Paste-like cemented backfilling technology and rheological characteristics analysis based on jigging sands

Abstract

To make backfilling body meet strength requirement, physical-chemical evaluation and proportioning tests were conducted on several backfilling materials. Jigging sands, #32.5 cement and fly ash were determined as backfilling aggregate, binding material and modified material, respectively. An optimized proportion of backfilling materials with a solid mass fraction of 78% and cement: fly ash: jigging sands mass ratio of 1:2:14, was suggested to Jiangan Pyrite Mine, China. The slurry made by optimized proportion produced obvious shear thinning phenomena, and was confirmed as paste-like slurry. To analyze its rheological characteristics, L-type pipeline test and Haake VT550 rotational viscometer test were conducted. Bingham and Casson fluid models were applied to several paste-like slurry samples to simulate flow and stress states; Casson fluid model was proved to have better simulation effect on paste-like slurry with shear thinning phenomena; rheological parameters of backfilling slurry made by suggested proportion were measured. Initial yield stress, average apparent viscosity and limiting viscosity are 55.35 Pa, 1.216 Pa·s and 0.48 Pa·s, respectively. Compared with Bingham fluid model, Casson fluid model has a better simulation effect on paste-like slurry with shear thinning phenomena, through calculating the residual standard deviations.

Keywords

paste-like slurry / jigging sands / shear thinning / Casson fluid model / backfilling system

References

[1] WangX-m, ZhaoJ-w, XueJ-h, YuG-feng. Features of pipe transportation of paste-like backfilling in deep mine [J]. Journal of Central South University of Technology, 2011, 18(5): 1413-1417

[2] WangX-m, GuD-s, ZhangQ-liTheory and technology of deep mine backfilling [M], 2010ChangshaCentral South University Press

[3] WangX-m, ZhaoB, ZhangQ-li. Cemented backfill technology based on phosphorous gypsum [J]. Journal of Central South University of Technology, 2009, 16(2): 285-291

[4] PengX, LiX-b, ZhangQ-l, WangX-min. Quality evaluation of layerlike backfilling and flow pattern of backfill slurry in stope [J]. Journal of Central South University of Technology, 2007, 14(4): 580-583

[5] ZhangQ-l, WangX-min. Performance of cemented coal gangue backfill [J]. Journal of Central South University, 2007, 14(2): 216-219

[6] ZhangQ-l, CuiJ-q, ZhengJ-j, WangX-m, WangX-lai. Wear mechanism and serious wear position of casing pipe in vertical backfill drill-hole [J]. Transactions of Nonferrous Metals Society of China, 2011, 21(11): 2503-2507

[7] WangX-m, ZhangD-m, ZhangQ-l, ZhaoBin. Pipeline self-flowing transportation property of paste based on FLOW-3D software in deep mine [J]. Journal of Central South University: Science and Technology, 2011, 42(7): 2102-2108

[8] ZhangQ-l, HuG-y, WangX-min. Hydraulic calculation of gravity transportation pipeline system for backfill slurry [J]. Journal of Central South University of Technology, 2008, 15(5): 645-649

[9] WangX-m, LiJ-x, XiaoZ-z, XiaoW-guo. Rheological properties of tailing paste slurry [J]. Journal of Central South University of Technology, 2004, 11(1): 75-79

[10] WangX-m, ZhaoB, ZhangQ-l, XuD-sheng. Cemented backfilling technology with unclassified tailings based on vertical sand silo [J]. Journal of Central South University of Technology, 2008, 15(6): 801-807

[11] ChenJ-l, LiuC-jian. Structural flow of Casson fluids and determination of Casson rheological parameters [J]. Acta Petrolei Sinica, 1982, 4(2): 69-80

[12] NadeemS, HaqR U L, AkbarN S, KhanZ H. MHD three dimensional flow of Casson fluid past a porous linearly stretching sheet [J]. Alexandria Eng J, 2013, 52(4): 577-82

[13] DashR K, MehtaK N, JayaramanG. Casson fluid flow in a pipe filled with a homogeneous porous medium [J]. Int J Eng Sci, 1996, 34(10): 1145-1156

[14] MukhopadhyayS. Casson fluid flow and heat transfer over a nonlinearly stretching surface [J]. Chinese Physics B, 2013, 22(70): 1-5

[15] NadeemS, RashidM, SherA N. Optimized analytical solution for oblique flow of a Casson nano fluid with convective boundary conditions [J]. Int J Therm Sci, 2014, 78(1): 90-100