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Journal articles
Current Pulp Production in Japan and its Research and Techno
Current Pulp Production in Japan and its Research and Technological Topics, 1994 International Pan Pacific Conference Proceedings
Journal articles
On-Line Basis Weight Gauging and Control System for the Manu
On-Line Basis Weight Gauging and Control System for the Manufacture of Moist Towelettes, 1991 Nonwovens Conference Proceedings
Journal articles
Progressive Deformation at the Crack Tip in Paper During Mod
Progressive Deformation at the Crack Tip in Paper During Mode 1 Fracture (Part 1 Bond Paper), 1991 International Paper Physics Conference Proceedings
Journal articles
CTMP in Fine Papers: On-Machine Surface Treatments for Impro
CTMP in Fine Papers: On-Machine Surface Treatments for Improved Brightness Stability, 1991 Papermakers Conference Proceedings
Journal articles
Solid-State Structure Comparison Between Standard LLDPE and
Solid-State Structure Comparison Between Standard LLDPE and Enhanced Performance LLDPE, 1995 Polymers, Laminations & Coatings Conference Proceedings
Journal articles
Lignin Recovery from Kraft Black Liquor: Preliminary Process
Lignin Recovery from Kraft Black Liquor: Preliminary Process Design, 1990 Pulping Conference Proceedings
Journal articles
Pulping and Papermaking Properties of Managed Second-Growth
Pulping and Papermaking Properties of Managed Second-Growth Softwoods, 1995 Pulping Conference Proceedings
Journal articles
Tailoring Fiber Properties to Paper Manufacture: Recent Deve
Tailoring Fiber Properties to Paper Manufacture: Recent Developments, 1995 Pulping Conference Proceedings
Journal articles
Nonlinear modeling of batch digester discharge dynamics with rheology-driven hydraulic transport and drainability coupling, TAPPI Journal September 2026
ABSTRACT: Batch digester blowdown constitutes a strongly nonlinear transient transport process governed by the coupled evolution of pulp consistency, slurry density, hydraulic resistance, liquid inventory, and discharge line dynamics. A control-oriented nonlinear formulation is developed by coupling dry fiber and free liquor mass balances with phase volume reconstruction, consistency-dependent hydraulic resistance, channeling and drainability effects, and a power law head flow relationship derived within a lumped hydraulic inertance framework. A fixed-gain PI con troller obtained from local linearization is employed as the conventional benchmark, whereas an integral sliding mode controller (SMC) explicitly compensates the nonlinear time-varying hydraulic structure and bounded disturbances. Both strategies are evaluated under identical actuator constraints and sequential perturbations involving oppos ing head, hydraulic resistance, channeling, drainability, and dilution. Numerical results demonstrate lower root mean-square error, integral absolute error, and peak flow-tracking error for the SMC, with rapid recovery toward the prescribed sliding boundary layer and improved robustness to variations in the nonlinear flow exponent n. Cumulative electrical energy and batch-specific specific energy consumption remain comparatively similar, indicat ing that the principal SMC benefit is enhanced hydraulic regulation rather than substantial batch energy reduction. Specific energy consumption is an established metric for energetic assessment of slurry transport. Model-based hydraulic demand, electrical power, and sliding manifold surfaces further characterize the nonlinear operating domain. The resulting framework provides a computational proof-of-concept for modeling and control of transient batch digester discharge systems.
Journal articles
Optimization of optical coverage of board surfaces with assessment of light scattering and absorption using mineral as a coating component, TAPPI Journal June 2026
ABSTRACT: One of the primary functions of mineral inclusion into paper or paperboard is to improve the optical performance of the substrate. A coating may be applied to a sheet in order to cover a dark base, to improve the sheet opacity, to give the correct smoothness and gloss, or to give a suitable surface on which to print. The brightness of a pigment has long been used as a guide for pigment choice in paper and board. However, the measured paper brightness is a function of color and light absorption (K) of the coating and base and the light scattering (S) within the sheet resulting from interfaces with different refractive index. The optical performance can be quantified by measuring the S&K coefficients as described by the Kubelka-Munk model/theory in a filled or coated paper sheet. In coating, this is often assessed as a function of coat weight, and the corresponding physical sheet properties are assessed at the same time; for example, the correct gloss, smoothness, point-to-point uniformity, and printability. The optical performance in the sheet is often not directly related to the pigment brightness, but is largely a function of the particle packing within the sheet and coating layer. In the first and second main sections of this work, respectively, we show how S&K calculations from the Kubelka- Munk equations can be used in coated sheets to determine the optical performance and how this can be used as a predictive tool for the final sheet performance. This is presented for base sheets with different starting brightness. The third section of this work focuses on how mineral combinations in coatings can be used to improve the light scattering and consequently the optical performance of the board. We include theoretical considerations and then finally share a case study for improvement on the optical properties of recycled board.