Connecting process analyzers to flare stacks

Online process analyzers are often critical to plant performance, however obtaining accurate, repeatable analyzer results requires very stable inlet and outlet flow and pressure control.

By Control Engineering Staff August 21, 2003

Online process analyzers are often critical to plant performance, however obtaining accurate, repeatable analyzer results requires very stable inlet and outlet flow and pressure control.

For years, some companies exhausted analyzer effluents to the atmosphere. However, increasing clean air legislation requires companies to find new ways to reduce or eliminate emissions, including process analyzer effluents. The most straightforward solution is to vent analyzer effluents into a plant’s flare stack header. The problem with this solution is, flare stack headers can experience wide flow and pressure fluctuations that can adversely influence a process analyzer’s performance.

Parker Instrumentation recently introduced its Vent Recovery Panel (VRP), a solution for connecting online process analyzers into flare stack disposal systems. The VRP maintains a constant pressure that protects analyzers from flare stack header pressure fluctuations.

Using patent-pending technology, VRP uses a fast-loop flow controller, and a modular switching system.

VRP’s flow control system uses a combination of flow and pressure regulation elements to maintain constant analyzer inlet and outlet pressure. According to Parker spokespersons, VRP is capable of maintaining pressures to within +/-0.25% of setting during widely varying pressure tests.

For more information, click here , then on the left side toolbar click ”Catalogs-Online,” scroll to the bottom and select Bulletin 4141-VR.

—Dave Harrold, Senior Editor, dharrold@reedbusiness.com