Mayo, S. M.

Oklahoma State University, Stillwater, Oklahoma

Stephen M. Mayo has 38 yr of industry experience, and his research is focused on getting the most out of advanced process control. His career has included process engineering and management roles around the world in several different countries in ethylene, refining, LNG, and oil and gas production. Mr. Mayo earned an MBA degree from Oklahoma State University, where he is a chemical engineering doctoral candidate. He is also a registered professional engineer in Oklahoma.

APC maintenance scheduling—Part 1

Mayo, S. M., Rhinehart, R. R., Madihally, S. V., Oklahoma State University

Advanced process control (APC) projects are supervisory programs that are often thought of as a layer of control above the base regulatory control for a process. The benefits of APC include increased throughput, reduced variation, constraint avoidance, etc., and can be combined to represent a daily economic-equivalent benefit for the application—the same anticipated benefit that led to the justification of the APC installation. Several articles report that after 18 mos–24 mos, more than half of APC installations are performing at either pre-installation levels or have been removed.1,2,3 Although diverse reasons exist for the performance shortfall, a primary reason is that the process characteristics drift from those that generated the controller model.