Quantitative analysis of static yield stress variation in thickened tailings in compaction zone based on fine structure

Gezhong Chen; Cuiping Li; Zhuen Ruan; Raimund Bürger; Bingheng Yan; Chen Hu; Xue Li

doi:10.29393/ppudec-18qsrb70018

##article.authors##

Gezhong Chen Key Laboratory of the Ministry of Education of China for High efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 100083, PR China
Cuiping Li Key Laboratory of the Ministry of Education of China for High efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 100083, PR China
Zhuen Ruan Key Laboratory of the Ministry of Education of China for High efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 100083, PR China
Raimund Bürger Universidad de Concepción, Facultad de Ciencias Físicas y Matemática, Departamento de Ingeniería Matemática. Concepción, Chile.
Bingheng Yan Key Laboratory of the Ministry of Education of China for High efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 100083, PR China
Chen Hu Key Laboratory of the Ministry of Education of China for High efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 100083, PR China
Xue Li Key Laboratory of the Ministry of Education of China for High efficient Mining and Safety of Metal Mines, University of Science and Technology Beijing, Beijing 100083, PR China

DOI:

https://doi.org/10.29393/ppudec-18qsrb70018

Keywords:

tailings thickening, static yield stress, particle gradation, pore network model

Resumen

In the tailings thickening process, the poor flowability of the high concentration tailings slurry is likely to cause slurry hardening at the bottom of the vertical sand silo and rake blockage of the thickening machine, which will hurt the safe production of the mine and pollutes the environment. Therefore, the effect of slurry concentration on the static yield stress of the slurry with and without shear conditions was investigated using the full tailings of iron ore as raw material in this study. A comparative analysis of the static yield stress of thickened tailings and fresh mixing slurry with the same concentration and particle gradation was completed. The fine structural parameters of the thickening bed with and without shear were obtained by computed tomography. The effects of the structural parameters of the drainage channels in the thickening bed and the changes in the content of coarse particles with diameters ranging from 45 300 μm on the porosity of the thickening bed were analyzed. The effect of the fluctuation of the thickening bed's porosity on the slurry's static yield stress was also investigated. The results show that the thickened tailings is non homogeneous. The concentration of the slurry, the number and volume of coarse particles with diameters in the range of 75 300 μm increases with decreasing bed height. Analysis of the pore network model based on the structural equivalents of the drainage channels revealed that the pore volumes with equivalent diameters in the range of 50 250 μm are the largest and are the main storage space for water in the bed. Compared with the spherical pore structure, the stick throat channel structure is the main component of the drainage channel structure in the bed. The slurry rheology measurements show that the static yield stress of the thickened tailings is 5.3 61.3 times higher than the static yield stress of the fresh mixing slurry for the same slurry concentration and particle gradation. Our analyses revealed that the fluctuation of the porosity of the slurry also has an essential effect on the static yield stress of the thickened tailings. For the first time, we propose to use the coefficient of variation in bed porosity to quantify the difference in static yield stress values between thickened tailings and fresh mixing slurry and draw the necessary conclusion that the static yield stress of slurry decreases with the reduction of the coefficient of variation in bed porosity under the same conditions of slurry concentration and particle gradation. Based on the results of our research, it was applied in an iron ore mine in China, where vertical sand silo was used as the thickening equipment to solve the problem of slurry hardening in the silo and to achieve safe and efficient filling production.

Citas

Adiansyah, J.S., Rosano, M., Vink, S., Keir, G., 2015. A framework for a sustainable approach to mine tailings management: disposal strategies. J. Clean. Prod. 108, 1050 1062. https://doi.org/10.1016/j.jclepro.2015.07.139.

Adiguzel, D., Bascetin, A., 2019. The investigation of effect of particle size distribution on flow behavior of paste tailings. J. Environ. Manage. 243, 393 401. https://doi.org/10.1016/j.jenvman.2019.05.039.

Arjmand, R., Massinaei, M., Behnamfard, A., 2019. Improving flocculation and dewatering performance of iron tailings thickeners. J. Water Proc. Eng. 31, 100873. https://doi.org/10.1016/j.jwpe.2019.100873.

Asensi, E., Alemany, E., 2022. A hindered settling velocity model related to the fractal dimension and activated sludge flocs characteristics: Application to a sludge with a previous fragmentation and flocculation process. Sep. Purif. Technol. 300, 121812. https://doi.org/10.1016/j.seppur.2022.121812.

Boshrouyeh Ghandashtani, M., Costine, A., Edraki, M., Baumgartl, T., 2022. The impacts of high salinity and polymer properties on dewatering and structural characteristics of flocculated high solids tailings. J. Clean. Prod. 342, 130726. https://doi.org/10.1016/j.jclepro.2022.130726.

Brown, C.E., 1998. Coefficient of Variation, in: Brown, C.E. (Ed.), Applied Multivariate Statistics in Geohydrology and Related Sciences. Springer, Berlin, Heidelberg, pp. 155 157. https://doi.org/10.1007/978 3 642 80328 4_13.

Carissimi, E., Rubio, J., 2015. Polymer bridging flocculation performance using turbulent pipe flow. Miner. Eng. 70, 20 25. https://doi.org/10.1016/j.mineng.2014.08.019.

Chen, G., Li, C., Ruan, Z., Bürger, R., Gao, Y., Hou, H., 2023a. Structural evolution of bed drainage channels under the shear effect of the whole process of tailings thickening. Miner. Eng. 203, 108364. https://doi.org/10.1016/j.mineng.2023.108364.

Chen, G., Li, C., Ruan, Z., Bürger, R., Hou, H., 2024. A new permeability model of the compressible tailings thickening bed based on the throat structure parameters. Powder Technol. 433, 119263. https://doi.org/10.1016/j.powtec.2023.119263.

Chen, G., Li, C., Ruan, Z., Bürger, R., Hou, H., 2023b. Research on floc structure and physical properties based on pipeline flocculation. J. Water Proc. Eng. 53, 103627. https://doi.org/10.1016/j.jwpe.2023.103627.

Chen, Q., Zhou, H., Wang, Y., Wang, D., Zhang, Q., Liu, Y., 2023. Erosion wear at the bend of pipe during tailings slurry transportation: Numerical study considering inlet velocity, particle size and bend angle. Int. J. Miner. Metall. Mater. 30, 1608 1620. https://doi.org/10.1007/s12613 023 2672 z.

Fatt, I., 1956. The Network Model of Porous Media. Transactions of the AIME 207, 144 181. https://doi.org/10.2118/574 G.

Fawell, P.D., Nguyen, T.V., Solnordal, C.B., Stephens, D.W., 2021. Enhancing Gravity Thickener Feedwell Design and Operation for Optimal Flocculation through the Application of Computational Fluid Dynamics. Miner. Process. Extr. Metall. Rev. 42, 496 510. https://doi.org/10.1080/08827508.2019.1678156.

Gao, S., Li, W., Yuan, K., Rong, C., 2023. Properties and application of thixotropic cement paste backfill with molybdenum tailings. J. Clean. Prod. 391, 136169. https://doi.org/10.1016/j.jclepro.2023.136169.

Glotov, V.E., Chlachula, J., Glotova, L.P., Little, E., 2018. Causes and environmental impact of the gold tailings dam failure at Karamken, the Russian Far East. Eng. Geol. 245, 236 247. https://doi.org/10.1016/j.enggeo.2018.08.012.

He, H., Liu, Y., Zhang, A., Yang, Z., Liu, X., Yang, R., Tang, H., Li, Z., 2023. Kinetic modeling and experimental verification of a swirl flocculation enhanced reactor: A case study of coal chemical wastewater pretreatment. Sep. Purif. Technol. 326, 124852. https://doi.org/10.1016/j.seppur.2023.124852.

He, W., Chen, X., Xu, C., Zhou, C., Wang, C., 2023. Internal interaction between chemically pretreated polypropylene microplastics and floc growth during flocculation: Critical effect on floc properties and flocculation mechanisms. Sep. Purif. Technol. 306, 122710. https://doi.org/10.1016/j.seppur.2022.122710.

Huazhe, J., Shufei, W., Yixuan, Y., Xinming, C., 2020. Water recovery improvement by shearing of gravity thickened tailings for cemented paste backfill. J. Clean. Prod. 245, 118882. https://doi.org/10.1016/j.jclepro.2019.118882.

Jia, R., Zhang, B., He, D., Mao, Z., Chu, F., 2020. Data driven based self healing control of abnormal feeding conditions in thickening dewatering process. Miner. Eng. 146, 106141. https://doi.org/10.1016/j.mineng.2019.106141.

Jiao, H., Wu, Y., Wang, H., Chen, X., Li, Z., Wang, Y., Zhang, B., Liu, J., 2021. Micro scale mechanism of sealed water seepage and thickening from tailings bed in rake shearing thickener. Miner. Eng. 173, 107043. https://doi.org/10.1016/j.mineng.2021.107043.

Langlois, J.I., Cipriano, A., 2019. Dynamic modeling and simulation of tailing thickener units for the development of control strategies. Miner. Eng. 131, 131 139. https://doi.org/10.1016/j.mineng.2018.11.006.

Lèbre, É., Corder, G.D., Golev, A., 2017. Sustainable practices in the management of mining waste: A focus on the mineral resource. Miner. Eng. 107, 34 42. https://doi.org/10.1016/j.mineng.2016.12.004.

Leite, A. da M.C., Reis, É.L., 2020. Cationic starches as flocculants of iron ore tailing slime. Miner. Eng. 148, 106195. https://doi.org/10.1016/j.mineng.2020.106195.

Li, C., Chen, G., Ruan, Z., Bürger, R., Gao, Y., Hou, H., Wang, H., 2023a. Effect of variations in the polar and azimuthal angles of coarse particles on the structure of drainage channels in thickened beds. Int. J. Miner. Metall. Mater. 30, 1 13. https://doi.org/10.1007/s12613 023 2680 z.

Li, C., Li, X., Ruan, Z., Huang, Z., Wang, H., 2023b. Analysis of homogeneity and rheological properties of filling slurry during the mixing process through electrical resistance tomography. Powder Technol. 428, 118850. https://doi.org/10.1016/j.powtec.2023.118850.

Li, X., Li, C., Ruan, Z., Yan, B., Hou, H., Chen, L., 2022. Analysis of particle migration and agglomeration in paste mixing based on discrete element method. Constr. Build. Mater. 352, 129007. https://doi.org/10.1016/j.conbuildmat.2022.129007.

Lin, Z., Zhang, C., Hu, Y., Su, P., Quan, B., Li, X., Zhang, Z., 2023. Nano aluminum based hybrid flocculant: Synthesis, characterization, application in mine drainage, flocculation mechanism. J. Clean. Prod. 399, 136582. https://doi.org/10.1016/j.jclepro.2023.136582.

Liu, Y., Zhang, X., Jiang, W., Wu, M., Li, Z., 2021. Comprehensive review of floc growth and structure using electrocoagulation: Characterization, measurement, and influencing factors. Chem. Eng. J. 417, 129310. https://doi.org/10.1016/j.cej.2021.129310.

MacIver, M.R., Pawlik, M., 2022. A floc structure perspective on sediment consolidation in thickened tailings. Chem. Eng. Sci. 263, 118095. https://doi.org/10.1016/j.ces.2022.118095.

Mashifana, T., Sithole, T., 2021. Clean production of sustainable backfill material from waste gold tailings and slag. J. Clean. Prod. 308, 127357. https://doi.org/10.1016/j.jclepro.2021.127357.

Murujew, O., Geoffroy, J., Fournie, E., Socionovo Gioacchini, E., Wilson, A., Vale, P., Jefferson, B., Pidou, M., 2020. The impact of polymer selection and dose on the incorporation of ballasting agents onto wastewater aggregates. Water Res. 170, 115346. https://doi.org/10.1016/j.watres.2019.115346.

O’Shea, P., Qiao, G.G., Franks, G.V., 2010. Solid liquid separations with a temperature responsive polymeric flocculant: Effect of temperature and molecular weight on polymer adsorption and deposition. J. Colloid Interface Sci. 348, 9 23. https://doi.org/10.1016/j.jcis.2010.04.063.

Otus, N., 1979. A threshold selection method from gray level histograms. a threshold selection method from gray level histograms.

Peng, W., Lv, S., Cao, Y., Wang, W., Liu, S., Huang, Y., Fan, G., 2023. A novel pH responsive flocculant for efficient separation and recovery of Cu and Mo from secondary resources via selective flocculation flotation. J. Clean. Prod. 395, 136463. https://doi.org/10.1016/j.jclepro.2023.136463.

Qi, C., Fourie, A., 2019. Cemented paste backfill for mineral tailings management: Review and future perspectives. Miner. Eng. 144, 106025. https://doi.org/10.1016/j.mineng.2019.106025.

Qi, C., Fourie, A., Chen, Q., Tang, X., Zhang, Q., Gao, R., 2018. Data driven modelling of the flocculation process on mineral processing tailings treatment. J. Clean. Prod. 196, 505 516. https://doi.org/10.1016/j.jclepro.2018.06.054.

Rana, N.M., Ghahramani, N., Evans, S.G., Small, A., Skermer, N., McDougall, S., Take, W.A., 2022. Global magnitude frequency statistics of the failures and impacts of large water retention dams and mine tailings impoundments. Earth Sci. Rev. 232, 104144. https://doi.org/10.1016/j.earscirev.2022.104144.

Rico, M., Benito, G., Díez Herrero, A., 2008. Floods from tailings dam failures. J. Hazard. Mater. 154, 79 87. https://doi.org/10.1016/j.jhazmat.2007.09.110.

Ruan, Z., Wu, A., Bürger, R., Betancourt, F., Wang, Yiming, Wang, Yong, Jiao, H., Wang, S., 2021. Effect of interparticle interactions on the yield stress of thickened flocculated copper mineral tailings slurry. Powder Technol. 392, 278 285. https://doi.org/10.1016/j.powtec.2021.07.008.

Sabah, E., Erkan, Z.E., 2006. Interaction mechanism of flocculants with coal waste slurry. Fuel 85, 350 359. https://doi.org/10.1016/j.fuel.2005.06.005.

Tan, C.K., Bao, J., Bickert, G., 2017. A study on model predictive control in paste thickeners with rake torque constraint. Miner. Eng. 105, 52 62. https://doi.org/10.1016/j.mineng.2017.01.011.

Trampus, B.C., França, S.C.A., 2020. Performances of two flocculants and their mixtures for red mud dewatering and disposal based on mineral paste production. J. Clean. Prod. 257, 120534. https://doi.org/10.1016/j.jclepro.2020.120534.

Walch, H., von der Kammer, F., Hofmann, T., 2022. Freshwater suspended particulate matter Key components and processes in floc formation and dynamics. Water Res. 220, 118655. https://doi.org/10.1016/j.watres.2022.118655.

Wang, C., Sun, C., Liu, Q., 2020. Formation, breakage, and re growth of quartz flocs generated by non ionic high molecular weight polyacrylamide. Miner. Eng. 157, 106546. https://doi.org/10.1016/j.mineng.2020.106546.

Wang, H., Wang, X., Wu, A., Peng, Q., 2021. A wall slip pressure gradient model of unclassified tailings paste in pipe flow: Theoretical and loop test study. J. Non Newtonian Fluid Mech. 298, 104691. https://doi.org/10.1016/j.jnnfm.2021.104691.

Wu, A., Ruan, Z., Bürger, R., Yin, S., Wang, J., Wang, Y., 2020. Optimization of flocculation and settling parameters of tailings slurry by response surface methodology. Miner. Eng. 156, 106488. https://doi.org/10.1016/j.mineng.2020.106488.

Wu, A., Ruan, Z., Wang, J., 2022. Rheological behavior of paste in metal mines. Int. J. Miner. Metall. Mater. 29, 717 726. https://doi.org/10.1007/s12613 022 2423 6.

Xiong, Q., Baychev, T.G., Jivkov, A.P., 2016. Review of pore network modelling of porous media: Experimental characterisations, network constructions and applications to reactive transport. J. Contam. Hydrol. 192, 101 117. https://doi.org/10.1016/j.jconhyd.2016.07.002.

Ye, L., Wu, J., Huang, M., Yan, J., 2023. The role of suspended extracellular polymeric substance (EPS) on equilibrium flocculation of clay minerals in high salinity water. Water Res. 244, 120451. https://doi.org/10.1016/j.watres.2023.120451.

Yin, S., Shao, Y., Wu, A., Wang, H., Liu, X., Wang, Y., 2020. A systematic review of paste technology in metal mines for cleaner production in China. J. Clean. Prod. 247, 119590. https://doi.org/10.1016/j.jclepro.2019.119590.

Yu, W., Gregory, J., Campos, L., Li, G., 2011. The role of mixing conditions on floc growth, breakage and re growth. Chem. Eng. J. 171, 425 430. https://doi.org/10.1016/j.cej.2011.03.098.

Zhang, L., Wang, H., Wu, A., Klein, B., Guo, J., Zhang, X., 2022. A zone settling velocity function to characterize settling properties of suspensions in thickening applications. Miner. Eng. 177, 107386. https://doi.org/10.1016/j.mineng.2021.107386.

Zhu, L., Lyu, W., Mao, X., Zhao, Z., Yang, D., Zhang, H., Wang, K., Yang, P., Zeng, H., 2023. Effect of solution pH and polyethylene oxide concentration on surface/interface properties, flocculation and rheology of concentrated monodisperse ultrafine synthetic tailings slurry. Powder Technol. 430, 119002. https://doi.org/10.1016/j.powtec.2023.119002.

Zhu, L., Lyu, W., Yang, P., Wang, Z., 2020. Effect of ultrasound on the flocculation sedimentation and thickening of unclassified tailings. Ultrason. Sonochem. 66, 104984. https://doi.org/10.1016/j.ultsonch.2020.104984.