So the Fermcap would be in the BK for hours before wort touches it. Is that ok?

Ramdough said:

Awesome. I think I will do a combination of adjusting the heat down per Bobby-M's recommendation and start with Fermcap in the BK.

So is there any issue with Fermcap sitting out for hours before use? I plan to load dry ingredients and water in the HLT. Then have everything start possibly hours later. So the Fermcap would be in the BK for hours before wort touches it. Is that ok?

Click to expand...

Fermcap-s is just silicone in suspension. There shouldn't be any problem just putting a couple drops in your BK anytime before you get to boiling.

Duplicate

Thanks everyone for your help. I hope this problem is solved.

decoleur said:

Fermcap-s is your best bet I have run wide open with 7.5g in an 8g pot.

Click to expand...

If he is going to keep his 100% automation, he will have to invent and auto Fermcapq dispenser.

So, my intent is to set all of the ingredients prior to running the system, then not touch it until I am ready to transfer the wort to the fermentation chamber.


If I simply put Fermcap into the BK prior to starting, then I have met my goal.

Looking forward to seeing your design. In the meantime, what controller are you using? Also, how are you handling the "tricky" items such as sparge rate/matching, checking runnings gravity, hop and adjunct additions, etc?

BrunDog said:

Looking forward to seeing your design. In the meantime, what controller are you using? Also, how are you handling the "tricky" items such as sparge rate/matching, checking runnings gravity, hop and adjunct additions, etc?

Click to expand...

The controller will be a combination of a Raspberry Pi, an Arduino Mega, and a custom shield.

The custom shield will have on it an ESP8266 Wifi chip, a real time clock, 2x Ph/ORP sensor circuits, an Electrical Conductivity circuit, power supply circuitry, RTD sensor circuits, and headers for some cots relay boards. The board itself if designed for dual purpose..... It will also control my swimming pool (on a separate board and Arduino of course).

The RPI will run a web service that will both display brewing parameters, progress and allow me to load BeerXML files. I plan to use Beer Smith to create my BeerXML files. The RPI will run a broker service that will load the parameters into the Arduino over wifi.

The Arduino will run the actual brew day process and update the RPI for display. If the network were to fail, the Arduino would continue the last loaded profile. I will have the RPI and Arduino on UPS power.

Simple.... Right[emoji16]

Even though I will have a Ph sensor capability, my initial starting point will be to control all parameters by volumes and temperatures. I will calculate what volumes I need to reach my desired results using Beer Smith. For example, sparging will stop when the BK level hints a float switch. Later, I may evaluate other options, but in reality, I plan to hit a final volume. Also mashing will be by time and temperature as well. Maybe i will get the ph sensor going at one point, but that is a nice to have feature that was originally intended for my pool.

Sparge fill rate will be controlled with ball valves that are manually set to create resistance, then a float switch and actuated valves for the fine tuning.

The mash pump will have an output ball valve that will be set conservatively so as to prevent a stuck mash. It will basically run a bit slow.

I have not finalized the additions design. May be a carousel, maybe dumping hoppers, maybe flip top lid containers, maybe cascading waterfall chambers. I am not too worried about this one yet.

Holy h3ll, I hope you have a lot of spare time...

As for the additions, I would suggest you use servomotors. One for each addition.
Add a foot or so of thin square aluminium tubing (or something else light but rigid) to the rc and attach a container on the other end. Then just have the rc dump the container into the kettle.
The pro's of this is that rc's are cheap and easy to interface. You can add more if you need more additions. And not in the least, this keeps your hops away from the steam, which will otherwise be an issue you will need to handle, as steam will gunk stuff up.

Can't wait to see this come together! This will be an auspicious undertaking but surely we will all learn/benefit from it. Best of luck and get going!

The project actually is a team effort. We have most of the hardware. The RPI is running some of the services already.

Need the xml import and the web gui, then the RPI is done.

The schematics for each circuit is done, but need to be combined into one circuit card.

We are getting there slowly.

alphaomega said:

Holy h3ll, I hope you have a lot of spare time...

As for the additions, I would suggest you use servomotors. One for each addition.
Add a foot or so of thin square aluminium tubing (or something else light but rigid) to the rc and attach a container on the other end. Then just have the rc dump the container into the kettle.
The pro's of this is that rc's are cheap and easy to interface. You can add more if you need more additions. And not in the least, this keeps your hops away from the steam, which will otherwise be an issue you will need to handle, as steam will gunk stuff up.

Click to expand...

I thought of that option, combined with my top hat idea mentioned earlier to draw steam away from my hop additions machine. I actually have boxes of servos, but I have not finalized my plan. I want to be able to use both dry and wet additions if I want.

I have a dumb thought... What if you used a vacuum of some sort to remove any foam that is about to boil over? Perhaps a ring of small air intake holes. Foam comes up, gets drawn in. Use a gravity trap to capture. Elaborate but maybe worthwhile for fully automated configs.

Only question... Is this foam needed in the brew later (proteins for head retention, etc?). I don't really know but would assume removing a small amount would have minimal impact.

Again, fermcap much easier!

BrunDog said:

What if you used a vacuum of some sort to remove any foam that is about to boil over?

Click to expand...

A fan would be simpler. Ever blow on a boiling kettle? The foam drops right down. Does the same thing as fermcap by breaking the surface tension.

Vacuuming means you'll have some tubing that will need to be thoroughly cleaned or it will be molding in a day.

Solid points JonW. I just don't know that a fiercely rising boil will have its foam tamed by blowing on it. In any event, fermcap solves all ills.

You can of course build it with fans, or sprayers, or 'foam suckers' or whatever.
But you really don't have to. Just run at full power (after lautering) until you're a few degrees shy of boiling, then run at about half the power normally used (you know, the output needed to have a nice slow rolling boil) for about 15 minutes. This allows hot break to pass without any boil over. Then just up the power to normal and start the boil timer.
There is no need for fancy methods to have a 'controlled' boil over. Just don't allow it to boil over to start with.
Note that I don't mean this as criticism of your ideas, I'm all for new creative ways to do stuff. I'm just saying you don't have to complicate things unless you want to.

alphaomega said:

You can of course build it with fans, or sprayers, or 'foam suckers' or whatever.
But you really don't have to. Just run at full power (after lautering) until you're a few degrees shy of boiling, then run at about half the power normally used (you know, the output needed to have a nice slow rolling boil) for about 15 minutes. This allows hot break to pass without any boil over. Then just up the power to normal and start the boil timer.
There is no need for fancy methods to have a 'controlled' boil over. Just don't allow it to boil over to start with.
Note that I don't mean this as criticism of your ideas, I'm all for new creative ways to do stuff. I'm just saying you don't have to complicate things unless you want to.

Click to expand...

+1 for KISS

Right now, the simplest option appears to be to use Fermcap, then control the heater with some PWM profile that makes sense. That is what I am leaning towards.

I still will need an exhaust fan of some sort anyway, but that is tbd.

@Ramdough

It has been a while since you posted. If you moved forward with your project, would you mind posting an update?

I have designed a system very similar to what you have described. Difference is I am currently relying solely on an Arduino Mega. My UI is run from the Arduino for now (Pic attached). Plan to update to RPi later.

As designed, my system is meant to be hands free. Load the grain/boil adds, enter the recipe and it will stop when the wort is cooled in the BK. Couple of other points which might be of interest:
--Capture the heated water from cooling the BK boiled wort into the HLT
--Perform a 5 step mash
--Operate 3x heating elements from a single breaker

Anyway, I have purchased nearly all of the hardware for mine and hope to begin building late next week. I would be very interested to see what you have done. I will try to remember to start a new thread with my build once I get a little momentum.

The pic i uploaded is what I will call my "Feasibility" Build. I used a couple potentiometers to simulate analog signals from pressure sensors I will use to track water level in the vessels. Lights represent valves & pumps. Everything else was "Production" if you will. In simulations it worked GREAT! However, I am confident there will be a couple days/weeks of debugging once I get this built.

@bheinecke. I had a little setback..... I sold my house and moved all of my brew stuff into storage. On a brighter side, my new house will be pre-wired and vented for my brewery. I also plan to run my taps through the wall into my planned outdoor kitchen. Do you have a build thread? If so, post it here so I can see it. Look good so far.