Some Lessons Learned using Expert Systems for Process Control

An expert system is used to monitor an industrial process, looking for problems. When a problem occurs, the process operator is alerted and is told the problem and its probable cause. Experience with two processes, an adipic acid reactor and a heat exchanger, has led to practical results and to some lessons for using expert systems for process control. The lessons form the bulk of this paper, and deal with limits to expert systems, how and where an expert system fits in, knowledge-base engineering, and software engineering for expert systems.