Homogenization mathematical model of the cemented filling slurry with crushing waste rock and whole tailings
-
摘要: 针对废石全尾砂高浓度充填料浆管输易堵管及充填体分层的问题，开展减水剂、搅拌参数等对料浆均质性影响的试验及料浆均质化定量表征的研究。首先基于泌水−坍落度试验确定了聚羧酸系(PC)减水剂及其掺量区间，获得了PC作用下的料浆流变参数及充填体强度的变化规律。其次，通过图像处理技术分析搅拌料浆表面特征，明确了PC作用下搅拌时长及废尾比(废石与尾矿质量比)对料浆均质化的影响规律。最后，构建了废石全尾砂高浓度充填料浆的均质化模型。结果表明，PC作用能够降低料浆的屈服应力与塑性黏度系数，改善料浆流动性。合理掺量可以提升充填体的早期强度，但对28 d强度有削弱。料浆表面图像信息熵越高、黑色像素点占比越小，料浆均质化程度越高，且均质化程度随搅拌时长、废尾比的增大呈先增大后减小趋势。当PC的质量分数为0.26%~0.5%时，料浆均质化程度高，PC质量分数为0.5%时料浆屈服应力和塑性黏度达到最小值，分别为202.25 Pa和0.79 Pa·s。Abstract: Aiming at the problems of pipeline transportation blockage and filling body stratification caused by waste rock–unclassified tailings high-concentration slurry, the effects of superplasticizer and stirring parameters on the slurry homogenization were experimented with, and the quantitative characterization of slurry homogenization was explored. Initially, the polycarboxylate (PC) superplasticizer with the best suitability was screened out based on the bleeding-slump test, and the mathematical correlations of the slump and bleeding rate with the optimal superplasticizer dosage range were obtained by regression. The rheological properties of the slurry and the filling body strength were then determined at different PC superplasticizer dosages, and separate mathematical models for correlations of slurry rheological parameters and mechanical properties with superplasticizer dosage were built. Next, the slurry surface images under different stirring conditions were acquired with the Nikon D350 camera, and their information entropies were calculated. Meanwhile, the OTSU algorithm was used to perform image segmentation thresholding, and the images were binarized via Matlab, followed by a calculation of the proportion of black pixels in the binarized images. Further, the variation trends of image information entropy and black pixels proportion with PC superplasticizer, rock/tailing ratio (mass ratio of waste rock to unclassified tailings), and stirring time were derived. Finally, the homogenization mechanism in the waste rock–unclassified tailings filling slurry was revealed based on the PC superplasticizer’s regulatory role in fine particle absorption and dispersion, which was further validated by the relationship between the zeta potential of cement paste and the dosage of PC superplasticizer. On this basis, a quantitative model of slurry homogenization was developed based on the slump, bleeding rate, rheological properties, strength characteristics, and image information, and the optimal parameters of waste rock–unclassified tailings high-concentration filling slurry were obtained by multi-objective programming. The results show that the PC superplasticizer is highly suitable for the slurry, which can reduce its yield stress and plastic viscosity coefficient and improve its fluidity. When the dosage of PC superplasticizer is 0.50%, the yield stress and plastic viscosity of the slurry is reduced by 34.4% and 21.2%, respectively, in comparison to the case without superplasticizer. The slurry rheological properties conform to the Bingham plastic model. Increasing the PC superplasticizer dosage improves the early strength of the filling body and weakens the 28-d strength. Nonetheless, within the optimal dosage range, all the filling body strengths can meet the mine filling requirements. Slurry surface images with higher information entropy and a smaller proportion of black pixels indicate a higher degree of slurry homogenization. Moreover, the entropy value of slurry surface images tends to increase initially and then decrease with the prolonging of stirring time and the heightening of the rock/tailing ratio. When the rock/tailing ratio is constant, the proportion of black pixels is the largest at a stirring time of 3 min, followed by 5 min, and the smallest at 4 min. According to the quantitative model results of slurry homogenization, the reasonable dosage range of PC superplasticizer is 0.26%–0.5%, and the optimal stirring time is 4.3 min. The degree of homogenization is the best at a 0.5% dosage, at which point the slurry has a plastic viscosity μ of 0.79 Pa·s and a yield stress τ of 202.25 Pa.
-
图 1 粒径特征分布曲线. (a)废石; (b)尾砂
Figure 1. Characteristic distribution curve of particle size: (a)waste rock; (b)tailings
图 2 减水剂作用下料浆泌水−坍落变化情况
Figure 2. Changes of slurry bleeding and slump under the action of water-reducing agent
图 3 PC作用下料浆的剪切应力−剪切速率曲线
Figure 3. Shear stress-shear rate curve of slurry under the action of PC
图 4 PC掺量与屈服应力、塑性黏度的回归结果
Figure 4. Regression results of PC content, yield stress and plastic viscosity
图 5 充填体抗压强度曲线
Figure 5. Characterization curve of compressive strength of filling body
图 6 充填体抗压强度与影响因素关系曲面
Figure 6. Relationship between compressive strength of filling body and factors
图 7 不同PC质量分数条件下的搅拌试验结果. （a）ω=0；（b）ω=0.50%
Figure 7. Stirring test result with different ω: （a）ω=0；（b）ω=0.50%
图 8 搅拌时间与废尾比交互作用下表面图像信息熵变化. (a) ω=0(R2=0.9951)；(b) ω=0.5%(R2=0.9333)
Figure 8. Change of surface image information entropy under the interaction of mixing time and waste tail ratio:(a) ω=0(R2=0.9951) ； (b) ω=0.5%(R2=0.9333)
图 9 黑色像素点占比及二值化结果. (a)ω=0.5%；(b)ω=0
Figure 9. Proportion of black pixels and the result of binarization:(a) ω = 0.5% ； (b) ω = 0
图 10 全尾砂废石充填料浆中PC的均质化作用机理
Figure 10. Homogenization mechanism of polycarboxylate in filler slurry of whole tailings and waste rock
图 11 水泥净浆的Zeta电位与PC掺量的关系图
Figure 11. Relationship between the Zeta potential of the cement paste and the PC content
表 1 减水剂的性能指标
Table 1. Performance index of water-reducing agent
Type pH Cl− content/% Na2SO4 content/% PC 6.20 0.06 2.60 FDN 7.00–9.00 ≤1.00 ≤5.00 AK 9.72 0.28 0.74 
下载: 导出CSV
表 2 掺PC减水剂胶结体强度测试结果
Table 2. Strength test results of cement mixed with PC water-reducing agen
No. ω/% Compressive strength, σ/MPa 3 d 7 d 28 d 1 0.00 2.35 3.77 6.54 2 0.10 3.11 5.14 7.72 3 0.20 3.46 4.97 6.31 4 0.30 3.26 5.09 5.77 5 0.40 2.78 4.42 5.59 6 0.50 2.43 3.95 5.26
下载: 导出CSV
表 3 不同条件下料浆表面单元及整体图像的熵值
Table 3. Entropy of the surface unit and the overall image of the slurry under different conditions
No. Time/min Waste totail ratio ω = 0 ω = 0.50% Maximum entropy
unitMinimum
entropy unitAverage unit entropy Overall
imageMaximum entropy
unitMinimum entropy
unitAverage unit entropy Overall
image1 3 6:4 3.96 3.73 3.85 57.74 4.20 3.96 4.08 61.18 2 3 7:3 3.98 3.75 3.87 58.00 4.21 3.92 4.06 60.95 3 3 5:5 3.97 3.70 3.84 57.59 4.17 3.93 4.05 60.80 4 4 6:4 4.07 3.85 3.96 59.41 4.27 4.04 4.16 62.36 5 4 7:3 4.06 3.83 3.95 59.18 4.27 4.02 4.15 62.21 6 4 5:5 4.02 3.78 3.90 58.51 4.23 4.00 4.11 61.72 7 5 6:4 4.01 3.77 3.89 58.37 4.26 4.00 4.13 61.98 8 5 7:3 4.00 3.76 3.88 58.18 4.19 3.95 4.07 61.01 9 5 5:5 4.04 3.81 3.92 58.86 4.21 3.96 4.09 61.29
下载: 导出CSV
表 4 料浆表面图像二值化后的黑色像素点占比
Table 4. Percentage of black pixels after binarization of the slurry surface image
No. Time/min Waste to tail ratio Percentage of black pixels (h)/% ω=0 ω = 0.50% 1 3 5:5 40.33 62.23 2 3 6:4 35.15 63.65 3 3 7:3 42.43 58.55 4 4 5:5 16.46 14.40 5 4 6:4 13.98 13.85 6 4 7:3 15.22 14.64 7 5 5:5 23.25 19.44 8 5 6:4 21.54 20.05 9 5 7:3 21.94 21.85
下载: 导出CSV
-
参考文献
[1] Li X B, Zhou J, Wang S F, et al. Review and practice of deep mining for solid mineral resources. Chin J Nonferrous Met, 2017, 27(6): 1236李夕兵, 周健, 王少锋, 等. 深部固体资源开采评述与探索. 中国有色金属学报, 2017, 27(6):1236 [2] Cai M F. Development of China's metal mines in the 21st century. China Min Mag, 2001, 10(1): 11 doi: 10.3969/j.issn.1004-4051.2001.01.005蔡美峰. 中国金属矿山21世纪的发展前景评述. 中国矿业, 2001, 10(1):11 doi: 10.3969/j.issn.1004-4051.2001.01.005 [3] Cheng H Y, Wu A X, Wu S C, et al. Research status and development trend of solid waste backfill in metal mines. Chin J Eng, 2022, 44(1): 11程海勇, 吴爱祥, 吴顺川, 等. 金属矿山固废充填研究现状与发展趋势. 工程科学学报, 2022, 44(1):11 [4] Wu A X, Yang Y, Cheng H Y, et al. Status and prospects of paste technology in China. Chin J Eng, 2018, 40(5): 517吴爱祥, 杨莹, 程海勇, 等. 中国膏体技术发展现状与趋势. 工程科学学报, 2018, 40(5):517 [5] Wang X M, Zhao J W, Zhang Q L, et al. Optimal mining model of transition from open-pit to underground mining. J Central South Univ (Sci Technol) , 2012, 43(4): 1434王新民, 赵建文, 张钦礼, 等. 露天转地下最佳开采模式. 中南大学学报(自然科学版), 2012, 43(4):1434 [6] Ben-Awuah E, Richter O, Elkington T, et al. Strategic mining options optimization: Open pit mining, underground mining or both. Int J Min Sci Technol, 2016, 26(6): 1065 doi: 10.1016/j.ijmst.2016.09.015 [7] Wu A X, Li H, Cheng H Y, et al. Status and prospects of research on the rheology of paste backfill using unclassified tailings (Part 2): Rheological measurement and prospects. Chin J Eng, 2021, 43(4): 451吴爱祥, 李红, 程海勇, 等. 全尾砂膏体流变学研究现状与展望(下): 流变测量与展望. 工程科学学报, 2021, 43(4):451 [8] Ruan Z E, Wu A X, Wang Y M, et al. Multiple response optimization of key performance indicators of cemented paste backfill of total solid waste. Chin J Eng, 2022, 44(4): 496阮竹恩, 吴爱祥, 王贻明, 等. 全固废膏体关键性能指标的多目标优化. 工程科学学报, 2022, 44(4):496 [9] Mou H W, Lv W S, Yang P. Application of a spiral pipe in a low stowing gradient backfilling pipeline and amendment of stowing gradient. Chin J Eng, 2016, 38(8): 1069牟宏伟, 吕文生, 杨鹏. 螺旋管在小倍线充填中的应用及充填倍线公式修正. 工程科学学报, 2016, 38(8):1069 [10] Zhu L P, Ni W, Gao S J, et al. Adaptability and early hydration of a cementing agent prepared with red mud, slag, flue gas desulphurization gypsum and a little cement clinker. Chin J Eng, 2015, 37(4): 414祝丽萍, 倪文, 高术杰, 等. 赤泥−矿渣−脱硫石膏−少熟料胶结剂的适应性及早期水化. 工程科学学报, 2015, 37(4):414 [11] Wang J D, Wu A X, Wang Y M, et al. Evaluation model and experimental study for segregation resistance of paste with coarse aggregate. J China Univ Min Technol, 2016, 45(5): 866王建栋, 吴爱祥, 王贻明, 等. 粗骨料膏体抗离析性能评价模型与实验研究. 中国矿业大学学报, 2016, 45(5):866 [12] Kou Y P, Qi Z J, Sheng Y H, et al. Study on time-dependent rheological parameters of unclassified tailings cemented slurry under motion state. Nonferrous Met Min Sect, 2019, 71(1): 15寇云鹏, 齐兆军, 盛宇航, 等. 运动状态下全尾砂胶结料浆流变参数时变性研究. 有色金属(矿山部分), 2019, 71(1):15 [13] Li X, Li C P, Yan B H, et al. Analysis of the influence factors of paste stirring based on discrete element method. Met Mine, 2021(3): 19李雪, 李翠平, 颜丙恒, 等. 基于离散元的膏体搅拌影响因素分析. 金属矿山, 2021(3):19 [14] Yan Z P, Yin S H, Yan R F, et al. The effect of mixing time on the homogeneity and early strength of the coarse aggregate paste. Chin J Nonferrous Met,http://kns.cnki.net/kcms/detail/43.1238.TG.20210824.1021.002.html闫泽鹏, 尹升华, 严荣富, 等. 搅拌时间对粗骨料膏体均质性及早期强度的影响. 中国有色金属学报,http://kns.cnki.net/kcms/detail/43.1238.TG.20210824.1021.002.html [15] Wang H J, Yang L H, Wang Y, et al. Multi-scale materials’ dispersive mixing technology of unclassified tailings Paste. J Wuhan Univ Technol, 2017, 39(12): 76王洪江, 杨柳华, 王勇, 等. 全尾砂膏体多尺度物料搅拌均质化技术. 武汉理工大学学报, 2017, 39(12):76 [16] Yang Z Q, Wang Y Q, Gao Q, et al. Research on pumping water reducing agent affecting on the strength of backfilling body and workability of paste slurry with tailing and rod grinding sand. J Fuzhou Univ Nat Sci, 2015, 43(1): 129杨志强, 王永前, 高谦, 等. 泵送减水剂对尾砂-棒磨砂膏体料浆和易性与充填体强度影响研究. 福州大学学报(自然科学版), 2015, 43(1):129 [17] Cao E X. Research on Mechanism of Polycarboxylate Superplasticizer on Rheological Properties of Cement Paste [Dissertation]. Beijing: Tsinghua University, 2011曹恩祥. 聚羧酸减水剂对水泥净浆体系流变性能的作用机理研究[学位论文]. 北京: 清华大学, 2011 [18] Jézéquel P H, Collin V. Mixing of concrete or mortars: Dispersive aspects. Cem Concr Res, 2007, 37(9): 1321 doi: 10.1016/j.cemconres.2007.05.007 [19] Gao J C, Cui X X, Shen Y F, et al. Fabrication of HDPE composites via a novel friction stir processing technology. J Thermoplast Compos Mater, 2019, 32(10): 1305 doi: 10.1177/0892705718796543 [20] Qian S S, Yao Y, Wang Z M, et al. Synthesis and mechanism of polyphosphate superplasticizer. J Chin Ceram Soc, 2021, 49(5): 910钱珊珊, 姚燕, 王子明, 等. 聚膦酸减水剂的合成、表征及机理. 硅酸盐学报, 2021, 49(5):910 [21] Dong Y. Research on Multi-Solid Waste Collaborative Comprehensive Utilization of Mining Backfill in Jinchuan Mine [Dissertation]. Beijing: University of Science and Technology Beijing, 2019董越. 多固废资源在金川矿山充填采矿中协同综合利用研究[学位论文]. 北京: 北京科技大学, 2019 [22] Basu P, Thomas B S, Gupta R C, et al. Properties of sustainable self-compacting concrete incorporating discarded sandstone slurry. J Clean Prod, 2021, 281: 125313 doi: 10.1016/j.jclepro.2020.125313 [23] Xiao C Y, Zhu W X. Threshold selection algorithm for image segmentation based on Otsu rule and image entropy. Comput Eng, 2007, 33(14): 188 doi: 10.3969/j.issn.1000-3428.2007.14.066肖超云, 朱伟兴. 基于Otsu准则及图像熵的阈值分割算法. 计算机工程, 2007, 33(14):188 doi: 10.3969/j.issn.1000-3428.2007.14.066 [24] Yang L H, Wang H J, Wu A X, et al. Status and development tendency of the full-tailings paste mixing technology. Met Mine, 2016(7): 34 doi: 10.3969/j.issn.1001-1250.2016.07.005杨柳华, 王洪江, 吴爱祥, 等. 全尾砂膏体搅拌技术现状及发展趋势. 金属矿山, 2016(7):34 doi: 10.3969/j.issn.1001-1250.2016.07.005 [25] Wang C Y, Zhao H, Dai Z H, et al. Effect of surfactant on the rheological properties of hydrophilic particle suspension. Chin J Appl Chem, 2021, 38(4): 398王春雨, 赵辉, 代正华, 等. 表面活性剂对亲水性颗粒悬浮液流变性的影响. 应用化学, 2021, 38(4):398 [26] Du X D, Liu M, Bi Y, et al. Effect of polymethyl carboxylic acid water reducing agent on zeta potential of cement slurry and its rheological properties// A Compilation of Excellent Papers of Cologne Cup 2016 on New Progress in Research and Application of Chemical Admixtures and Mineral Admixtures in China. Qingdao, 2016: 186杜小弟, 刘明, 毕耀, 等. 聚甲基羧酸减水剂对水泥浆体Zeta电位及其流变性影响 // 中国化学外加剂及矿物外加剂研究与应用新进展2016年科隆杯优秀论文汇编. 青岛, 2016:186 [27] Cao G S, Tong L, Hu Y, et al. Optimization of flocculant dosage by Zeta potential of the particles in sewage. J Daqing Petroleum Inst, 2009, 33(1): 17曹广胜, 佟乐, 胡仪, 等. 基于污水悬浮颗粒Zeta电位的絮凝剂用量优化. 大庆石油学院学报, 2009, 33(1):17 [28] Wu J Z, Beliakov G. Nonadditive robust ordinal regression with nonadditivity index and multiple goal linear programming. Int J Intell Syst, 2019, 34(7): 1732 doi: 10.1002/int.22119 [29] Sadeghi H, Moslemi F. A multiple objective programming approach to linear bilevel multi-follower programming. AIMS Math, 2019, 4(3): 763 doi: 10.3934/math.2019.3.763 -
点击查看大图
计量
- 文章访问数: 6
- HTML全文浏览量: 4
- PDF下载量: 0
- 被引次数: 0
