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cooling water after process

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yamooo65

Mechanical
Oct 24, 2012
2
Hello, im looking for diffrent ideas to cool water. Basically i have city water at 65f that runs thru copper and runs out of drilled holes over a hot drum which heats it up to about 102f and then runs into a drain...big waste, not to mention big water bill. So we would like to re-use this water by re-useing it and bringing the temperature back down to 65F. in basically an endless cycle. We are in the north east so winter weather is a factor and 65f is the optimal temp of the water we need at the start. Thanks for any ideas
 
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A lot depends on how much space you have and how much money you want to spend. You can probably reuse the water if you have place to store it and a place for a heat exchanger and a source of water cooler than 65°F. If you don't have a source of water cooler than 65°F, and that really is your optimal process temperature something is going to have to give.
 
Thanks for your input, space is no problem, we are considering some sort of water cooler thats why im trying to get diffrent ideas as to how to do this we are in the process of costing so the more ideas the better and long term operating cost also has to be considered..we were thinking cooling tower but im unsure how well that would work in the winter with 30 mph winds at 20 degrees..a condensor style would plug the coil too quick so we have ruled that out
 
Cooling towers are used in lot colder climates like that and you can get small packaged units. However, getting your cooled water back to 65F would be a challenge in summer I'm thinking unless you have low summer air temperatures and air humidity.

If you have lots of available real estate you can spray the water into open ponds. You'll get some cooling from the spray stage and the rest by exchanging heat with the air but this is going to give you warmed water than a cooling tower.

A lot is going to be driven by your water costs. What sort of payback would be needed? That and your current water cost would give you an idea of how much the system could cost and some phone calls to vendors would let you know if it was even feasible to pursue.
 
It's obviously not going to be a free ride. Your "optimum" statement implies that water that's too cold is also a problem, so you need to have cooling, followed by possibly heating, or temperature control the cooling tower to get the desired water temperature for the return. Lots of pumping, lots of valving, and lots of infrastructure. You don't say what the duty cycle or use case looks like; that'll have a big impact on what you need to do.


TTFN
faq731-376
7ofakss
 
The alternative could be a refrigeration cycle.
How much is the water flowrate?
 
I would go for a cooling tower too. 65 F (18 C) is a bit low for summer conditions. But maybe an evaporating type (or a relaxation on the low temperature and an increase in flow rate)?
 
If you have enough real estate, a ground loop may work. I would guess that's what keeps the domestic water at 65 F to begin with, so it could be used for cooling or heating.
 
What sort of GPM are you dealing with?

The optimal solution will depend on the economics of the problem, including capital equipment costs, the cost of power and water in your area.

A friend of mine had a photo lab (back in the old days of film) that required a few GPM of cool water to control process temperatures. The original installation just took city water, ran it through the heat exchanger and dumped it into the drain. After the city started hitting him up with big water bills, he acquired a drinking fountain chiller and pump. Plumbed the thing into a loop to recycle the water and (by his estimation) saved quite a bit of money (Seattle WA power rates were low back then).

[fish]
 
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