How to cool the water from 48 deg. C to 16 deg. C?

[Jacek]

Hi,

Could someone tell me how I can cool the water from 48 deg. C to 16 deg. C?

I want to use a BAC cooling tower to cool the water from 48 deg. C to 27 deg. C (wet bulb 22 deg. C). Then I'd like to use York air-cooled chiller to cool the water from 27 deg. C to 16 deg. C... How can achieve such a big delta T? Mixing? Does the ***** chiller manage the water of 27 deg. C (or after mixing 27 deg. C)?

Many thanks in advance for your help.

Regards from Poland.

Jacek

[smpsmp45]

Is the water being recirculated? At what temp it is coming back? One important aspect is that since you are passing the water thru cooling tower, it can not be used in a chiller or for process due to contamiations etc.

In case the water is being recirculated, the aspects are different. If you can specify the flow rates & return temp I can suggest a system

[S.M.Gokhale]

Hi,
Regardless of your application, you can get such a high delta T in a Plate Heat Exchanger. The only other alternative - though not very practical - is to use a number of shell and tube heat exchangers in series.

[GXMPLX]

Yes you can use BPHE but large delta in the water side is not energy efficient.

I'd rather use two.

Yes you can use ***** but do not under size the first evap in order not to overload the compressor. Instead use a suction (crankcase) pressure regulator.

[paulh]

Jacek,
One problem with the York chiller is that the comp's are probably semi - hermetic. Normally the highest allowed leaving water temp is 10 deg. This is to ensure you get motor cooling. I have used them at 14 deg with problem but in a low ambient enviroment. To get from 27 - 16 deg hot and cold tank method the best. you a primary and secondary pump circuit.

[paulh]

Jacek, Ignore the first post had a keyboard problem.
One problem with the York chiller is that the comp's are probably semi - hermetic. Normally the highest allowed leaving water temp is 10 deg. This is to ensure you get motor cooling. I have used them at 14 deg with no problem but in a low ambient enviroment. To get from 27 - 16 deg the best method would be a hot and cold tank system with a primary and secondary pump circuit. Very popular on injection moulding and bottling plants using conventional chillers.

[JERRYCOOL]

If the water is circulated. Use BAC is good idea, the energy will be saved compared to using a chiller. I don't think it is a problem to cool the water from 27C to 16 C. It is only non standard evaporator.

[Don Davis]

You may also consider placing an air cooled heat exchanger ahead of the cooling tower to remove a substantial amount of the high quality heat. Tower would be smaller and evaporation losses less.

You should investigate putting the waste heat to good use elsewhere if possible.