Catalytic self-preservation problem

If the main air check valve functions properly and the bed can be sealed successfully, then there’s no major problem. But if the main air check valve doesn’t work well, the catalyst will flow back into the booster; such things have already happened

There are two advantages to using it: 1. It prevents the catalyst from flowing back into the booster when the damping check valve cannot be closed； 2. For coaxial catalysis, it is convenient to transfer the catalyst from the stripping section to the regenerator.

I’m not sure what type of process the original poster is referring to. In our case, the pressurized air backup system for the two-stage overlapping regeneration process has always been in use. After the booster machine stops operating, activating this backup system allows some of the main air flow to be directed to the outlet of the booster machine, thereby keeping the heat exchanger in a fluidized state and preventing it from becoming dead. This may affect normal operation but does not result in a shutdown; by adjusting the amount of material processed and the air flow, it is possible to continue operating until the backup machine can be brought online. If it is a tandem high-low type booster that stops, then production has to be halted.

It should be used for two purposes: one is to prevent the catalyst from flowing back, another is to avoid blockages in the pipes, and also to ensure stability throughout the reaction and regeneration system so as not to cause excessive disruptions

I fully agree with what everyone has said; we should keep it in semi-automatic mode to prevent the catalyst from flowing back into the booster and to avoid any fluctuations in the booster from affecting the main air system

We didn’t activate any of our self-protection systems, (except for the unit lubrication self-protection and displacement protection). The entire device was removed; the key issue was that the management did not trust the reliability of the instruments.

The booster pump of our company’s heavy oil catalytic unit is not currently in use; primary air is used for fluidization instead. The unit achieves very good energy-saving results, and the self-protection system is not activated either. Using a one-way damping valve for the primary air yields good results.

It is sufficient to add a bypass line on the main air duct connected to the pressurized air duct; when the pressurizer stops operating, the bypass valve will open automatically.

The main function of the pressurized air self-protection system is to prevent catalyst backflow, which could damage the equipment and clog the pipelines. From the perspective of standardized management, device self-protection systems should be put into use, and there are no issues with the reliability of such self-protection systems.

We don’t use a booster; instead, we utilize compressed air as the air for fluidization and transportation purposes, thereby extracting heat from it. The advantages of this approach are: reduced number of devices, easier centralized management, and prevention of catalysts from flowing back into the booster. Nice! During the major maintenance in 2008, the booster was finally removed completely. Regarding the self-protection system, I believe it’s better to be cautious; after all, the reactions involved are unpredictable, and there are many situations that cannot be forecasted with certainty. This is especially true regarding the impact of external materials and equipment failures. By activating the self-protection system, at least an additional layer of protection is provided. Of course, what’s most important is to remain careful and attentive. As maintenance personnel, one must constantly monitor the status of the self-protection system and the reasons for its activation, in order to address any issues promptly. At the workshop level, it may be possible to bypass certain components of the raw material self-protection system depending on the process requirements, but the main air supply self-protection system must always be active