Design, optimization and modelling of a chemical recovery system for wet spinning of cellulose in sodium carbonate solutionsShow others and affiliations
2020 (English)In: Cellulose, ISSN 0969-0239, E-ISSN 1572-882X, Vol. 27, p. 8681-8693Article in journal (Refereed) Published
Abstract [en]
The aim of this study is to present the design, optimization and modelling of a chemical recovery system for a novel CS2-free viscose-type process that entails dissolution of pre-treated dissolving pulp in a continuous-flow reactor in cold alkali and wet spinning of cellulose in sodium carbonate solutions. Technologies already known to other industries for the recovery and reuse of chemicals, such as causticizing, recalcination, recarbonization and freeze-separation, were used. Chemical equilibria simulations were performed with OLI Studio 9.5, with the purpose to select experimental conditions which avoid undesired precipitations in each unit operation. Synthetic solutions mimicking the spent coagulation liquor were used in the laboratorial experiments. The proposed chemical recovery system was shown to be technically feasible and reduce chemical make-ups to a minimum of 45 kg/ton of NaOH and 4 kg/ton of H2SO4. Small amounts of Zn are expected to precipitate during recarbonization of the coagulation liquor at 30 °C and causticizing at 98 °C. Thus, a filter for ZnO particles should be included in the design of the recarbonization unit and a continuous purge of lime mud and input of fresh lime make-up should be needed to keep burnt lime availability at an acceptable level. Overall, the results presented in this study portray a solution to reduce operating costs and the environmental impact of novel viscose-type processes with alkaline spin dopes and wet spinning of cellulose in sodium carbonate solutions. © 2020, The Author(s).
Place, publisher, year, edition, pages
Springer , 2020. Vol. 27, p. 8681-8693
Keywords [en]
Causticizing, Chemical recovery, Freeze-crystallization, Process modelling, Recarbonization, Regenerated cellulose, Textile fibre, Alkalinity, Calcium oxide, Carbonation, Cellulose, Coagulation, Environmental impact, II-VI semiconductors, Lime, Operating costs, Oxide minerals, Recovery, Sodium Carbonate, Sodium hydroxide, Structural design, Zinc oxide, Chemical equilibriums, Chemical recovery systems, Continuous flow reactors, Dissolving pulp, Experimental conditions, Recalcination, Synthetic solutions, ZnO particles, Molecular biology
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:ri:diva-47690DOI: 10.1007/s10570-020-03394-1Scopus ID: 2-s2.0-85089742374OAI: oai:DiVA.org:ri-47690DiVA, id: diva2:1463262
Note
Funding details: 720729; Funding text 1: Open access funding provided by RISE Research Institutes of Sweden. This research was conducted within the Project “NeoCel” that received funding from the Bio Based Industries Joint Undertaking within the European Union’s Horizon 2020 research and innovation program, under Grant Agreement No. 720729.
2020-09-012020-09-012023-05-25Bibliographically approved