云南某低品位高泥氧化锡矿石选矿试验

Beneficiation Tests of a Low-grade High Slime Tin Oxide Ore from Yunnan

云南某氧化锡矿Sn含量为0.170%、Fe含量为4.66%,泥化现象严重,属含铁、低品位、高泥难选锡矿石。为开发适宜的选别工艺流程并确定最佳工艺条件,在原矿性质研究的基础上开展了该矿石的选矿工艺研究。结果表明:①矿石中含锡0.170%,-0.019 mm细泥含量为12.74%,矿石中主要有用矿物为锡石,其次为褐铁矿,主要脉石矿物为石英;锡主要以锡石及酸溶锡的形式存在,选别难度较大。②螺旋溜槽抛尾是该矿适宜的预先抛尾方式,最佳工艺条件为洗矿分级后+0.212 mm粗粒磨矿至-0.074 mm占56.25%、螺旋溜槽截矿器精矿端宽度55 mm、螺旋溜槽给矿矿浆浓度30%、螺旋溜槽给矿矿浆速率3.0 m3/h,在此基础上可获得产率为32.65%、锡品位为0.424%、锡回收率为81.43%的溜槽精矿。③溜槽锡精矿摇床精选可获得锡品位较高的摇床锡精矿,摇床锡精矿强磁选除铁可获得高品位合格锡精矿。④矿石经"螺旋溜槽预先抛尾—摇床精选—强磁选除铁"的联合工艺流程,可获得产率为0.22%,锡品位41.860%,锡回收率为54.17%的锡精矿,及产率为0.68%,锡品位4.950%,锡回收率为19.80%的锡富中矿,锡累计回收率为73.97%,选矿产品含杂均不超标,较好地实现了该锡矿的分选。

The tin oxide ore from Yunnan with tin contents of 0.170% and iron contents of 4.66% is extremely sliming,which was considerated an iron-containing,low-grade,high slime and refractory tin ore. In order to develop appropriate dressing process and determine the optimal process conditions,the beneficiation process of the ore was studied based on study of properties of the ore. The results showed that: ① The ore contains 0.170% tin and the fine slime content of-0.019 mm is12.74%. The main valuable mineral in the tin ore is cassiterite,followed by limonite,and the main gangue mineral is quartz.The tin mainly exists in the form of cassiterite and acid soluble tin,which is difficult to separate. ② Pre-discarding with spiral chute is a suitable pre-discarding method for the ore,and the optimal technological conditions are the +0.212 mm washing fraction ground to-0.074 mm occupying for 56.25%,the cut pocket width for concentrate end of spiral chute of 55 mm,the feeding pulp concentration of spiral chute of 30%,and the feeding pulp speed of spiral chute of 3.0 m3/h. The chute concentrate with yield of 32.65%,tin grade of 0.424% and tin recovery rate of 81.43% was obtained under those conditions. ③ Higher grade tin concentrate could be obtained after cleaning with shaking table,and high grade qualified tin concentrate could be obtained after deironing by high magnetic separation with tin shaking table concentrate. ④ After the combined process flowsheet of pre-discarding with spiral chute,cleaning with shaking table and iron removal by high intensity magnetic separation,the tin concentrate with yield of 0.22%,tin grade of 41.860%,tin recovery rate of 54.17% and tin rich middling with yield of 0.68%,tin grade of 4.950%,tin recovery rate of 19.80% were obtained. The cumulative recovery rate of tin concentrate and tin rich middling was 73.97% and impurity content of products did not exceed the standard,which realized separation of tin ore.