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Hydrogen Peroxide Decomposition During Pressurized Peroxide Bleaching, 1996 Pulping Conference Proceedings
Hydrogen Peroxide Decomposition During Pressurized Peroxide Bleaching, 1996 Pulping Conference Proceedings
Advanced Control of a Dual Vessel Continuous Digester Running ISO -Thermal Cooking, 1998 Pulping Conference Proceedings
Advanced Control of a Dual Vessel Continuous Digester Running ISO -Thermal Cooking, 1998 Pulping Conference Proceedings
Particulate Emissions from Char Bed Burning, 2004 International Chemical Recovery Conference
Particulate Emissions from Char Bed Burning, 2004 International Chemical Recovery Conference
Use of Computer Modeling for Closed-Cycle Assessment and Design, 1996 International Pulp Bleaching Conference Proceedings
Use of Computer Modeling for Closed-Cycle Assessment and Design, 1996 International Pulp Bleaching Conference Proceedings
Mill Closure with Enhanced Peroxide Stages, 1997 Minimum Effluent Mills Symposium Proceedings
Mill Closure with Enhanced Peroxide Stages, 1997 Minimum Effluent Mills Symposium Proceedings
New Clathrate Hydrates for Second Generation Freeze Concentration Applicaiton in Paper Industry, 1997 Papermakers Conference Proceedings
New Clathrate Hydrates for Second Generation Freeze Concentration Applicaiton in Paper Industry, 1997 Papermakers Conference Proceedings
Mechanism and Kinetics Studies of Oxidative Ammonolysis of Technical Lignins, 2000 Pulping / Process & Product Quality Conference Proceedings
Mechanism and Kinetics Studies of Oxidative Ammonolysis of Technical Lignins, 2000 Pulping / Process & Product Quality Conference Proceedings
Books
Kraft Recovery Boilers, Third Edition Now Available From TAPPI Press
The much-anticipated update of bestseller provides rapid access to recovery boiler technology
Journal articles
Optimization of energy efficiency and condensate production in evaporation plants for a modern softwood pulp mill, TAPPI Journal April 2026
ABSTRACT: To meet the need to further improve thermal efficiency and environmental performance of kraft pulp mills, new systems and techniques have been developed within the evaporation plant. This paper describes these novel approaches and how they were implemented in a project completed in 2018 for a new evaporator and condensate treatment system supplied by Valmet at the SCA Östrand market pulp mill in Sweden. This project was part of a stepwise upgrade of the complete mill to increase the production capacity of the mill from 430,000 to 900,000 air-dried metric tons/year (ADt/y). As part of this upgrade, the mill had the objectives to increase the energy efficiency of the pulp mill and to minimize the air emissions as much as possible, the effluent volume, and the water usage in the mill. The mill also wanted to have the disposal of the biosludge in the black liquor, and the production of tall oil from black liquor soap, liquid methanol, and turpentine. This required that the new evaporation and condensate treatment system be very closely integrated into the other process departments of the mill, including integration of the hot weak black liquor flash vapor from the digester directly into the evaporator train and the production of multiple streams of clean evaporation plant condensate at the correct temperature for the bleach plant. Heat and mass balance calculation values, which were found to do very well in predicting the effect on actual mill operation, are also presented in this paper.
Journal articles
Towards closed water systems in chemical pulp mills: Evaporation of acidic filtrate from ECF bleaching with high chloride content, TAPPI Journal January 2026
ABSTRACT: In modern bioproducts mills utilizing elemental chlorine-free (ECF) bleaching, the bleaching process is the primary effluent source. The pulp bleaching typically generates 10 m³/a.d. metric ton of acidic filtrate. Despite extensive studies on recycling methods, the acidic filtrate is still typically directed to wastewater treatment plants due to the challenges created by its volume and chloride content. Recently, the volume of acidic filtrate has significantly decreased to 5 m³/a.d. metric ton, reducing the capacity required for the recycling process closer to a feasible level. In this study, we investigated recycling of acidic filtrate by evaporation from the D0 stage of a D0-Eop-D1 bleaching sequence. In the mill, hydrochloric acid (HCl) was used for pH control instead of sulfuric acid (H2SO4) due to better control of precipitation. This arrangement substantially changes the composition of the acidic filtrate, increasing the chloride (Cl-) and decreasing the sulfate (SO4 2-) ionic content. For the above reasons, it is necessary to study the effect of evaporation on the quality of the resulting condensate and concentrate. The results provide new information on how to close water loops in a modern bioproducts mill with higher Cl- content as one option. The results show that the evaporation of the high-chlorine D0 filtrate produces a pure condensate with methanol as the main component. Only small amounts of Cl- were observed in the condensate. The majority of chlorine (Cl) compounds remains as dissolved compounds in the evaporated concentrate when the dry solids content of the concentrate is ~10%. The Cl compounds in the concentrate can be converted to sodium chloride (NaCl) by incineration.