Regarding the lining baking issue in the catalyst transfer line of FCC units, what are some good suggestions on how to ensure the proper temperature?
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As the title indicates, the MIP process features the following external circulation pipes and internal linings: 1. Raw catalyst external circulation pipe (from the stripping section to the second reactor); 2. Regenerated catalyst external circulation pipe (from the second regenerative turbulent bed to the first regenerative rapid bed); 3. Raw catalyst inclined tube; 4. Regenerated catalyst inclined tube; 5. External heat exchanger inclined tube; 6. Mixed inclined tube for cold and hot catalysts. Short circuits can occur in these components, so in new installations, the manufacturers pre-assemble them, and they are installed on-site after baking. Issues: 1. Seams are inevitable during installation, and these seams need to be filled with lining material A0. During the actual baking process, due to the small diameter of the catalyst delivery pipes and high pressure drops, short circuits can occur. How can the quality of baking be ensured? 2. After maintenance and the lining is repaired again, how can the baking quality be ensured?
Open the valve to be controlled, then the other valve, the vent at the top of the settler; open the slide valve of the external heat exchanger and the vent at the bottom of the external heat exchanger. However, it’s basically impossible for the settler and the external heat exchanger to reach the temperature specified by the lining material – 350 degrees would already be quite good
Doing the work of lining things up is actually quite simple, but it’s not very practical to take everything into account. The key is to adjust the opening here to be larger appropriately, depending on the area that needs to be heated the most – that’s usually all that’s needed!
Is there a vent on the catalyst transfer inclined tube? It seems that only the backflow instrument air used to measure pressure drop can be used; with a orifice plate diameter of 2 mm, it cannot meet the requirements for baking the lining
Follow the heating curve strictly when raising the temperature. In fact, even if this is done meticulously, the lining will still peel off during the next maintenance session; after all, it’s not as good as the original one, and even if some of it is damaged, more of it will still peel off. So, if possible, check for those that have already come loose or are about to come loose, and smash them as well before applying it again
The key issue is that the temperature required by the heating curve cannot be reached
Smash it, re-line it, but if the temperature during baking isn’t high enough, won’t it crack and come off again?
This post was last edited by Refiner on 2016-7-7 14:04. The temperature requirements for various sections can be met by adjusting parameters such as pressure, slide valve opening, vent opening, and air flow rate.