plantprowler
Chemical
- Aug 10, 2013
- 136
I often come across vacuum distillation columns in the fine chemicals industry that have condensors feeding gravity reflux (i.e. not pumped reflux) with an available head of approx. 6-10 ft (i.e. elevation difference between the condensor bottom nozzle & the reflux inlet nozzle on the column) The reflux flow rates are often quite low e.g. 300 Litres per hour
Is there a good way to switch these systems from manual control to a PID ratio controller controlling the reflux? What kind of valves / flow sensors work well with such low flow rates / available heads? The fluids involved are typically non-conductive, organics.
In other words, I'm looking for tips & pitfalls on how to deal with these systems.
Is there a good way to switch these systems from manual control to a PID ratio controller controlling the reflux? What kind of valves / flow sensors work well with such low flow rates / available heads? The fluids involved are typically non-conductive, organics.
In other words, I'm looking for tips & pitfalls on how to deal with these systems.
