Operators may be able to spot faults in plant operations far faster thanks to a centroid analysis tool developed by researchers at the University of Texas at Austin. The tool has dramatically outperformed other techniques and may provide a potent way to anticipate and address potential plant upsets.
Michael Baldea, an assistant professor in the school’s chemical engineering department, and graduate student Ray C. Wang presented impressive results of tests of the tool at the last meeting of the Center for Operator Performance (COP), Dayton, Ohio. The COP (www.operatorperformance.org) funded the development with the aim of creating a tool to help operators identify problems before they occur.
The tool beat by more than 90% the average detection time in the Tennessee Eastman Challenge Process, which is a realistic simulation of a chemical process that long has served as a way to evaluate control strategies for improving operations, they reported. The centroid approach detected six of the twenty faults considered in less than 30 minutes each. In addition, it picked up three hard-to-detect faults that were missed altogether or spotted too late by 12 other techniques whose results with the Tennessee Eastman Challenge Process appear in the literature.
The technique already has successfully detected impending surge in a large, multistage compressor; analysis of past surges identified an event signature hours before the onset of surge. The tool now is being tested on distillation tower flooding, fired heater (furnace) operation and flaring, say the researchers. These tests should be completed before the COP’s November meeting.
If these tests are successful, the next step would be to develop interfaces for real-time application in control systems, says the COP. This would involve active participation by the three automation vendors that are members of the center — ABB, Emerson Process Management and Yokogawa; Emerson already is engaged in the project.
“Being able to detect and visualize faults before they occur is very important. The methods being worked on by the COP are very promising. We look forward to testing these techniques on a wide range of applications,” comments Mark Nixon of Emerson.
A tool will undergo field-testing within a year, notes the COP.
The group expects to make the tool available first to its operating company members. Its automation vendor members then would offer the tool to the chemical industry in general.
