Water(less) Wort Chiller

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Mountainbeers

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So I've been getting ready to go AG soon and I am amazed at the amount of water these chillers go through.

Yea yea I know what you're going to say..."Recycle your water!"..."Recirculate your water!" Well I'm willing to do that but only if I can't find an easier solution first.

I started trying to think of a design for a chiller using ice. The problem with ice baths now are that a) they melt too fast and b) the heat (energy) isn't taken away like it is in water in say an IC so it takes too long.

Now for the boring part. Hang in there.

The general heat transfer formula is:

1/UA = 1/h1*A1 + (dx/KA) + 1/h2*A2

U = the overall heat transfer coefficient (w/m^2k)
A = contact area (m^2)
k = thermal conductivity of material (w/mk)
h = individual convection heat transfer coefficient for each fluid (w/m^2k) (this depends on the type of fluid and the velocity at which it is moving)
dx = wall thickness (m)

So in general, in order to increase your heat transfer you want to:

1) Increase the amount of contact between the fluids. (A)
2) Decrease the thickness of your copper wall. (dx)
3) Increase the speed at which the fluids move by each other. (h)
4) Increase convection coeff. (h)

With the below design you would be keeping the same k and dx because you are using copper tubing. The only common material with a higher coeff. than copper is silver. And this obviously isn't practical. Ice would fill the cavity (which would be closed off on the ends) and melt down through the holes. The ice conducts heat about 4 times more than water.

Has anybody tried anything like this?

WortChiller.bmp
 
I'm not quite getting what that object is supposed to be. Is it a U-shaped copper tank? There really isn't a way to get enough ice directly into a batch and have it work well. Pol recently worked out how much total ice you need in a closed system and I think it was something like 40 pounds. Search for closed chilling.

Think of it this way, most water companies charge less than a 1/2 penny per gallon. Even if you used 100 gallons to chill, that's a whole 50 cents.
 
Yeah, I'm a bit puzzled by your 3D model screenshot. A couple of 2-D sketches, labeled, would probably convey your concept a lot more clearly.
 
It looks like this is a rendering of a square copper bucket with the sides cut off. The ice is put in the bucket and allowed to drain as it melts. I am guessing the bucket is square for benefit of surface area to volume ratio. I think this an interesting idea that could be on the right track to having a water(less) wort chiller, but it looks like there may be problems found in draining the ice - where does it drain to - and you will need a pretty big kettle with a lot of freeboard to submerge this thing.

I like the large surface area, small chilling mass idea though. I imagine a copper cube that will fit a bag of ice and a bunch of copper tentacles extending from the ice chamber out into the wort. Then you'd need to replace the ice when it melts throughout the chill. With enough brainstorming maybe you'd stumble on something simple enough to actually incorporate into your brewery.
 
OK so I guess I didn't explain well. It's just a container of any type of material that is enclosed but the sides are cut off in the picture so you can see inside. The tube going through it is copper. The container is filled with water and frozen into a block of ice. Wort is siphoned/pumped through the tube.

I wasn't worried about the cost of the water as much as the environmental effects. The last two summers here in NC we have been on water restrictions because of drought. I just hate waste in any form.
 
Right I think no-chill is the most environmentally friendly way to get wort to room temp. For fast cooling a regular chiller is next best with re-using the water for another application since it is still clean. I do laundry with my chiller water and also save it for clean-up.
 
How much energy will you use to freeze that much ice?

Guess it just depends how much I need. I don't know how big the container would be yet.

1 gal of water is 3.79 kg
spec. heat cap. of water is 4186 j/kg-K

What does water come out of the tap at? 60 F? That's 15.5 C.

Q = m*c*deltaT

Q = (3.79)(4186)(15.5) = 245,906.57 J/gal

245,906.57 J * 2.7778×10^−7 = .0683 kw-H

Average cost of electricity in April 2009 $0.12/kw-H

$0.0082/gallon of frozen water.

You better come back to this thread after all that work haha.

:mug:
 
Guess it just depends how much I need. I don't know how big the container would be yet.

1 gal of water is 3.79 kg
spec. heat cap. of water is 4186 j/kg-K

What does water come out of the tap at? 60 F? That's 15.5 C.

Q = m*c*deltaT

:mug:

What I remember from my Heat Transfer Classes in College is that Q= U*A*Delta T log mean. If your looking for a better heat transfer you'd want to look at shell and tube heat exchangers or plate and frame. Really the key is to maintain a high temperature driving force to ensure heat transfer.

CA
 
To save water, a plate and frame heat exchanger can be used with glycol (or H2O) in a chiller, that way the cooling liquid can be reused.
 
While this is out of my league.. Maybe something like the coils of an AC unit with the spines wrapped around the copper tubing? To dissipate the heat more thoroughly through the ice block? Like a spinefin IC coil frozen in a block of ice?
 
The thing about having so much copper touching the ice is that it will melt in a matter of minutes. I'm going to just have to do some test runs.
 
I wasn't worried about the cost of the water as much as the environmental effects.

FYI, water is not consumed by the beer-making process. Its just moved from a pipe to the sewer, or grass, etc. The environment doesn't see a net loss.

Also, if you are in WV and you want to conserve water, now is a good time to create a cistern of water behind your house. I would guess it would be very cold at this time of year, and you could use if for chilling your beer. Additionally, you would return the water to the cistern and there would be a net zero use. I do this... I have a 17000 gallon cistern behind my house that I use for cooling. My pool.
 
Environmental impacts are tough to calculate. You have to know how the electricity was produced to freeze the water to make the ice. I rarely ever let my chilling water go down the driveway. It's used for cleanup first and any leftover goes in my washing machine or into the kitchen sink for dish washing. In the summer when I'm growing hops, I let the water cool a bit in buckets and water plants later.
 
The problem I see with your idea is the lack of contact with the ice. The one point of contact will melt leaving a grove in the ice block that will no longer be touching the tube because the ice around it is still holding it up.
If you are worried about water use then go to a plate chiller and use chilled glycol and pointed out earlier.
 
I agree with passedpawn so far as it can be applied to those of us that have well water. However, one often forgot aspect of your domestic tap water is the millions of dollars we spend on water treatment and the environmental impacts of the chemicals used in those processes. Not to mention the cost of the wastewater treatment facility and related chemical and energy consumption. If you are wasting water from the pipe to the drain, that has huge impacts beyond the "wasted" gallon.
 
I probably spend 4x more time building stuff than brewing and applaud your approach!!-I tried freezing a coil in a bucket and then trickling wort thru it and it worked well but it will need some agitation to circulate the heat away from the tube and to maximize the effect from melting.It is easier for me to get water than huge amounts of ice so a combo worked best.I found putting the post chiller coil in a bath with water and ice and keeping the ice water melt in the bucket and adding a trickle on tap water from a garden hose with outlet in bottom of bucket (so warmest water on top will flow over top and out) to work VERY well and was simpler.."waterless" is not really what U have-it is reduced water
 
Use a primary and secondary chiller. The primary could be a coil dropped into the wort which has another coil placed in a bucket of ice water. The down side is that you need a pump to transfer the fluid in the primary and you still need to keep the ice water agitated. But it would keep your water "waste" to a minimum and depending on your coils should drop the wort temp fairly quickly.

I'll be building this sometime in the near future, I'll let you know how it turns out.
 
My guess (based on training in process design) is that the downward melting of ice will not really contribute much. Your statement of the fact that ice conducts heat much better is of little value when you consider that the majority of heat transfer in a moderate Re flow (unless your plates are very close, there will be a fairly high Reynolds Number) is dominated by convection. That said, convection in water is greater than conduction in ice.

Your concept would benefit from maximizing surface area and using a ice and salt solution bath. The salt will depress the freezing point so you can achieve something in the area of -15C and give you a very good driving force. Rapid circulation in your media will ensure uniform cooling as well.

Your volume of ice-salt water solution is quite easy to determine: use the enthalpy of fusion (melting) and the specific heat capacity compared to your desired temperature drop. You can basically neglect all of the transfer resistances due to the tubing unless you're using plastic tubing, since they are orders of magnitude lower than your heat transfer rates in your cooling medium. Perhaps use a factor of 1.25-1.50 to correct for atmospheric loss, but its not substantial. You'll also want to maintain at least a 5C temperature difference between the medium and the target liquid in an effort to maintain a good driving force, perhaps 10C to overcompensate.

Water has an enthalpy of fusion of about 80C/g. Thus, 1 g of ice can cool 1 g of water by 80C. This neglects heat resistance, of course, but is a rough rule of thumb. To cool form 98 C to a target of something in the area of 25C, you'll end up needing about the same weight in ice of your wort. Addition of salt to the solution may reduce this slightly, making the liquid phase more stable at lower temperatures so a good rule of thumb is 1.5 the mass of your wort in ice with a good amount of salt (since it's not contacting wort, winter walkway salt is fine and cheap).

The result is something in the area of 50-60 lbs of ice to cool your wort sufficiently. The precise design of your apparatus is not very important as long as the cooling bath is well mixed. Additionally, you will always have a water film to overcome, so heat will have to be conducted through this region in the absence of convective force. With proper convective force (bulk flow), conduction plays a very diminished role, and may be neglected.

TLDR version: use 50-60 lbs ice per 5 gallons wort and stir it alot, the exact shape of your heat exchanger doesn't matter much if if you keep temperature uniform in a bulk ice bath. You may use salt to lower solution temperature and increase driving force.
 
i have stop using water to cool my beer for about 6 months. i am using a fluid called panatherm lr with glycol 50/50. I pump it out of my beer freezer into my counter flow at about 28 F. I also use the fluid to cool my fementing chambers. I agree i don't like to use water if i dont have to. :tank:
 
i have stop using water to cool my beer for about 6 months. i am using a fluid called panatherm lr with glycol 50/50. I pump it out of my beer freezer into my counter flow at about 28 F. I also use the fluid to cool my fementing chambers. I agree i don't like to use water if i dont have to. :tank:

Would you mind posting a pic or 2, I'm stepping up to a 30g system, and that sounds like what I'm planning on to doing with a therminator.
 
Well, seeing as though I have a closed wort cooling system that utilizes ice, I think I can say something.

#1. This will not be efficient at all. Why? You are melting the ice around the tubes, then that water just lies there, heating up... melting some ice, but there is VERY little surface area with the ice.

#2. You WANT the ice to melt quickly, why? When ice melts, that means that it is absorbing calories, when it melts slow, it means that it isnt cooling the wort (read not enough heat transfer)

#3. You need MAXIUMUM ice surface area, this is where you get MAXIMUM ice melt and therefore FASTER and more EFFICIENT cooling times.

I use 44# of ice, coupled with 3 gallons of water (to initially submerge my HERMS HEX coil where the wort travels) I use SMALL cubes to maximize surface area. I also have an agitator to keep the water/ice moving around the coil so that there are no "warm" spots near the coil.

If you are using a stationary coil in a SOLID block of ice, I dont see it going well. You are going to melt the ice right next to the coil, then that water surrounding the coiul will heat up and basically create an insualtor between the copper tube and the ice. This is not what you want, you want turbulence.

Just my $.02. My closed system works very well, we have a couple threads on the math that came before the build.

Just FYI, it takes me #44 of ice to cool 5 gallons of boiling wort to pitching temps in 20 minutes.

BrewBeastcooling.JPG
 
My cooling process results in 10 gallons of water at the end of the cooling cycle, this water is then used in my BK where it is heated and combined with cleaning agents for CIP cleaning of my HERMS system.
 
If you are worried about water use then go to a plate chiller and use chilled glycol and pointed out earlier.

Will the glycol be moving or just sitting in the chiller?

I probably spend 4x more time building stuff than brewing and applaud your approach!!-I tried freezing a coil in a bucket and then trickling wort thru it and it worked well but it will need some agitation to circulate the heat away from the tube and to maximize the effect from melting.It is easier for me to get water than huge amounts of ice so a combo worked best.I found putting the post chiller coil in a bath with water and ice and keeping the ice water melt in the bucket and adding a trickle on tap water from a garden hose with outlet in bottom of bucket (so warmest water on top will flow over top and out) to work VERY well and was simpler.."waterless" is not really what U have-it is reduced water

Water(less) was a sorry attempt at a play on words to say it uses "less" water.

Use a primary and secondary chiller. The primary could be a coil dropped into the wort which has another coil placed in a bucket of ice water. The down side is that you need a pump to transfer the fluid in the primary and you still need to keep the ice water agitated. But it would keep your water "waste" to a minimum and depending on your coils should drop the wort temp fairly quickly.

I'll be building this sometime in the near future, I'll let you know how it turns out.

Please post pics!

TLDR version: use 50-60 lbs ice per 5 gallons wort and stir it alot, the exact shape of your heat exchanger doesn't matter much if if you keep temperature uniform in a bulk ice bath. You may use salt to lower solution temperature and increase driving force.

Thanks this is a lot of great info!

i have stop using water to cool my beer for about 6 months. i am using a fluid called panatherm lr with glycol 50/50. I pump it out of my beer freezer into my counter flow at about 28 F. I also use the fluid to cool my fementing chambers. I agree i don't like to use water if i dont have to. :tank:

Yes I would love to see these pics too.

I use 44# of ice, coupled with 3 gallons of water (to initially submerge my HERMS HEX coil where the wort travels) I use SMALL cubes to maximize surface area.

If you are using a stationary coil in a SOLID block of ice, I dont see it going well. You are going to melt the ice right next to the coil, then that water surrounding the coiul will heat up and basically create an insualtor between the copper tube and the ice. This is not what you want, you want turbulence.

Just my $.02. My closed system works very well, we have a couple threads on the math that came before the build.

Just FYI, it takes me #44 of ice to cool 5 gallons of boiling wort to pitching temps in 20 minutes.

Can you link to these threads? Any pics?

EDIT: Nevermind you already did!


Thanks everyone I'm rethinking the design.
 
Here are some links:
https://www.homebrewtalk.com/f11/therminator-ice-water-whirlpool-question-140003/

https://www.homebrewtalk.com/f11/closed-system-wort-cooling-keggle-upgrade-pics-141707/

https://www.homebrewtalk.com/f11/closed-system-wort-cooling-works-140496/


It works well, but it benefits from turbulance in the cooling meduim so that there are no warm spots. You want the ice to melt FAST, as this is how you get those heat calories out of the wort. You also want to make sure you have enough ice to do the job, I dont see this being feasible at all on a 10+ gallon batch as you would then be looking at nearly 100 pounds of ice and 20 gallons of volume.
 
Just wondering, for you guys that live up north, can't you make your own chilling water? Isn't it cold enough up there to store a bunch of cold water in some kind of barrel or kid's pool and run this through your chiller?

I don't mind the cost of the ice (OK, that's a lie) as much as the inconvenience of having to buy it and store it somewhere for brewday.
 
Just wondering, for you guys that live up north, can't you make your own chilling water? Isn't it cold enough up there to store a bunch of cold water in some kind of barrel or kid's pool and run this through your chiller?

I don't mind the cost of the ice (OK, that's a lie) as much as the inconvenience of having to buy it and store it somewhere for brewday.

In the winter I use very little water to cool. but in the summer I use a lot.
 
The result is something in the area of 50-60 lbs of ice to cool your wort sufficiently. The precise design of your apparatus is not very important as long as the cooling bath is well mixed.

I see numbers thrown around like 40-60lbs of ice to bring down the wort. I have a very simple system with a bucket, a copper coil, a fountain pump, and 20lb of ice. You put the ice, pump, and some water in the bucket. The coil in the wort. circulate. I get from boiling down to pitching in maybe 10min. I then use the warm 4-5 gallons of cooling water in the laundry. environmental impact is low because the ice was produced at a nearby industrial ice plant. Im out $3 for ice.
 
The numbers being thrown around were derived from experiments in a closed system and it was 44lbs to reach lager temps. It would definitely take less ice to reach ale pitching temps AND the hot output water was not added back into the ice reservoir (which lines up with your findings). The OP is fleshing out ideas of a closed basin of ice as a heatsink which would act like the closed system (no method of removing the heat other than direct melting of ice). All in all, not a great idea.
 
ah, lager temps...I didnt think of that possibility...I only brew ales :D

the key to my systems quick cooling is that the return line to the bucket dump in the top, the pump is in the bottom. The circulation is pretty good. The pump is just a fountain pump from home depot that cost $30, it flows a rediculous amount of water. I actually have to choke the flow down so heat transfer in the coil is more efficient.
 
It takes me 20 mins to reach ale temps. with 44# of ice in a closed system. If I could melt the ice faster, I could decrease this time.

I have no idea how you can get 5 gallons to 70F in 10 minutes with ice water and a coil, that is amazing. I could never come close to that.

I can reach lager temps (57F) in 30 minutes.
 
Ill have to get some video next time I brew... I seriously use 20lb ice in about 1/2 gal water and some salt with a fountain pump and copper coil...are you doing more than 5 gal?
 
Ill have to get some video next time I brew... I seriously use 20lb ice in about 1/2 gal water and some salt with a fountain pump and copper coil...are you doing more than 5 gal?

Man if you say it works, I beleive you. I just know in my system that it never would. I couldnt halve my ice and cool it in even 20 minutes.

I am doing 5-6 gallons.
 
Man if you say it works, I beleive you. I just know in my system that it never would. I couldnt halve my ice and cool it in even 20 minutes.

I am doing 5-6 gallons.

Just chalk it up to different equipment and conditions I guess... I certainly dont want to argue about it... because I respect all the people on here who make their own and have their own experiences ;)
 
I dont respect anyone, or thier ideas, but I beleive you bro. :rockin:
 
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