Experience in operating the device when it is restarted after being shut down

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After the unit is restarted, since the conversion system is at the beginning of the entire process and involves many utility systems, desalinated water and steam are the first to be restored to operation. At this time, special attention should be paid to the liquid levels in the large and small steam drums, especially when taking readings. Both of these drum levels are equipped with interlocks; if these interlocks activate, it will cause the entire system to shut down. During this startup, I was occupied with taking readings that day, so I didn’t pay much attention to the liquid level in the large steam drum. By the time I noticed it, the liquid level in the drum had dropped below 20%, and the pressure had risen significantly. Due to the large fluctuations in drum pressure during the startup phase, the three-element automatic control system was not activated; moreover, the speed of the boiler feed pump was also low. Everything had to be adjusted manually. Therefore, the water supply flow rate was also below the interlock value due to the low pump speed and high drum pressure. Fortunately, that interlock was not activated at the time, and the issue was detected in a timely manner. By increasing the pump speed and opening PCV-13 to reduce the drum pressure, a serious accident such as a dry drum condition was avoided. In the future, during the startup phase, especially when taking readings, two people should coordinate with each other and must not be careless. During startup, as there are many people involved and the shift leader has a lot of tasks to handle, I need to pay even more attention to monitoring the liquid level promptly. Interlocked shutdowns or a dry drum in the steam drum must never occur.