Final Report ''Model-Based Approach to Soft-Sensing and Diagnosis for Control of a Continuous Digester''

Abstract

Project Objective: The goal of the work was to develop and demonstrate computing based modeling and control methodologies that will facilitate integrated operations on the continuous pulp digester. The technical work required to achieve these goals included development of efficient methods for softsensing using fundamental models, integration of fault monitoring and control algorithms, and the development of computationally feasible formulations of model predictive control for profile management in the digester. The developed operational methodology for digester grade transition control was benchmarked against an industrial design in cooperation with our collaborators at Weyerhaeuser and Westvaco. Background:The pulp and paper industry, a large and important sector of the CPI, is the most capital intensive among the sectors. While other components of the chemical industry have rapidly exploited model-based methods for improved operation, the PPI has lagged behind. Furthermore, as the US paper industry is moving from high volume single grade production to multi-grade continuous production, which offers the possibility for faster response to customer needs and production of higher margin specialty products, there arises the technical challenge of controlling the plant under the transient conditions which tend to propagate through the entire Final Report 6/1/03 DE-FC07-00ID13882