Quench column bottom level cascade to top reflux
Quench column bottom level cascade to top reflux
(OP)
Does anyone has experience in bottoms level cascade to top reflux in distillation column control? The current plant setup is the top reflux drum level cascade to distillate product flow. Column bottom level cascade to top reflux. I haven't seen this kind of setup. I think it can cause the column unstable using bottom level to control top reflux. Any comment on this? Thanks





RE: Quench column bottom level cascade to top reflux
RE: Quench column bottom level cascade to top reflux
If bottoms flow MUST be on flow control, I would consider controlling bottoms level with reboiler heat. This works only when you have an adequately high boilup to bottoms flow ratio, however, as in a tower which also has a high reflux ratio. Otherwise, bottoms level should be cascaded to bottoms flow.
RE: Quench column bottom level cascade to top reflux
RE: Quench column bottom level cascade to top reflux
U. Mathur and R.J. Conroy: "Successful multivariable control without plant tests", pages 55-65, Hydrocarbon Processing (June, 2003).