Process Control in Ethylene Plants: A Historical Perspective

Process control has been the cornerstone of automation technology in ethylene plants for the past several decades. Stiff global competition combined with intermittent periods of uncertain market growth has forced the industry to re-evaluate business models and to continuously search for innovative ways to achieve operational excellence and optimize production efficiency. Over the years, the development and convergence of many different niche technologies has significantly contributed to enhancing process controls’ role as the primary enabler for improving ethylene plant performance. To commemorate the twenty fifth anniversary of the Ethylene Producers Conference, this paper traces the evolution of process control over the past three decades and examines the various technological developments as well as human factors that have collectively shaped what process control is today. The paper reviews the evolution and commoditization of the Distributed Control System (DCS) and its eventual transformation into a graphical, highly interactive integration platform that provides process control functionality as well as real-time data connectivity between the plant floor and the enterprise. In addition, the paper describes the revised role of the ethylene plant operator and the process control engineer, the emergence of analyzer technologies and smart sensors that have significantly improved the ability to monitor and control difficult processes, and the proliferation of advanced process control and real-time optimization applications in ethylene plants.