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EXERCISE VIII 

 COMPARATIVE EFFICIENCY OF ICE WATER AND BRINE AND ICE 



Use for this experiment a Tubular cooler. 



Heat two cans of milk to Q5F. The purpose of heating the milk 

 to this temperature is to have it nearly the same temperature as when 

 drawn from the cow. Weigh the amount of milk used. Weigh out 

 about 125 pounds of ice. Crush it and place it in the brine barrel. 

 Run in cold water until the barrel is about half full. Stir the mixture 

 of ice and water. Allow the pump to run for about two minutes or 

 until the temperature of the water in the barrel is 32 F. before run- 

 ning the milk over the cooler. Then run the milk over the cooler at 

 its full capacity. Record the length of time required to cool the milk 

 and take the temperature of the milk at the outlet faucet every three 

 minutes. Thoroughly stir the milk in the can and record the final 

 temperature. Record the temperature of the return water from the 

 cooler every three minutes. Weigh the amount of ice left. 



Repeat the experiment, heating the milk to 95 F. and using the 

 same amount of ice. The ice left from the previous experiment 

 may be used in this one. Add 40 pounds of salt to the mixture in this 

 barrel and thoroughly stir until the salt is dissolved. The amount 

 of salt required will depend somewhat on its quality. If it is insoluble, 

 more will be required. Have the temperature at 28 F. to 30 F. 

 Take temperature of the milk every three minutes, the temperature 

 of the return water every three minutes, and the final temperature of 

 the milk in the can. Weigh the amount of ice left. Draw diagram 

 of the cooler, and figure out its capacity per hour. Show in drawing 

 the relative position of the cooler, brine barrel, and pump. 



