某稀土浮选尾矿高梯度超导磁选富集稀土矿物试验研究

Enrichment and Recovery of Rare Earth Minerals from Rare Earth Tailings by Superconducting High Gradient Magnetic Separation

针对某稀土矿选矿厂低品位难选尾矿,采用浮选方法进一步回收稀土时工艺流程长、成本高的技术难题,利用稀土矿物与脉石矿物之间微弱的磁性差异,采用高梯度超导磁选对该稀土尾矿进行富集,以提高稀土浮选入浮品位。研究结果表明,在电磁磁选介质为钢棒介质、磁场强度为0.4 T,高梯度超导磁选介质为钢毛介质、磁场强度为5.0 T时,通过高梯度超导磁选,可由REO品位为2.71%的稀土尾矿,最终获得产率为40.84%,REO品位为4.52%,回收率为67.35%的超导磁选精矿,抛除产率为22.39%,REO品位仅为0.94%的超导磁选尾矿,为后续稀土浮选提供了便利条件。

Superconducting high gradient magnetic separation(SC-HGMS)was introduced to elevate the rare earth(RE)grade in the fed minerals to a flotation operation that set-up to scavengingly recover RE from tailings discharged by another RE ore dressing plant,which is refractory to flotation,making the procedure tedious.The high gradient and very strong magnetic field in SC-HGMS can enrich RE in the tailings by discerning the small differences in magnetic susceptibility between RE minerals and gangue.The result showed that SC-HGMS,following a traditional high gradient magnetic pretreatment to remove irons,concentrates the RE minerals in the tailings from 2.71%to 4.52%with a recovery rate 67.35%and a yield 22.39%,at a condition that the pretreatment magnetic field strength is 0.4 T with a steel rod-fabricated matrix,the matrix in SC-HGMS is made of steel wool medium,the magnetic induction is 5.0 T.Thus,SC-HGMS provides superior substrates for the subsequent RE flotation.