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The Future of Water for the Pulp and Paper Industry, Paper360º July/August 2022

The Paper360° 2022 TOP 50 POWER LIST, Paper360º July/August 2022

Efficiency is Key for High Capacities, Paper360º March/April 2022

Efficiency is Key for High Capacities, Paper360º March/April 2022

Web instability in the open draw and the impact on paper machine efficiency, TAPPI Journal May 2022

ABSTRACT: Paper is most likely to break in the first open draw on a paper machine where it is unsupported, wettest, and weakest. Tension is applied to peel the web from the roll surface, as well as minimize web flutter in the open draw. The average tension is well below the breaking point and is often set by adjusting the speed difference between the press and the next machine element by visually observing the behavior of the web. However, machine direction variations caused by instabilities in the paper machine can cause tension swings that exceed the strength of the web. Measurement of the web’s release point from press rolls on pilot and commercial paper machines was used to identify the cause of tension instabilities. Variations in the speed of the paper machine drives and the work of adhesion from the press roll surface were identified as key factors. Fluctuations of paper moisture, which affects the elastic modulus and strength of the web, appear to be less important.

Pilot scale black liquor concentration using pressure driven membrane separation, TAPPI Journal April 2023

ABSTRACT: Black liquor concentration using pressure driven membrane separation has long been proposed as a means of achieving energy savings and breaking production bottlenecks. To date, limitations in membrane performance and stability under black liquor process conditions have prevented those promises from being realized out-side of tightly controlled laboratory settings. In this work, we describe the first successful pilot scale field deployments of a membrane system for black liquor concentration. Using a purpose-built system and commercial sized, spiral wound graphene oxide membrane elements, we have logged nearly 6000 h of runtime across deployments to multiple mill sites. We demonstrate concentration of black liquor from 14% to >20% total solids, while generating permeate water comparable in quality to that of evaporator condensate and an 81% reduction in energy consumption relative to evaporation. At a commercial scale, these results translate to $2 M/year in net energy savings for a typical mill, as well as an opportunity to support production increases or mill expansions. These results represent a significant leap forward in the ability of membrane systems to deliver substantial value via black liquor concentration.

Evaluation of soap recovery efficiency from black liquor — analytical tools, TAPPI Journal April 2023

ABSTRACT: Soap skimmings (“soap”) are typically recovered from black liquor in kraft mills that process a high percentage of softwood. In many mills, the recovery of soap is inefficient, negatively impacting performance of evaporators and recovery boilers and resulting in loss of potential revenue. A thorough evaluation of soap recovery performance in a kraft mill requires measurement of soap content in black liquor at various sampling locations, especially around the soap skimmer.The standard laboratory method for evaluating soap content in black liquor is a complex, multi-step process that relies on solvent extraction and titration; most mills send these samples to an outside laboratory for this analysis. In this study, 100 black liquor samples, with a wide range of soap concentrations, were tested by the standard solvent extraction method. After additional dilution, each sample was also tested for surface tension with a bubble pressure tensiometer. The results were found to correlate very closely with the solvent extraction tests results. This alternate method, using surface tension measurements of diluted black liquor samples, produces rapid results and can be easily implemented in most kraft mills, which would facilitate much more frequent in-house evaluations of soap recovery performance.

Maximizing Process Efficiency with Advanced Vacuum Systems, Paper360º September/October 2025

Corrosion-resistant fiberglass-reinforced plastic composites for chlorine dioxide environments - third report, TAPPI JOURNAL, January 1996, Vol. 79(1)

Corrosion-resistant fiberglass-reinforced plastic composites for chlorine dioxide environments - third report, TAPPI JOURNAL, January 1996, Vol. 79(1)

Fraser focuses on the future, TAPPI JOURNAL, June 1996, Vol. 79(6)

Fraser focuses on the future, TAPPI JOURNAL, June 1996, Vol. 79(6)

Panel discusses future papermaking technology, TAPPI JOURNAL, June 1996, Vol. 79(6)

Panel discusses future papermaking technology, TAPPI JOURNAL, June 1996, Vol. 79(6)