1. Immediately stop the coal feeder, the secondary fan, the primary fan and the induced draft fan. If the boiler tube bursts, the induced draft fan may not be stopped temporarily in order to exhaust large amount of steam and to prevent the corrosion of heating surface and the boiler wall from absorbing large amount of moisture and causing damage; If large area of the fluidized bed cokes, the primary fan and the induced draft fan may not be stopped temporarily in order to cool and protect the vent cap and to prevent the fuel from melting at high temperature and blocking the vent cap hole and bringing larger workload in maintenance. After the bed temperature drops to below 550 ℃, stop the operating of the fans. 

2. Close the main steam valve, open the draining valves in front of the superheater and the steam cut-off valve. 

3. After stopping water feeding, then open the recirculation valve, strictly monitor the water level. Adjust timely according to water level( in severe water shortage, it is strictly prohibited to feed water to the boiler in order to prevent the boiler tube bursting and deformation). If the amount of leakage of the coal economizer is greater than 40 t/h, the recirculation valve may not be opened, but the water level must be kept normal. 

4. After emergency shut-down of the boiler, close the dosing valve and the continuous blowdown valve to drain out the ash inside the returns feeder at both sides. If the boiler pipe inside the hearth leaks seriously, the bottom materials in the hearth shall be emptied and the slag-discharging valve shall be fully opened. (in order to prevent the bottom materials bonding and bringing difficulty to the cleaning work).  

5. After the boiler is stopped, stop the electrostatic precipitator, but the pneumatic ash conveying system shall be kept operating to discharge the ash accumulated thoroughly. 

6. Other operations can be carried out according to the normal operation of the boiler. 

7. Record the boiler stopping time, causes, operating items and sequences in detail in the shift record book and report the causes of accident to the superiors in time. 

8. On condition that feeding water to the neighboring boiler is not affected, feeding water to the boiler can be ensured, the boiler never must not be fed due to leakage(except serious shortage of water).