某铅锌矿矿柱回采方法研究

某铅锌矿为生产多年的地下开采矿山,原采用房柱法开采,形成了270万m3的采空区和71万t高品位的铅锌矿柱。为解决空区安全问题、实现尾矿“零排放”,为深部采矿创造良好条件,提高矿山资源利用率,增强企业效益,设计采用全尾砂膏体充填治理采空区,在保证安全的基础上回采高品位铅锌矿柱,针对性提出了3种采空区治理和矿柱回采方案,并对3种方案进行经济技术比较,择优选择最佳空区治理和矿柱回采方案,并进行了相关设计。     

冬瓜山铜矿60~#线以北高大采场联合回采方案研究

在“隔三采一”回采顺序下,为安全高效回采二步骤垮落采场,需结合中间的一步骤采场联合回采。以冬瓜山铜矿60~#线以北大高采场为例,结合一步骤采空区垮落的特征,提出了3个或2个采场联合回采方案,通过数值模拟论证,验证了3个采场联合回采对隔离矿柱稳定性影响大,需采取安全措施保护隔离矿柱;2个采场联合回采时采空区稳定性较好。通过工业试验,3个采场及2个采场联合回采方案均取得了较好的应用效果。     

石人沟铁矿矿柱回采及采空区处理探讨

结合石人沟铁矿开采残留矿柱及采空区情况,提出几种回采矿柱的方案,并进行了详细分析选择;同时在采空区充填的情况下,制定了井上井下地压的监测方案。     

新疆某磁铁矿矿柱回采及采空区处理实践

通过对井下老采空区矿柱的分析研究,提出了以中深孔分段凿岩、集中爆破的方式回采矿柱,并在崩落矿柱后利用上盘围岩的失稳自然崩落充填处理采空区。经过一年的方案实施后,不但回收了大量矿石资源,而且很好的处理了采空区,为矿山在回采矿柱及采空区处理方面积累了宝贵的经验。     

复杂条件下矿柱回采的相似材料模型试验

在空区末充填的情况下回采矿柱,矿柱与采空区顶板的稳定性是一个关键问题。利用相似理论,建立矿柱回采的平面应力相似材料模型,通过观测模拟矿柱开挖过程的应力与变形变化情况,研究了狮子山铜矿西山特大空区下矿柱回采过程的应力变形的变化规律,结果表明,采用分步凹采预帮永久矿柱的回采方案是可行的,矿柱凹采过程中永久矿柱和采空区顶板足稳定的。矿柱回采的实践证明了相似材料模型试验结果是正确的。     

多中段空区稳定性分析及间柱回采顺序优选北大核心

以甘肃某铅锌矿为工程背景,针对矿山复杂条件下多中段采空区中遗留大量高品位的矿柱,如何安全高效回采残矿已成为提高矿山安全和经济效益的重要因素,通过对回采方案及复杂采空区的稳定性进行分析,探究最佳矿柱回采方案和回采顺序。根据研究区域的矿柱数量,对中段间、中段内开采顺序及方向进行组合,最终得出14个方案,并通过选取矿山的矿岩样品和尾砂,进行岩石室内力学参数试验,得出相应力学参数,并根据井下实际情况建立FLAC^(3D)模型。将折减后的岩体力学参数带入FLAC^(3D)数值模拟软件中,从应力、位移和塑性区等方面分析采区的稳定性,从而优选出中段自下而上、中段内采取隔一采一、由中间向两翼回采的方案。     

呷村银多金属矿复杂空区矿房矿柱回采方案优选研究

通过分析研究矿房矿柱回采的基本要求和方法技术特点,以呷村银多金属矿4206矿房矿柱为例,结合4206矿房空区、当前工程布置以及回采矿房矿柱分布等实际情况,提出了充填回采、分段崩落回采、大爆破回采3种不同的回采方案,并对方案的采切工程布置和回采工艺进行了简要介绍说明。最终经过技术比较分析、生产成本要求分析、生产规划要求分析,确定方案三为最优方案,并投入生产应用。     

矿山隔离矿柱回采稳定性分析及开采方案研究

冬瓜山铜矿在进行完大规模1步骤矿房回采和2步骤矿柱回采后,形成了大量的采空区和充填采场,致使岩体应力分布十分复杂,盘区隔离矿柱的回采条件已发生根本性改变。通过对开采状态的调研分析,以52-54线隔离矿柱为例,提出了2种隔离矿柱回采方案,从开采难度、矿石回收率、采切工程量等方面进行了对比分析,并结合数值模拟软件FLAC^3D对2种矿柱回采方案进行了模拟。模拟分析显示：方案1隔离矿柱在回采过程中侧壁出现了较大的位移,容易形成侧壁垮塌,并且其塑性区面积较大;方案2在隔离矿柱回采后,采场侧壁位移很小,对于在回采过程中出现的应力集中区域,减小矿房跨度,避免矿壁受到进一步破坏,回采作业对围岩的影响最小。通过综合比较,认为方案2较为合理,为可行性较高的方案。     

某铁矿矿柱回采安全性研究

某铁矿二采区一中段采用空场采矿法进行采矿,经过多年开采该中段未处理采空区体积已经达到40万m3,遗留矿柱矿量超过26万t,为了充分回收矿产资源矿山计划回采矿柱。由于现场未处理的采空区体积较大,而矿柱又是维持采空区稳定性的关键要素,可能部分矿柱的回采或破坏就会诱发一定规模的地压活动,威胁矿山的正常安全生产。所以在矿柱回采之前,对回采区域的矿柱进行安全性研究,可以指导矿柱回采的实施,进而保障矿柱的正常安全回采。结合矿山的现场实际情况,以应力增量理论为基础,采用工程地质调查、室内试验结合数值模拟的方法,对矿山二采区一中段需回采矿柱的安全性进行研究,确定了各回采矿柱的安全系数大小。研究结果表明矿山二采区一中段的矿柱处于安全状态,可以进行部分矿柱回收。     

盘区矿柱回采方案的优化研究

盘区矿柱回采厚度是影响资源回收率的重要因素之一。合理的盘区矿柱回采厚度不但能够提高资源的回收率和经济效益,而且能够降低矿柱回采过程中的安全风险。在提出不同的回采方案的基础上,对岩体力学参数进行合理的折减处理,并通过自下而上的三维实体建模技术建立分析模型,并在分析中以摩尔-库伦岩土模型为破坏准则。采用FLAC3D分析软件对盘区矿柱不同的回采厚度进行数值模拟分析,研究盘区矿柱及其周围采空区围岩内应力和应变的变化规律。通过对盘区矿柱不同回采厚度模拟结果的分析比较,确定了盘区矿柱合理的回采厚度,能够保证盘区矿柱安全的回采。最后通过技术经济分析比较,综合考虑技术、经济和安全等多方面因素得出结论,选择其中的最优回采方案。     

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     

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     

2014 second batch of rare earth quota released

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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