Closed wort chiller system

Hey guys I had an idea for cooling wort and saving water, I wanted to see what you guys thought.

So it is pretty basic, a closed system using a radiator with an electric fan for cooling, and a counter flow for the wort, powered by a 1hp cast iron pump.

So basically it would look like this:

|-----<------Counter flow-----------|
| -- Reservoir--pump--radiator---->--|

Thoughts?

Your going to need a mighty big fan to push air over the radiator to cool the water loop. Keep us posted.

There isn't anything simple about this idea.

A fan wouldn't really cool the water from whatever brief exposure it has, it would just cause some surface evaporation.

Without much cooling of your reservoir the hot outflow will warm the water going in, so the temperature will equalize in the middle between boiling (the wort's initial temp) and the initial temperature of the reservoir water. If the reservoir's initial temperature, I'd guess the wort and water temperature would equalize somewhere around 120 degrees.

So you would either need a huge reservoir (and some way to cool it to near-freezing) or you would need a smaller amount of something like antifreeze that has been cooled to near zero, which would certainly be way too dangerous to even consider using.

Yeah i was honestly thinking taking an automotive radiator and e-fan assembly, just hard wiring it.

@Mojo_wire
That is kind of what i was thinking i would run into that with this project. That is why i wanted to see what you guys thought. Other than the counter flow that i have now, what kinds of cooling methods would you recommend that can be be as efficient?

Air is just horrible at taking heat away but it MIGHT work OK if the radiator was outside in 10F air. It would still take a long time. The most efficient way to go is use tap water until you get the wort to 100F, then pump icewater for the rest of the way. My version of "efficient" is striking a balance between using the least amount of energy/money to cool to pitching temp and how long it takes. Certainly cost and time are generally on opposite ends of the spectrum.

That is an excellent point, maybe I can just save the run off water for cleaning my equipment at the end haha.

heat transfer is pretty simple. if you have 5 gallons of 200* wort and a 5 gallon resevoir of 0* cooling water (for the sake of keeping numbers easy), when you pump them both thru a heat exhanger (without any radiator to remove heat) you will end up with all 10 gallons at 100 degrees.

if you had 5 gallons of 200* wort and a 20 gallon resevoir of 0*water, the temperature that they would equalize to would be 40 degrees. how do you get that you ask?

the total volume (or thermal mass; 5g + 20g) is 25 gallons.
5 of those gallons (20% of the total volume) are at 200*.
20 of those gallons (80%) are at 0*. so
25 gallons is going to be [cold temp] + 20% of [temp delta] = [final temp]
[0*] + [20% of (200*-0*= 200)] = [40*]

Now- when you add a radiator it gets a little more complicated, but still doable. you can use the above calculation and combine it with the heat radiation capacity of your radiator (determined by the airflow over it, and the liquid flow thru it, mainly), and work out how much heat you are able to chill the wort by in a given amount of time.

tl&dr:
|-----<------Counter flow-----------|
| -- Reservoir--pump--radiator---->--|

yes you can do that.

the more steps you add though, the slower the results will be. for example, if you ran the wort directly thru the radiator, it would be more efficient than running the worth thru a counterflow chiller, and then pumping the water from the other side of the counter flow thru a radiator. but the end result is the same.

@audger and everyone else thanks for the info it was really helpful!

Charlie