Search

Image classification of the furnace bed height in recovery boilers, TAPPI Journal July 2026

ABSTRACT: The goal of this study is to develop an approach for classifying char bed height in a recovery boiler during operation. The resulting classified images form a dataset that can be used by the mill to support operational improvements. The study integrates data from the digester, evaporation plant, recovery boiler, and recausticizing plant, along with the classified image data. A convolutional neural network (CNN) was trained on bed camera images that were manually annotated to classify furnace bed height. The model was then used to generate a binary bedheight parameter over a 16-month period, and an extreme gradient boosting (XGBoost) model was applied to identify relationships with operating parameters across the recovery cycle. The outcomes of this research may offer deeper insights into the processes underlying bed dynamics. Ultimately, the developed system may serve as a tool for optimizing bed conditions and supporting stable combustion.

Estimating dose and interaction of X-rays with cellulose-based fibrous materials using micro-computed tomography, TAPPI Journal March 2026

ABSTRACT: Micro-computed tomography (ìCT) has a reputation as a nondestructive analysis method. Unfortunately, this leads to the common misconception that radiation damage of the sample does not play a role. With the increased use of ìCT in laboratory-based machines, more and more cellulose-based materials are studied. In this paper, we show with three examples that radiation damage is important in dry and wet paper and in viscose fibers. In an attempt to quantify radiation damage, we came up with a workflow that enables researchers to predict the X-ray dose within a laboratory-based ìCT machine. This gives researchers the possibility to quantitatively judge the influence of radiation damage on each measured sample. While one cannot extend the measured doses from one machine to another, one can still apply the work flow presented in this study to any ìCT setup. In this way, it is possible to minimize radiation damage by choosing the best parameters in a ìCT for obtaining perfect data with no or little radiation damage.

Leaching of Chloride and Potassium from Electrostatic Precipitator Catch, 1998 International Chemical Recovery Conference Proceedings

Leaching of Chloride and Potassium from Electrostatic Precipitator Catch, 1998 International Chemical Recovery Conference Proceedings

Impulse Drying: Status of the Pilot-Scale Research Program, 1998 Engineering Conference Proceedings

Impulse Drying: Status of the Pilot-Scale Research Program, 1998 Engineering Conference Proceedings

How Mechatronic Engineering Led to 'Intelligent' Paper Roll

How Mechatronic Engineering Led to 'Intelligent' Paper Roll Clamps, 1993 Finishing and Converting Conference Proceedings

Pulp and Paper Roofing - Considerations and Design, 1992 Eng

Pulp and Paper Roofing - Considerations and Design, 1992 Engineering Conference Proceedings

Control of Ergonomic Hazards by Workplace Design, 1992 Engin

Control of Ergonomic Hazards by Workplace Design, 1992 Engineering Conference Proceedings

In case you missed it in TAPPI’s electronic newsletter, Tissue360º Fall/Winter 2023

Achieve Superior Performance with TT Headbox, Tissue360º Fall/Winter 2023

Achieve Superior Performance with TT Headbox, Tissue360º Fal

Mechanistic aspects of nanocellulose•cationic starch•colloidal silica systems for papermaking, TAPPI Journal February 2023

ABSTRACT: Optimization of a chemical additive program for a paper machine can require attention to both colloidal charges and kinetic effects. This work considered an additive program with two negatively charged substances (nanofibrillated cellulose [NFC] and colloidal silica) and two positively charged items (cationic starch and cationic acrylamide copolymer retention aid). Results were shown to depend on charge interactions; however, that clearly was not the whole story. Some findings related to cationic demand, dewatering, fine-particle retention, and flocculation among fibers were best explained in terms of at least partly irreversible complexation interactions between the charged entities. Adjustments in ratios between oppositely charged additives, their sequences of addition, and effects of hydrodynamic shear levels all affected the results. In general, the most promising results were obtained at a cationic starch level of 0.25% to 0.5% based on sheet solids in systems where the cationic starch was used as a pretreatment for NFC.