It has been nearly a decade since the Instrumentation, Systems and Automation Society (ISA) introduced S88, its first standard for batch control systems. Its still integral in optimizing operations today.
Management always strives to increase the corporation's long-term value to its owners. As a result, it is very important to understand how they assess potential investments to get your project approved.
Install a flow meter in the recycle, cascade the flow set point with a pressure control loop. With proper tuning, the valve characteristics are lost in the flow control loop, which should be tuned fast with PI.