The starting procedures of the air fans is: the induced draft fan ---- the primary air fan --- the back-feeding air fan --- the secondary air fan
Start the induced draft fan
--- During the starting period of the boiler, the induced draft fan is the air fan which is firstly started in the circulating fluidized air and flue system. Before the induced draft fan is started, the inlet baffle should be set at the minimum position to avoid the overload current of the induced draft fan motor during the starting period. Once the induced draft fan is started, note that the vibration indicator of the air fan bearing, the voltage, the current value and the temperature should within the specified scope. Open the control baffle of ID inlet vane slowly and make the furnace negative pressure to be automatically controlled, monitor the furnace pressure and then adjust the control baffle, so that the appropriately furnace pressure would be get at the exit of the combustion chamber.
--- During the operating period of boiler, if the induced draft fan stopped working, whatever the reason is, the primary air fan, the secondary air fan and the feeding system would also stop working.
Start the primary air fan
 --- During the starting period of boiler, the starting of the primary air fan should be after of the starting of the induced draft fan. And before the starting, the inlet baffle of air fan, the downstream primary duct damper and the duct dampers of the start-up burner should be adjusted to the minimum position, so that the overload of the air fan motor can be avoided during the starting period.
--- Once the primary air fan is operated, open the control damper of the inlet vane for the primary fan slowly to monitor the furnace pressure.
The starting of the back-feeding air fan
--- During the starting period of boiler, once the induced draft fan is started already, start the back-feeding air fan and check the air flow of the back-feeding air box. And during the normal operating period, the back-feeding air pressure should be maintained to be 14000Pa. The temperature of the back-feeding leg must be monitored by the operators, so that the appropriate circulation rate of bed material in the combustion chamber can be ensured.
The starting of the secondary air fan
--- Before the secondary air fan is started, make sure the inlet damper of the air fan is closed, so that the overload of air fan motor can be avoided.