The liquid level in the reflux tank is controlled by the reflux flow rate
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Experts, in our design we use the reflux flow rate to control the liquid level in the stabilizer reflux tank, and we use the production volume to control the temperature at the top of the stabilizer. Is this reasonable? ? ? What are the benefits? ? Can the tower top temperature be maintained this way? Will there be a delay?
The opposite is true: reflux flow should be used to control the temperature at the top of the stabilizer, while the amount of product taken out should be used to control the liquid level in the stabilizer’s reflux tank. Contact the instrument panel to have it changed.
I checked online and indeed there is such a new method of adjustment; there are papers available online stating that it is used to maintain the reflux ratio. It’s hard to understand though, and in such a system, all the top reflux tanks use the reflux flow rate to regulate the liquid level.
We’ve really never used this method either; we control the tower top temperature through reflux flow, and we control the liquid level in the reflux tank through the output flow
Generally, the reflux flow is used to regulate the tower top temperature; however, in this design, it is the reflux flow that is used to adjust the liquid level in the reflux tank!
Will this control method have a long delay time? However, the control might be quite stable.
Control is possible, but due to fluctuations in the liquid level of the reflux tank, it is necessary to adjust the PID settings of the control valve. This type of control is only theoretical; it becomes difficult to make adjustments when the properties of the liquefied gas change or when the yield varies
There is a paper titled \"A Completely New Level Control System for the Reflux Drum in Distillation\", which describes how this system ensures stable liquid levels, allows for easy adjustment of the reflux ratio, yields good distillation results, and provides stable operation; it’s actually the first time I’ve come across such a system.
For the stabilizer in an aromatization unit, its properties are unlikely to change significantly; if it’s a vacuum distillation unit, this approach probably won’t work
We also use the reflux flow to control the tower top temperature, and the output flow to control the liquid level in the reflux tank
“\"Using reflux flow to control the liquid level in the stabilizer reflux tank\" – is it then easy to control the temperature at the top of the tower?