Distillation reflux
Thread Content
In the distillation process, what is the difference between direct tower top reflux and reflux via a reflux pump?
It seems that nowadays many systems use recirculation pumps to force the recirculation; forced recirculation allows for better control of the recirculation ratio, while natural recirculation doesn’t seem to work as well.
This post was last edited by limingshuguang on 2010-1-15 21:57. The natural backflow resistance is high, and there are requirements regarding the height difference between the outlet pipe and the backflow pipe. There is a question: how does a distillation column use pumps to control the reflux ratio?
The reflux in the distillation column of Sichuan LeDian TianWei is forced reflux, and the condenser does not necessarily need to be installed at the top of the tower. This is what I understand! The advantages of other forced returns are not very clear!
One is forced reflux, and the other is natural reflux. The advantage of forced reflux is that it allows for easy adjustment of the reflux ratio, making the operation of the distillation tower more convenient ； Natural backflow imposes high requirements on factors such as potential difference, pressure, and the installation location of instruments. Our company uses natural backflow, but the flow is often unstable and difficult to control!
I agree with the points mentioned on the third and fourth floors; putting them all together provides a very comprehensive answer.
The pump backflow is forced backflow; the flow rate in the pipeline after passing through the buffer tank and the pump remains relatively stable, and it is also easy to control the flow rate using a control valve.
3# jukejuke: Control valves and flow meters are installed on the pipeline
When using a pump for forced reflux, other impurities such as C may be introduced, while it is difficult to control the reflux ratio with natural reflux, which requires a sufficiently high pressure difference. At present, Xinguang uses natural reflux, but the reflux effect is not very good; Letian Tianwei uses forced reflux, which is said to be an improvement based on Xinguang’s method.
The two methods make no difference in the manufacturing process or product quality; the difference lies in the level of investment and operating costs. – Self-reflux: the tower is not very tall. – Forced reflux: used in larger installations with taller towers.