How long does it take to shut down a distillation tower and wait for the liquid in the trays to dry up?
Thread Content
As a student, I don’t quite understand these specific processes; for now, I’m using Aspen Dynamic to simulate the entire parking process. It is not clear at present, when a distillation column is shut down and liquid discharge is carried out, whether it is necessary to wait for the liquid in each tray of the column to flow slowly down to the bottom one by one. Experts, how long does this process of liquid leakage generally take? For example, if there are 100 trays, how much time will it take for this process to complete? This should be related to the design of the tray; please tell me everything you know~ How much time does it take to manufacture a tray, roughly? Thank you all for your guidance! !
I guess no one can give you an exact answer to this question. The time it takes for the liquid to reach the bottom of the tower depends on the composition of the substances in the tower, their boiling range and enthalpy, as well as the temperature at the bottom of the tower when operation is stopped. It is also influenced by the timing at which bottom heating is turned off and the duration of the cold reflux period.
This is not a fixed value; it depends on the rate of steam temperature reduction at the bottom of the tower when you park the system, the temperature of the tower, and the reflux flow rate.
Thank you; it turns out the situation is quite complex. Then, if there’s no gas coming up, the leakage should resolve quickly, right? Could you roughly explain to me what the process is like when a distillation tower is shut down? How long does it take to park in a large tower with 100 spaces? Just give me a range.
Oh, is over 10 hours reasonable?
Also, can the pressure be reduced before the liquid is drained?
By reducing pressure, do you mean reducing the heat load, increasing the cooling at the top of the tower, or increasing the reflux flow – how exactly is this reduction achieved? Actually, these are all measures to reduce pressure when parking; in any case, they need to be considered in conjunction with the operating conditions. Simply put, when you stop the vehicle to reduce load, it is a process of lowering voltage.
It won’t take long; depending on the volume of work, it can be completed within 2 hours if handled properly.
Okay, I get it. In other words, whether it’s reducing fever or increasing blood return, both will cause a certain decrease in blood pressure, right? In other words, when there is still liquid in the tower, the pressure drop caused by these methods is normal – can it be understood that way?