Pumparound flows through a preheat exchanger and after that passes through a control valve and back into the column. While deciding how much pump should be used, what should we consider?
Condition #1: Reduce the control valve opening, provide the pumparound more residence time inside the exchanger which will cool it down more and then it will return at a lower temperature but with a lower flow rate.
Condition #2: Increase the control valve opening which will allow more flow to be fed back into the column but with a relatively higher temperature.
Which one should we choose?