Subtopic: Material and energy balances in food processing systems
Question Statement:
Milk enters a plate heat exchanger pasteurizer at $10.0^\circ\text{C}$ and is heated to $72.0^\circ\text{C}$. The pasteurized hot milk at $72.0^\circ\text{C}$ enters the regeneration section and preheats the incoming cold milk to $62.0^\circ\text{C}$. The percentage regeneration efficiency of the heat exchanger is ________ (round off to 1 decimal place).
Answer Key:
83.9
Step-by-Step Solution & Explanation
Regeneration efficiency is defined as:
$\%\text{ Regeneration} = \frac{\text{Temperature rise by regeneration}}{\text{Total temperature rise}} \times 100$
$\%\text{ Regeneration} = \frac{62.0 - 10.0}{72.0 - 10.0} \times 100 = \frac{52.0}{62.0} \times 100 \approx 83.87\% \approx 83.9\%$