The Roots blower of the boiler is mainly used to provide stable and high-pressure airflow for the boiler system, supporting key functions such as combustion, ventilation, or flue gas circulation. Here are its specific functions and working scenarios:
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**1. Core functions**
-* * Combustion air supply**
-Deliver primary air (fuel mixing) or secondary air (combustion assistance) to the boiler burner to ensure full combustion of the fuel and improve thermal efficiency.
-High pressure characteristics: Roots blower can overcome furnace resistance and provide stable air supply (especially suitable for scenarios requiring high-pressure air supply such as biomass boilers and gas boilers).
-Flue Gas Recirculation (FGR)**
-Extract some of the flue gas back to the combustion zone to reduce oxygen concentration and combustion temperature, decrease NOx (nitrogen oxide) emissions, and meet environmental protection requirements.
-Positive pressure ventilation**
-Maintain a slight positive pressure in the furnace to prevent cold air from infiltrating and affecting combustion efficiency, or to avoid negative pressure causing smoke leakage.
-Pneumatic ash conveying (some boiler systems)
-Provide power airflow for the transportation of fly ash and particulate matter.
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**2. Why choose Roots blower? (Compared to other fans)**
|* * Requirement scenario * * | Advantages of Roots blower * * | * Limitations of alternative solutions (such as centrifugal fans) * *|
|----------------------|------------------------------------------|--------------------------------------|
|Stable flow rate and high-pressure air are required | Flow rate is less affected by pressure changes, suitable for high resistance systems | Flow rate is prone to fluctuations and efficiency decreases under high pressure|
|Frequent start stop or load variation | Sturdy structure, resistant to frequent operation | Large impeller inertia, slow response|
|Small flow rate, high pressure | Volumetric design, easy to surge under low pressure head | Low efficiency when low pressure head is still present ||
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**3. Typical Application Boiler Types**
-Gas/oil fired boiler: Provides combustion air to optimize combustion efficiency.
-Biomass boiler: High pressure air required for transporting high-density biomass fuel.
-Circulating fluidized bed boiler (CFB): Supports fluidized air system to maintain bed material fluidization.
-Coal fired boiler: auxiliary flue gas recirculation or fly ash conveying.
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**4. Operation precautions**
-Overload prevention: The exhaust valve or pressure relief device must be functioning properly to avoid damaging the motor due to excessive back pressure.
-* * Anti clogging * *: The imported filter needs to be cleaned regularly to prevent foreign objects from entering and damaging the rotor.
-Lubrication maintenance: Synchronous gears and bearings need to be regularly lubricated to reduce wear.
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**5. Fault impact**
-* * Shutdown consequences * *:
-Insufficient combustion, black smoke emission, and decreased efficiency.
-Imbalance of furnace pressure may trigger interlock shutdown.
-Excessive smoke emissions (such as increased NOx).
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**Summary: Boiler Roots blower is a key equipment to ensure combustion efficiency, environmental emissions, and system stability, especially suitable for scenarios that require high pressure and constant flow. The maintenance focus is on pressure monitoring, sealing inspection, and regular lubrication.
