Views: 0 Author: Site Editor Publish Time: 2025-09-02 Origin: Site
Finned Tube Heat Exchanger for Flue Gas Heat Recovery
The heat recovery process relies on the enhanced heat transfer capability of finned tubes, which address the low heat transfer coefficient of flue gas (a gas with poor thermal conductivity). Here’s how it works:
Heat Source Side: High-temperature flue gas (typically 150–1000°C, depending on the industry) flows through the shell side or tube side of the exchanger, transferring heat to the outer surface of the finned tubes.
Heat Sink Side: A low-temperature medium (e.g., boiler feedwater, combustion air, or process fluid) flows inside the tubes, absorbing heat from the tube walls.
Fins’ Role: Fins attached to the outer tube surface significantly expand the heat transfer area (2–10x larger than bare tubes). This compensates for the low heat transfer coefficient of flue gas, dramatically improving overall heat exchange efficiency.
Finned tube heat exchangers for Flue Gas Heat Recovery are widely used across sectors to recover waste heat for different purposes:
| Industry | Flue Gas Source | Heat Recovery Purpose | Example Outcome |
|---|---|---|---|
| Power Generation | Coal-fired/gas-fired boilers | Preheat boiler feedwater or combustion air | Reduces boiler fuel consumption by 5–10%; lowers flue gas discharge temp to 80–120°C. |
| Steel Industry | Blast furnace, rolling mills | Preheat air for combustion or heat thermal oil for processes | Cuts energy costs by 15–20%; reduces CO₂ emissions by 10–15%. |
| Chemical/Petrochemical | Reformer furnaces, incinerators | Preheat process fluids or generate low-pressure steam | Improves process energy efficiency; replaces fossil fuel for low-grade heat needs. |
| Waste-to-Energy Plants | Incineration flue gas | Heat feedwater for steam turbines or district heating | Enhances energy recovery rate from waste; reduces reliance on grid electricity. |
