[E-book] Hydrogenation Unit Studies* Notes – Chapter 3 Discussion Forum on Fractionation Systems
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This post was last edited by 955559 on 2017-6-9 at 13:50. Chapter 3: Fractionation System. This is a discussion thread for [E-book] Notes on Hydrogenation Units – Chapter 3; discussions related to the content only are allowed. Any unrelated posts should be removed at the moderator’s request. Main contents of this chapter: 1. Operation of the stripping tower (hydrogen sulfide removal tower): 2. Operation of the distillation tower: 3. Quality standards and control for diesel: 4. After the plant is shut down for cleaning, in order to remove impurities from within the towers, should the manholes be accessed from top to bottom or from bottom to top? Why? 5. Why is it necessary to add corrosion inhibitors to the top of the stripping tower? 6. What are the phenomena, causes, and solutions for tower flooding? 7. What should be done after a safety valve activates? 8. What are the symptoms of oil in the fuel gas? How to deal with it? 9. What are the principles for using heat exchangers? 10. How to cut off the heat exchanger? 11. What precautions should be taken when using a heat exchanger?
1. Pay attention to the steam-to-fuel ratio. 2. Monitor the temperatures at the top and bottom of the tower as well as the tower pressure. 3. The flash point can be determined from the temperature at the bottom of the tower, while the sulfur content can be determined from the degree of reaction. 4. From top to bottom, safety considerations must be taken into account. 5. The gas contains hydrogen sulfide, which helps to reduce corrosion. 6️⃣ \"Tower flooding\" occurs when the gas load during distillation is too high (there is too much upward airflow); the heavier components in the gas do not have time to cool down before being carried to the upper trays, resulting in a reduced efficiency of distillation or even its disruption. This situation can generally be improved by reducing the feed volume and feed temperature, while also increasing the reflux rate to restore the temperature gradient within the tower. 7. Identify the cause, take corrective action, and then check the safety valve. 8. Cool first, then heat. 10. Heat first, then cool. 11. Prevent pressure buildup in a single layer