Document Type

Technical Report

Publication Date



Water quality control, water quality modeling, water quality monitoring, water quality standards


A diagnostic expert system for an activated sludge wastewater treatment plant has been designed to link with a relational database management system for obtaining operational parameter values that are used by the program to diagnose operational problems that may occur in the process. The problems that are dealt with by the system are bulking sludge, floating sludge, defloculation, ashing, solids washout, foaming problems, high soluble effluent BOD and problems in the aeration system. The link between the expert system and the database is accomplished via programming that is initiated by the expert system program. The operator of the system is not required to perform any action in order for the appropriate retrievals of operational parameter values to occur. The system is designed such that parameter values are retrieved from the database if such a database exists and contains appropriate values and, if no such database exists or if the appropriate values are not present, the operator is queried for the parameter values. Since many wastewater treatment plants maintain database management systems for operational parameter values, such an expert system has advantages over stand alone systems. However, an override of the database query is possible, making the system useful for experimental queries and for training.

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