(4c) Troubleshooting Process Control Problems to Improve Performance of Ethylene and Other Process Plants

This paper will address common, yet often hidden, process control problems that can adversely affect the overall performance of an ethylene plant or other hydrocarbon processing facility. These problems can usually be corrected without complicated software or highly specialized process control expertise. A checklist of typical control system problems, with guidelines explaining how process engineers can identify them, will be presented. Examples and suggestions to assist process and control engineers with avoiding and/or correcting these problems will also be addressed. Many of these problems exist from initial plant startup, never get corrected, and become part of the "that never worked" lore of the plant. These base level process control problems can also limit the ability of an advanced control system to achieve its full potential benefit. In fact, some of the benefit that is often attributed to advanced control technology is actually the result of correcting these problems during the implementation of an advanced control project.