(56a) Upstream Tank Battery Pressure Management using PLC-based MPC

A PLC-based multivariable controller is being used to manage central tank battery pressures and minimize well-head backpressure, while honoring gravity-feed flow requirements and process constraints. The controller adapts to varying well line-ups and rate changes as well as downstream pressure swings, significant valve stiction and significant ambient-temperature swings. The controller was designed and implemented using Lin and Associates' Model-less Multivariable Controller, Deltum-XMC. The first controller was commissioned in less than three days with no need for a step-test or process modeling; operating benefits were immediately recognized. A second controller with the same design was installed on another tank battery with different operating constraints and commissioned before the end of the first week. The project team installed controllers on additional tank batteries.