(71d) Incidents: Berre Ethylene Plant and Others

This tutorial will review some of the background chemistry, the analytical methods, the findings of various ethylene producers and the techniques used by various ethylene producers and designers to deal with the hazards of NOx accumulations in cryogenic recovery systems. There have been a number of events where containment was lost due to the detonation of complex NOx-hydrocarbon gums and/or NOx-salts in cryogenic recovery systems. These events have occurred not only in the ethylene industry but other chemical units. Actual case histories will be described, and learnings from those cases discussed. This tutorial has been developed to provide information for engineers and plant operating personnel who are relatively new to the ethylene industry and for those who are un-familiar with the hazards of NOx accumulations in the cryogenic sections of ethylene recovery units.