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Magazine articles
Fine Doing Fine but Uncoated Looks Exposed, Solutions!, May 2005, Vol. 88(5) (124KB)
Fine Doing Fine but Uncoated Looks Exposed, Solutions!, May 2005, Vol. 88(5) (124KB)
Magazine articles
Optimization through storage, make down, and feed, Solutions!, May 2005, Vol. 88(5) (288KB)
Optimization through storage, make down, and feed, Solutions!, May 2005, Vol. 88(5) (288KB)
Magazine articles
Climate Commitments Create New Challenges, Solutions!, May 2005, Vol. 88(5) (522KB)
Climate Commitments Create New Challenges, Solutions!, May 2005, Vol. 88(5) (522KB)
Magazine articles
PIMA It: Collaboration and Integration Keys to success, Solutions!, November 2005, Vol. 88(11) (124 KB)
PIMA It: Collaboration and Integration Keys to success, Solutions!, November 2005, Vol. 88(11) (124 KB)
Magazine articles
Sweden Sees Restructuring Allied with New Investment, Solutions!, November 2005, Vol. 88(11) (252 KB)
Sweden Sees Restructuring Allied with New Investment, Solutions!, November 2005, Vol. 88(11) (252 KB)
Magazine articles
Tales from Process Controlâ??s Front Line, Solutions!, November 2005, Vol. 88(11) (164 KB)
Tales from Process Control’s Front Line, Solutions!, November 2005, Vol. 88(11) (164 KB)
Magazine articles
Wet End Chemistry: Doing More With Less, Solutions!, November 2005, Vol. 88(11) (300 KB)
Wet End Chemistry: Doing More With Less, Solutions!, November 2005, Vol. 88(11) (300 KB)
Journal articles
Magazine articles
Effects of different soda loss measurement techniques on brownstock quality, TAPPI Journal July 2024
ABSTRACT: The efficiency of the kraft recovery plant, bleaching process, and paper machine are affected when black liquor carryover from the brownstock washers is not controlled well. Measuring soda loss within a mill can vary from using conductivity, either in-situ or with a lab sample of black liquor filtrate squeezed from the last stage washer, to measuring absolute sodium content with a lab sodium specific ion probe or spectrophotometer. While measuring conductivity has value in tracking trends in black liquor losses, it is not an acceptable method in reporting losses in absolute units, typically in lb/ton of pulp. This is further complicated when trying to benchmark soda loss performance across a fleet of mills with multiple washer lines. Not only do the testing methods vary, but the amount of bound soda on high kappa pulps can be significant. This variability creates inconsistent results, and studies are needed to understand the effect of different testing methods on the pulp quality. In this study, soda loss is expressed as sodium sulfate (Na2SO4). Four different methods to measure soda content in pulp off commercial brownstock washers were studied: full digestion (FD), washing soaking overnight and washing (WSW), soaking in boiling water and stirring 10-min (SW-10), and squeeze-no wash (Sq). Total, washable, and bound sodium sulfate calculations were determined for each soda content measuring technique using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Results showed bound and washable sodium sulfate amounts significantly depend on which soda measurement technique was used. In addition, the soda results were correlated with the pulp kappa numbers. As the kappa number increases, bound soda increases, regardless of the soda measurement method used. Impacts of high sodium sulfate in brownstock are also discussed.
Journal articles
Magazine articles
Editorial: Special pulping and engineering issues of TAPPI Journal yield important recovery cycle research, TAPPI Journal June 2024
ABSTRACT: The June issue of TAPPI Journal, which is dominated by recovery cycle topics, is the last PEERS issue organized by Dr. Peter Hart, the fomer editor-in-chief who passed away this past May. Peter, who was heavily involved with TAPPI’s Pulp Manufacture Division and various pulping-related committees, also started working with conference technical program planning starting in 2005 with the Engineering, Pulping and Environmental (EPE) Conference, which was the precursor to the more recent Pulping, Engineering, Environmental, Recycling and Sustainability (PEERS) Conference. He was also involved with other conference planning, including that for the International Pulp Bleaching Conference. In addition, Peter was a yearly attendee of such conferences starting as far back as 1990.
Journal articles
Magazine articles
Comparing a linear transfer function-noise model and a neural network to model boiler bank fouling in a kraft recovery boiler, TAPPI Journal, July 2024
ABSTRACT: Boiler bank fouling reduces heat transfer efficiency in kraft recovery boilers. Here, we model the relationships between boiler parameters and boiler bank pressure drop, an indicator of fouling, based on recovery boiler operating data. We compared two models: an autoregressive integrated exogenous (ARIX) model and a feedforward neural network. The ARIX model better simulates boiler bank pressure drop compared to the neural network (R2 of 0.64 vs. 0.58). Based on the ARIX model, we identified six boiler parameters that significantly influence boiler bank fouling and their relative contributions. Finally, we demonstrate how the models can simulate boiler bank pressure drop given artificial perturbations in boiler parameters.