Wort cooling with city water and cold water


 
Recently there are customers interested in cooling wort with double stage heat exchanger. And the cooling medium will be city water and cold water.
Let's do a simple calculation about it.
 
Usually the temperature of wort before cooling will be around 97°C.  And let's assume that city water temperature is 25°C, the cooled wort temperature is 10°C, cold water in the CLT is 5°C.
(The actual temperature of city water, cooled water and cold water will be a little different based on different situation. )
  
The two stages of temperature changing:
 
Stage 1: Wort from 97°C to 40°C, and city water from 25°C to 65°C.
Stage 2: Wort from 40°C to 10°C, and cold water from 5°C to 25°C.
 
Calculated based on our experience, 680L city water will be used in stage 1, and 600L cold water will be used in stage 2.
So in total, the warmed water temperature will be around 45°C, and the volume will be 1280L.
 
In next brewing, the whole water in the HLT need to be heated from 45°C to 78°C for sparging.
And the water needed for brewing is less than half of the warmed water produced.
 
In this case, two parts of energy will be wasted: one is the energy used for heating water from 45°C to 78°C, the other is the energy in the excess warmed water.
 
So in normally conditions, we suggest use a single stage heat exchanger with cold water as cooling medium, or double stage heat exchanger with city water and glycol water. 
 
Note: Each of the above temperatures and volumes are estimates.
 
Edit by Jane
E:[email protected]
 
Shandong Grain Machinery Co., Ltd.
Shandong Tiantai Beer Equipment Co., Ltd.