In 2013, we exported one set of 110 ton CFB boiler to India, this boiler burns coal mixed with rice husk.
CFB Boiler Installation Site
the rated evaporating capacity 110 t/h
the rated steam pressure 6.5 MPa
the rated steam temperature 485 ℃
feed water temperature 130 ℃
fume exhaust temperature for boiler 135 ℃
blow down ratio ≤2 %
cool air temperature 30 ℃
hot air temperature 144 ℃
the design thermal efficiency for boiler 88.08 %
(Ca/S 2.2)desulphurizing efficiency ≥85%
the mixed fuel consumption 23136.1 kg/h
the coal consumption 16195.27 kg/h
the rice husk consumption 6940.83 kg/h
Compared with coal, biomass fuel, if only consider from the boiler itself, there is no much advantage. In India, coal fuel is in short supply, while, biomass resource is rich, so the biomass circulating fluidized bed boiler or co-combustion biomass & coal fuel CFB boilers are used in India industries.
Circulating fluidized bed combustion is a new highly efficient, low emission and coal cleaned technology, its main feature is that the boiler furnace contains a lot of material, which is carried to the upper chamber in the combustion, through the separator arranged in furnace outlet, the material and gas separated, and sent back to the bed material through the non-mechanical valve, combusting circularly for several times. Thus the fuel in CFB boiler is fully burned and high burning efficiency. Even low grade or bad quality fuel (coal, biomass) is available.