Abstract
To study the effect of mechanical treatments on the rheosedimentation behaviour of pulp fiber suspensions, the settling behaviour, gel point, compressive yield stress and hindered settling function of bleached softwood pulp with different beating degrees at low concentrations were investigated. Over the range of test concentrations, it was found that the settling rates for refined softwood pulps were slower than that without mechanical treatments, and the values of gel points increased approximately linearly with freeness; Both the compressive yield stresses and hindered settling functions of all pulp suspensions increased non-linearly with increasing crowding number, and the hindered settling function was found to be dependent on the crowding number through a power law relationship. Moreover, the compressive yield stresses for softwood pulp suspensions with mechanical treatment were higher than that without refining. However, the same tendency for hindered settling functions was observed only for suspension at crowding number more than 16. The rheosedimentation studies on softwood pulp suspensions revealed that fiber morphology has a great influence on the settling and compressive behaviour.
Similar content being viewed by others
References
Buratto B, Usher SP, Parris D, Scales PJ (2014) Wall effects during settling in cylinders. Colloids Surf A 449(1):157–169. https://doi.org/10.1016/j.colsurfa.2014.02.045
Celzard A, Fierro V, Kerekes R (2009) Flocculation of cellulose fibres: new comparison of crowding factor with percolation and effective-medium theories. Cellulose 16(6):983–987. https://doi.org/10.1007/s10570-009-9314-0
Derakhshandeh B, Kerekes RJ, Hatzikiriakos SG, Bennington CPJ (2011) Rheology of pulp fibre suspensions: a critical review. Chem Eng Sci 66(15):3460–3470. https://doi.org/10.1016/j.ces.2011.04.017
Derakhshandeh B, Vlassopoulos D, Hatzikiriakos SG (2012) Thixotropy, yielding and ultrasonic Doppler velocimetry in pulp fibre suspensions. Rheol Acta 51(3):201–214. https://doi.org/10.1007/s00397-011-0577-7
Feist M, Nirschl H, Wagner R, Hirsch G, Schabel S (2007) Experimental results for the settling behaviour of particle-fiber mixtures. Phys Sep Sci Eng 2007(1):3–9. https://doi.org/10.1155/2007/91740
Fišerová M, Gigac J, Boháček Š (2010) Influence of fibre characteristics on rheosedimentation properties of kraft pulp suspensions. Wood Res Slovak 55(2):63–70
Hubbe MA (2007) Flocculation and redispersion of cellulosic fiber suspensions: a review of effects of hydrodynamic shear and polyelectrolytes. BioResources 2(2):296–331. https://doi.org/10.15376/biores.2.2.296-331
Huber P, Carré B, Petitconil M (2008) The influence of TMP fibre flexibility on flocculation and formation. BioResources 3(4):1218–1227. https://doi.org/10.15376/biores.3.4.1218-1227
Kerekes RJ, Schell CJ (1992) Characterization of fibre flocculation by a crowding factor. J Pulp Pap Sci 18(1):32–38
Kretser RG, Boger DV, Scales PJ (2003) Compressive rheology: an overview. In: Binding DM, Walters K (eds) Rheology reviews. British Society of Rheology, Aberystwyth, pp 125–165
Kumar P, Ramarao BV (1991) Enhancement of the sedimentation rates of fibrous suspensions. Chem Eng Commun 108(1):381–401. https://doi.org/10.1080/00986449108910968
Lasseuguette E, Roux D, Nishiyama Y (2008) Rheological properties of microfibrillar suspension of TEMPO-oxidized pulp. Cellulose 15(3):425–433. https://doi.org/10.1007/s10570-007-9184-2
Lester DR, Usher SP, Scales PJ (2005) Estimation of the hindered settling function R(ϕ) from batch-settling tests. AIChE J 51(4):1158–1168. https://doi.org/10.1002/aic.10333
Martinez DM, Buckley K, Jivan S, Lindstrom A, Thiruvengadaswamy R, Olson JA, Ruth TJ, Kerekes RJ (2001) Characterizing the mobility of papermaking fibres during sedimentation. In: Baker CF (ed) The science of papermaking: transactions of the 12th fundamental research symposium, Oxford. The Pulp and Paper Fundamental Research Society, Bury, pp 225–254
Marton R, Robie JD (1969) Characterization of mechanical pulps by a settling technique. Tappi J 52(12):2400–2406
Miles KB, Karnis A (1991) The response of mechanical and chemical pulps to refining. Tappi J 74(1):57–64
Mosse WK, Boger DV, Simon GP, Garnier G (2012) Effect of cationic polyacrylamides on the interactions between cellulose fibers. Langmuir 28(7):3641–3649. https://doi.org/10.1021/la2049579
Nasser MS, James AE (2006) Settling and sediment bed behaviour of kaolinite in aqueous media. Sep Purif Technol 51(1):10–17. https://doi.org/10.1016/j.seppur.2005.12.017
Nasser MS, James AE (2007) Effect of polyacrylamide polymers on floc size and rheological behaviour of kaolinite suspensions. Colloids Surf A 301(1–3):311–322. https://doi.org/10.1016/j.colsurfa.2006.12.080
Nie S, Zhang K, Lin X, Zhang C, Yan D, Liang H, Wang S (2018) Enzymatic pretreatment for the improvement of dispersion and film properties of cellulose nanofibrils. Carbohyd Polym 181:1136–1142. https://doi.org/10.1016/j.carbpol.2017.11.020
Sell NJ, Doshi MR, Hawes JM (1988) Sedimentation behavior of various pulp fibers. Chem Eng Commun 73(1):217–225. https://doi.org/10.1080/00986448808940443
Sha J, Nikbakht A, Wang C, Zhang H, Olson J (2015) The effect of consistency and freeness on the yield stress of chemical pulp fibre suspensions. BioResources 10(3):44–59. https://doi.org/10.15376/biores.10.3.4287-4299
Sha J, Zhang F, Zhang H (2016) Thixotropic flow behaviour in chemical pulp fibre suspensions. BioResources 11(2):3481–3493. https://doi.org/10.15376/biores.11.2.3481-3493
Soszysnki RM, Kerekes RJ (1988) Elastic interlocking of nylon fibres suspended in liquid. Part 2. Process of interlocking. Nordic Pulp Pap Res J 3(4):180–184. https://doi.org/10.3183/npprj-1988-03-04-p180-184
Usher SP (2002) Suspension dewatering: characterisation and optimization. Dissertation, University of Melbourne
Usher SP, Scales PJ (2005) Steady state thickener modelling from the compressive yield stress and hindered settling function. Chem Eng J 111(2–3):253–261. https://doi.org/10.1016/j.cej.2005.02.015
Varanasi S, He R, Batchelor W (2013) Estimation of cellulose nanofibre aspect ratio from measurements of fibre suspension gel point. Cellulose 20(4):1885–1896. https://doi.org/10.1007/s10570-013-9972-9
Acknowledgments
This research was supported by grants from the Open Foundation of Guangxi Key Laboratory of Clean Pulp & Papermaking and Pollution Control (No. ZR201704), the Natural Science Foundation of Guangxi (No. 2017GXNSFBA198217), and the Scientific Research Foundation of Guangxi University (Nos. 20170390, 20170232).The authors also wish to thank Chunpei Lu for her valuable help with pulp refining.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interest
The authors declare that they have no conflict of interest.
Rights and permissions
About this article
Cite this article
Li, W., Yang, Y., Sha, J. et al. The influence of mechanical refining treatments on the rheosedimentation properties of bleached softwood pulp suspensions. Cellulose 25, 3609–3618 (2018). https://doi.org/10.1007/s10570-018-1808-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10570-018-1808-1