Phenomena, Causes And Treatment Methods When The Boiler Is Full Of Water
Phenomena, causes and treatment methods when the boiler is full of water
First: Phenomenon
1. The water level is invisible or absent, and the high water level alarm;
2. When the steam temperature decreases, white steam can be seen in the main steam isolation valve of the boiler and the inlet valve of the steam engine;
3. Water impact of steam turbine or steam pipeline;
4. The feedwater flow is abnormally larger than the steam flow.
Second: Reason
1. The automatic tripping of water supply is manual, resulting in the abnormal increase in water supply;
2. The safety valve on the steam drum or steam header acts, causing the water level to rise or bring water;
3. The boiler’s evaporation capacity is overloaded, and steam water co-transpiration occurs.
Third: Treatment method
When the boiler steam pressure and water supply pressure are normal, and the drum water level rises above +50mm, the following measures should be taken:
1. Compare and flush the two water level gauges to check whether their indications are correct.
2. The water supply regulation is changed from automatic to manual. Close the manual water supply valve and turn down the main regulating valve to reduce the water supply.
If the water level in the drum is still rising after the above treatment and exceeds +75mm, the following measures should be taken:
1. Open the emergency drain valve of the steam drum and close it immediately when the water level reaches the normal level.
2. According to the steam temperature, turn down or close the desuperheating water valve, and open the drain valve of the main steam pipe and the drain valve of the superheater.
After treatment, the water level of the steam package continues to rise. When the water level exceeds the visible water level on the upper part of the steam package water level gauge, the boiler should be shut down in an emergency, disconnected from the main pipe as soon as possible, stop water inflow immediately, open the recirculation valve, strengthen boiler drainage, pay attention to the appearance of the water level on the upper part of the steam package water level gauge, and close it after the water level reaches the normal level. After the standby furnace is normal, it can be heated by the hot furnace.
If the water level cannot be seen in the drum water level gauge and is not found in time, the following measures should be taken:
1. Compare and flush the two water level gauges to check whether the indication is correct. Open all the drain valves of the drum water level gauge, and then slowly close the drain valve. If there is a water level in the water level gauge and the water level gauge continues to be filled, it is proved that the boiler water level does not exceed the steam side pipe of the water level gauge, and it should be treated as an emergency shutdown.
2. Open the drain valve of the water level gauge and slowly close the drain valve, and the water level cannot be seen in the water level gauge. To confirm that the water is seriously full, close the steam water valve, open the drain valve, drain the water in the water level gauge, and close the drain valve immediately. Quickly open the steam valve water level gauge slightly and fill it with water. At this time, it can be determined that the water level exceeds the steam side pipe of the steam water level gauge. It should be treated as an emergency shutdown and disconnected from the main pipe as soon as possible.
3. In case of a water level accident in the boiler, if it is difficult to judge the water level, the boiler shall be shut down immediately. After the boiler is shut down, call water by calling water and check the water level of the steam drum.