Phenomena of riser plugging and treatment methods
Thread Content
Phenomena of riser plugging and treatment methods
The main reasons for choking are low processing load, low reaction depth, insufficient lifting medium, and low microreactivity of the regenerated catalyst, all of which result in an inadequate driving force upward in the lift pipe. When there is a large amount of material in the second reaction zone, the driving force is less than the resistance, leading to choking. It is pointed out that the main measures to avoid choking include controlling the lifting medium at the bottom of the lift pipe, the processing volume, the properties of the raw materials, the reaction depth, the inventory in the second reaction zone, the activity and particle size of the catalyst, as well as ensuring that the linear velocity in the second reaction zone is above 5 m/s.
Phenomena: The pressure in the settler decreases, the total pressure drop in the riser increases, the reaction temperature drops, the pressure drop at the inlet of the centrifuge decreases, and the inventory in the stripping section decreases. Treatment: For a short period of time, pre-heating steam can be used; the nozzle sprays the steam to increase the lifting force. It’s easy to handle. If the time is long: the feed must be stopped. When the riser gets clogged, fluidization essentially comes to an end; it is very dangerous to try to handle the situation without shutting off the feed. .
Isn’t dry catalysis all about fluidization? Treatment: For a short period of time, pre-heating steam can be used; the nozzle sprays the steam to increase the lifting force. It’s easy to handle. If the time is long: the feed must be stopped. When the riser gets clogged, fluidization essentially comes to an end; it is very dangerous to try to handle the situation without shutting off the feed. .