用分段崩落法回采矿柱时矿石损失贫化的确定

佩钦加镍公司开采倾角从0至60°～70°和厚度2～30米的矿体。这些条件不适于用分段平巷矿房法开采。因此,为进行放矿要在阶段间柱和矿块问柱(房间矿柱)下部于矿房底柱中补充掘进放矿漏斗天井。在崩落矿柱的放矿过程中,曾发生过混入上覆崩落岩石或死填废石的现象。     

矿柱回采工艺的改进

“西卡拉扎拉”矿于1972年开始地下开采,为了开采+170米水平以上三个阶段,国立采矿工业设计院设计采用了爆力运矿的阶段矿房法。矿床地质特征:矿体倾角为30°～42°,厚16～35米,矿石为磁铁矿-赤铁矿,含铁     

倾斜矿体的大矿房法开采

哥罗布拉戈达特矿务局北矿和瓦卢耶夫斯卡亚矿开采的倾斜矿体属层状矿体,倾角28°～30°,厚度10～20米。矿山采用的主要采矿方法是空场矿房法。此法经底板漏斗放矿,留有阶段支撑矿柱和房间矿柱,这些矿柱随后向空场崩落。这样,有将近一半的矿量待用低效的第二步骤开采,即矿柱回采。为了降低矿体开采中的损失贫化,探讨了扩     

露天坑底部合理的开采方法

迈卡因矿床,其上部水平矿体的倾角为80°～90°,向下逐渐变缓到55°～60°,矿体群乃是厚几十米的单一的块状矿体,矿石和围岩稳固,f=9～14和6～16。所研究的矿体区段,上部为采深已达180米的露天矿坑底,下部为220米水平(图1)。一步骤矿房已用分段平巷和横巷法开采,矿房间留有     

不稳定的软弱倾斜厚矿体的开采工艺

苏联矿山倾斜(25°～55°)矿体很多。在克里沃罗格铁矿区,占总可采面积的70％的矿体,倾角为42°～55°,厚度为30～60m。克里沃罗格铁矿区开采这类矿体应用最广泛的采矿方法是采场内重力运搬矿石的分段矿房法和分段崩落法。由于矿体的倾角限制沿矿体倾斜自流运搬的使用范围,采用这些采矿方法势必要准备大量的分段。     

爬罐浅孔留矿法在急倾斜薄矿脉开采中的应用

大吉山钨矿含钨石英脉属于高温热液裂隙充填矿床,矿脉近于东西走向,向北东倾斜,倾角65～80°,平均75°,单脉厚度0.01～3.0米,平均厚度0.4米。矿脉赋存于寒武纪浅变质砂板岩和闪长岩中,矿岩稳固和中等稳固,f=8～14。目前主要采用两种采矿方法,在矿脉密集区段采用深孔崩矿的阶段矿房法回采,     

阶段矿房法的深孔落矿新方案

阶段矿房法深孔落矿根据矿房的采准方式和凿岩设备在分层内的位置通常可分为两种方案:1.在天井横巷(或平巷)中打水平平行深孔;2.在天井中的凿岩硐室内打水平扇形深孔。实践证明,这两种方案在生产应用都受矿体倾角的限制,当回采倾角55～80°的厚矿体时,矿石损失率随落矿高度的增大而增大。本文作者在采矿设计中试验了斜自由面落矿和随后扩帮的水平分层新方案,在矿体围岩较稳固的条件下,成功地解决了回采倾角大于55°和倾角不稳定的厚矿体的“丢矿”问题,从而扩大了深孔落矿方案的应用范围。提高了矿山生产的经济效益。     

端部出矿的阶段矿房采矿法

自行设备大面积出矿和采后胶结充填的阶段矿房采矿法,盖依斯克采选公司从1976年起就开始采用。矿房长30～50米,宽15米,高60米;采准工作包括沿相邻矿房边界掘进从底盘运输平巷至顶盘运输平巷的横巷以及从横巷每隔10米掘进45～50°的装矿进路。凿岩水平通过斜坡道与脉外运输平巷联通。     

浅眼一次爆破法回采房间矿柱

<正> 我矿208号矿脉,属伟晶岩矿床。矿体厚5～9米,倾角55～80°,矿石稳固。顶底盘均为黑云母片岩,裂隙发育,中等稳固。设计用浅眼留矿法开采,回采损失率高达40％,其主要原因是矿柱回采困难。为此我们进行了浅眼一次爆破法回采间柱试验,获得了成功。选用二中段5号间柱作回采试验。间柱高20米,平均宽10米,水平厚6.2～10.8米,倾角65°。间柱矿量3000吨。两侧矿房均已采完,且最终放矿     

灵活应用有底柱分段崩落法

贵溪银矿二八○中段３～２矿体矿房，采用连续分段空场法回采不到５０％时，地表塌陷，矿房自由空间被大块围岩充填覆盖，致使该矿房难于继续回采，对此，改用有底柱分段崩落法进行补救，取得了显著的效果。该项目被评为贵溪银矿“八·五”科技成果一等奖。     

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。