全尾砂新型充填胶凝材料在月山铜矿的应用研究

根据月山铜矿的充填胶凝材料选择和充填料配比参数设计,开展了全尾砂新型胶凝材料胶结充填体和水泥胶结充填体的强度对比试验。通过研究全尾砂的基本物理力学特性,并在此基础上采用全面试验法测试了不同灰砂比、不同料浆浓度全尾砂充填体试块单轴抗压强度。结果表明:该铜矿全尾砂的中值粒径为d50=0.0426mm,大于0.074mm的尾砂占36.8%,全尾砂颗粒细;灰砂比1∶6、浓度70%、28d养护龄期的水泥胶结试块抗压强度为1.32MPa,而相同条件下新型胶凝材料胶结试块抗压强度是水泥胶结试块的3.53倍即4.66 MPa。因此,提出了适合矿山的胶结充填参数:推荐充填料浆浓度68%~70%,新型胶凝材料与全尾砂之比为1∶6~1∶8进行工业充填试验。工业试验结果表明,1#和2#钻孔充填体试样强度均能够满足月山铜矿对充填技术和充填质量的要求,且强度仍有富余,建议矿山进一步优化充填料配比,减少胶凝材料用量,从而节约充填成本。

Application of a new cementing material for total tailings backfill in Yueshan Copper Mine

According to the selection of backfill cementing materials and the parameter design of backfill mixing ratio in the Yueshan copper mine, the comparison tests of backfill strength were carried out, by using cement or a new cementing material in total tailings. The basic physical and mechanical properties of total tailings were firstly studied; and based on this, using the method of comprehensive tests, the experiments of uniaxial compressive strength of total tailing backfill samples with different cement-tailing ratio and slurry concentrationwere analyzed. The results indicated that the median particle size of total tailings, d50 was 0.0426 mm, and the percentage of tailings particle size larger than 0.074 mm was only 36.8%, hence, the total tailings were fine one. By using general cement, with the cement-sand ratio of 1:6 and the pulp density of 70%, the uniaxial compressive strength of cemented backfill was 1.32 MPa for sample curing time of 28 d; while by using a new cementing material which was 4.66 MPa, i.e., 3.53 times as much as that of by using general cement. It was recommended to carry out industrial filling tests with slurry concentration of 68%~70% and new cementing material-sand ratio of 1:6~1:8. The results of industrial tests showed that the strength of backfill samples in boreholes No.1 and No.2 can meet the requirements of filling techniques and the mining operationof Yueshan copper mine, meanwhile the strength was still surplus. In order to reduce the amount of new cementing materials in backfill and thus to save the filling cost, it was alsosuggested that the new cementing material-sand ratio should be further optimized.