Question

The major advantage of regeneration section is:

• A. reduced thermal conductivity
• B. reduced energy consumption
• C. reduced specific heat
• D. reduced flow velocity

Hint:

Regeneration is a highly effective energy recovery technique that pre-heats cold incoming milk using hot outgoing pasteurized milk, saving up to 95% of heating and cooling energy.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Regenerative heat exchange is an energy recovery process used in pasteurization plants.
It transfers thermal energy between two streams of the same fluid: one cold stream that needs to be heated, and one hot stream that needs to be cooled.

Step 2: Detailed Explanation:
In an HTST pasteurizer, cold raw milk entering the system at approximately 4$^\circ$C is passed through the regeneration section.
On the opposite side of the heat exchanger plates, hot pasteurized milk at approximately 72$^\circ$C flows in counter-current fashion.
The hot milk transfers its heat to the cold raw milk, preheating it to about 60$^\circ$C to 65$^\circ$C before it reaches the final heating section.
Simultaneously, the hot pasteurized milk is pre-cooled to about 15$^\circ$C to 20$^\circ$C before it reaches the cooling section.
This mutual heat exchange significantly reduces the external thermal energy required for final heating (steam or hot water) and final cooling (chilled water).
This process can recover up to 90% to 95% of the heat, leading directly to a dramatic reduction in the utility and energy consumption of the dairy plant.
Regeneration does not alter physical properties like thermal conductivity or specific heat, nor is it designed to modify flow velocity.

Step 3: Final Answer
The correct option is (B).