马钢桃冲选厂二段中磁改造及工艺参数优化

分析了桃冲选厂流程特点和二段扫选中磁机参数存在的缺陷,通过采用改进磁系特性、提高分选区平均场强、调整分选时间等措施,使选矿回收率和选别效率有了较大的提高。      

永磁带式高梯度磁选机的研制

研制了一种中等场强的永磁带式高梯度磁选机。无端的高梯度介质带在分选空间循环通过，从而实现了非磁性物与磁性物的不断分离。在试验研究的基础上提出了合适的操作参数。磁系由Ｎｄ－Ｆｅ－Ｂ永磁体构成，其磁能积为２５５ＫＪ／ｍ３，剩余磁感为１．１Ｔ。采用磁铠装磁路结构使磁体设计最佳化，在永磁磁路定律的基础上，导出了计算磁场强度的简单方程。工业试验结果表明，带式永磁高梯度磁选机的分选行为与电磁高梯度磁选机的分选行为相似。     

脉动高梯度磁选分离难选铜钼混合精矿的研究

脉动高梯度磁选法是８０年代初发展起来的一种分离细粒弱磁性成分的有效方法，它能有效地提高磁性产品的质量，防止介质堵塞。我们首次将这一磁选新技术用于分离细粒难选铜钼混合精矿。试验结果表明，它可预先分离产率７０％以上的低钼高品位铜精矿，使钼在非磁性产品中得到相应的富集，大大减少后续精选作业的矿量，降低药剂耗量和生产成本，大幅度提高经济效益．     

Slice matrix analysis for combinatorial optimization of rod matrix in PHGMS

Rod matrix is effectively applied in pulsating high gradient magnetic separation (PHGMS), due to its reliable operation, simple combination and resistance to mechanical entrainment. The matrix is made of huge numbers of rod elements and as a whole its configuration presents a decisive role in the operation of PHGMS, due to the fact that it has an inherent determination on the distribution of magnetic field in the matrix and on the collision efficiency of particles with the matrix, thus producing a dominant control on the dynamics of magnetic particles in the matrix and on the separation performance of PHGMS. An experimental approach entitled Slice Matrix Analysis (SMA) method is developed and attempted to optimize the configuration of rod matrix, with a cyclic pilot-scale PHGMS separator in concentrating fine hematite. It was found that the configuration has a significant effect on the separation performance of PHGMS, and the SMA method provides an effective way for the optimization of rod matrix.     

A realistic description of influence of the magnetic field strength on high gradient magnetic separation

The magnetic field strength is a very important parameter in high gradient magnetic separation (HGMS). It was usually thought that the increase of magnetic field strength will lead to the decrease of the minerals’ susceptibility and the matrices’ surface area available for the buildup of the magnetic particles, which was responsible for the decrease of the mineral recovery in high magnetic field. But the detailed influence of the magnetic field strength on the behavior of the particles of different characteristics in HGMS is still not clear. A very important factor was usually ignored in the process of HGMS, namely the behavior of the low grade intergrowths. In this article, the influence of magnetic field strength on the behavior of the magnetic monomers and intergrowths in HGMS was investigated with the particle buildup model and the particle capture model. The buildup profile of the magnetic monomers increases with the increase of the magnetic field strength despite the decrease of the minerals’ susceptibility. The low grade intergrowths can hardly accumulate on the matrices in a low magnetic field but can largely accumulate on the matrices in a high magnetic field. In a high magnetic field, there exists the competitive accumulation between the low grade intergrowths and the fine monomers. Coarse intergrowths may have larger buildup profile and shorter capture time than the fine monomers and will accumulate preferentially on the matrices. In some circumstances, the competitive accumulation of the particles will lead to the decrease of the recovery in a high magnetic field. A moderate high magnetic field can ensure a high recovery. For a magnetic product of high grade and recovery, high monomer dissociation degree is necessary and the over grinding of the minerals should be avoided, and classifying the minerals to handle the coarse fraction and the fine fraction separately can also be considered.     

Effect of magnetic field orientation on high gradient magnetic separation performance

The magnet has a dominant role in a high gradient magnetic separator; it provides the passage for the magnetic field and the working space where the matrix is placed to produce magnetic gradients and magnetic forces high enough to capture magnetic particles from the slurry. The effect of the magnetic field orientation of the magnet on high gradient magnetic separation (HGMS) performance has been comparatively investigated on a pilot pulsating HGMS separator with vertical and horizontal magnets respectively. The results of the investigation indicate that the magnetic field orientation has a significant effect on the performance. It was concluded that a properly designed magnet in a HGMS separator greatly improves the performance.     

SSS-III系列水平磁场立环脉动高梯度磁选机的研制与应用

SSS-II系列水平磁场立环脉动高梯度磁选机虽具有精矿品位高、磁介质不易堵塞、磁系无腐蚀的优点,但磁能利用率不足、磁介质体积量较小、回收率偏低等问题制约了其推广应用。为解决这些问题,以SSS-II系列磁选机为基础,开发了SSS-III系列水平磁场立环脉动高梯度磁选机。该磁选机的双层磁介质盒分选环结构,显著提高磁能利用率、磁介质体积量和分选作用高度,实现强弱磁性颗粒的梯级分选,起到“1粗1扫”短流程选别效果,提升设备处理能力和选矿回收率;双层冲洗卸矿装置确保磁介质不易堵塞的优点得以延续。攀枝花某选钛厂粗选车间的生产实践表明,SSS-III-2750型水平磁场立环脉动高梯度磁选机运行平稳、可靠,在原矿TiO₂品位为9.89%条件下,获得了TiO₂品位为17.54%、TiO₂回收率为86.23%的钛粗精矿,与SSS-II-2750型水平磁场立环脉动高梯度磁选机相比,在精矿TiO₂品位低1.09个百分点的情况下,TiO₂回收率提高了11.91个百分点,与现场某垂直磁场立环脉动高梯度磁选机相比,在原矿TiO₂品位仅高0.43个百分点的情况下,精矿TiO₂品位和回收率分别大幅度提高了3.42和15.56个百分点。     

中磁机在桃冲选矿厂的应用探讨

桃部选矿厂采用摇床辊弱磁尾矿，因摇床操作因素复杂，适应性较差，致使金属回止率较低。试验研究表明：采用磁机辊该部分尾矿，选别效率高于强磁－遥床或者摇床单独选别，说明中磁机取代摇术选别弱磁尾矿是可行的。     

棒介质排列组合对高梯度磁选指标的影响研究

脉动高梯度磁选是微细粒弱磁性矿物的高效选矿技术,通过用微细粒赤铁矿进行脉动高梯度磁选试验,研究棒介质排列组合对高梯度磁选指标的影响。试验发现,棒介质排列组合对高梯度磁选指标具有明显影响,交叉排列优于矩形排列,可以获得更高的精矿品位、铁回收率和分选效率;随介质丝间距的增大和介质丝层数的减小,介质丝对磁性矿物的捕获能力降低,导致尾矿铁品位上升,分选效率下降,而精矿品位变化不明显。可以得出结论,棒介质排列组合优化,可以明显提升高梯度磁选的效能。     

湿式高梯度磁分离工业装置的优化实验方法

工业磁分离机在投入正式运行之前 ,需要从质和量两方面对可能的影响因素进行研究。本文提出了湿式磁分离工业装置的一种工业实验方法。在分析磁分离机工作过程的基础上 ,可推导出处理量与相关参量之间的函数关系。通过一系列的分选实验 ,又可得到分选效果 (质量 )与这些参量之间的关系。在确定了产品质量的基础上 ,我们即可以实验结果对照相同参量下的处理量计算值 ,最终寻找出满足质量标准并产生最大处理量的参量集合     

干式永磁高梯度磁选机的研制

随着非金属矿业的发展，为了解决微细物料的干法除铁，开发了一种新型干式永磁高梯度磁选机。该机采用稀土永磁多极波状磁场磁铁铠装磁系，内外磁系间距可调以适应不同分选工艺对分选场强的要求。采用轴向振动系统可以选择性捕获颗粒，防止磁介质的机械阻塞。磁选机易于封闭，有利于风送物料，减少粉尘对空气的污染。工业试验表明：经过干式永磁高梯度磁选机处理后，连州钾长石粉料中的Ｆｅ２Ｏ３从０．２７％降至０．１８％，达到了工业生产的要求。     

用振动高梯度磁选精选界牌高岭土的研究

本文详细研究了各种因素对湖南界牌高岭土（Fe2O3＋TiO2＞0．85％）高梯度磁选除铁、钛效果的影响。试验表明，界牌高岭土经一次高梯度磁选，可获得产率大于85％，Fe2O3＋TiO2小于0．5％的一级产品，白度可从入选前的61．3％提高到70．3％；该产品经进一步精选，Fe2O3＋TiO2可降到0．4％以下。     

微细磁铁矿选矿尾矿中回收赤铁矿的工艺研究

采用高梯度磁选和离心机重选回收磁铁矿选矿尾矿中的赤铁矿。结果表明, 当磁场强度为800 kA/m、磁介质为Φ2 mm棒介质、脉动冲次为200 r/min时, 一次磁选精矿品位为31.2%, 精矿回收率为84.44%; 将一次磁选精矿细磨至-0.045 mm粒级占90%, 采用高梯度磁选-离心机重选工艺, 当离心机转鼓转速为400 r/min、补加水量为2000 L/min时, 最终铁精矿品位为60.07%, 回收率为43.89%。     

新型开放磁系永磁筒式强磁选机的研制与应用

以COMSOL仿真优化了开放磁系磁场力HgradH模型,设计了基于开放磁系小极面排斥磁极布置的强磁磁路结构,使筒表分选区磁场强度可达到800 mT以上,试验结果表明,与常规开放磁系永磁筒式磁选机相比,新型开放磁系永磁筒式强磁选机分选某细粒铬铁矿、钛铁矿,回收率分别提高了34.11%、16.99%,说明该新型磁选机更有利于细粒弱磁性矿物的回收。      

SSS-Ⅱ型高梯度磁选机在承德钛铁矿生产中的应用

SSS-Ⅱ型系列湿式双频双立环高梯度磁选机是新产品,由于采用水气联合卸矿,双脉动、多梯度磁介质和矩阵式排布的高富集率,因此具有分选精度高、适用性广等优点。通过在承德钛铁矿生产的应用表明,SSS-Ⅱ型高梯度磁选机作为钛粗选设备,在原矿品位变化较大的情况下,具有较稳定的选别指标和低廉的运行成本。     

应用SLon立环脉动高梯度磁选机提高选矿效率

介绍了Slon立环脉动高梯度磁选机的研制进展、主要特点及其应用案例。SLon磁选机在辽宁宝国铁矿用于分选磁铁矿、赤铁矿和菱铁矿的混合矿, 成功实现了0~3 mm脉石提前抛尾, 减少后续磨矿费用30%, 全流程选矿回收率提高约9个百分点; SLon磁选机在重钢西昌矿业有限公司用于分选钛铁矿, 钛铁矿回收率从10%左右提高到50%。应用实践表明, SLon磁选机能显著提高选矿效率和降低选矿成本。     

Study on capture radius and efficiency of fine weakly magnetic minerals in high gradient magnetic field

The recovery of ultrafine weakly magnetic minerals using HGMS is proved a tough issue in industrial practice. Optimization of HGMS parameters determines the recovery result. The capture limits of weakly magnetic particles of diameter range 1–30 μm in high gradient magnetic field are studied using a numerical computation method. The matrix size and slurry velocity as well as the magnetic induction show great influence on the capture radius. The capture radius decreases rapidly with the decrease of particle size, the increase of matrices diameter and slurry velocity. For generalized condition, the capture radius is largely dependent on the ratio of slurry velocity V₀ to the so called magnetic velocity V_m. The capture efficiency decreases with the increase of the matrices arrangement value of d/a (the ratio of half the spacing between matrices to the matrix radius). The relationship between capture efficiency and V₀/V_m as well as d/a is obtained. This relationship can provide a guidance of choosing matrices of the perfect size and arrangements or configuring the HGMS system to work with high capture efficiency. It is also demonstrated how to regulate the HGMS system from a working point of low capture efficiency to a working point of high capture efficiency.     

边界单元法在高梯度磁选机中的应用：鞍形磁系磁感应强度的计算

将边界单元法应用于高梯度磁选领域，获得了高梯度磁选机中鞍形磁系磁感应强度的数值计算方法，论述了它的程序实现过程和处理技巧，通过实例计算并与实测值比较，结果表明该方法简单易行，精度较高，可供实际应用     

钽铌粗精矿高梯度磁选数值法分析

以某富铪锆矿粗精矿为研究对象,在进行高梯度磁选钽铌试验的同时,采用数值解析方法分析高梯度设备内的磁场特性,将磁场划分为六边形单元并用"瞬时快照法"对磁选过程进行分析,用两组偏心椭圆来近似表示不同矿粒在磁场中的捕集区域,通过求解偏心椭圆在x轴上的临界值来确定钽铌精矿的产率、回收率及品位。数值法计算结果和高梯度磁选试验结果的对比分析表明:数值计算结果揭示了高梯度磁选的捕集规律,能够实现高梯度磁选试验的条件参数对分选效率影响的预评估,在缩小试验范围、降低试验次数的同时能够实现分选效率的提高。该研究方法及结果对钽铌矿及其它弱磁性矿物的高梯度磁选实践具有一定的指导意义和参考价值。      

酒钢粉矿复合团聚磁种磁化磁选试验研究

为高效选别酒钢粉矿,进行了复合团聚磁种磁化磁选试验研究。结果表明,酒钢粉矿在磨矿细度-74 μm粒级占87.54%、中强磁磁场强度480 kA/m预选后,预选尾矿在六偏磷酸钠浓度100 mg/L、油酸钠浓度80 mg/L、磁种用量3%条件下复合团聚磁种磁化后,在磁场强度320 kA/m下磁选,可获得TFe品位47.27%、回收率77.15%的合格铁精矿,有效实现了酒钢粉矿中含铁矿物的回收。