Issues with the use of accident cooling water
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Is the accident quench water used only when the quench water flow rate drops to the interlock value, or is it activated even when the flow rate has not yet reached that interlock value?
It is activated in parking and accident conditions; a chilled water flow rate as low as the interlock value indicates an accident condition. Those who know the answer, please reply.
In the event of an accident, the quench water valve opens automatically when the flow rate of quench water drops to the set value, or it opens automatically in case of a loss of instrument air.
Emergency cooling water is used in emergency situations; in other words, it is employed when the cooling water supply cannot be maintained continuously and in sufficient quantities due to any reason. Low, very low, and even lower level interlocks do not represent emergency situations.
If the flow rate of the quench water drops too rapidly or is insufficient, the emergency quench water system is activated automatically in order to prevent the downcomer from being damaged
When the flow rate of the quench water is low, the standby pump starts automatically; when it drops even further, the emergency quench water valve opens；
The emergency quench water is activated automatically when the amount of quench water falling below the set low-low interlock level, thereby preventing the quenching ring and downcomer from being damaged by high temperatures. The valve for emergency quench water is designed as an FO valve, meaning it will still open even in the event of a loss of instrument air
In our company, the emergency quench water circuit is always kept in bypass mode; when the load on the gasifier is high, the emergency quench water flow is increased slightly to raise the liquid level in the gasifier. This is done to prevent blockages in this pipeline, as the water quality in our company’s system is poor.
The accident quench water can be used when there is a significant decline in the quench water flow rate, and it becomes necessary to use it to ensure the operation of the gasifier, which involves manually activating it. When the gasification furnace stops operating unexpectedly, if the flow rate of the quench water continues to drop to a certain set value, the emergency water valve will open automatically to protect the quench ring and the downcomer.