This biomass-fired stoker was not performing as expected. Intense, swirling flames along the membrane wall pointed to a combustion-air distribution problem at the edge of the fuel bed.
The assessment identified failed side-seal assemblies. Age-related deterioration contributed, but the original arrangement also failed to accommodate the required movement adequately. Air bypassing the fuel bed affected local combustion and bed consistency.
The corrective work combined three changes: replacing the side-seal assemblies, re-establishing the cold reference offsets so the system expanded into the intended position, and reducing undergrate-air pressure to improve seal performance and bed consistency.
Those changes addressed the seals and the conditions around them together. Replacing damaged parts alone would leave the plant exposed to the same air-distribution and thermal-movement problems.
CPE evaluates solid-fuel combustion systems as an interaction between fuel delivery, the bed, air distribution and mechanical condition. Consistent fuel metering is another part of maintaining the intended bed conditions.