Open System Chiller Operation

[Alex_Sor]

35 minutes ago, Hugote said:

Alex thank you so much for your response and for the explanation.

I should have studied more physics in school, you just made me a really happy man

I forgot to mention in my previous post a "little detail", I'll be distilling with a single pass through a 4 plates column, so once the water leaves the condenser will go to the dephlegmator and that will Increase for sure temperature, but according to you calculations even if the final temp of water was 70C after leave the dephlegmator 600 liters/water x hour will be still ok, right?

Hugo,

if you want a more accurate answer from me, then you need to provide me with more information.  

Thermal Engineering and Thermodynamics is a complex science with many non-linear relationships. You can't just take one thing and multiply it by two  

It doesn't matter how many plates you have in the column.

The important thing is that you have a dephlegmator. This means that you will have an adjustable reflux ratio in your moonshine still.

I do not know the area of the heat transfer surfaces in your dephlegmator and your condenser-cooler.

In my calculations, I have taken a reflux ratio of 1.8. If you have a different reflux ratio, the calculations will change.

So, for example, if the reflux ratio is = 1.1 this will give an alcohol release rate of 16.1 liters per hour. F, (square centimeters) = 1197.0 (increase).

With the same water flow rate (600 liters per hour from 20 degrees inlet), the condenser outlet temperature will be 47.9 degrees Celsius.

The dephlegmator will enter +47.9 degrees water, and it should not boil. Calculations (rough calculation) tell us that with reflux ratio = 1.8 and alcohol yield = 12.1 liters per hour, the surface area of the reflux condenser F, (square centimeters) should be = 1642.9.

This is more than the heat transfer area of the condenser.

In this case, at the exit from the reflux condenser, we get = 76.5 degrees Celsius. This is very hot water! And it will be 600 liters per hour!

I would recommend doing air cooling. For example, how people who have little money do it:

What is stand-alone cooling and how is it used? The autonomous cooling system works according to the following principle: water (that is, coolant) is pumped from the tank to the refrigerator (2) so that alcohol vapors condense. In this case, the liquid heats up and flows to the lower inlet of the radiator (3). The fan (3) and radiator from the car, cools the water to the ambient temperature. After that, the water returns through the upper pipe to the container (4). (5 = pump)

 

 

[Hugote]

Thank you so much Alex, you've been kind.

I got a lot of useful info, thanks.

Ps: congratulations on yesterday's victory, Ukraine played an incredible match

 

h

[Patio29Dadio]

Hugote - Sorry I missed your questions.  Alex_Sor has provided a ton of great information.

One thing for our system, it includes process controls to inject house water into the cooling loop when the tank level reaches a low point.   This is a bit sub-optimized for us as the chiller and heat exchange are designed to chill down our water overnight between processes... not have enough BTU power to chill the process water in use.  It is our 400G stripping runs that will overuse the 1600 gallons and require make-up water... thus potentially ending up with warmer condenser water toward the second half of the run.  However, with a Danfoss themo valve we can adjust the flow to the condenser to compensate.  We should have enough with our ~150G finishing still to cover a batch.  But again, we certainly cannot run out of process water, so the system will open up the house water valve as needed, and depending on the temperature of the city water, we will see the process water warm a bit.

In the future I will increase the size of my chiller and heat exchange.