Reliability Monitoring for Advanced Process Control Implementations

In the modern refinery (or chemical plant or paper mill or similar facility), Advanced/Multivariate Process Control (APC) is becoming a more frequent piece of the puzzle in economic optimization of operation.  Many vendors are implementing such systems, tune them up, and leave the facility.  After several months, if not sooner, operators sometimes revert to old operational habits disable the advanced controls.  Sometimes an operational incident occurs and APC is unfairly blamed as the cause; thus also causing disabling of the controls.  Operation becomes more single loop control, thus losing the economic benefits of APC implementations.  Area engineers will get tied up and not monitor usage and eventually no one even remembers the advanced controls.  APC implementations can become unreliable simply because of human factors and not technical factors.  Also, underlying regulatory controls can lose tuning due to equipment change or other factors, thus harming APC effectiveness. 

There are numerous presentations on APC and the benefits of its implementation.  This presentation is instead focused on one approach to helping keep APC in use and operating; remote usage and performance monitoring.  Usage monitoring indicates what percentage of operating time the APC controls are working, both at the master level and at the individual handle level.  Performance monitoring goes further, by looking at constraints and determining which of these may be tying down enhanced economic performance.  When an APC vendor works with the facility, both can work together to examine reports, see where potential enhancements lie, and take action.  The vendor/client model helps ensure that periodic reviews of process conditions are made and lends outside expertise and experience to the facility operations.  When coupled with appropriate monitoring reports, serious economic benefit can be realized.  In addition, poor APC performance can frequently indicate an underlying serious condition.

The focus on this presentation is on what information to glean from the APC and regulatory controls and how to handle this information to help improve operation.