I am looking for books or materials that provide a detailed explanation of the initial process of driving a plant; for example, how is the initial liquid level in the tower established when starting operation?
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I work on chemical process design, but I’m not very familiar with the aspects related to the operation and startup of chemical plants. I’d like to learn this systematically – for example, what are the steps involved in starting up a unit plant after feeding it with raw materials for the first time? How were the initial temperature and pressure established? How is the initial liquid level in the tower established while driving? When the equipment or unit is shut down urgently, or during routine maintenance, is it necessary to empty the materials in the system for the disconnected equipment or system? Wait. Dear experts, please help by informing me about books or materials on this topic. Thank you first~~
You can first take a look at these books in this cloud storage link: https://yunpan.cn/cux3J3nYeG89U. The access password is 39f5
I have been in a factory. It is mainly the thermal method used for the production of polyphosphoric acid. In the process, after yellow phosphorus is burned, the flue gas passes through the primary absorption tower, the secondary absorption tower, the Venturi scrubber, the tertiary absorption tower, and the fiber mist eliminator before being discharged. To start up the empty unit, water is added to the circulation tanks of the first, second, and third absorption towers; thereafter, the pumps are started for circulation. Once the liquid level remains stable on the DCS, phosphorus is added for ignition. At this time, since it is Qing Shui driving, the fluid from level 1 will flow towards level 2, and that from level 2 will flow towards level 3; therefore, it is necessary to enable the flow from level 3 back to level 2 and from level 2 back to level 1 in order to maintain stability. Once the phosphate concentration increases, gradually reduce it by switching from stage three to stage two, and then from stage two to stage one. It gradually stabilized! This is a process that has been seen in production. During the shutdown process, it is necessary to first lower the liquid levels in the primary, secondary, and tertiary circulation tanks before shutting down, in order to prevent the liquid remaining in the tower from flowing back into the circulation tanks and causing acid spillage. In the case of a short-term emergency shutdown, pressure is usually maintained in the boiler drum first (to ensure availability for preheating the pipelines when restarting), after which phosphorus feeding is stopped, while the pump continues to operate. If it is necessary to stop the pump, lower the level of the circulating liquid first before stopping it. This is the method I’ve seen in the factory.
Thank you, I took a look – none of these books cover anything related to driving operations.
There are no ready-made answers to these questions in books; you just need to ask an experienced expert and you’ll find out. If condensate can be used, establishing the liquid level in the tower before starting up usually requires the addition of condensate; if condensate is not available, some process materials need to be prepared for startup.