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and demonstrated the potential advantages of using papermaking wastes as building materials (e.g., toughness enhancement and wood texture). Some experimental data (e.g., 6% AE, 20% waste addition) can also be used as a reference for the actual transformation of wastes in papermaking. However, the experimental findings have limitations in terms of generalization because the compositions of papermaking wastes from different sources vary considerably. The conclusions of this study are as follows: (1) According to the experimental results, the compressive strength showed a huge span of 14.5~73.7 MPa after curing for 28 days. When the BFS was partially substituted by the same proportion of wastes, the compressive strength decreased sequentially from the lime mud, paper sludge, bottom ash, and wood chips. The effect of the mixture of the lime mud and paper sludge on the compressive strength showed that for every 5% reduction in the proportion of lime mud, the strength decreased by nearly 2.5 MPa. (2) From the stress-time curves, neither the lime mud nor the bottom ash contributed to the flexibility of the slurry. On the contrary, the paper sludge and wood chips significantly optimized the slurries. In order to strike a balance between the compres- sive strength and the flexibility proportion, 20% of the waste substitution should be preliminarily determined as the suitable proportion. (3) Considering the possibility of adding wood chips as decoration materials, 15% of wood chips and 5% of paper sludge are appropriate proportions in the mixture. (4) For the alkali-activated mixture of wastes and BFS, 6% of AE was the best ratio for the activator with the silicate modulus (Ms) fixed at 0.9. Author Contributions: T.Y.: Conceptualization, Methodology, Formal analysis, Investigation, Data curation, Writing—original draft. S.-R.L.: Funding acquisition, Project administration, Supervision, Resources, Writing—review and editing. W.-Y.K.: Supervision, Resources, Writing—review and editing. All authors have read and agreed to the published version of the manuscript. Funding: This research was funded by Ministry of Education of Taiwan, grant number H108-AA09. Data Availability Statement: https://www.researchgate.net/publication/364358812_data_for_Research_ on_Recycling_Various_Wastes_in_Papermaking_as_Eco-Friendly_Slurry (accessed on 18 September 2022). Acknowledgments: We thank the CHP for materials provision, and NCKU C-Hub for space and instruments. Conflicts of Interest: The authors declare no conflict of interest.
Nomenclature
BFS blast furnace slag SPW the single-type papermaking wastes PWM the paper waste mixture AE alkali equivalent Ms silicate modulus
W/B water-binder ratio wt.% weight percentage
References 1. Lombard, B. Cepi Preliminary Statistics Report 2021 ; Confederation of European Paper Industries: Brussels, Belgium, 2022; p. 2. Available online: https://www.cepi.org/statistics/ (accessed on 23 February 2022). 2. Kilinc, M.B. Epicellulyse XT (Xerophilic Technology)-Paper Mill Sludge (Waste) to Energy & amp; Organic Fertilizer. Available on- line: https://sdgs.un.org/partnerships/epicellulyse-xt-xerophilic-technology-paper-mill-sludge-waste-energyorganic-fertilizer (accessed on 18 September 2022). 3. Suhr, M.; Klein, G.; Kourti, I.; Gonzalo, M.R.; Santonja, G.G.; Roudier, S.; Sancho, L.D. Best Available Techniques (Bat) Reference Document for the Production of Pulp, Paper and Board ; Publications Office of the European Union: Luxembourg, 2015; Volume 906. 4. Monte, M.C.; Fuente, E.; Blanco, A.; Negro, C. Waste management from pulp and paper production in the European Union. Waste Manag. 2009 , 29 , 293–308. [CrossRef] [PubMed] 5. Gavrilescu, D. Energy from biomass in pulp and paper mills. Environ. Eng. Manag. J. 2008 , 7 , 537–546. [CrossRef]
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