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Journal articles
Magazine articles
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Impact of dissolved matter in the oxygen delignifcation stag

Impact of dissolved matter in the oxygen delignifcation stage, TAPPI JOURNAL May 2017

Journal articles
Magazine articles
Open Access
Accelerated aging of bio-oil from lignin conversion in subcr

Accelerated aging of bio-oil from lignin conversion in subcritical water, TAPPI JOURNAL March 2017

Journal articles
Magazine articles
Open Access
Using multistage models to evaluate how pulp washing after the first extraction stage impacts elemental chlorine-free bleach demand, TAPPI Journal November 2018

Using multistage models to evaluate how pulp washing after the first extraction stage impacts elemental chlorine-free bleach demand, TAPPI Journal November 2018

Journal articles
Magazine articles
Open Access
A model black liquor formulation for use in development and evaluation of membranes for concentrating  weak black liquor, TAPPI Journal February 2022

ABSTRACT: As part of a larger program to develop robust membranes for concentrating weak black liquor prior to the evaporation step, several commercially available membranes were tested for suitability in this application. Given the variation in kraft black liquor for various wood species, the mill-to-mill variations, and the challenges of obtaining fresh samples, the need became apparent for a synthetic reference black liquor that would allow any membrane developer to test a new prototype membrane and compare the results with others. We present a formulation for a model black liquor (MBL) similar to real kraft black liquor in the composition of the major species that can be formulated from readily available reagents. The MBL was tested with two commercial membranes and resulted in similar levels of lignin retention as the real black liquor. It also showed similar viscosity behavior to real black liquor as a function of solids content.

Journal articles
Magazine articles
Open Access
Recent advances in lignin-based polyurethanes, TAPPI JOURNAL

Recent advances in lignin-based polyurethanes, TAPPI JOURNAL April 2017

Journal articles
Magazine articles
Open Access
Fractional pulping of packaging board in high consistency drum pulping, TAPPI JOURNAL February 2017

Fractional pulping of packaging board in high consistency drum pulping, TAPPI JOURNAL February 2017

Journal articles
Magazine articles
Open Access
Editorial: Professional Networking in the Nonwovens and Technical Textiles Sector

Editorial: Professional Networking in the Nonwovens and Technical Textiles Sector, TAPPI Journal, May 2017

Journal articles
Magazine articles
Open Access
Editorial: Planning for 2017 PEERS Conference: Maximizing success through innovation, TAPPI JOURNAL January 2017

Editorial: Planning for 2017 PEERS Conference: Maximizing success through innovation, TAPPI JOURNAL January 2017

Journal articles
Magazine articles
Open Access
Technological evaluation of Pinus maximinoi wood for industrial use in kraft pulp production, TAPPI Journal August 2021

ABSTRACT: This study characterized Pinus maximinoi wood and evaluated its performance for pulp production. Samples of Pinus taeda wood were used as reference material. For both species, wood chips from 14-year-old trees were used for the technological characterization, pulping, bleaching process analysis, and pulp properties. A modified kraft pulping process was carried out targeting kappa number 28±5% on brownstock pulp. The bleaching sequence was applied for bleached pulp with final brightness of 87±1 % ISO. Refinability and resistance properties were measured in the bleached pulps. Compared to P. taeda wood, P. maximinoi showed slightly higher basic density (0.399 g/cm³) and higher holocellulose (64.5%), lignin (31.1%), and extractives content (4.5%), along with lower ash content (0.16%). P. maximinoi tracheids showed greater wall thickness (6.4 µm) when compared to P. taeda tracheids. For the same kappa number, P. maximinoi and P. taeda resulted in similar screened yield, with an advantage observed for P. maximinoi, which resulted in lower specific wood consumption (5.281 m³/o.d. metric ton), and lower black liquor solids (1.613 metric tons/o.d. metric ton). After oxygen delignification, P. maximinoi pulp showed higher efficiency on kappa reduction (67.2%) and similar bleaching chemical demand as P. taeda pulp. Compared to P. taeda pulps, the refined P. maximinoi pulps had similar results and the bulk property was 10% higher. Results showed that P. maximinoi is an interesting alternative raw material for softwood pulp production in Brazil.

Journal articles
Magazine articles
Open Access
Web lateral instability caused by nonuniform paper properties, TAPPI Journal January 2022

ABSTRACT: Lateral or cross-machine direction (CD) web movement in printing or converting can cause problems such as misregistration, wrinkles, breaks, and folder issues. The role of paper properties in this problem was studied by measuring lateral web positions on commercial printing presses and on a pilot-scale roll testing facility (RTF). The findings clearly showed that CD profiles of machine direction (MD) tension were a key factor in web stability. Uneven tension profiles cause the web to move towards the low-tension side. Although extremely nonuniform tension profiles are visible as bagginess, more often, tension profiles must be detected by precision devices such as the RTF. Once detected, the profiles may be analyzed to determine the cause of web offset and weaving problems.Causes of tension profiles can originate from nonuniform paper properties. For example, by means of case studies, we show that an uneven moisture profile entering the dryer section can lead to a nonuniform tension profile and lateral web movement. Time-varying changes in basis weight or stiffness may also lead to oscillations in the web’s lateral position. These problems were corrected by identifying the root cause and making appropriate changes. In addition, we developed a mathematical model of lateral stability that explains the underlying mechanisms and can be used to understand and correct causes of lateral web instability.