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oroco
12-07-2010, 05:59 AM
Can you please help me calculate refrigeration load for 200,000 litres per day milk plant? Kindly give me a step by step calculation.

lana
12-07-2010, 06:35 AM
Hi there,

You did not mention the time requirement. Usually dairy companies receive a huge amount of milk everyday and it must be cooled very quickly say 1 hour. For this reason every company has an ice storage system. This means a relatively small refrigeration system works for 24 hours and produces ice around evaporator tubes. Then the latent heat of ice is used to cool the milk in a short time. This is called ICE BANK.

About the load : m x Cp X DT = Q
where :
m is the mass flow rate of the fluid to be cooled in kg/s
Cp is the specific heat of the fluid in kJ/kg°K
DT is the temperature difference in °C

Q = (200000/24*60*60)*3.7*(30-2) =2.31*3.7*28 = 239 kW
(assuming that milk density is 1000kg/m³ like water. Means 1 liter of milk equals one kg.)

Cheers

Sandro Baptista
12-07-2010, 03:52 PM
just a correction, despite the final result is correct:
» (200000/(24*60*60))*3.7*(30-2)

time in seconds for cooling (S.I. units) » 24hours*60min*60seconds