Our reflux apparatus consists of a centrifugal pump and a flow control valve.  The pump generates 60psia upstream of the valve.  The downstream pressure is 15psia.  Not wanting a 45psi pressure drop across the valve, I sized the valve for a 5psi pressure drop.
I would expect your reflux apparatus to include piping and fittings, changes in elevation etc. in addition to the centrifugal pump and control valve.  What was the basis of selecting a pump that produces 60psia head upstream of the valve?  Perhaps it was a pump that was available and you can waste 45psi pressure drop across the valve.  Consider the piping hydraulics.
You should have no problem selecting a control valve to handle the full pressure drop.  However the capacity calculation for the control valve should consider the minimum pressure differential.  Thus you still need to know the other pressure factors.

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