采动影响巷道群围岩变形及支护修复实践研究

百善煤矿6537工作面地质构造复杂,断层、底鼓、薄煤带等给安全回采带来诸多不利因素。受6537采动影响,周围巷道剧烈变形,大量出现弯腿、弯梁(含崩牙)、断面缩小、严重底鼓等现象。通过对6537工作面回采动压影响巷道围岩变形的实测和分析研究,总结出了工作面回采对周围巷道稳定性及围岩变形影响规律,并针对性地进行修复,取得了较好的实践经验。     

机械化矿岩分采某锡矿山缓倾斜薄矿脉

缓倾斜薄矿脉脉内空间小,制约了机械化回采效率的提升。传统电耙出矿矿石损失大、贫化率高、回采经济效益差。通过运用先采矿体底板围岩,再回采矿体的矿岩分采方式可增加回采空间,为机械化开采创造条件。阐述了机械化矿岩分采技术方案原理,并以某锡矿山缓倾斜薄矿脉为例,讨论了回采工艺流程及相关技术措施。研究表明:机械化矿岩分采缓倾斜薄矿脉较传统电耙出矿方式能有效提高矿石回收率和回采效率,降低贫化率,对于高效回采类似矿体有一定的借鉴价值。     

综放工作面过薄煤带提质增效研究与实践

针对王坡煤矿3316综放工作面煤层厚度变化大、伴生有底矸夹矸等构造、工作面顶板和煤质控制困难等实际情况,通过对3316综放工作面过薄煤带期间顶板控制、生产工艺等环节问题查找,制定了顶板控制、煤矸分流、配采等措施提质增效。实施薄煤带管控措施后,原煤含矸率降低了5.81%,原煤灰分降低了1.67%,发热量提高了4.5%,提升了矿井经济效益,对其他综放面开采具有一定的指导作用。     

铜山口铜矿空场嗣后充填采矿法采场采切方案优化

铜山口铜矿N529采场经生产探矿后,矿体在下部变厚大,上部变中厚。因地表充填系统尚未建成,目前新建采场少。为早日投产,将此采场划为2个矿块回采。采用分段空场嗣后充填采矿法回采上盘矿体,结束后再采用上向式水平分层充填法回采下盘矿体。回采上盘矿体时,第一分段采切工程设计了2个方案,对2个方案的采切工程量、运矿距离、矿石损失贫化、采场建设时间、相邻采场回采影响、安全性、充填准备时间进行了比较,最终选择方案1作为上盘采切方案。     

桃江锰矿响涛源矿区开采方案探讨

针对桃江锰矿响涛源矿区缓倾斜、倾斜薄矿体的特点和现状,提出了对于矿体倾角≥38°的薄矿体,采用全面推进削壁充填采矿法方案；对于矿体倾角≤38°的薄矿体,则采用扇形推进削壁充填采矿法方案,并对这两种方案的采准切割、回采出矿、采空区处理等工艺进行了探讨.     

综放工作面快速过复杂条件探巷技术实践

枣园矿23081综放工作面受云盖山大断层影响,在掘进过程中遇大面积薄煤带及断层组,为详细探清工作面地质状况,在工作面中部进行巷探。针对23081工作面的复杂条件,提出探巷锚索梁支护、工作面调斜、开挖通风孔等解决思路,并根据实际情况,确定施工技术方案,安全快速地通过了探巷,最大限度地回采了煤炭资源。     

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。     

浅埋煤层回采巷道变形破坏特征与支护参数优化研究

以李家壕煤矿3-1煤层12108工作面开采条件为工程背景,综合采用顶板钻孔窥视观测、多基点位移监测、围岩松动破坏范围实测等方法深入了解回采巷道围岩变形破坏特征,在此基础上提出了4种巷道支护优化方案,通过采用数值模拟计算方法,并考虑经济效益,分别确定了受一次采动影响和二次采动影响回采巷道的最优支护方案,为浅埋薄基岩回采巷道支护参数的选择提供了依据。     

浅孔留矿法开采倾斜薄矿脉时围岩稳固性研究

浅孔留矿法适用于围岩中等稳固倾斜薄矿脉的开采。云南某金矿矿体赋存条件适合采用浅孔留矿法,但该矿回采指标极不理想。生产实践表明,采场围岩不稳固是造成回采指标不够理想的主要原因之一。为了研究围岩稳固性对回采指标的影响程度,必须研究岩体力学参数取值。运用Flac3D建立多种采场结构参数模型,加载后进行应力应变数据分析,模拟结果显示,在保持原有结构参数不变的条件下,将采场长度由32m增加到40m、顶柱高度由3m增加到5m,采场上下盘围岩在回采和放矿过程中能保持相对稳固。为了进一步证明模拟计算结论的可靠性,该矿就新方案进行了工业试验,结果显示,试验采场回收率达到70.31%,贫化率达到9.80%,与原有方案相比,回采指标有明显改善。可见,采用数值分析法来研究浅孔留矿法围岩稳固性,可以有效提高回采指标。     

厚煤层分岔区变厚度夹矸下回采巷道支护技术

厚煤层发生分岔现象较为普遍,上下分层间夹矸层厚度通常变化较大。当夹矸层厚度较小时,受上部煤层采动影响,夹矸层与下部煤层将会发生不同程度破坏,给下部回采巷道支护带来较大困难。以某矿9采区为工程背景,通过现场实测与采用理论分析,建立了巷道薄夹矸顶板刚化理论,分析了夹矸顶板刚化可行性和刚化后岩层的稳定性,形成了采空区薄夹矸下回采巷道的顶板夹矸稳定性分类分案。将巷道顶板分为夹矸层厚大于5m、3~5m和小于3m三类,提出了三类薄夹矸回采巷道的支护方案。     

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     

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。