Industrial Single Inlet CFB Boiler Blower Fan 2900r/min Anticorrosion

This article's table of contents introduction:

1. Key Technical Specifications (Typical)
2. The "Anticorrosion" Aspect (Critical for CFB)
3. Typical Construction (Materials & Features)
4. Application in CFB Boiler
5. Advantages of a Single Inlet Design for CFB
6. Potential Challenges & Solutions
7. Common Models / Standards
8. Example Specification for a Procurement Inquiry
9. Recommendations for Purchase

Based on the keywords you provided, here is a detailed breakdown of the specifications, common features, and considerations for an Industrial Single Inlet Centrifugal (CFB Boiler) Blower Fan operating at 2900 r/min with Anticorrosion properties.

This type of fan is a critical component in a Circulating Fluidized Bed (CFB) Boiler system, typically serving as the Primary Air (PA) Fan or Secondary Air (SA) Fan.

Key Technical Specifications (Typical)

• Type: Single Inlet, Centrifugal (Forward Curved or Backward Inclined/Curved).
  • Backward Curved (e.g., 9-19, 9-26 series): More common for high-pressure CFB applications. More efficient, non-overloading power curve.
  • Forward Curved: Used for lower pressure, higher volume applications (e.g., draft fans).
• Speed: 2900 r/min (Standard 2-pole motor speed at 50Hz).
• Flow Rate: Varies widely (e.g., 10,000 – 200,000 m³/h).
• Pressure: High static pressure (e.g., 6000 – 15,000 Pa) to overcome the deep bed resistance in a CFB boiler.
• Impeller: Single inlet, often with wear-resistant lining or hard-faced blades (due to fly ash erosion) in addition to anticorrosion coating.

The "Anticorrosion" Aspect (Critical for CFB)

The environment inside a CFB boiler flue gas path is highly corrosive due to:

• SOx, NOx, HCl gases.
• Acidic condensation when the fan is operating at lower temperatures (e.g., during startup or after wet flue gas desulfurization - WFGD).
• High humidity (especially if used as an Induced Draft - ID - fan downstream of scrubbers).

Typical Anticorrosion Solutions:

• Material Selection:
  • Impeller: Stainless Steel (e.g., 304, 316L, or Duplex 2205) or Corten Steel with epoxy/polymer coating.
  • Housing: Lined with FRP (Fiber Reinforced Plastic), Rubber, or Stainless Steel cladding.
• Coatings:
  • Heavy-duty Epoxy (e.g., based on Novolac epoxy) – High chemical resistance, good for dry to mildly wet acids.
  • Vinyl Ester – Superior resistance to both acidic and alkaline environments.
  • PTFE (Teflon) lining – For extreme chemical resistance (more expensive).
• Design Modifications:
  • Drain holes in the scroll casing to prevent acid accumulation.
  • Shaft sealing with purge air to prevent corrosive gases from reaching bearings.
  • Stainless steel hardware (bolts, nuts).

Typical Construction (Materials & Features)

Application in CFB Boiler

This specific fan is most likely used as:

• Primary Air Fan (PA Fan): Supplies the air to fluidize the bed material (sand/ash). Needs high pressure (to lift the bed) and anticorrosion (to handle preheated air or flue gas recirculation).
• Secondary Air Fan (SA Fan): Provides over-fire air to complete combustion. Lower pressure, higher volume.
• Induced Draft Fan (ID Fan): Draws flue gas out of the boiler. Highly susceptible to corrosion (acid dew point). Often requires the most aggressive anticorrosion lining.

Alternative: Fluidizing Air Fan (for limestone or coal feeding systems): Needs anticorrosion if handling damp fuel.

Advantages of a Single Inlet Design for CFB

• Compactness: Smaller footprint than double inlet (since CFB boiler houses have limited space).
• Efficiency: Higher static pressure efficiency (up to 85%) compared to double inlet.
• Lower Cost: Simpler manufacturing, less material than a double inlet fan of equivalent capacity (though double inlet can handle higher flow).
• Easy Maintenance: Single shaft, single bearing set.

Potential Challenges & Solutions

Common Models / Standards

• Standard: JB/T 8689-2016 (Centrifugal Fans for Ventilation) – but modified for corrosion.
• Typical Models: 9-19 (High Pressure), 9-26 (Medium Pressure), G4-73 (Draft Fan).
• Mounting: Coupling drive (2-pole motor + flexible coupling) or direct drive.

Example Specification for a Procurement Inquiry

Item: Single Inlet CFB Boiler Primary Air Blower Fan

• Speed: 2900 r/min
• Flow: 50,000 m³/h
• Pressure: 8,000 Pa
• Impeller: 304 Stainless Steel, backward curved
• Casing: Q235 + 2mm Epoxy coating (Novolac)
• Shaft seal: Purge air + labyrinth
• Motor: 160 kW, 2-pole, IP55, F-class insulation
• Accessories: Inlet box (with adjustable damper), vibration sensors, manometer ports.

Recommendations for Purchase

1. Confirm the location (PA, SA, or ID fan): ID fans need the most anticorrosion.
2. Request a "Material Certificate" for the anticorrosion coating (e.g., ISO 12944).
3. Ask for a "Vibration Report" after balancing (especially at 2900 rpm).
4. Check the "Spark-proof" design if handling coal-rich air.
5. Ensure the brand has CFB boiler experience (e.g., Shandong Tianren, Yilun Fan, or European brands like FläktGroup / Woods).

Summary: This fan is a high-speed, high-pressure industrial blower specifically designed to handle corrosive flue gases and abrasive fly ash in a CFB boiler. The 2900 rpm speed gives it a compact footprint but requires robust dynamic balancing and wear-resistant materials.