AWWA CSC92055

This paper discusses the new distributed computer control system component of the Harrington Water Treatment Facility in Nashville, Tennessee facility expansion. After describing the treatment train and the existing control system, the authors discuss how construction and installation of the new automation system was completed in phases to allow the plant to operate without interruption. The new distributed control system ensures reliable treatment plant operation and effluent quality through computer-aided operation. Other topics covered include the use of process control data for chemical usage trends, the input of laboratory data and the gathering of process control data for operational reports, and the compilation of process control data for use in future operation/treatment trends. Tables describe software characteristics, the alarm display for various problems, graphic display screens, and reports that are generated by the software.