An Industry Perspective of Cold Box NOx Safety Practices

Managing NOx safety considerations are a key issue for all ethylene producers. A task group has met intermittently to discuss safety issues associated with NOx compound accumulations in ethylene plant cold boxes over the past 20 years. The group has presented updates and provided tutorials on this subject to increase industry awareness.

This paper summarizes the most recent activity of the task group which is focused on proceedings from a 2019 group meeting. Since the task group last met in September 2012, the meeting was focused on understanding how industry NOx knowledge and operating experience has continued to evolve. Specifically, the paper summarizes NOx mitigation methods and implementation learnings, new areas of chemistry understanding and NOx risk analysis basis setting. In the end, this summary will further enhance industry NOx understanding and application.