1. A method for abnormal event detection (AED) for some process units of a delayed coking unit (DCU) comprising: (a) Comparing online measurements from the process units to a set of models for normal operation of the corresponding process units, (b) Determining if the current operation differs from expected normal operations so as to indicate the presence of an abnormal condition in a process unit, (c) Assisting the process operator to determine the underlying cause of an abnormal condition in the DCU, and (d) Performing corrective action to return the unit to normal operation.