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Journal articles
Effects of localized environment on eucalyptus clone chemica
Effects of localized environment on eucalyptus clone chemical composition, TAPPI JOURNAL September 2016
Journal articles
Magazine articles
In-process detection of fiber cutting in low consistency ref
In-process detection of fiber cutting in low consistency refining based on measurement of forces on refiner bars, TAPPI JOURNAL April 2017
Journal articles
Magazine articles
Use of vent stack temperature as a feedforward variable for dissolver total titratable alkali (TTA) control, TAPPI JOURNAL May 2018
Use of vent stack temperature as a feedforward variable for dissolver total titratable alkali (TTA) control, TAPPI JOURNAL May 2018
Journal articles
Magazine articles
Understanding the pulping and bleaching performances of eucalyptus woods affected by physiological disturbance, TAPPI Journal November 2018
Understanding the pulping and bleaching performances of eucalyptus woods affected by physiological disturbance, TAPPI Journal November 2018
Journal articles
Estimation of the S/G Ratios of the Lignins in Three Widely
Estimation of the S/G Ratios of the Lignins in Three Widely used North American Hardwoods, TAPPI JOURNAL July 2016
Journal articles
Corrosion Mnitoring and Root Cause Identification in High So
Corrosion Mnitoring and Root Cause Identification in High Solids Concentrators, TAPPI JOURNAL July 2016
Journal articles
Evaluation of Near-Drum Thinning Data in Recovery Boiler Gen
Evaluation of Near-Drum Thinning Data in Recovery Boiler Generating Bank Tubes, TAPPI JOURNAL July 2016
Journal articles
Magazine articles
Functionalization of wood/plant-based natural celluslose fibers with nanomaterials: a review, TAPPI JOURNAL February 2018
Functionalization of wood/plant-based natural celluslose fibers with nanomaterials: a review, TAPPI JOURNAL February 2018
Journal articles
Magazine articles
Print quality of flexographic printed paperboard related to coating composition and structure, TAPPI Journal January 2018
Print quality of flexographic printed paperboard related to coating composition and structure, TAPPI Journal January 2018
Journal articles
Magazine articles
Control of continuous digester kappa number using generalized model predictive control, TAPPI Journal September 2024
ABSTRACT: Kappa number variability at the digester impacts pulp yield, physical strength properties, and lignin content for downstream delignification processing. Regulation of the digester kappa number is therefore of great importance to the pulp and paper industry. In this work, an industrial application of model-based predictive control (MPC), based on generalized prediction control, was developed for kappa number feedback control and applied to a dual vessel continuous digester located in Western Canada. The problem was complicated by the need to apply heat at multiple locations in the cook. In this study, the problem was reduced from a multiple to a single input system by identifying three potential single variable permutations for temperature adjustment. In the end, a coordinated approach to the heaters was adopted. The process was perturbed and modeled as a simple first order plus dead time model and implemented in generalized predictive control (GPC). The GPC was then configured to be equivalent to Dahlin’s controller, which reduced tuning parameterization to a single closed loop time constant. The controller was then tuned based on robustness towards a worst-case dead time mismatch of 50%. The control held the mean value of the kappa number close to the setpoint, and a 40% reduction in the kappa number’s standard deviation was achieved. Different kappa number trials were run, and the average fiberline yield for each period was evaluated. Trial results suggested yield gains of 0.3%•0.5% were possible for each 1 kappa number target increase.