金川膏体管道输送特性环管试验与减阻技术

Pipe-loop Test for Transportation Characteristics of Paste in Jinchuan Mine and Corresponding Drag Reduction Technology

在金川矿山膏体充填系统开展了泵压管道输送特性环管试验,针对不添加水泥和胶砂比为1∶4的2种全尾砂膏体进行了管道输送阻力试验。结果表明,膏体输送平均流速为1.2 m/s时,质量浓度为72.2%,75.8%和78.9%的管输阻力分别为10,19和33 k Pa/m;胶砂比为1∶4、质量浓度为78.9%的胶结全尾砂膏体管输阻力为12.5 k Pa/m。针对全尾砂与棒磨砂配比分别为6∶4、5∶5和4∶6的3种混合骨料,开展了膏体管输阻力试验,结果表明,在平均流速为1.2 m/s、管输阻力不大于15 k Pa/m的条件下,3种混合骨料膏体可泵送膏体质量浓度分别为80%,79%和81%;试验结果还显示,质量浓度相差1%,管道阻力损失相差50%~100%,可见膏体管输阻力对浓度变化十分敏感;3种配比的混合骨料膏体塌落度大于15 cm,满足膏体泵压输送要求。膏体减阻试验结果揭示,添加水泥材料1.5%的YNB型泵送剂,膏体管输减阻效率可达到68.6%,相应的膏体塌落度增加88%。

Pipe-loop testing was conducted for the paste backfilling system in Jinchuan Mine,for investigating the pump-pressured pipeline transportation characteristics. The pipeline transportation drag was tested for 2 kinds of total tailings paste backfill,one without cement and another with cement-sand ratio at 1∶ 4. Results show that pipeline drags of 10,19 and 33 k Pa/m were measured for the paste with mass concentration of 72. 2%,75. 8% and 78. 9%,respectively,at an average flowing velocity of 1. 2 m/s,while the pipeline drag was 12. 5 k Pa/m for the cemented total tailings paste with cement-sand ratio at 1∶ 4 and mass concentration of 78. 9%. With 3 kinds of mixed aggregate,which was prepared with total tailings and rod mill sand at the ratio of 6∶ 4,5∶ 5 and 4∶ 6,respectively,tests were conducted to measure their pipeline transportation drag. It is showed that in order to obtain an average flowing velocity of 1. 2 m/s,with the pipeline drag less than 15 k Pa/m,those 3 kinds of mixed paste to be transported shall be prepared with the mass concentration at 80%,79% and 81% respectively. It is also found that 1% difference in the mass concentration can lead to the difference in drag loss ranging 50% ~ 100%,indicating the pipeline transportation drag of paste extremely susceptible to the concentration. This 3 kinds of mixed paste all have a slump more than 15 cm,meeting the requirement for pumping transportation. The drag reduction testing showed that the drag reduction efficiency for the paste pipeline transportation reached 68. 6% and the corresponding slump of past was up to 88% after the addition of YNB type pumping agent containing 1. 5% cement.