emergency shutdown
Thread Content
Let everyone talk about it, especially those with experience.； When the sour gas is suddenly interrupted and cannot be restored for a long time, and an emergency shutdown is required, what should be done? Of course, you can’t follow the steps, you can’t heat soak it, you can’t restore it. ； Furthermore, is there any good way to take any measures to keep the system temperature from falling for a longer period of time? Try to be as detailed as possible when speaking so that everyone can learn together * ! !
Additional questions: If acid gas is interrupted during production, and the entire system is not shut down such as sulfur blowing, leaving the entire CLAUS system in a closed state, how long can it last to ensure that production can be resumed after the acid gas feed is resumed? Have you ever done this before? In addition, if after the acid gas interruption, a stream of nitrogen gas is maintained to be purged from the combustion furnace to the entire system, can the entire system be kept in a smooth state, and can the acid gas interruption time be extended?
Zhenghe? Is it from Dongying? It seems to be using SSR technology? I'm not very clear about this. We currently use the online furnace process and have encountered this situation. There is basically no problem in getting started quickly. The specific method is to use an online furnace to continue to keep the reactor warm after the shutdown. This time lasts for about 2 hours. The purpose is to drive away the accumulated sulfur in the reactor bed. After that, the online furnace is shut down and the reactor continues to use gas to keep the reactor warm. If the time is relatively long, the reactor can also stop the gas fumes. There is no problem within 24 hours, the reactor bed temperature can basically be maintained at around 200 degrees, and the operation can be started quickly. I remember one time, about 48 hours after the shutdown, normal operating conditions were reached after 6 hours of temperature rise. However, the process of the blending valve is not particularly clear. I think the above experience can be applied. The reactor continues to be fired, and the cross-line of one and two revolutions is used to blow sulfur into the two reactors. After that, the temperature does not drop very quickly.
Our unit once had a plant-wide power outage, causing the entire plant to shut down. The sulfur recovery unit was shut down for about 14 hours, but the temperature was maintained quite well. It returned to normal about 4 hours after starting work. If the acid gas is stopped for a long time (the temperature cannot be maintained), the work must not be stopped according to the normal shutdown steps. The only way to start is with gas sulfur blowing.
Learned! ! ! ! ! ! ! ! ! ! ! ! !
I understand that the emergency shutdown mentioned by Huuzhu occurs when the public engineering system is normal, otherwise the handling methods will be different. Generally, emergency shutdowns are caused by interlock activation (or malfunction). At this time, the reactor goes out, so the measures taken should be to immediately vent nitrogen into the furnace (some introduction devices usually have automatic nitrogen venting protection functions) to protect the burners. Others do not need to be dealt with if the operation can be resumed in a short time (within 4 hours). However, if the time is longer, the water in the condenser needs to be drained and the water in the condenser needs to be kept warm with the steam. Our longest emergency shutdown was over 24 hours. This post was last edited by Clauspolunit on 2009-2-25 08:43 ]
I'm from Dongying. . . I think it is not good to blow nitrogen. As a medium, it is cold and will absorb heat. If blown for a long time, the temperature will drop quickly. It is better to light gas, which can not only keep warm but also blow sulfur. I just don’t know if the bed will catch fire easily or carbon will form. How to control it? 1 ； Start the chimney first, then turn on the furnace to control the temperature to 1200 degrees and the oxygen content <1%, and then blow the bed. 2 ； Directly light the furnace according to the original process and gradually increase the temperature. Which one is better?
http://bbs.hcbbs.com/viewthread.php?tid=398530&page=1#pid2125365 It's okay to keep the system warm for 24 hours. I don't agree with nitrogen injection, which will cause the temperature to drop faster.
But sometimes, once there is an emergency shutdown (especially when the furnace goes out), it is impossible for the reactor to be ignited immediately. If only the acid gas is interrupted, gas burning conditions can be considered, but it should be noted that a small amount of steam should be passed into the furnace at this time to prevent carbon deposition or over-temperature.