The furnace and the two sides of burner zone of ZG’s biomass CFB boiler adopts membrane water-cooled furnace structure, the boiler grate adopts double layers or single layer layout structure. It is important for us to know how to maintain the boiler’s high efficiency.
In high capacity pulverized biomass CFB boilers, the total losses account to about 12 to 14%, i.e. 86 to 88% boiler efficiency. Roughly 50% of the losses can be tuned to the optimum and the other 50% is governed by fuel properties like hydrogen in fuel, moisture in fuel, and ambient air conditions.
The best efficiency in the boiler can be achieved if the losses are kept to the minimum. Since 50% of the losses are dependent on the fuel and ambient condition, the best efficiency can be achieved by properly tuning the other 50%, i.e. mainly carbon loss and dry gas loss.
1）Keep an optimal excess air level, generally about 20% in a biomass CFB boiler
2）Tune combustion of fuel to the optimal condition.
3）Understand the fuel being fired
4）Proper distribution of combustion air at primary, secondary, and tertiary levels
5）Keep the required fineness of coal about 75% through 200 mesh and less than 2% on 50 mesh sieve
6）Keep the maximum mill outlet temperature to reduce air bypassing air pre-heater
7）Soot blowing the entire heat transfer surface at an optimal frequency
8）Minimize the air in leakage to the boiler