马坑铁矿采场稳定性数值模拟研究

针对马坑铁矿缓倾斜中厚矿体的开采技术条件和采矿方法,运用三维有限元数值方法模拟分析了采场结构参数和回采顺序,数值计算结果对矿山生产具有指导意义.     

大断面进路充填法在某缓倾斜中厚铜矿床的应用

采用进路充填采矿法回采缓倾斜中厚矿体,在矿石回采过程中存在着贫化损失率高、回采效率低等问题。某缓倾斜中厚铜矿体在进路充填回采过程中,通过优化进路充填采场断面,降低了贫化损失率,提高了采矿效率,取得了较好的技术经济指标,可供类似矿山参考。     

缓倾斜极薄矿体采场结构参数优化研究

在开采缓倾斜极薄矿体时,合理的采场结构参数是维护采场稳定性、提高矿山生产效率的有效措施。结合南温河钨矿缓倾斜极薄矿体开采的采场设计,针对0.5,1m厚的矿体,分别设计了6种采场结构参数方案,应用FLAC~(3D)软件进行数值模拟,探究合适的采场结构参数。研究表明:对于0.5m厚的矿体,采用0.5m的间柱宽度、3m的回采宽度可以更好地维护采场稳定,降低矿石损失率;对于1m厚的矿体,同样采取0.5m的间柱宽度、3m的回采宽度的方案能达到最优的效果。     

金厂河铅锌矿大直径深孔采矿方法试验研究与应用

保山金厂河铅锌矿主矿体为低品位缓倾斜中厚矿体,平均厚度40 m左右,地下开采采用斜井开拓,设计能力1 500 t/d。为保证高效安全开采,矿房矿柱采用两阶段回采。通过对矿体形态、工程地质条件及类似矿山的生产案例研究,提出采用下向大直径深孔侧向崩矿嗣后充填方案进行回采。选取19#采场作为工业试验采场,试验结果表明,下向大直径深孔落矿工艺达到了低成本、安全、高效开采的目的,取得了良好的经济效益及社会效益。     

缓倾斜中厚矿体回采数值模拟分析

缓倾斜中厚矿体的回采由于受到矿石运搬和采场顶板管理问题的困扰,成为矿山生产难题,也没有固定的经验可言。为研究此类矿床的开采方式,依据特定矿山的矿床赋存条件和开采技术条件,选择相适应的采矿方法,采用理论和数值模拟相结合的方法进行采矿方法安全性的数值模拟分析和采场结构参数的确定,最终选择技术可行、经济合理的采矿方法。     

群空区下厚矿体二步骤采场回采顺序优化研究

针对某大型岩金矿山缓倾斜至倾斜厚矿体空场回采嗣后崩落二步骤采场高应力、高位移、高塑变的"三高"复杂开采技术难题,综合运用工程技术和经济学原理定量分析优化确定了隔一采一空场回采嗣后放顶的回采及空区处理方案,生产实践证明,该方案能确保矿山资源得到高效经济安全回采,满足矿山改扩建2500t/d的生产能力需求。     

云南某铁矿无底柱崩落法悬顶产生原因及治理措施

云南某铁矿在矿石回采过程中存在大量悬顶现象,降低了矿石回采率,同时也是矿山生产的安全隐患。研究人员通过现场调查矿山工程地质资料、设计图纸及施工钻孔,对矿山回采过程中悬顶产生的原因进行分析,发现悬顶产生的主要原因包括矿山岩石稳固性差、采场设计参数不合理、工人未严格按照设计钻孔施工等因素。针对现有悬顶采取补打倾斜炮孔、增加回采进路的处理措施;对后续生产减少悬顶、提高回采率采取加强钻孔施工作业管理与验收、合理布置采场参数、增加装药验收等措施。通过一系列设计、施工、管理措施,矿石回采中悬顶现象大幅减少,矿石回采率明显提高,矿山增效明显。     

缓倾斜薄矿体矿柱回采采场围岩稳定性研究

为解决缓倾斜薄矿体矿柱安全高效回采这一难题,对采场围岩稳定性进行研究是非常必要的。以三山岛金矿平里店矿区为工程背景,在前期现场调查、室内力学试验及岩体力学参数工程处理的研究基础上,运用RMR分级法和Q系统分级法分别对缓倾斜薄矿体矿柱回采围岩质量进行分级研究,得出采场围岩稳定性一般;分析了缓倾斜薄矿体采空区顶板破坏机理,并基于Burgers体建立了缓倾斜薄矿体采空区流变力学模型,为采场支护提供了理论依据技术支持;设计了缓倾斜薄矿体矿柱回采采场围岩应力实时监测系统,得到了采场围岩应力变化规律,现场实践证明：监测系统精度高、运行稳定。     

基于精细建模技术的深部采动过程综合集成系统

深部地下开采中采动应力是导致采场冲击地压,造成片帮、冒顶乃至岩爆地质灾害的显著因素。针对深部开采过程中基本生产单元--采场回采过程中采动应力场的时空演化规律进行研究,提出深部采场精细建模技术,构建采动岩体层次细节模型、采动行为动态仿真模型、多元异质采动岩体场元模型和采动过程动态调控设计参数化自适应优化模型;整合静态场景建模技术、生产工艺动态仿真技术、采动过程应力场信息动态可视化技术、动态调控设计方案预演技术,形成深部采场回采过程综合集成系统;进而探求回采过程中采动行为变化与采动岩体场元变化间的动态解译规律,揭示回采过程应力场的时空演化过程,最终为采场开采方法选择、支护时机与位置预测、回采参数优化提供指导,为采场安全生产提供科学依据和技术支撑。     

基于拓展的Mathews稳定图法的采场结构参数优化北大核心

合理的采矿结构参数是保障金属矿地下开采的前提。为了优化缓倾斜破碎金矿体的采场结构参数,以采场稳定概率大于95%为目标,引进拓展的Mathews稳定图法来优化采场最大跨度和暴露面尺寸,并采用考虑岩梁自重的弹性力学简支梁等理论进行验证。结果表明:当采场长度80 m时,回采进路跨度小于4.36 m时即可保证采场不会破坏;当采场长度80 m时,采场顶板跨度为4.3 m,采场上盘跨度为3.0 m,采场稳定概率能达到95%;优化后的上向进路充填法采场结构参数为3 m×3.5 m。现场工业试验表明:采场结构参数条件下回采过程中采场顶板及围岩未发生垮落及剥落现象,采场稳定性良好。因此,基于拓展的Mathews稳定图法适用于缓倾斜破碎矿体的采场结构参数优化。     

Current situation and future trend of China rare earth luminescent material industry

<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth     

China rare earth market review

正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products     

Annual Report analysis of Chinese rare earth-related listed companies in 2013

<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy     

Market opportunities and challenges for rare earth polishing powder

正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium     

Baotou Research Institute of Rare Earths developed a new RE alloy preparation technology

正Pyrometallurgy Laboratory of Baotou Research Institute of Rare Earths had independently developed a new preparation technology of rare earth alloy for NdFeB.The alloy can remarkably enhance the coercivity of NdFeB magnet but also evidently reduce the production cost of the magnet.The new master alloy was prepared in the kA pilot-scale electrolytic cell by the independent technology.The rare earth master alloy can be used as the raw material for NdFeB.Compared     

矿用防爆轴流对旋主要通风机叶片ANSYS模态分析及应用

高效节能矿用防爆对旋主要通风机的叶片是主要通风机运行的关键部件,叶片在运行时不断受到气流的作用力,从而使叶片产生振动,当叶片振动的频率与叶片的固有频率接近时,容易产生共振从而导致叶片的断裂。一旦叶片断裂时,对主要通风机的安全运行产生致命的影响,从而导致矿山、化工等企业发生重大事故,将会产生不可估量的损失。基于有限元分析软件ANSYS,对高效节能矿用防爆轴流对旋主要通风机叶片进行模态分析及产生对应的六阶模态频率,对主要通风机叶片的运行频率、固有频率及产生的共振问题进行了原理分析,并且解决了叶片频率共振的问题,从而为主要通风机叶片结构设计提供理论依据,并对主要通风机叶片的安全运行提供保障。     

2013 NdFeB export analysis

<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586     

Market and recycling of NiMH battery

<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH     

China rare earth market review

正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to     

唐口煤矿深部复杂开采工作面瓦斯分源涌出规律研究

研究工作面瓦斯涌出规律对工作面瓦斯治理有重要意义。为了得到唐口煤矿深部3号煤层复杂开采条件下工作面回采时期瓦斯涌出时空演化规律,选取6304工作面作为对象,采用实测方法研究6304工作面瓦斯涌出规律。结果表明:6304工作面瓦斯涌出量为6.534 m³/min,其中煤壁占34.27%,落煤占29.62%,采空区占36.11%;沿工作面倾向由低到高,瓦斯浓度整体为上升趋势,其中1—76号架工作面瓦斯浓度小于0.20%,76—102号架瓦斯浓度上升明显,最大为0.387%;上隅角的后部采空区是工作面的瓦斯主要涌出源,上隅角1号测点瓦斯浓度0.78%,上隅角周边3号、5号、7号、8号、9号测点瓦斯浓度平均为0.643%;周期来压时,上隅角瓦斯相对平时较高。研究为针对性的瓦斯分源监控与灾害防治提供基础。