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The solubility of calcium carbonate in green liquor handling systems, TAPPI Journal October 2019

ABSTRACT: The formation of hard calcite (CaCO3) scale in green liquor handling systems is a persistent problem in many kraft pulp mills. CaCO3 precipitates when its concentration in the green liquor exceeds its solubility. While the solubility of CaCO3 in water is well known, it is not so in the highly alkaline green liquor environment. A systematic study was conducted to determine the solubility of CaCO3 in green liquor as a function of temperature, total titratable alkali (TTA), causticity, and sulfidity. The results show that the solubility increases with increased temperature, increased TTA, decreased causticity, and decreased sulfidity. The new solubility data was incorporated into OLI (a thermodynamic simulation program for aqueous salt systems) to generate a series of CaCO3 solubility curves for various green liquor conditions. The results help explain how calcite scale forms in green liquor handling systems.

To Canfor, Pulp is Much More than a Commodity, Paper360º September/October 2019

To Canfor, Pulp is Much More than a Commodity, Paper360º September/October 2019

Walter Schalka: RISI’s Four-time Latin American CEO of the Year, Paper360º September/October

Walter Schalka: RISI’s Four-time Latin American CEO of the Year, Paper360º September/October

TAPPI Journal Summaries, Paper360º September/October

TAPPI Journal Summaries, Paper360º September/October

UPM CEO Jussi Pesonen Named European CEO of the Year, Paper360º March/April 2019

UPM CEO Jussi Pesonen Named European CEO of the Year, Paper360º March/April 2019

Lignin value prior to pulping (LVPP): An advanced pulping c

Lignin value prior to pulping (LVPP): An advanced pulping concept, TAPPI JOURNAL October 2017

Degradation of 2,4-dichlorophenol by melamine amine cellulos

Degradation of 2,4-dichlorophenol by melamine amine cellulose- immobilized lacasses, TAPPI JOURNAL October 2017

Taking the Guesswork Out of Decarbonizing Pulp and Paper Mills, Paper360º September/October 2024

TAPPI Journal Summaries, Paper360º September/October 2024

Optimizing OCC refining with defloccing, TAPPI Journal April 2025

ABSTRACT: Subjecting pulp to a high shear zone immediately after refining results in more efficient refining. This phenomenon was originally observed to benefit softwood pulp refining. It was attributed to floc reduction based on floc measurements in mill refiners and the observation of reduced headbox plugging. Hence, this phenomenon has been termed “defloccing.” The present work shows this technology also benefits refining of North American old corrugated containers (OCC). The combined results of several mill trials with OCC defloccing demonstrate the interactions between OCC refining intensity, defloccing technology, and other state-of-the-art refining improvements. At the same refining intensity, defloccing OCC on 100% recycled machines increases OCC refining efficiency by 15%, with greater efficiency improvement on machines that use softwood as well as OCC. Furthermore, it is shown that the benefits of defloccing are additive to refining improvements made in the refining zone of a refiner plate. Most OCC refiner plate designs can therefore benefit from the addition of a defloccing feature.