ZG CFB boiler is designed for customers, who use the boiler fuel with wide range, different characteristics. It has some special designs. For example, superheater is a excellent part of the CFB boiler.Because part of the CI in biomass fuel must transformed into HCL and CI2, avoiding superheater deposit deposit or ash is an effective measure to reduce the extent of corrosion in superheater, which is caused by the interaction of alkali metal salt, CI2 and HCL. This series of boilers use platen superheater as its high-temperature superheater to essentially avoid deposit or ash in superheater, elimater one of the reasons that might cause the corrosion to the high-temperature superheater. Circulating Fluidized Bed combustion has given boiler and power plant operators a greater flexibility in burning a wide range of coal and other fuels. All this without compromising efficiency and with reduced pollution. How does the CFB boiler work?
At the bottom of the CFB boiler furnace there is a bed of inert material. Bed is where the coal or fuel spreads. Air supply is from under the bed at high pressure. This lifts the bed material and the coal particles and keeps it in suspension. The coal combustion takes place in this suspended condition. This is the Fluidized bed.
Fine particles of partly burned coal, ash and bed material are carried along with the flue gases to the upper areas of the furnace and then into a cyclone. In the cyclone the heavier particles separate from the gas and falls to the hopper of the cyclone. This returns to the furnace for recirculation. Hence the name Circulating Fluidized Bed combustion. The hot gases from the cyclone pass to the heat transfer surfaces and go out of the boiler.
To start with the bed material is sand. Some portion is lost in the ash during the operation and this has to be made-up. In coal fired boilers the ash from the coal itself will be the makeup material. When firing biomass fuels with very low ash content sand will be the makeup bed material. For high Sulphur coals Limestone addition to the bed material reduces SO2 emissions.
ZG CFB boiler has been wide range used. The superheater is very outstanding. It is the model among coal fired boiler.