How to operate fractionation when the reaction depth changes? Looking forward to your reply online! !
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If the reaction depth increases while the reaction pressure remains constant, will the flow rates of each fractionation stream, or the reflux temperature, increase or decrease? If the reaction depth increases and the reaction pressure rises, how should the distillation and reflux processes be carried out?
In my opinion, if the reaction pressure is kept constant, the reflux rate should be increased; if the reaction pressure rises, the reflux rate should be decreased
Hehe, this is tricky. It depends on how you understand it. What is the reaction? Are there no process specifications? Will the reaction pressure increase? And not control it? How can the products you produce be of qualified quality then? Negative reactions will keep increasing. It can’t be explained in just a word or two.
Agree with the view from the 3rd floor. What kind of setup is the original poster using? How can increasing the reaction depth be achieved if the reaction pressure keeps fluctuating? It’s difficult to maintain reaction equilibrium, and it’s also hard to determine the optimal operation parameters for the distillation tower.
LZ’s question is confusing. If you really want to solve the problem you’re facing, you should provide more detailed information when asking questions, so that other users can offer their opinions or specific solutions. For example, what kind of device is it? What process to use? Is the change in reaction depth due to the later stage of catalyst use or changes in plant load?
Given the high degree of reaction, increase the reflux rate appropriately to keep the top temperature at or below 140 degrees, or control it according to the requirements regarding the dry point of gasoline; reduce the temperature of naphtha returning to the tower as appropriate to ensure the appropriate temperature for diesel extraction. At the same time, adjust the liquid level and temperature at the bottom of the tower based on the extent of the reaction
Changes in the reaction depth alter the feed composition for distillation. Adjusting the reflux rate in the distillation column depends on the temperature distribution within the column; if the temperature of the trays in the rectification section increases, the reflux rate can be increased appropriately, while if that temperature decreases, the reflux rate needs to be reduced. In short, the reflux rate in the distillation column is adjusted based on its temperature distribution.
For catalytic cracking units, make adjustments according to the suggestions from Floor 6; for other units, refer to the suggestions from Floor 7. The principle is to prevent abnormal tray phenomena such as tower flooding and maintain high separation efficiency.
The reaction depth is large, which results in a greater amount of small-molecule gas and heat entering the distillation tower. To maintain thermal equilibrium in the distillation tower, it is necessary to increase the amount of heat recovered through reflux; to keep the reaction pressure constant, it is required to increase the power output of the gas compressors. The same is true in reverse. The backflow temperature you mentioned is adjusted through circulating water cooling and heat exchange with a heat exchanger.