Effects of chemical environment on softwood kraft pulp: exploring beyond conventional washing methods
Source abstract
Abstract
Abstract Brownstock washing, a critical process in cleansing kraft pulp, removes dissolved lignin residues from the pulp after it has passed through the cooking digester. It plays a significant role in kraft pulp mills by enhancing economic efficiency and environmental sustainability. Improved washing efficiency leads to better pulp quality and more effective recovery of cooking chemicals. Our study aimed to better understand the impact of different chemical compositions in washing liquors on washing performance. We tested a range of washing liquors, including neutral solutions (deionized water, 1M NaCl, 3M NaCl, 1M Na2SO4) and alkaline solutions (tap water, washing liquor composed of 0.35M NaOH and 1M Na2SO4, and white liquor with 50 g[OH]/l and 8.77 g[HS]/l). These liquors were evaluated for their efficacy in maximizing lignin extraction. Our findings suggest that salt solutions generally reduce washing efficiency. Deionized water and white liquor proved to be the most efficient washing agents, while high-concentration salts and those with high ionic strength negatively impacted washing efficiency. This suggests that brownstock washing may not be operating at its full potential.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Lignin and Wood Chemistry · Wood Treatment and Properties · Advanced Cellulose Research Studies
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Fiber and Polymer Technology, School of Chemistry, Biotechnology and Health , Royal Institute of Technology , Teknikringen 56-58, 100 44 , Stockholm , Sweden
Wallenberg Wood Science Centre, Department of Fiber and Polymer Technology, School of Chemistry, Biotechnology and Health , Royal Institute of Technology , Teknikringen 56-58, 100 44 , Stockholm , Sweden
Valmet AB , 851 94 , Sundsvall , Sweden
Funding
VINNOVA
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