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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
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.
Journal articles
Qualification of Welding Procedures for Duplex Stainless Ste
Qualification of Welding Procedures for Duplex Stainless Steels, 1999 Engineering Conference Proceedings
Journal articles
TRS inventories and air dispersion modeling for odor reduction at a kraft mill with an activated sludge treatment plant, TAPPI JOURNAL, April 2002 (281KB)
TRS inventories and air dispersion modeling for odor reduction at a kraft mill with an activated sludge treatment plant, SOLUTIONS! & TAPPI JOURNAL, April 2002 (281KB)
Journal articles
Catalysis and activation of oxygen and peroxide delignification of chemical pulps: A review, TAPPI JOURNAL, April 2002 (38KB)
Catalysis and activation of oxygen and peroxide delignification of chemical pulps: A review, SOLUTIONS! & TAPPI JOURNAL, April 2002 (38KB)
Journal articles
Oxygen delignification as a pretreatment for acetosolv pulps bleaching, TAPPI JOURNAL, April 2002, Vol. 1(2) (221KB)
Oxygen delignification as a pretreatment for acetosolv pulps bleaching, TAPPI JOURNAL, April 2002, Vol. 1(2) (221KB)
Magazine articles
Treatment efficiency of eucalypt kraft pulp bleaching effluents: influence of dissolved organic matter, SOLUTIONS! & TAPPI JOURNAL, April 2002 (128KB)
Treatment efficiency of eucalypt kraft pulp bleaching effluents: influence of dissolved organic matter, SOLUTIONS! & TAPPI JOURNAL, April 2002 (128KB)
Magazine articles
Barbara Dalpke: insights from a recent graduate, TAPPI JOURN
Barbara Dalpke: insights from a recent graduate, TAPPI JOURNAL, August 2002, Vol. 1(6) (144KB)
Journal articles
Measurement of kappa number variability on the fiber level, Solutions! & TAPPI JOURNAL, December 2002, Vol. 1(10) (147KB)
Measurement of kappa number variability on the fiber level, Solutions! & TAPPI JOURNAL, December 2002, Vol. 1(10) (147KB)
Journal articles
Using near-infrared multivariate image regression to predict pulp properties, Solutions! & TAPPI JOURNAL, May 2004, Vol. 3(5) (271KB)
Using near-infrared multivariate image regression to predict pulp properties, Solutions! & TAPPI JOURNAL, May 2004, Vol. 3(5) (271KB)