Application of abnormal event detection technology to hydrocracking units

Abstract

The present invention is a method for detecting an abnormal event for process units of a hydrocracking unit. The method compares the operation of the process units to a model developed by principle components analysis of normal operation for these units. If the difference between the operation of a process unit and the normal operation indicates an abnormal condition, then the cause of the abnormal condition is determined and corrected.

Description

[0001] This application claims the benefit of U.S. Provisional application 60 / 609,161 filed Sep. 10, 2004.BACKGROUND OF THE INVENTION [0002] The Hydro Desulfurization and Cracking unit (HDC) is an important process unit within a petroleum refinery. The HDC converts heavy aromatic compounds, typically a combination of cycle oil and coker naptha feeds, into lighter products which can be blended into gasoline and jet fuels. The primary processing equipment for an HDC are multiple sequential fixed bed reactors (for hydrocracking and hydrotreating) and product fractionation columns. Due to the fast dynamics of the process, the highly exothermic kinetics of the reactions, and the large degree of interaction between the process equipment of the HDC, abnormal process operations can arise which cause the HDC to deviate from the normal operating state. Abnormal operations of the HDC can have significant safety and economic consequences. These situations can cause catalyst or equipment damage,...

AI Technical Summary

Benefits of technology

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Problems solved by technology

Due to the fast dynamics of the process, the highly exothermic kinetics of the reactions, and the large degree of interaction between the process equipment of the HDC, abnormal process operations can arise which cause the HDC to deviate from the normal operating state.

Abnormal operations of the HDC can have significant safety and economic consequences.

These situations can cause catalyst or equipment damage, lost production, environmental emissions, injuries or fatalities.

This notification technology is challenged to provide timely alarms while sustaining an acceptable rate of false notifications when the key measurements are correlated for complicated processes such as an HDC.

Due to the complexity and the fast dynamics of an HDC, this type of notification is often delivered too late to enable the console operator to have sufficient time to identify and take preventive action to mitigate the problem.

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