Advantages of Bare Tube Low Pressure Boiler Economizer

Advantages of Bare Tube Low Pressure Boiler Economizer

Heat Transfer Performance

Moderate Efficiency: Bare tubes have lower heat transfer coefficients (typically 30–60 W/(m²·K) for flue gas-side) compared to finned tubes (80–150 W/(m²·K)), but this is acceptable in low-temperature, low-heat-flux zones (e.g., flue gas temperatures 150–300°C).

Dependence on Turbulence: Heat transfer is enhanced by flue gas velocity (optimized at 8–12 m/s); staggered arrangements or increased gas velocity compensate for the lack of fins.

Operational Advantages

Resistance to Fouling and Erosion:

Bare tubes are less prone to ash deposition or clogging, making them ideal for flue gases with high ash content (e.g., coal-fired boilers) or sticky particulates (e.g., biomass fuels). Fins, by contrast, trap debris and require frequent cleaning.

Smooth surfaces reduce erosion from abrasive particles (e.g., fly ash), extending tube lifespan in high-velocity flue gas streams.

Simplified Maintenance:

Easy to clean via high-pressure water washing, mechanical brushing, or sootblowers (steam/air). No risk of fin damage during cleaning, unlike finned tubes.

Lower risk of corrosion under deposits (CUD) since ash buildup is minimal, reducing maintenance costs.