[EngDaniel]

I am currently working on an emissions abatement project that will  involve extracting vapor streams of Volatile Organic Compounds from various tanks and sending them to a Regenerative Thermal Oxidizer (RTO) for incineration before discharge into the atmosphere. The tanks/vessels will be inerted with nitrogen and the excess waste vapor fumes will vent into the pipe headers and sucked to RTO by fans.
 
My concept design incorporates the use of  standard Nitrogen Padding & Depadding Valves, Flame/Detonation Arresters, Oxygen Analyzers / LEL Detectors, Pressure-Vacuum Reliefs, Explosion Reliefs etc. I would welcome any advice on anything else I should consider in the project.
 
How best can I predict the maximum volumetric flows and the Nitrogen and VOC components concentrations on the main header prior to the RTO.