某铁矿强磁尾矿反浮选回收试验研究

针对我国西部某铁矿强磁选尾矿进行了反浮选回收铁资源的试验研究, 探讨了pH值、抑制剂可溶性淀粉用量、阳离子捕收剂十二胺用量对浮选指标的影响。结果表明, 在矿浆pH=10、可溶性淀粉用量2 400 g/t、十二胺用量400 g/t条件下进行一粗一精(精选药剂用量减半)闭路反浮选, 可获得铁品位43.88%、回收率50.93%的铁精矿产品。     

In-situ elongated aluminium borate grains toughening WC- 1.87 wt % Al2O3- 4.13 wt % ZrO2 composite via spark plasma sintering

In this work, a novel way was developed to facilitate the sintering of a binderless cemented carbide with Al₂O₃ contain while improving its toughness. WC- 1.87 wt % Al₂O₃- 4.13 wt %ZrO₂ cemented carbides with 1 wt % B₂O₃ as additives were consolidated by high energy ball-milling and spark plasma sintering the as-milled composite powders. The effects of 1 wt % B₂O₃ content on the sintering behaviour, microstructure and mechanical properties of the obtained cemented carbides were investigated. The presence of B₂O₃ significantly lowers the sintering temperature by forming liquid phase and react with Al₂O₃ which contributed to obtaining fully dense specimens at 1350 °C and maintains fine grain sizes of WC until the temperature exceeding 1450 °C. The sintering temperature of the specimens with optimum mechanical properties has been also reduced comparing that of the original WC- 1.87 wt % Al₂O₃- 4.13 wt %ZrO₂ cemented carbides. Furthermore, the addition of B₂O₃ triggered the reaction between B₂O₃ and Al₂O₃ resulting in forming in-situ elongated aluminium borate grains (A₄B₂O₉ and A₁₈B₄O₃₃ whiskers), which promoted the toughness. The specimens sintered at 1450 °C exhibited optimal mechanical properties: the Vickers hardness and fracture toughness were 19.26 GPa and 11.49 MPa m^1/2, respectively.     

Ceramics composites from iron ore tailings and blast furnace slag

The search for materials and methods capable of reducing human impacts on the environment is of utmost importance nowadays. This study's primary purpose was to analyze the technical feasibility of ceramic composites production utilizing Fundão Dam's Iron Ore Tailings (IOT), Blast Furnace Slag (BFS) from charcoal, and Foundry Sand (FS) as partial substitutes for the traditional raw materials – sand and clay – for application in building industry materials. The composites were molded in rectangular specimens and fired at temperatures of 900, 950, 1000, 1050, and 1200 °C. The developed materials were analyzed and characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Thermogravimetry (TGA), and Differential Thermal Analysis (DTA). The obtained materials had flexural strength modulus of up to 12.19 MPa, water absorption ranging from 2 to 22%, linear shrinkage ranging from 0.02 to 6.50%, and apparent density ranging from 2.03 to 1.63 g/cm³. The study of the internal structure formation process revealed the formation of amorphous structures in the composites. The results demonstrated that these waste materials may be jointly used in construction materials, contributing to the reduction of natural resource extraction, besides enabling their correct disposal, minimizing environmental impacts, and improving the life quality of the surrounding communities.     

铅锌尾矿配料对水泥熟料易烧性影响的研究

在相同的熟料设计率值、相同的烧成制度下,对不掺加和掺加铅锌尾矿的生料分别进行了生料易烧性的对比实验。研究结果表明:铅锌尾矿可以部分替代铁矿石进行配料生产硅酸盐水泥熟料并起到矿化作用,能够显著改善生料易烧性。     

某矿山充填料浆坍落度试验研究

充填采矿成为了目前的发展趋势,充填料浆的流动性在此过程中的作用不容小觑。对某矿山的料浆流动性进行坍落度试验研究。结果表明,塌落度随着充填料浆的灰砂比和料浆浓度的变化而变化,当料浆的浓度小于74%时,坍落度大于22.5 cm,其流动性明显有所改观,此时可实现管道自流输送的目的。低浓度的充填料浆有较好的流动性,但该情况下的充填体强度不能得到很好的保障,通过观察充填料浆在不同灰砂比下不同浓度的坍落度以及摊开的样子得出,浓度在68%之上的料浆具有良好的保水性,不会有粒级不同的颗粒相互分离或析水的不良情况,因此把充填料浆的浓度初设为68%~74%。相应的坍落度为22.5cm,完全摊开。     

青海某金矿浮选尾矿工艺矿物学研究

青海某金矿石平均含金2.62 g/t、含砷0.28%,为典型的含砷难处理金矿。选矿厂采用"一次粗选、两次精选、两次扫选"浮选工艺,但金的回收率仅为77%左右,损失严重。为了查明金损失原因,提高选矿厂浮选回收率,利用化学多元素分析、光学显微镜、扫描电镜等工艺矿物学研究手段,对青海某金矿选矿厂浮选尾矿进行工艺矿物学研究。结果表明,浮选尾矿含金0.81 g/t,但金的赋存状态较为复杂,主要以极微细粒(粒度0.3~3μm)形式包裹于石英、方解石、钠长石等脉石矿物中,其次是以微细粒(粒度2~6μm)形式包裹于毒砂和斜方砷铁矿中,还可见部分金粒(粒度小于10μm)嵌布于脉石裂隙中。金嵌布粒度极细和包裹金所占比例较高,是选矿回收率不高的主要原因。     

含锡抑硫浮锌尾矿FS活化浮硫试验

云南某锡矿选矿厂采用抑硫浮锌-硫酸活化浮硫-浮硫尾矿选锡流程回收矿石中的主要有用元素锡、锌、硫。硫酸活化浮硫不仅腐蚀搅拌桶、浮选机等矿浆存储及输送设备，而且与矿物作用还会释放有毒的硫化氢气体，造成环境污染。为解决此问题，武汉理工大学相关课题组有针对性地研制出一种新型药剂FS，可替代硫酸活化现场被抑制的硫。试验对以FS为活化剂的脱硫工艺条件进行了研究。结果表明，硫、锡品位分别为21.24%、11.43%的试样，以FS+硫酸铜为活化剂，丁基黄药为捕收剂，2#油为起泡剂，经1粗1精1扫闭路流程处理，可获得硫品位为36.57%、含锡0.60%、硫回收率为97.76%的硫精矿，以及锡品位为25.66%、含硫1.10%、锡回收率为97.03%的脱硫产品，较好地实现了硫锡分离。新型药剂FS与硫酸铜的组合使用，不仅解决了设备的腐蚀问题，而且降低了药剂消耗，消除了硫化氢气体对环境的污染。     

基于宏微观耦合分析胶结充填体强度差异的研究

在高阶段采场充填过程中,井下原位取芯样品强度远远高于地表实验室试件。本文选取了李楼铁矿6个高阶段充填采场取芯样品,发现井下原位取芯强度比地表充填试件高1.59 MPa。通过电镜扫描和能谱分析,确定了胶结充填体内部的水化产物成分,进一步分析了全尾砂充填料浆固结演化过程。基于充填体的宏微观试验,对井下原位强度与地表试件的差异性进行耦合分析,揭示了自重压力对充填体的宏观力学性能和微观孔隙结构的作用机理。研究成果可为高阶段采场进一步降低灰砂比提供理论依据。     

攀西钒钛磁铁矿尾矿制备储水泡沫陶瓷的研究

以攀西钒钛磁铁尾矿和废玻璃为主要原料通过高温烧结法制备储水泡沫陶瓷，研究原料配比和发泡剂（SiC）添加量对材料性能的影响。结果表明:随着钒钛磁铁矿尾矿含量的增加，材料的体积密度及抗压强度逐渐增大，平均气孔孔径逐渐减小；当尾矿添加量为50 wt%，材料的体积吸水率出现极值。当SiC添加量为0.3 wt%，材料内部气孔分布均匀，平均孔径约为2.93 mm。最终以50.0 wt%的钒钛磁铁矿尾矿和50.0 wt%的废玻璃为原料，外加3.0 wt%的石英，0.3 wt%的SiC，3.0 wt%的Na3PO4，在1040℃下制得性能最优的储水泡沫陶瓷，材料的体积密度为0.26 g/cm-3、体积吸水率为56.5%和抗压强度为0.68 MPa。采用SEM、XRD等检测手段研究材料的微观形貌及物相组成，结果表明储水泡沫陶瓷内部由三维立体结构组成，有利于储存水分；材料主要物相包括硅灰石、长石、透辉石和钛铁矿。      

基于P波模量的原位胶结充填体强度预测模型研究

原位胶结充填体质量评价通常采用单轴抗压强度作为表征指标,由于在现场工程中无法快速、准确获取充填体的强度值,因此需要建立一种参数易于获取且准确的原位胶结充填体强度预测模型。基于胶结充填体物理力学参数的内在联系,从量纲平衡的角度探索了胶结充填体单轴抗压强度与P波模量的关系。根据C矿和I矿两种原位胶结充填体的密度、P波速度及取芯强度的测试数据,采用线性拟合的方法获得了基于P波模量的原位胶结充填体强度预测模型。通过对C矿和I矿的强度预测模型拟合效果分析可知,P波模量与取芯强度呈正相关性,且拟合效果较好,证明原位胶结充填体强度预测模型精度高,具有很强的实用性。