全尾砂高浓度胶结充填的环管试验

为探明全尾砂高浓度充填料浆的灰砂比、浓度和流速对管道阻力的影响规律，预测工业充填管道阻力，开展中试规模环管试验。根据管壁切应力与剪切速率关系建立管道阻力预测模型，利用灰关联法分析各因素对管道阻力的影响强弱，通过线性回归获取料浆流变参数。结果表明，管道阻力对料浆浓度的变化最为敏感，随浓度增加成二次函数增长。料浆流速对管道阻力的影响仅次于浓度，层流输送时管道阻力随流速增加成线性增长。灰砂比对管道阻力的影响有双重性，灰砂质量比小于1∶8时胶凝材料的黏结作用占主导并增加管道阻力，反之胶凝材料的润滑作用占主导并降低管道阻力。环管试验得到的料浆流变参数明显小于流变仪测试结果且更接近工程实际，管道阻力预测模型的误差小于10%。 

Loop test study on the high-concentration cemented filling of full tailings

The high-concentration slurry prepared from full tailings used for mine backfilling can effectively eliminate the disasters caused by underground voids and tailing ponds. Using pipelines to transport filling slurry is the most efficient way, and the pipe resistance is one of the most important parameters. Presently, the loop test method for studying the pipe transportation parameters of filling slurry is closest to engineering reality. To determine the influence of the cement-sand ratio, concentration, and flow velocity of the high-concentration filling slurry prepared from full tailings on the pipe resistance and predict the resistance of industrial filling pipelines, pilot-scale loop tests were performed. A pipe resistance prediction model was established based on the relationship between the shear stress and the shear rate at the pipe wall. The gray correlation method was used to analyze the influence of various factors on the pipe resistance, and the rheological parameters of filling slurry were obtained by linear regression. The results show that the pipe resistance is most sensitive to the mass concentration of filling slurry and increases quadratically. The flow velocity of filling slurry has the second-greatest effect on pipe resistance, and the resistance increases linearly with flow velocity in laminar flow. The cement-sand ratio of filling slurry has a dual effect on the pipe resistance. When the cement-sand ratio is less than 1∶8, the cohesion effect of the cementing material is dominant and increases the pipe resistance. On the contrary, the lubrication effect of the cementing material is dominant and reduces the pipe resistance. The rheological parameters of filling slurry obtained by the loop test are much smaller than those obtained by the rheometer, and the loop test method is more reliable. The error of the pipe resistance prediction model is within 10%.