(31g) Steam System Process Upset Review & Validation of Response

Steam systems in Ethylene Plant are relatively complex and involve a relatively large number of users distributed across different steam pressure level. It is difficult to breakdown the system when performing Hazard and Operability study (HAZOP) due to many parallel inputs and outputs. What If analysis relies on many assumptions with little insight on the system dynamic other then trends from previous upsets. A dynamic model of the steam and condensate system has been build with Aspen Dynamics to study the behavior of the system under process upsets. This paper describes the model configuration and its effectiveness in emulating previous upsets experienced in the Plant. The upsets cases cover boiler trips, compressor trips and power failure. Use of the model for developing and validating response to the above upset cases is also discussed.