Fault Tolerance Applies to a Black Liquor Recovery Boiler, 1996 Process Control, Electrical & Info. Conference Proceedings

The Weyerhaeuser Flint River Plant in Oglethorpe , Georgia recently undertook a project to improve the operation and safety of its black liquor recovery boiler. Included in this major project was a fault-tolerant control system to safely control the burners and to execute rapid drain logic for the 8 burner boiler. Of importance was the objective to meet modem standards for burner management and control. This paper presents an in-depth view of the planning, testing, installation, and start-up of this modem fault tolerant control system. The unique manner in which this project was developed and successfully completed as well as the theory of fault-tolerant operation is presented. Because of the emphasis on reliability and availability to meet or exceed regulatory requirements for safety systems, this paper provides a point of reference for those in the pulp and paper industry who may be involved in future critical equipment control projects.