Question:
The part of HTST pasteurizer that limits its application with respect to temperature is
The part of HTST pasteurizer that limits its application with respect to temperature is
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Plate Heat Exchanger Limitations: GASKETS (Elastomers like NBR/EPDM) limit the maximum temperature in plate pasteurizers ($T_{\max} \approx 140^\circ\text{C}$) due to thermal hardening.
Updated On: Sep 15, 2026
- Heat transfer plate
- Gaskets
- Connecting plates
- Pressure plates
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Verified By Collegedunia
The Correct Option is B
Solution and Explanation
Step 1: Understanding the Concept:
Plate heat exchanger (PHE) thermal elastomer limitations: corrugated stainless steel plates withstand $> 200^\circ ext{C}$, but elastomeric polymer sealing gaskets (NBR, EPDM, Silicone) undergo thermal degradation, hardening, and compression set above $135-145^\circ ext{C}$, limiting PHE pasteurizer operating temperatures.
Key Formula or Approach:
\[ \text{Operating Limits: Stainless Steel Plates (} T > 300^\circ\text{C)} \quad \longleftrightarrow \quad \mathbf{Elastomer \text{ } Gaskets (NBR: } T_{\max} \le 110^\circ\text{C}, \; \mathbf{EPDM: } T_{\max} \le 140^\circ\text{C)} \]
Step 2: Detailed Explanation:
In dairy processing plant engineering and Plate Heat Exchanger (PHE) design:
- A continuous HTST plate pasteurizer comprises stainless steel heat transfer plates clamped together and sealed along channels with elastomeric gaskets:
1. Heat Transfer Plates (AISI 304/316) (A): High-grade stainless steel easily withstands temperatures exceeding $300^\circ ext{C}$ and pressures up to $25\text{ bar}$.
2. Gaskets (B): Molded from synthetic elastomers (Nitrile Butadiene Rubber [NBR], Ethylene Propylene Diene Monomer [EPDM], Fluoroelastomers [Viton]):
- Under continuous exposure to high steam/hot water temperatures ($> 135^\circ - 140^\circ ext{C}$), elastomer chains cross-link, lose elasticity, harden, and experience compression set failure, causing fatal product cross-contamination and liquid leaks.
- Therefore, the Gaskets represent the critical weak link that strictly limits the maximum operating temperature and steam application of HTST plate pasteurizers.
Step 3: Final Answer:
Therefore, the part that limits application with respect to temperature is Gaskets, corresponding to option (B).
Plate heat exchanger (PHE) thermal elastomer limitations: corrugated stainless steel plates withstand $> 200^\circ ext{C}$, but elastomeric polymer sealing gaskets (NBR, EPDM, Silicone) undergo thermal degradation, hardening, and compression set above $135-145^\circ ext{C}$, limiting PHE pasteurizer operating temperatures.
Key Formula or Approach:
\[ \text{Operating Limits: Stainless Steel Plates (} T > 300^\circ\text{C)} \quad \longleftrightarrow \quad \mathbf{Elastomer \text{ } Gaskets (NBR: } T_{\max} \le 110^\circ\text{C}, \; \mathbf{EPDM: } T_{\max} \le 140^\circ\text{C)} \]
Step 2: Detailed Explanation:
In dairy processing plant engineering and Plate Heat Exchanger (PHE) design:
- A continuous HTST plate pasteurizer comprises stainless steel heat transfer plates clamped together and sealed along channels with elastomeric gaskets:
1. Heat Transfer Plates (AISI 304/316) (A): High-grade stainless steel easily withstands temperatures exceeding $300^\circ ext{C}$ and pressures up to $25\text{ bar}$.
2. Gaskets (B): Molded from synthetic elastomers (Nitrile Butadiene Rubber [NBR], Ethylene Propylene Diene Monomer [EPDM], Fluoroelastomers [Viton]):
- Under continuous exposure to high steam/hot water temperatures ($> 135^\circ - 140^\circ ext{C}$), elastomer chains cross-link, lose elasticity, harden, and experience compression set failure, causing fatal product cross-contamination and liquid leaks.
- Therefore, the Gaskets represent the critical weak link that strictly limits the maximum operating temperature and steam application of HTST plate pasteurizers.
Step 3: Final Answer:
Therefore, the part that limits application with respect to temperature is Gaskets, corresponding to option (B).
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