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SETPOINT: Let’s Finally Talk About Bruno, Paper360º March/April 2022

SETPOINT: Let’s Finally Talk About Bruno, Paper360º March/April 2022

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.

Trends in China’s Pulp, Paper, and Forestry Industry, Paper360º March/April 2024

NA’s First Smelt Spout Robot Elevates Safety, Productivity, Paper360º March/April 2024

Meeting the Future Through Knowledge Sharing and Connection, Paper360º March/April 2023

TAPPI Journal Summaries, Paper360º September/October 2023

Editoral: Investing in the future: Writing and peer-reviewing for TAPPI Journal, TAPPI Journal July 2024

ABSTRACT: Those who actively participate in TAPPI realize how much there is to gain from the networking, educational resources, career development, and other opportunities that come with this involvement. One important opportunity is the ability to share your work and expertise with others in your field, and an excellent way to do this is by taking part in the TAPPI Journal peer-review process, either as an author or a reviewer or both.

Coarse Filtration is the ´First Line of Defense’, Paper360º January/February 2021

Coarse Filtration is the ´First Line of Defense’, Paper360º January/February 2021

Editorial: 2018 TAPPI Journal features diverse content, TAPPI Journal November 2018

Editorial: 2018 TAPPI Journal features diverse content, TAPPI Journal November 2018

Three-dimensional pore structure visualization and character

Three-dimensional pore structure visualization and characterization of paper using X-ray computed tomography, TAPPI JOURNAL September 2017