Expert System for Anaerobic‐Digestion‐Process Operation

The anaerobic digestion process is sometimes subject to process upset and has earned the reputation of being difficult to operate. Knowledge and its processing are limiting factors in achieving effective operation. These limitations can be addressed by development of knowledge‐based, or expert, decision support systems. This study was conducted to examine the design and development of a rule‐based expert system for operation of the anaerobic digestion process. The expert system contains knowledge necessary to diagnose and specify control actions properly for correcting hydraulic, organic, toxic, and ammonia upsets in anaerobic digestion. Examples are given of the expert system's behavior in control of hydraulic and ammonia upsets, showing the manner in which inferences are made and how corrective actions are taken. Examination of the expert system for the overall process showed the potential for use of this kind of tool as an operational aid but also indicated that improved procedures for validation of the knowledge base are needed.