Jin Junyu, Jin Xufeng, Wang Yu, Qiao Fang
College of Coal Engineering, Shanxi Datong University, Datong 037009, China.
The Cultivation Base of Shanxi Key Laboratory of Coal Mine Water Jet Technology and Equipment, Shanxi Datong University, Datong 037009, China.
Materials (Basel). 2025 Jul 23;18(15):3461. doi: 10.3390/ma18153461.
HPMC, regulating slurry properties, is widely used in cement-based materials. Research on the application of HPMC in gangue slurry is still in its early stages. Moreover, the interactive effects of various factors on gangue slurry performance have not been thoroughly investigated. The work examined the effects of slurry concentration (X), maximum gangue particle size (X), and HPMC dosage (X) on slurry performance using response surface methodology (RSM). The microstructure of the slurry was characterized via scanning electron microscopy (SEM) and polarized light microscopy (PLM), while low-field nuclear magnetic resonance (LF-NMR) was employed to analyze water distribution. Additionally, industrial field tests were conducted. The results are presented below. (1) X and X exhibited a negative correlation with layering degree and slump flow, while X showed a positive correlation. Slurry concentration had the greatest impact on slurry performance, followed by maximum particle size and HPMC dosage. HPMC significantly improved slurry stability, imposing the minimum negative influence on fluidity. Interaction terms XX and XX significantly affected layering degree and slump flow, while XX significantly affected layering degree instead of slump flow. (2) Derived from the RSM, the statistical models for layering degree and slump flow define the optimal slurry mix proportions. The gangue gradation index ranged from 0.40 to 0.428, with different gradations requiring specific slurry concentration and HPMC dosages. (3) HPMC promoted the formation of a 3D floc network structure of fine particles through adsorption-bridging effects. The spatial supporting effect of the floc network inhibited the sedimentation of coarse particles, which enhanced the stability of the slurry. Meanwhile, HPMC only converted a small amount of free water into floc water, which had a minimal impact on fluidity. HPMC addition achieved the synergistic optimization of slurry stability and fluidity. (4) Field industrial trials confirmed that HPMC-optimized gangue slurry demonstrated significant improvements in both stability and flowability. The optimized slurry achieved blockage-free pipeline transportation, with a maximum spreading radius exceeding 60 m in the goaf and a maximum single-borehole backfilling volume of 2200 m.
羟丙基甲基纤维素（HPMC）可调节浆料性能，在水泥基材料中广泛应用。关于HPMC在煤矸石浆料中的应用研究仍处于早期阶段。此外，各种因素对煤矸石浆料性能的交互作用尚未得到充分研究。本研究采用响应面法（RSM）考察了浆料浓度（X）、最大煤矸石粒径（X）和HPMC用量（X）对浆料性能的影响。通过扫描电子显微镜（SEM）和偏光显微镜（PLM）对浆料微观结构进行表征，同时采用低场核磁共振（LF-NMR）分析水分分布。此外，还进行了工业现场试验。结果如下：（1）X和X与分层度和坍落度呈负相关，而X呈正相关。浆料浓度对浆料性能影响最大，其次是最大粒径和HPMC用量。HPMC显著提高了浆料稳定性，对流动性的负面影响最小。交互项XX和XX对分层度和坍落度有显著影响，而XX对分层度有显著影响，对坍落度无显著影响。（2）根据RSM，分层度和坍落度的统计模型确定了最佳浆料配合比。煤矸石级配指数范围为0.40至0.428，不同级配需要特定的浆料浓度和HPMC用量。（3）HPMC通过吸附桥联作用促进细颗粒三维絮凝网络结构的形成。絮凝网络的空间支撑作用抑制了粗颗粒的沉降，增强了浆料的稳定性。同时，HPMC仅将少量自由水转化为絮凝水，对流动性影响最小。添加HPMC实现了浆料稳定性和流动性的协同优化。（4）现场工业试验证实，HPMC优化的煤矸石浆料在稳定性和流动性方面均有显著改善。优化后的浆料实现了无堵塞管道输送，在采空区最大扩展半径超过60 m，最大单孔回填量为2200 m。
