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Journal articles
Recovery boiler sootblowers: History and technological advances 15-Jan-51
Recovery boiler sootblowers: History and technological advances, TAPPI JOURNAL January 2015
Journal articles
New challenges regarding nonprocess elements in the liquor and lime cycle, TAPPI JOURNAL July 2015
New challenges regarding nonprocess elements in the liquor and lime cycle, TAPPI JOURNAL July 2015
Journal articles
Upgrading aeration system performance in secondary basins treating pulp and paper wastewater: A review, TAPPI JOURNAL June 2015
Upgrading aeration system performance in secondary basins treating pulp and paper wastewater: A review, TAPPI JOURNAL June 2015
Journal articles
2015 TAPPI Centennial Celebration, TAPPI JOURNAL 2015 March - 15MAR100
2015 TAPPI Centennial CelebrationHonoring Our Past, Inspiring Our Future, TAPPI JOURNAL March 2015
Journal articles
Review of currently available technology for the conversion of woody biomass o value-added products 15MAR160
Review of currently available technology for the conversion of woody biomass to value-added products, TAPPI JOURNAL March 2015
Journal articles
Flippr° â?? an industrial research project in Austria, TAPPI JOURNAL 2015 March - 15MAR209
Flippr° â?? an industrial research project in Austria, TAPPI JOURNAL 2015 March - 15MAR209
Journal articles
Hardwood pulping kinetics of bulk and residual phases, TAPPI JOURNAL October 2015
Hardwood pulping kinetics of bulk and residual phases, TAPPI JOURNAL October 2015
Journal articles
Quantification of lignin-carbohydrate complexes in hardwood pulps, Part 2: Effects of bleaching chemicals, TAPPI JOURNAL October 2015
Quantification of lignin-carbohydrate complexes in hardwood pulps, Part 2: Effects of bleaching chemicals, TAPPI JOURNAL October 2015
Journal articles
Effects of D0-stage temperature, pH, and kappa factor on chl
Effects of D0-stage temperature, pH, and kappa factor on chlorine dioxide decomposition and D0-(EP)-D1 bleaching performance for eucalypt pulps, TAPPI JOURNAL April 2016
Journal articles
Assessing lignin content in Nordic hardwood and softwood species using models based on near-infrared (NIR) spectral data and partial least squares regression (PLSR), TAPPI Journal September 2025
ABSTRACT: Continuous kraft cooking digesters face challenges affecting product quality, making it valuable to improve control through advanced techniques like near-infrared (NIR) spectroscopy, model predictive control, and machine learning models. The primary goal of this study was to use NIR spectra to predict the amount of lignin in hardwood and softwood samples. This study investigated the correlation of NIR derivative spectra with the amounts of lignin relative to other constituents, namely cellulose, hemicellulose, and water, in wood chip samples of varying chip sizes and shapes from six Nordic wood species. It employed partial least squares regression (PLSR) on the NIR data to construct a model that predicted the lignin fraction and the relative fraction of acid-soluble lignin. When trained on a group of five wood species, the model achieved a satisfactory predictive ability, striking a balance between a wide range of lignin content and a consistent chemical environment. The accuracy increased further when the model was restricted only to spruce and pine, reflecting the benefits of a more homogenous dataset. Additionally, the optimal number of latent variables was identified as two, indicating that three distinct chemical components — cellulose, lignin and water — can be effectively differentiated using NIR.