Therminator, Ice Water, Whirlpool... question

[The Pol]

That seems logical, right?

 

[The Pol]

Probably don't need to say this but just in case...

Be sure to break up that block before you use it. Heat transfer is facilitated by surface area. A 5 pound block of ice doesn't cool nearly as well as 5 pounds of cubes.

It should cool just as well, but not as fast.

 

[The Pol]

Just picked up some overtime trip to ATL tomorrow, but I am all over this... I have to go to sleep. Thanks for the ideas, questions, equations etc... this doesnt seem impossible, it seems totally plausible to have a self contained 9 gallon cooling system on my brew stand.

I want to get this built and tested before my ext brew, so I need to get this all hashed out fast!

 

[arturo7]

Just a crazy thought...

Do you have a garage fridge? Put a reservoir in the freezer and tap a couple lines through the wall. Circulate a water/glycol mixture for your cooling.

I'm considering this to cool a conical for lagering. Not sure if it would have the BTU capacity for fast wort cooling.

 

[Donner]

I've read this thread and admit i don't remember half the math i learned that would help me understand this.

A few things i want to ask (so please excuse me if they are dumb questions/points).

How much of the water will be in the system at any one time? If you are running five gallons (initially) through the system, how much water is left in the mlt when the hot water returns? If the system holds even three gallons at any one time then the water left in the MLT wont be able to equalize fast enough to stay at a cool enough temp. Bobby_M point this out in an earlier post, i think. The ice will absorb some of the heat, but wont cool fast enough to cool the water back down before it returns to the system. Cubed ice would help as it would have an increased surface area to help the transfer.

Again, i could, and probably am wrong, but it seems like you have to account for how much water is in the system vs in the MLT to absorb the heat.

 

[The Pol]

I've read this thread and admit i don't remember half the math i learned that would help me understand this.

A few things i want to ask (so please excuse me if they are dumb questions/points).

How much of the water will be in the system at any one time? If you are running five gallons (initially) through the system, how much water is left in the mlt when the hot water returns? If the system holds even three gallons at any one time then the water left in the MLT wont be able to equalize fast enough to stay at a cool enough temp. Bobby_M point this out in an earlier post, i think. The ice will absorb some of the heat, but wont cool fast enough to cool the water back down before it returns to the system. Cubed ice would help as it would have an increased surface area to help the transfer.

Again, i could, and probably am wrong, but it seems like you have to account for how much water is in the system vs in the MLT to absorb the heat.

The planned mixture is 40lbs ice and 4 gallons of water (about 50/50). The ratio of water to ice will increase fairly quickly once the initial recirc starts.

The ICE pump will be flowing at about 2 gallons/minute, so the initial volume of water will turn over once every two minutes.

The ice WILL BE CUBES... a good point was made earlier about this fact. I need to maximize surface area so that I can melt the ice as fast as possible. The faster it melts, the better the cooling (read more calories being consumed in less time).

The hot return water will be delivered to the TOP of the MLT, the pump will be pumping out the bottom. It will take, theoretically, at a rate of 2 gal/min, 2 minutes for the HOT return water to reach the outlet of the MLT and go back to the chiller.

 

[The Pol]

Here are some initial #s from the plate chiller mfg.

Cooling water temp. 32F (ice water)
Cooling water flow 2gal/min
Cooling water exhaust temp: 155F

HOT fluid temp: 208F
HOT fluid flow 2gal/min
HOT fluid exhaust temp: 85F

Of course, as the 155F exhaust enters the MLT, that water will not be at 32F. Though for the first two minutes it should be close as I cycle through the water (4 gal) in the MLT and the ice begins to melt.

Assuming I can melt ALL of the ice, the cooling water will still only equalize at 58F according to the math.

The first 4 gallons of wort should come close to 85F on the chiller output. If I average the 4 gallons at 85F with the remaining 1.5 gallons at 208, the kettle should equalize at 119F. This is in two minutes.

The next two minutes will take assumptions. IF the cooling water enters the chiller at 50F, at the same flow rates. The next 4 gallons will exit at 68F, the cooling water will exit at 91F.

The kettle then would be equalized at 82F, this is after 4 minutes.

The next 2 minutes, if I assume the cooling water temp is at 60F (above where it should settle with ALL ice melted)... then the wort exiting the chiller will be 66F. The cooling water exit temp will be 75F...

The kettle would then equalize at 70F. This is after 6 minutes.

From here on out, I dunno... I need to run a test and stop the conjecture. When I get this up and running I will take temps at 2 minute intervals in the kettle and in the MLT

 

[Boerderij_Kabouter]

For the ice, just use your ice maker and collect the cubes in your 5 gallon bucket until you have 40#.

I think this is a really cool idea. Way to go Pol!

 

[The Pol]

The chiller calculators on Duda are awesome, they help in making calculations that I could not make otherwise. I am not settled on a chiller yet, but I will be soon.

 

[Dog House Brew]

Let us know the one you choose

 

[The Pol]

Let us know the one you choose

It will be from Duda... I am not sure on the model. Thier $110 model has about 1' more surface area than the Therminator, I may go one model larger.

 

[Bobby_M]

Here are some initial #s from the plate chiller mfg.

Cooling water temp. 32F (ice water)
Cooling water flow 2gal/min
Cooling water exhaust temp: 155F

HOT fluid temp: 208F
HOT fluid flow 2gal/min
HOT fluid exhaust temp: 85F

Of course, as the 155F exhaust enters the MLT, that water will not be at 32F. Though for the first two minutes it should be close as I cycle through the water (4 gal) in the MLT and the ice begins to melt.

That's why I'd recommend catching the first 3-4 gallons of output in a bucket. OK, it's not a completely closed system anymore but everyone's got a few buckets sitting around. Start with two buckets, one empty and one filled with 4 gallons of room temp tap water. When you start chilling collect 4 gallons of the initial exhaust. Dump the room temp water into your reservoir. That would probably reduce the amount of ice needed by like 10 pounds. Pure speculation. Then again, everyone can use a little hot water for cleanup. Two birds.

Also, if you ran the coolant flow really slow for a minute, it would come out even hotter so you'd collect less.

One other note... you don't seem too concerned with absolute speed of chilling. In that regard, bigger and more plates isn't better. It will just hold more wort.

 

[The Pol]

I am not concerned about absolute speed, as I think it will beat an IC any day. (I may eat my words later)

Good point Bobby on the initial outflow, I will have to run a test doing both to see what the difference is in cooling time.

I DO plan to use ALL of this cooling water to clean with. After cooling, it will be transferred to my rinsed kettle, combined with Oxi and used to clean the kettle, chiller and pump...

I plan to test this as thoroughly as possible to get good data to put up here. If a closed system works, someone may be interested in it later.

 

[arturo7]

Start with two buckets, one empty and one filled with 4 gallons of room temp tap water.

Might as well make it a bucket full of ice water while you're at it.

 

[Bobby_M]

All the better to save a bit of the hottest water then too. It cleans up better than luke warm water.

 

[The Pol]

All the better to save a bit of the hottest water then too. It cleans up better than luke warm water.

True, but I always end up using the kettle to heat the cleaning solution anyway that I use in my system... Catching a few gallons of 155F water 30-60 minutes before I clean, may not "add" alot.

I love the recommendations, so keep them coming... I am by no means an expert on closed system chilling at this point. I am living in theory only. I may not implement all suggestions since I have a specific goal in mind, but please keep brain storming, it is helping me greatly.

THANKS BOBBY for your post yesterday that allowed me to use math to prove that this is def. worth trying.

 

[jppostKW]

An idea on the whole cube vs . Block problem when you make the bucket block place a few copper pipes in it that are closed at atleast one end to provide passages for the water to flow. The surface area of ice to water would actually increase as the block melted. And removal of the tubes would be easy after filling the coolant holding tank with tap water.

 

[The Pol]

An idea on the whole cube vs . Block problem when you make the bucket block place a few copper pipes in it that are closed at atleast one end to provide passages for the water to flow. The surface area of ice to water would actually increase as the block melted. And removal of the tubes would be easy after filling the coolant holding tank with tap water.

This IS true, however I think the TOTAL surface area of the cubes will far outweigh the surface area I could create with a large block. Also, key to this process is getting the ice to melt FAST (6-10 miuntes)... I think a block, in any form, will melt much too slowly.

 

[jppostKW]

I must have missed the plan to go to cubes I have been following this thread and am thinking of doing the same thing ish. I am liking the block with holes because I have no acess to large amounts of cubes where as I can make a block in the freezer. When this gets up and running I think the hbt community will have many variations and we can all compare notes.
Good luck
Paul

 

[The Pol]

I must have missed the plan to go to cubes I have been following this thread and am thinking of doing the same thing ish. I am liking the block with holes because I have no acess to large amounts of cubes where as I can make a block in the freezer. When this gets up and running I think the hbt community will have many variations and we can all compare notes.
Good luck
Paul

Yeah, this will be cool to get up and running...

I hope to make this successful!

The ice should definately have the cooling power to do this, BUT the ice MUST melt fast. If it doesnt, then that means that it is eating up the calories, or BTUs, too slowly.

 

[Lil' Sparky]

So are you just making and storing up a bunch of cubes from your ice maker, or are you going to freeze a block and then break it up somehow?

 

[The Pol]

So are you just making and storing up a bunch of cubes from your ice maker, or are you going to freeze a block and then break it up somehow?

Cubes, in order to provide uniformity in the entire process, I think this is best. I have an ice machine that will produce plenty of ice for this process.

 

[The Pol]

Closed sytem cooling works, here are the ACTUAL numbers. As the math predicted... the cooling water settled at 48F after ALL of the ice melted. Damn!

Closed system cooling WORKS, here are some numbers:

5.5 gallons BOILING
4.0 gallons 65F water and 44 pounds of ICE

5 minutes in:
COOLING WATER TEMP 50F
KETTLE TEMP 148F

10 minutes in:
COOLING WATER TEMP 54F
KETTLE TEMP 99F

15 minutes in:
COOLING WATER TEMP 52F
KETTLE TEMP 81F

20 minutes in:
COOLING WATER TEMP 50F
KETTLE TEMP 66F

25 minutes in:
COOLING WATER TEMP 48F
KETTLE TEMP 57F

30 minutes in:
COOLING WATER TEMP 48F
KETTLE TEMP 57F

 

[beretta]

Awesome read... thanks for the "hard" numbers Pol. I separately verified the "closed" system ice system, and by my calculations it takes 34 lbs of ice to cool 5.5 gals of wort to 68*F. In fact, I use an "open" cooling system, until I hit 100*F. Then I switch to a closed ice water system, using roughly 4 gals of water and 7 lbs of ice at 5*F. This is premised off the exact same math. In fact, I just let the system run while I clean up the brewery, sanitize things, clean, etc.... once I see that all the ice has melted, I empty the kettle into the fermenter. My cooled wort is always 67-69*F. I don't even bother using a themometer anymore... the physics of the closed system is VERY perdictable.

Also: If your water in our MLT starts at nearly your pitching temp (65-70*F) It has VERY LITTLE effect to the cooling of the system... the ICE does all the work, and the water is simply just a transfer medium, and even at 4 gals worth, doesn't affect the math much at all....

BTW: I used to use 20 once blocks of ice, rather that standard ice cubes.... it takes 10 minutes longer to melt the same amount of ice. Now I use regular ice cubes and my cooling is much shorter....

Also: It takes about 6985 KJ of enery to get wort from 212*F to 68*F... that's roughly 2 KWH. IF your electric company charges you $0.10/ KWH, and your freezer uses 5X the power to make the ice (that's 20% Efficiency)... it'll cost you a whopping $1.00 too cool your wort. (This is shakey: there's a lot of variables concerned) Is that cheaper that an open system that sucks a lot of city water? Food for thought....

I love this site...

 

[The Pol]

Very sweet.

Yes it worked, and the 44 pounds of ice ended up with PLENTY of cooling power. The fact that the ice melted in 20 minutes was excellent as well, as this means that the heat transfer to the ice was quite efficient. Cooling power means little if it takes forever to transfer the heat to the cooling medium.

My HERMS coil is a 1/2" x 25' coil, it has 7.3' of surface are, about a foot more than the Therminator. About 4x as much as the Chillus Convolutus.

I recirculated the wort as fast as the pump would go, at about the 10 minute mark, the wort was cool to the touch as the HLT cooling water was gaining on the rest of the system. The cooling water was actually getting COLDER during the process.

You are also right, in a closed cooling system it will be very predictable, as there is no variation in the cooling meduim temp. I presume that I can sanitize everything by circulating wort through the pump and coil during the last 10 minutes of the boil. Then, drop it in the cooling medium and go.

 

[Dog House Brew]

So when you recirced this how did you/or will you handle the cold break with the hop trub?

 

[The Pol]

So when you recirced this how did you/or will you handle the cold break with the hop trub?

I have a SS scrubby filter on my dip tube end, some stuff will get through, but this is no biggie. All of this will remain in the kettle, hopefully the whirlpooling will build a nice cone.

 

[Dog House Brew]

Does the scrubby do a nice job once it cools? You may have me on this. I would love to leave the break in the kettle, but also want it to drain. I'm not into dropping cash if I can make something work. I don't have a herms, but the principle works none the same. I hate the thought of a plate and hate the thought of a convolutous. Love it when a plan comes together. Now that $400 starts a new DIY conical thread.

 

[The Pol]

I have used the scrubby a long while, that combined with setting the dip tube off the bottom works reall well for me. I am interested to see what the whirlpooling does in the kettle with hops and break.

 

[Boerderij_Kabouter]

The whirlpooling like this works very well once you get it tuned. I circulate for my cooling, then allow the system to rest for 20 minutes while I clean up. When I come back, most of the break is in the center of the kettle and not in my fermenter. I am thinking of adding a filter bag from Duda to my setup to get that last bit of break and trub.