Water / pond cooling loop for 25T chiller.
Water / pond cooling loop for 25T chiller.
(OP)
Good day all,
I am currently installing a 25 ton chiller in a cogen facility, and am planning on placing the cooling loop in a large settling pond we have on the front of the property. I am having a hard time sizing the cooling coils, as I find little information on what length per ton of cooling loop I need. I have found a bit for direct burial, on the order of 600' to 800' cooling coil length per ton, but little on submersed cooling.
Does anyone out there have any ideas, or tips?
Thanks in advamce.
I am currently installing a 25 ton chiller in a cogen facility, and am planning on placing the cooling loop in a large settling pond we have on the front of the property. I am having a hard time sizing the cooling coils, as I find little information on what length per ton of cooling loop I need. I have found a bit for direct burial, on the order of 600' to 800' cooling coil length per ton, but little on submersed cooling.
Does anyone out there have any ideas, or tips?
Thanks in advamce.





RE: Water / pond cooling loop for 25T chiller.
You are designing your own heat exhanger and it is numerically complicated, but a Heat Transfer textbook will get you there.
Or you can call a heat exchanger manufacturer and see if he can model it. Check his answer carefully.
RE: Water / pond cooling loop for 25T chiller.
Just wondering...
RE: Water / pond cooling loop for 25T chiller.
RE: Water / pond cooling loop for 25T chiller.
I believe what MintJulep is pointing out is that you are suggesting what is considered an un-steady state heat transfer that is limited to the static heat sink that the pond of water represents. You can't continue to use the pond as a heat sink indefinitely since you're not making up the heat pickup with cooling through vaporization of the water - so the cooling effect will only last to the extent of the pond's size. Hopefully it's more like a Lake, instead of like a pond.
For a submerged pipe with refrigerant inside the pipe, use a "U" of approximately 75 Btu/ft^2-hr-oF for design purposes. I can assure you that this value will work. But with the water temperature increasing, I don't know for how long.
I wouldn't do it this way.
RE: Water / pond cooling loop for 25T chiller.
I had my doubts about this approach, and after consulting a geothermal designer, I was presented with the facts on the performance of this. There is insufficient water quantity for the load I have. My first choice was a simple dedicated cooling tower, but the owner here prefers to experiment, not always considering factual data. I will present the facts at the next facility meeting, and hopefully win over hearts and minds.
Thanks again.
RE: Water / pond cooling loop for 25T chiller.