On the handling of accidents in diesel hydrogenation units
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Everyone, I have only been working with diesel hydrogenation units for a short time. An accident occurred recently; there was no fresh hydrogen available in the unit, so a closed-loop operation was carried out for the diesel unit. Our facility is used for processing catalyzed fuel and straight fuel; the process is roughly as follows: Straight fuel enters reactor R101 after being heated to the required temperature, while catalyzed fuel goes through a heating furnace before entering reactor R102. After that, it moves on to R101 and then to the downstream distillation system. During normal production, the heating furnace goes out because the catalyst reactor releases a large amount of heat. But when an accident occurs, the device stops feeding cut wood and replaces it with straight wood. A problem has arisen: should the heating furnace be turned on at this point, or not? Or is it necessary to light it within a short time frame? Since there aren’t enough people, if it’s not necessary to turn it on right away, then it can be postponed. The experienced teachers in the class also have their own opinions, leaving me unsure what to do. I hope the experts here can advise me: is it necessary to light this furnace, or is it urgent to do so? And what impact will lighting it or not have on the equipment? Thank you!
It’s better not to turn it on; at this time, hydrogen consumption should be minimized in order to maintain system pressure. Not only should this furnace not be used, but the other reactors as well should have their temperatures reduced appropriately. If the pressure in the system drops more rapidly due to the lack of cooling systems for the furnace and other reactors, by the time the hydrogen production unit has resolved the issue, the system pressure may no longer be sufficient to operate the recycle hydrogen compressor; as a result, the diesel hydrotreating process will also have to be stopped entirely.
The heating furnace should normally have a permanent light, so that ignition can be carried out immediately in case of an accident, thereby reducing the time required for circulation.
If the furnace is not turned on, at most, after the hydrogen production unit is restored quickly, it may take longer for the unit to resume feeding with qualified products. When the furnace is turned on, the hydrogen consumption increases, which reduces the operating time of the diesel hydrogenation system; it is very likely that the cycle hydrogen compressor will have to stop working, resulting in a shutdown of the reaction system.
In the absence of fresh hydrogen, the system must be cooled to reduce hydrogen consumption; the system is circulated, and the furnace remains in a steady-state mode with a small number of burners activated. Generally, the reaction ceases when the temperature at the reactor inlet falls below 250 degrees.
I think it depends on how far you plan to take the processing of the device. If it’s no longer possible to ensure product quality, then what’s the point of adding more heating furnaces? If the goal is not to affect production or ensure product quality by simply removing the combustion promoters, then whether to add a heating furnace depends on whether it meets the production requirements.
The entire process must be in a closed-loop cycle by now; quality of the product is certainly no longer a concern. So I really can’t understand why this furnace needs to be purchased