立磨机磨矿原理的探讨

影响立磨机磨矿效果的主要因素有螺旋直径、螺距、转速和介质层高度。通过试验和理论分析, 对立磨机的磨矿原理进行了探讨, 指出在磨矿介质形成的一定压力下, 物料的粉碎主要是通过磨矿介质的研磨作用实现的。     

立磨机的研究及应用

本文所述之立磨机以表面磨剥作用为主,适于各类矿石的细磨和超细磨,其电耗比普通球磨机低50%以上,且产出物料可自然分级,能保持晶体原有形状.文中述及立磨机的工作原理、结构特点、磨矿介质的特性及其在金属和非金属矿工业中的应用。     

立磨机磨矿机理研究

本文分析了立磨机内磨矿介质的运动状态,分别讨论了磨矿介质在两个磨矿区域产生的不同磨剥作用,分析结果表明增大螺旋叶片直径和转速,减小螺旋升角有助于提高立磨机磨矿效率,但是为了能使立磨机磨矿效率最大化的同时降低磨矿能耗,必须综合考虑各种磨矿因素才能确定合理的结构参数和运行参数。     

立磨机细磨重质碳酸钙的试验研究

立磨机可成功地用于磨制超细重质碳酸钙，影响其工作的主要因素的转速，浓度，介质量，介质种类及助磨剂等，立磨机效率高，能耗低。     

VTM立磨机在庙沟铁矿细磨工艺中的应用研究

针对庙沟铁矿有用矿物嵌布粒度为0.04~0.07mm,现有细磨工艺很难达到90%的单体解离,而且处理能力不足的问题,对庙沟铁矿粗精矿进行了细磨工艺试验研究。最终确定前两段磨矿工艺不变,用一台VTM1500立磨机代替原有的两台MQY2736球磨机作为第三段磨矿工艺,结果提高磨矿产品细度44.49%,单体解离从87.6%提高到96.7%。该矿使用立磨机的同时对工艺流程进行了相应优化,解决了原流程循环量大的问题,磨机台时能力提高到8.3t/h。工业应用表明最终铁精矿品位由原来的65.2%提高到66%以上,年增经济效益3024.05万元。     

VTM 1500立磨机在某铁矿选矿工艺中的应用

某铁矿由于矿石性质的变化,原磨矿细度难以获得理想的分选指标。为此开展了立磨机替代球磨机进行第三段磨矿的试验。研究表明,采用3台VTM 1500立磨机替换原2台MQY4.8 m×7.0 m球磨机,较好地解决了矿石单体解离度不足的问题;在精矿品位相当的情况下,精矿产率提高了4.92个百分点,回收率提高了7.64百分点,每年增加经济效益7 261.58万元。     

KLM型立磨机在金属矿中的应用

介绍了立磨机的基本结构和工作原理,重点阐述了KLM型立磨机在金属矿中的应用情况,KLM型立磨机用于金属矿的细磨或再磨作业中,可以经济地提高矿物单体解离度,促使目的矿物解离更加充分、裸露更多新鲜表面,对有效提升目的矿物品位、改善精矿品质,降低选厂生产成本具有重要作用。工业实践表明,KLM型立磨机是一种适合于金属矿细磨与再磨作业,节能高效的磨矿设备。     

立式搅拌磨机的研究与应用进展

介绍立式搅拌磨机的结构、工作原理、研究新方向及立式搅拌磨机的工业应用实例。     

基于立盘式搅拌磨机的铁氧体磁粉超细磨影响规律研究

为了研究验证立盘式搅拌磨机对铁氧体磁粉超细磨效果的影响规律,基于试验室立盘式搅拌磨机试验平台进行正交试验,进行了搅拌盘直径、相邻搅拌盘间隙、空隙盘面积比、搅拌盘边缘线速度、搅拌盘数量5个关键参数对磨矿效果的影响规律研究。研究结果表明：以能耗作为考核指标,影响作用从大到小依次为搅拌盘转动速度、搅拌盘数量、搅拌盘直径、相邻搅拌盘间隙和空隙盘面积比;试验对比了北矿科技阜阳生产基地铁氧体磁粉的超细磨过程,使用立盘式搅拌磨机为超细磨设备,可降低吨能耗22.5%。     

几种典型搅拌磨机在金属矿山的应用进展

搅拌磨机是近年来金属矿细磨和再磨作业的重要装备,具有高能量输入密度、高效率、高强度等特点,解决了细粒嵌布难分选的难题,典型的金属矿细磨搅拌磨机有Isa磨机、立式螺旋搅拌磨机(VTM)、SMD磨机。笔者介绍了几种典型搅拌磨机的研究现状和发展趋势、结构特点和工作原理、主要的应用进展等。     

塔磨机技术综述

塔磨机是一种新型湿式细磨和超细磨设备,该设备在选矿厂碎磨车间和烟气脱硫石灰石浆液制备等领域逐渐得以应用.本文主要介绍了国内外塔磨机的发展状况、粉磨机理、主要结构及各部件之间的装配关系,以及塔磨机常用的工艺位置、给料和排料颗粒粒度和工艺流程.     

The shape of product size distributions in stirred mills

This paper presents the results of an extensive laboratory and pilot stirred milling testwork program conducted using different types of mills, fed with different types of materials and operated at different conditions. The results indicate that the slope of the product size distribution (PSD) curve remains relatively unchanged in the coarse product size range but decreases in the fine product range (less than about 20 μm size), regardless of the type of stirred milling technology used for grinding. This work therefore confirms that a narrower product particle size distribution than the feed size can be achieved independent of the type of stirred milling technology used for fine grinding below 20 μm. The change in the PSD width in fine grinding is due to the change in the material breakage properties and a change in the mill operating conditions which affect the breakage process. In the normal operating range of grinding media size, the effect on the PSD shape is not significant.     

A multiscale method for including fine particle effects in DEM models of grinding mills

A multiscale model for including interstitial powder or fine particles in DEM simulations of grinding mills is proposed. This consists of a traditional DEM model at the macroscale which includes only grinding media and potential coarser fractions of feed and product. Microscale models are embedded within this macroscale model. These can be sufficiently small that the fine powder can be included in a computationally affordable manner. The direct inclusion of the fine particles in the model allows predictions to be made of the effect of the local grinding environment on these fine particles. A shear cell is a good choice for the microscale model as it can well represent the local flow conditions at different points within the mill macroscale model. Averaging the macroscale flow allows the local collisional environments to be characterised and provides estimates of the shear rate and normal stress at each of the microscale locations which then controls the configuration of each microscale shear cell. A 1-way coupled implementation of this multiscale model is demonstrated for a simple cement ball mill. The relative importance of each region of the flow is determined with the toe region being the dominant contributor to the grinding. The grinding action produced by the shearing of thin layers of powder between adjacent layers of media flowing over each other is clearly demonstrated by the behaviour predicted in the microscale models. Methods for calculating power draw that include the effect of powder and for constructing collision energy spectra for the powder are described. Finally, the importance of the cushioning effect of high powder loads on the flow behaviour of the media is demonstrated.     

Using DEM to compare the energy efficiency of pilot scale ball and tower mills

Tower mills are considered to be appreciably more energy efficient than ball mills. Why this should be so is a question which can be explored by using DEM to simulate one machine of each type with similar breakage capabilities. This paper reports on a comparison between a pilot scale tower mill and a small ball mill in terms of the power required to produce reasonably similar distributions of normal and tangential impacts. While the tower mill produces quite a narrow spectrum of normal energies, the ball mill produces a wide distribution. Hence, the ball mill can be expected to be much more “forgiving” of variable feed conditions but much less efficient in terms of utilization of the energy from media interactions.     

充填配比方案优化的正交试验研究

为解决国内某铜矿充填分级尾砂供应量不足,充填料浆离析严重,充填体强度低的问题,应用正交试验展开了充填配比方案优化研究,试验以充填料浆质量浓度、灰砂比和细砂含量作为影响因素,以试块28 d单轴抗压强度、充填料浆泌水率和充填料浆扩散度作为试验指标,运用极差和方差分析法分析影响因素对试验指标影响的敏感性和显著性。试验结果表明：影响试块强度敏感性最强的因素是灰砂比,影响料浆泌水率和料浆扩散度敏感性最强的因素都是浓度;灰砂比对试块强度影响显著,浓度和细砂含量都对料浆泌水率影响显著（其中浓度影响最显著）,浓度对料浆扩散度影响显著。最终推荐充填配比方案为充填料浆浓度70%~72%,灰砂比1∶6~1∶8,细砂含量15%~20%;最优充填配比方案为充填料浆浓度72%,灰砂比1∶6,细砂含量15%。     

锚杆支护参数的优化

以云南某铜锡矿为例,利用FLAC~(3D)模拟对巷道支护进行模拟,并用正交试验设计的方法对其巷道支护参数进行分析,然后结合悬吊理论分析,为矿山提供更好的锚杆支护参数。研究结果证明:在满足巷道稳定性要求的同时,也要选择经济可行的锚杆支护参数,当锚杆长度为2.1m,间距为0.8m,排距为1.0m时,现场支护围岩稳定,并且相比之前的支护方式在经济与效率上有很大的提高。     

An experimental investigation of the effects of operating parameters on the wear of lifters in tumbling mills

Lifters are usually used with mill liners to extend their life and to enhance the grinding and crushing efficiency. Although the lifters are durable wear parts but they will gradually worn and consequently their dimensions change during the course of operation. These changes in dimensions have a significant influence on the overall economic performance of the mills. Therefore, it is useful to know the relationship between the mill operation and the lifter profile, and the influence of lifter wear on the change in lifter profile. In this work, a laboratory mill which is capable of producing the required impact and abrasion grinding was operated both wet and dry. Many factors were varied such as: velocity, charge, ore size and different material for the lifters. Also the wear rate on the top and face of lifters are compared in the different conditions. It is found that the mill charge and the mill speed significantly affect the wear rate. Also, the results showed how size distribution affects the wear rate. The results can be interpreted in terms of the wear process in industrial scale mills over different operating conditions. The experimental results provide the possibility of including the lifter wear in optimising mill performance.     

XJM-S45型浮选机关键技术参数影响因素的研究

提出了XJM-S45型浮选机的关键技术参数可采用模拟放大方法确定的观点,并通过试验对比了不同叶轮转速、不同叶轮浸没深度、不同进气孔面积和不同调节环面积条件下的浮选机充气速率、充气均匀度和功率消耗的情况,找出了影响浮选机充气性能的主要因素,从而为大型浮选机的优化设计提供了依据。     

微细粒赤铁矿-石英体系的选择性絮凝试验研究

通过采用常规絮凝剂和新合成絮凝剂絮凝对单矿物和人工混合矿选择性絮凝试验,得出不同选择性絮凝剂对微细粒赤铁矿-石英体系的絮凝效果优劣顺序为:淀粉丙烯酰胺接枝聚合物＞磺化聚丙烯酰胺＞苛化玉米淀粉,综合考虑品位和回收率指标,以淀粉丙烯酰胺接枝聚合物效果最佳。当淀粉丙烯酰胺接枝聚合物接枝聚合物加入量为3mg/L时,沉降物铁品位为42%,铁回收率为91.42%,当用量为1mg/l时,絮凝沉降物最高品位为45%,相比原矿提高了12个百分点,为采用常规选矿方法进一步分选絮团创造了条件。