Boil kettle condenser - no overhead ventilation needed

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Well, initial live brew results coming back....

First note: Much drier brew space (my garage). Normally it would be a sauna. So from that perspective, it achieved its goal.

Second note: I needed to turn the boil power down. I mean way down. I mean half!! That’s a nice power savings, though it wouldn’t really translate to much $.

Third note: Boil off rate is greatly reduced. As in half also. I expected to boil off a gallon and ended up boiling off... well, you know the math.

Fourth note: With the above results, we might conclude that the dms and other volatiles were not appropriately carried away. Only time will tell with this beer I did. I will say this though... I tasted the ejected water and it tasted and smelled sweet and corn-like. I think that’s promising but of course not scientific at all. And it had no hop influence because I did a pantry-sweep beer and all I had were summit hops - since they are high Alpha, I only used 0.2 oz. at 20 mins and the remainder at 5.

One thing I will note is some steam does escape out of the flush tube, when that is blocked off some steam begins to escape from under the lid. More to come on that as I add a longer drain but I don’t think it means a whole lot at this point.

Final result once this beer ferments! See my personal build thread for the other experiment I ran with this beer and the whacky ingredient list (that experiment failed, btw).
 
Early results sound promising!

What size heating element do you have in the boil kettle? Sounds like you could downsize that with this setup.
 
Second note: I needed to turn the boil power down. I mean way down. I mean half!! That’s a nice power savings, though it wouldn’t really translate to much $.

Third note: Boil off rate is greatly reduced. As in half also. I expected to boil off a gallon and ended up boiling off... well, you know the math.

Fourth note: With the above results, we might conclude that the dms and other volatiles were not appropriately carried away.

Your reduction in power setting mirrors my own. The reduction in evaporation needs to be accounted and planned for. It will take time to figure out what the new starting wort volume needs to be.

Assuming that you boiled an hour, its likely that all the DMS was volatilized, but I'm not sure if it made it out of the 'sealed' kettle. That's why I'm opening my kettle for the final minutes to assure that DMS is expelled.
 
Assuming that you boiled an hour, its likely that all the DMS was volatilized, but I'm not sure if it made it out of the 'sealed' kettle. That's why I'm opening my kettle for the final minutes to assure that DMS is expelled.

But the condenser causes a pressure drop, so the DMS should be more easily evaporated. Some breweries that have installed condensers have been able to shorten their boil. It's mentioned in the LBNL "Energy Efficiency Improvement and Cost Saving Opportunities for Breweries" report.
 
But the condenser causes a pressure drop, so the DMS should be more easily evaporated. Some breweries that have installed condensers have been able to shorten their boil. It's mentioned in the LBNL "Energy Efficiency Improvement and Cost Saving Opportunities for Breweries" report.

This result is odd since DMS boils at 99F. A reduction in pressure within a kettle would only serve to evaporate water more effectively, not DMS. In addition, unless the kettle is sealed, its not going to be under a vacuum.

This information doesn't seem to be accurate, at first glance.
 
The quoted document can be found here: https://www.energystar.gov/sites/default/files/buildings/tools/LBNL-50934.pdf

Page 23 discusses DMS, though this is a very different application (steam injection & ejection), so I am not sure this is an apples:apples evaluation.

There may be a minor pressure drop, but as Martin notes DMS is boiled off at a low temperature, so as long as it is captured in the steam, which gets flushed out the condenser drain, we should be good. Of course it will take more time. I will do a lager to see if DMS presents any problem. I know that wont be scientific, but its what I can do, unless someone knows offhand a lab which can test wort samples, in which case I would boil some via open lid and some via the spray condenser.
 
This result is odd since DMS boils at 99F. A reduction in pressure within a kettle would only serve to evaporate water more effectively, not DMS. In addition, unless the kettle is sealed, its not going to be under a vacuum.

...

What's special about DMS that it wouldn't boil at lower temps at reduced pressure?

Brew on :mug:
 
What's special about DMS that it wouldn't boil at lower temps at reduced pressure?

Brew on :mug:

I think this just implies that since the boiling temperature of DMS is so much lower than wort, the additional bonus due to pressure isn’t going to make a difference.
 
I think this just implies that since the boiling temperature of DMS is so much lower than wort, the additional bonus due to pressure isn’t going to make a difference.

That is correct. In addition, I've been researching DMS for an article I'm authoring and there is a journal article by Wilson and Booer in which they looked at boil vigor (as evidenced by evaporation rate) and they found that the DMS reduction didn't change in proportion to the evaporation increase. That's why I imply that the change in DMS content due to pressure reduction won't be that significant.
 
This result is odd since DMS boils at 99F. A reduction in pressure within a kettle would only serve to evaporate water more effectively, not DMS. In addition, unless the kettle is sealed, its not going to be under a vacuum.

This information doesn't seem to be accurate, at first glance.

I seems I misread this section of the report - "savings resulted from shortening the wort heating time". I took that to mean there was a shorter boil, but it's referring to the fact that the wort is pre-heated by the hot condensate from the kettle.

The more significant effect of lower pressure systems is that the rate of decomposition of SMM will decrease rapidly with a drop in boil temperature - more than halved at 95C and reduced 96% at 80C (0.85bar).

To overcome this the Interbrew dynamic low pressure systems alternates between low and high pressure. At high pressure SMM is quickly decomposed and good hot break occurs. The pressure is dropped instantaneously. Small steam bubbles form throughout the boil volume giving a very large steam/liquid interface. This flushes the DMS.
 
...

The more significant effect of lower pressure systems is that the rate of decomposition of SMM will decrease rapidly with a drop in boil temperature - more than halved at 95C and reduced 96% at 80C (0.85bar).

...

Interesting. I was thinking, after reading about the low BP of DMS, that it should be removed from the wort very quickly, since wort boils at ~60°C higher than DMS. That would imply that the rate of DMS removal would be controlled by the rate of it's formation from SMM, and your post confirms that in my mind. I expected the decomp rate of SMM to be temp dependent, but the data you reference, says it drops off twice as fast as the "rule of thumb" for organic reactions (rates double or halve for a 10°C temp change.) I found this to be surprising. This might be something for folks who brew at high altitudes to worry about.

Brew on :mug:
 
Valid points. But do you want to break the news to the brewers in Denver? They think they are the craft capital of the world - this could devastate them! Haha, I am just having fun!! 🤣

I'm sure the craft brewers can figure out what they need in the way of boil times to avoid DMS, even if they don't understand the science behind it. It's more of a concern on the homebrew level if someone in Denver hears about someone doing short boils, and they try to duplicate it with poor results.

Brew on :mug:
 
Interestingly, for those super water conscious, you could automate the water flow rate with a proportional valve (very small Cv range), using the flush exit temperature for guidance. I am probably going to upgrade to the 9 gph and call it a day, but it’s an option.

Could you drop a few frozen water bottles in your drain bucket along with a small pond pump and then drive the spray with recirculated water?
 
Yes, but the pump used would need to be able to create the pressure. Also understand the amount of heat getting pulled out. It would take more than a few frozen water bottles.

If water usage were a real concern, I would use a radiator / fan to circulate the water through.
 
Another alternative might be to just capture the water and let it cool off in between brew days; at 9 gph, you will only need to store about 10 gallons. Run it through the condenser, collect the water, let it cool off for a few days, then repeat.

You are wasting the heat that way though. I think the “greenest” solution is to reuse the hot water for cleanup. That way, you are making use of both the water and heat.
 
Another alternative might be to just capture the water and let it cool off in between brew days; at 9 gph, you will only need to store about 10 gallons. Run it through the condenser, collect the water, let it cool off for a few days, then repeat.

You are wasting the heat that way though. I think the “greenest” solution is to reuse the hot water for cleanup. That way, you are making use of both the water and heat.

That sounds like a great way to feed microorganisms. It's 9 gallons.... put it down the drain.
 
Ya totally agree. The water could be collected, let cooled, then re-used. That said, I don’t think this water is all that clean. It will have the boiled-off volatiles in it. I think you could recirculate it a couple of times but at some point it will have to be dumped. Or you could use it for first-round cleaning.

For me, and as noted above, 9 gallons is not a huge issue. I am sure I dump that much and more chilling.
 
This is a great idea brundog, I am in Florida as well (st pete) and have slowly collecting all the pieces my an electric system but didn’t know what I was going to do with the exhaust as cutting holes in my garage wall would not make the Wife very happy!

Do you have that parts list? I would be interested in trying to put this system together to start testing myself!
 
Any reason at a homebrew scale we couldn't just make a port in the kettle top, and run the steam through something like an aluminum transmission cooler with a PC fan attached, and basically air-cool it, and not deal with water-cooling the steam? The little waterwise water purifiers are kinda like that and they are pretty effective at eliminating steam.
 
Thank you for doing this experiment. I hope that it works out well with a pale lager. I would think that if the condenser created enough air flow then it would suck the DMS out before it could condensate on the lid.

However, it is not just cooling of the steam that is creating the airflow. I used to be a firefighter and we sometimes used hydraulic ventilation. We would set our fog nozzle to a 45 degree pattern and put it outside of an open window. The water flow would such the smoke out of the room. Your water spray pattern in the picture looks right on target. Well done sir.
 
I’m wondering if some of the condensing assemblies that are made for all in one systems for distilling would work for eliminating steam during the boil. I have no interest in distilling, but am thinking of getting a grainfather or the Brewha BIAC. Would something like this do the same thing described in this thread?
https://brewhaequipment.com/collections/extras/products/condensing-assembly
 
Any reason at a homebrew scale we couldn't just make a port in the kettle top, and run the steam through something like an aluminum transmission cooler with a PC fan attached, and basically air-cool it, and not deal with water-cooling the steam? The little waterwise water purifiers are kinda like that and they are pretty effective at eliminating steam.



I think you can use a radiator but it will need to be sized to draw away enough heat. There is a lot of latent heat that needs be pulled out to convert steam to liquid. I would think the airflow restriction of an air-air heat exchanger might require a fan or air pump to pull the air/steam through also.
 
I think you can use a radiator but it will need to be sized to draw away enough heat. There is a lot of latent heat that needs be pulled out to convert steam to liquid. I would think the airflow restriction of an air-air heat exchanger might require a fan or air pump to pull the air/steam through also.

Yes, thats what I was thinking. I have a waterwise and I may just try to hook up its condenser to a ported kettle lid and see what happens. Granted, a watewise is a 1G system, but I should be able to tell from a test if I can hook it up. The water in that system goes in at boiling and comes out a little over room temp. It will definitely be worth the test.

It never occurred to me before this forum topic to try to condense the steam. I got kicked out of the kitchen over too much steam output so if I could reduce it, I can brew inside again. Beats brewing outside in the rainy season.
 
Thank you for doing this experiment. I hope that it works out well with a pale lager. I would think that if the condenser created enough air flow then it would suck the DMS out before it could condensate on the lid.

However, it is not just cooling of the steam that is creating the airflow. I used to be a firefighter and we sometimes used hydraulic ventilation. We would set our fog nozzle to a 45 degree pattern and put it outside of an open window. The water flow would such the smoke out of the room. Your water spray pattern in the picture looks right on target. Well done sir.



The liquid running out of the drain is very hot. That heat comes from the steam. So yes, the steam and volatiles in are are being drawn out. The percentage is likely fairly high, because the kettle lid cannot transfer off enough heat to condense large volumes of the steam. You could insulate the lid if that were a real concern.

As far as the hydraulic ventilation - there is probably some function of it occurring, though the drain is a fairly small diameter. A larger one would be better in this regard. Might be worthwhile to upgrade to a bigger nipple and tube.
 
The liquid running out of the drain is very hot. That heat comes from the steam. So yes, the steam and volatiles in are are being drawn out. The percentage is likely fairly high, because the kettle lid cannot transfer off enough heat to condense large volumes of the steam. You could insulate the lid if that were a real concern.

As far as the hydraulic ventilation - there is probably some function of it occurring, though the drain is a fairly small diameter. A larger one would be better in this regard. Might be worthwhile to upgrade to a bigger nipple and tube.

It would be worth a test. The water would still cool the steam to its condensation point, but it would create overall more airflow.
 
I am very interested in your progress with this. I love seeing people push the boundaries of homebrewing. Is there a way to get your beer analyzed? Do you know anyone who runs GC/MS or HPLC/MS for a living? My initial concern was what you mentioned, venting off the many precursors to unwanted flavors, DMS being the result of just one possibility.

One solution would be to keep a vigorous boil with no condensation system in the beginning perhaps?

Well done on the work and thank you for sharing!
 
I agree. One of the topics that cam up in discussion with a friend yesterday was something we were both thinking about independently... that mist atomization is as important or more important. I really need to try to qualify the atomization that occurs with the 6 gph vs the 9 gph sprayer. My anecdotal feeling is the 6 is finer. This may be related to the nozzle size and pressure used. Better performance might be better with a pump to elevate the pressure prior to being sprayed.

This may be chasing an unnecessary problem, but certainly more tests to learn and make this as effective as possible are in order.
 
I was also thinking about this the other day concerning how it could be incorporated into a lid.
Brundog, was there some specific reason you put the port in the side of the kettle versus the lid? I like the simplicity of your design, but I couldn't sacrifice that 2" headroom in my BK without taking a hit in my batch size.
 
Great question. I put it in the side because I do take the lid on and off often enough and felt the hardware built into it would make it cumbersome. My kettle stays mounted as I CIP so this made logical sense for me. But higher is always better for both kettle volume and steam capture.

One side benefit (pun intended) of putting it on the kettle is this design eliminates the chance of a boil-over. Should one happen, that foaming wort will go through the drain! I personally use fermcap religiously so it’s never an issue, but it’s a safety I guess.

Putting it on the side made part selection easy, as a 2” TC tee is easy to get. A sweeping 180 tube is harder to come by and likely much more expensive.

All that said, no reason you couldn’t easily put something like this on the lid.
 
Sorry I'm sure you're getting bombarded with questions since this came out in that newsletter but any reason why you don't just use a normal lid? Was it to just see inside for the experiment?
 
Electric brewing pioneers like Kal came up with an overhead ventilation system consisting of a hood and fan which generally work well.
I can't take credit for that... ;) That goes to whomever invented condensate hoods for use in restaurants (usually over dish washer sinks) or even just simple stove hoods.

Kal
 
Sorry I'm sure you're getting bombarded with questions since this came out in that newsletter but any reason why you don't just use a normal lid? Was it to just see inside for the experiment?

I only used plastic wrap for the test so that I could "see" the steam escaping (it didn't work). A lid would be normally used.
 
I only used plastic wrap for the test so that I could "see" the steam escaping (it didn't work). A lid would be normally used.

That's what I figured. I'm definitely going to be implementing this in my home brewery as I just moved and there is no convenient spot for a high powered ventilation hood without significant remodel/work.
 
I would be curious to see how this preforms in reducing the DMS. I think a good test would be to brew a Helles and see if you can taste cooked corn. Again awesome work Brundog!
 
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