Recovering limonite from Australia iron ores by flocculation-high intensity magnetic separation

Successful recovery of limonite from iron fines was achieved by using flocculation-high intensity magnetic separation （FIMS） and adding hydrolyzed and causticized flocculants according to the characteristic of iron fines. The separation results of the three iron samples are as follows： iron grade 66.77%- 67.98% and the recovery of iron 69.26%-70.70% by the FIMS process with flocculants. The comparative results show that under the same separation conditions the F1MS process can effectively increase the recovery of iron by 10. 97%- 15.73%. The flowsheet results confirm the reliability of the process in a SHP high intensity magnetic separator. The concentrate product can he used as raw materials for direct reduction iron-smelting. The hydrolyzed and causticized flocculants can selectively flocculate fine feebly-magnetic iron mineral particles to increase their apparent separation sizes. The larger the separation size, the stronger the magnetic force. By comparing the separation results of the three samples it is found that among the three samples the higher the limonite content, the better the separation result. This means that the separation result relates closely to the flocculation process and the adding pattern of the flocculant.

Magnetic field characteristics analysis of a single assembled magnetic medium using ANSYS software

The section shape of an assembled magnetic medium is the most important structural parameter of a high gradient magnetic separator, which directly affects the induction distribution and magnetic field gradient of the magnetic separator. In this study, equilateral triangle, square, hexagonal, octagon, dodecagon, and round shape sections of the assembled magnetic medium are chosen to study their influence on magnetic field distribution characteristics using the ANSYS analysis. This paper utilizes a single assembled magnetic medium to understand the relationship between the geometry of the assembled magnetic medium and its magnetic field distribution characteristics. The results show that high magnetic field,regional field, magnetic field gradient, and magnetic force formed by the different sections of the assembled magnetic medium in the same background magnetic field reduce in turn based on the triangle,square, hexagonal, octagon, dodecagon, and round. Based on the magnetic field characteristics analytic results, the magnetic separation tests of the ilmenite are carried out. The results indicate that the section shape of the toothed plate compared with the section shape of cylinder can improve the recovery of ilmenite up to 45% in the same magnetizing current condition of 2A, which is consistent with magnetic field characteristics analysis of different assembled magnetic medium section shapes.

Removing Iron by Magnetic Separation from a Potash Feldspar Ore

A new permanent magnetic separator was introduced to treat the ores with the characteristics of weak magnetic iron minerals and in a fine size range. The new machine was applied to the iron removal from potash feldspar. The effects of the magnetic field intensity, pulp density and grinding fineness on the iron removal were investigated. The optimized operation parameters were achieved and listed as follows： the -0.074 mm content is 85%, the pulp density is 45% and the magnetic field strength is 2T. A close test of middles regrinding was also carried out to improve concentrate yield. The data show that the grade of TFe（total iron） in potash feldspar product decreased from 1.31% to 0.21% and the concentrate yield reached 85.32%. All the results indicated that the traditonal high-intensity electromagnetic separators can be betterly substituted by the new permanent magnetic separator. This study may provide the theoretical evidence for iron removal from potash feldspar.

南芬选矿厂北山矿石选矿工艺试验

为配合南芬铁矿绿色矿山选矿提效及高效利用北山原矿石,在工艺矿物学研究的基础上,对北山矿石进行了选矿工艺流程试验。试验结果表明:采用辊磨前干抛—高压辊磨—辊磨产品湿式抛尾—阶段磨矿—弱磁选工艺,干抛和湿抛可提前抛除合计产率23.26%的尾矿,大幅降低了后续入磨矿量,提升了入磨矿样铁品位,最终获得的铁精矿产率为30.77%,TFe和mFe含量分别为68.17%和60.22%,TFe和mFe回收率分别为66.63%和98.16%。

缅甸某低品位复杂难选铁锡矿石综合回收试验研究

缅甸某低品位铁锡矿石含铁29.79%、锡0.495%,脉石成分主要为Si O_(2),主要有价矿物为磁铁矿和锡石,二者紧密共生,粒度较细。为确定该矿石的高效开发利用工艺,基于原矿性质研究,采用湿式弱磁选铁—锡石回收(摇床重选—摇床中矿再磨后高梯度强磁选除铁—摇床重选)—锡综合粗精矿浮选脱硫磁选除铁(弱磁选+高梯度强磁选)流程进行了选矿试验。结果表明:该工艺最终可获得锡品位57.956%、锡回收率69.08%的锡精矿,铁品位65.21%、铁回收率48.22%的铁精矿,硫品位46.35%、硫回收率38.31%的硫精矿,铁、锡和硫精矿所含杂质均未超标,总尾矿的锡品位降至0.153%,实现了铁锡矿石资源的综合回收利用。

某冶金级萤石精矿提质降杂试验研究

针对某CaF_(2)品位70.34%的冶金级萤石精矿进行了提质降杂试验研究。结果表明,采用“强磁选降硅-非磁性产品浮选降钙”工艺,实验室全流程试验获得了精矿产率58.30%、CaF2品位91.95%、回收率76.52%的萤石产品,萤石产品质量达到了制备无水氢氟酸的原料要求。

黄沙坪多金属矿强磁选抛废-强化锡石富集试验研究

为了实现黄沙坪多金属矿中低品位伴生锡石的资源化利用,开展了高梯度磁选抛废试验和浮选试验,开发了高梯度强磁选抛废-强化钨锡浮选富集的选矿新工艺。通过高梯度磁选预先抛废,钼、钨、萤石抛废损失率均低于10%,锡石显著富集于强磁选粗精矿中;使用Pb-BHA-SPA多配体金属基捕收剂对强磁选粗精矿进行再磨后精选,可得到WO_(3)和SnO_(2)品位分别为0.627%和0.78%、对应回收率分别为26.56%和18.03%的钨锡混合精矿。该工艺为低品位伴生锡石的强化富集和高效利用提供了新思路和新方法。

袁家村微细粒难选磁赤混合铁矿石提铁降硅试验研究

袁家村铁矿选矿厂原生产工艺流程获得的铁精矿TFe品位仅65%左右、SiO_(2)含量达4%~5%,难以满足市场对高品质铁精矿的需求。为此,在详细分析生产流程中混合磁选精矿性质的基础上,采用卧式搅拌磨机细磨—弱磁选+强磁选—反浮选工艺流程开展了提铁降硅试验研究。对TFe品位42.44%、SiO_(2)含量35.42%的混合磁选精矿,在磨矿细度为-0.045 mm占97%情况下,全流程试验获得了产率53.87%、TFe品位67.87%、SiO_(2)含量1.96%、TFe回收率86.15%的高品质铁精矿;磨矿细度为-0.045 mm占94%情况下,适当增大捕收剂RA用量,可获得产率54.76%、TFe品位67.14%、SiO_(2)含量2.09%、TFe回收率86.63%的高品质铁精矿。研究结果可作为选矿厂提铁降硅工艺流程优化决策依据,对类似性质难选铁矿石的高效开发利用具有参考价值。

某氰化尾渣中磁选回收铁试验研究

为综合回收利用某含金银多金属氧化矿氰化尾渣中的铁,针对氰化尾渣进行了弱磁选和强磁选回收铁的试验研究。试验结果表明:在弱磁粗选磁场强度为238.85 kA/m,弱磁精选磁场强度为159.24 kA/m,弱磁粗选尾矿强磁选磁感应强度为1200 mT的条件下,通过弱磁—强磁分选工艺,获得了全铁品位为64.08%、铁回收率为21.11%的弱磁铁精矿和全铁品位为45.81%、铁回收率为40.31%的强磁铁精矿,综合全铁回收率为61.42%,达到了综合回收利用铁资源的目的。

攀枝花某含钛铁尾矿工艺矿物学及钛回收工艺探索

由于攀枝花某钛铁矿石中钛、铁矿物致密共生,嵌布粒度细,造成选铁尾矿中钛的损失严重。为回收选铁尾矿中的钛资源,对含钛铁尾矿进行工艺矿物学研究。结果表明:矿石中钛、铁品位分别为6.25%和11.84%。钛物相主要为钛铁矿,其占比为59.38%,榍石和硅酸盐矿物中赋存的钛多达29.39%。钛铁矿集合体的嵌布粒度为0.016~0.032mm。在此基础上,开展钛回收工艺探索试验,结果表明:强磁选-浮选组合流程效果较好。在磨矿细度为-0.048mm占比为85%、磁感应强度为1.2T的条件下,经过“一粗一扫三精”的开路浮选,可获得TiO2品位46.56%,作业回收率42.71%的分选指标。

强磁—浮选工艺回收攀西某选钛尾矿中钛铁矿试验

为了回收攀西某钒钛磁铁矿选钛尾矿中钛铁矿,在试样化学成分分析、粒度分析的基础上,采用强磁抛尾—分级磨矿除铁—除铁尾矿强磁精选—浮选精选工艺,获得了产率4.13%、TiO_(2)品位47.15%,回收率30.71%的钛精矿。通过强磁选和浮选的联合使用,可以实现对选钛尾矿中钛铁矿的高效回收,不仅提高了钛铁矿的回收率,而且提高了资源综合利用率,对于钛资源的可持续利用具有重要意义,研究结果可为类似选钛尾矿的回收利用提供参考。

一种新型立环高梯度磁选机的研制

为解决现有立环高梯度磁选机磁场分布不均匀及中矿端磁感应强度低的问题,研发了一种新型立环高梯度磁选机。新型立环高梯度磁选机通过在第一磁系的中矿端一侧增加第二磁系与线圈,在中矿端弧形区域产生强磁场,磁感应强度保持与主分选区接近,解决了中矿端磁感应强度出现急剧衰减的问题,磁性颗粒可牢固吸附在磁介质表面,不会返回尾矿,不影响分选指标;该新型立环高梯度磁选机具有磁场均匀、富集比大、选矿效率高、处理量大、选矿成本低的优点,对于微细粒级弱磁性铁矿物,可获得更好的分选指标,市场应用前景广阔。

某闲置选矿系统处理某粉状赤铁矿石的可行性研究

毛里塔尼亚粉状(+5.0 mm 22.10%)酸性铁矿石铁品位58.65%,硫、磷含量极低,主要杂质成分为硅,铁在各粒级没有明显的富集现象。为确定该矿石的选矿工艺,进行了实验室试验和工业生产试验。结果表明,在磨矿细度-0.074 mm68.75%、强磁选磁感应强度为1.0 T的条件下,可获得铁品位64.09%、铁回收率92.18%的铁精矿;采用闭路磨矿—弱磁选—2次强磁粗选流程进行工业生产试验,可获得产率85.10%、铁品位63.54%、铁回收率92.68%的总精矿,铁品位28.68%的尾矿可作为铁质校正原料销售至周边水泥厂,实现资源的综合利用。

某含铁铜尾矿回收微细粒弱磁性铁试验研究

某铜尾矿中含铁29.38%,经工艺矿物学研究发现,这些铁主要赋存在赤铁矿和褐铁矿中,它们粒度细小,磁性较弱,且部分铁矿物嵌布关系复杂。为了经济有效地回收这些铁矿物,并针对该类含铁矿物回收过程中存在的回收率低、精矿品位低的难题,进行了选矿试验研究。试验结果表明:在粗选磁感应强度为1.6 T,粗精矿磨矿细度为-0.074 mm78%,精选磁感应强度为1.0 T的条件下,采用强磁粗选—粗精矿再磨再选工艺流程,可获得铁品位为60.01%,铁回收率为36.10%的铁精矿,实现了该尾矿的资源化再利用。

鞍千选矿厂强磁选精矿正浮选试验研究

鞍千选矿厂为提高浮选指标,对强磁选精矿进行了正浮选试验,研究了pH值、捕收剂TD-Ⅱ用量、浮选机转速和浮选温度对浮选指标的影响,并对赤铁矿和石英单矿物进行了接触角测试。试验结果表明:铁品位21.42%的原矿在pH值为6.0、TD-Ⅱ用量900 g/t、浮选机转速2000 r/min、浮选温度35℃的条件下,经1粗1精2扫闭路试验,可获得精矿产率41.38%、铁品位43.54%、铁回收率84.11%的铁精矿;捕收剂TD-Ⅱ可显著提高赤铁矿的接触角,并且不改变石英的接触角,捕收剂TD-Ⅱ对赤铁矿具有较好的选择性,该研究结果可为该选厂的浮选指标优化提供依据。

国外某高磷鲕状铁矿选矿试验研究

国外某高磷鲕状铁矿石主要铁矿物为磁铁矿和赤褐铁矿,有害杂质硫含量较低,伴生杂质硅、铝、磷含量较高。为降低该高磷鲕状铁矿石中的磷矿物含量,提前抛出部分含磷高的尾矿,进行了多粒级干式预选试验研究,探索预选抛废的可行性,同时对磨选工艺进行了阶段磨矿磨矿细度试验。试验确定了原矿阶段磨矿—弱磁选流程,最终获得了产率47.42%、铁品位64.45%、磷品位0.501%、铁回收率53.19%的铁精矿,有效降低了铁精矿中的磷含量,为合理开发利用该铁矿资源提供了参考依据。

攀西某钒钛磁铁矿重选尾矿再回收试验

攀西某超低品位钒钛磁铁矿为了回收利用总尾矿中的钛资源,在尾矿性质研究的基础上,进行了重选尾矿再回收试验。试验结果表明:尾矿通过强磁选—分级—弱磁选工艺,可得到全铁品位为19.07%、TiO_(2)品位为18.25%的入浮矿样;对入浮矿样开展脱硫—1粗3精开路浮选,可得到TiO_(2)品位47.27%、TiO_(2)回收率70.78%的合格钛精矿,同时分级后的粗粒级矿物通过重选工艺,在摇床床面精矿与尾矿的截取比例为2∶8的条件下,可获得精矿产率为6.46%、全铁品位为13.41%、TiO2品位为8.83%的钛原料,能够并入主系统对其中的钛金属进行再次选别回收,以获得更高的钛资源综合利用率。

南芬选矿厂选别工艺流程试验

为支撑南芬选矿厂智能提效大型化改造,以主采场矿石为研究对象,在工艺矿物学研究的基础上,采用辊磨前干抛—高压辊磨—辊磨产品湿式抛尾—阶段磨矿—弱磁选组合工艺流程,可提前抛除产率21.40%的尾矿,大幅降低后续入磨矿量,提升入磨矿样全铁品位,最终获得产率39.07%,TFe和mFe含量分别为68.20%和66.19%,TFe和mFe回收率分别为86.66%和98.98%的铁精矿。

强磁选—磁化焙烧—弱磁选工艺回收某尾矿中的菱铁矿

云南某尾矿含铁13.88%,主要以菱铁矿的形式存在,具有回收利用价值。采用“强磁选—流态化磁化焙烧—弱磁选”工艺回收铁,考察了矿样焙烧前后铁物相的转变。结果表明,强磁选可以获得产率21.60%、铁品位27.18%、铁作业回收率40.19%的铁粗精矿;铁粗精矿采用550℃预氧化7.5 min并在温度450℃、还原势R=0.6条件下还原磁化焙烧7.5 min,能保持还原产物中Fe_(3)O_(4)的稳定性,无FeO生成,保证了铁氧化物的高磁性转化率和强适应性,获得产率90.84%、铁品位30.02%的焙砂;焙砂经弱磁选可获得产率35.29%、铁品位60.51%、作业铁回收率71.13%的磁铁精矿。研究成果为尾矿资源综合利用及难处理铁矿资源高效利用提供了有益参考。

某难选高硫铁矿选矿试验研究

为更好地回收某难选高硫铁矿,对含铁30.49%、含硫2.35%的原矿,利用化学多元素分析、光学显微镜、矿物自动分析仪(MLA)等手段,对矿石的矿物组成、主要元素赋存状态、主要矿物的嵌布特征等进行了研究,并进行了选矿试验。结果表明:(1)磁铁矿矿物粒度总体较为细小,部分磁铁矿与黄铁矿、磁黄铁矿紧密嵌布;(2)采用“弱磁-铁粗精矿脱硫-再磨-弱磁”工艺,在一段磨矿细度为-0.074 mm占80%,二段磨矿细度-0.038 mm占95%条件下,可获得铁精矿含TFe 63.35%,含S 0.21%,铁回收率69.66%的指标。