水平型石英脉金矿废石充填对顶板的支撑作用

为论证水平型石英脉金矿采用废石充填的可行性,根据水平型石英脉金矿顶板围岩稳固性和采空区垮塌特征,建立了水平型脉金矿采空区顶板的力学模型。通过对水平型石英脉金矿的废石充填对顶板围岩的支撑作用进行分析,发现在"危险区域"中,废石充填可以有效地控制采空区顶板垮塌过程,从而认为,水平型脉金矿也可以采用简单价廉的废石充填法开采,使以往常常只能采用空场法开采以实现低成本的观念发生很大改变。     

某铁矿废石充填采空区保护竖井安全的可靠性分析

某铁矿已有竖井保安矿柱范围内存在老采空区,采空区采用废石进行了充填处理。为验证废石充填采空区保护竖井安全的可靠性,采用大型有限元模拟软件对采空区围岩位移和塑性破坏区进行模拟计算,得出采空区采用废石充填后围岩位移和塑性破坏区得到有效控制,塑性破坏范围未波及到竖井,能够起到保护竖井安全的作用。     

潘洛铁矿采空区处理施工方案

潘洛铁矿2号矿体采空区上盘和顶板暴露面积较大,而且空区形状不规则,一旦发生空区围岩失稳,将对整个矿山带来巨大灾难.为实现安全生产,采用废石充填天井处理采空区.通过对传统掘进工艺(吊罐法、深孔爆破法)、全断面掘进工艺进行比选,从而确定选用全断面钻进法施工废石充填井.     

巷道过采空区围岩控制技术研究

15102回风巷掘进至320 m处时揭露15^#煤1^#采空区,为保证巷道安全贯通,对采空区内冒落的破碎矸石进行充填加固,使巷道形成支撑体;同时,采用注浆加固、临时支护和永久支护方式提高支护强度,避免掘进过程中顶板冒落、垮塌。支护后通过监测围岩变形量可知,采空区充填及巷道围岩加固措施取得了良好效果。     

膏体—废石联合充填技术及应用

为达到较高的膏体接顶率,根据采场顶板情况采用不同的管线安装方法。会泽矿区膏体废石充填比例约为1.41-1.77,空区充填率达到90%以上,成本为91.39-97.74元/m3。联合充填体强度高,整体性好,能够支撑铲运机的正常行走且不会开裂下沉;围岩变形小,基本无矿石跨落。3 a废石充填量为23万m3,节约占用土地费用、提升运输费用、降低充填综合成本,经济效益达到3 585.35万元。联合充填缩短了顶板的暴露时间,减少了顶板垮塌及工伤人次,安全效益突显。     

膏体—废石联合充填技术及应用

为达到较高的膏体接顶率,根据采场顶板情况采用不同的管线安装方法。会泽矿区膏体废石充填比例约为1.41~1.77,空区充填率达到90%以上,成本为91.39~97.74元/m3。联合充填体强度高,整体性好,能够支撑铲运机的正常行走且不会开裂下沉;围岩变形小,基本无矿石跨落。3 a废石充填量为23万m3,节约占用土地费用、提升运输费用、降低充填综合成本,经济效益达到3 585.35万元。联合充填缩短了顶板的暴露时间,减少了顶板垮塌及工伤人次,安全效益突显。     

大采空区灾害控制技术的数值模拟

不少金属矿山由于前期民采在井下遗留下大小不一的众多空区,其中某些采空区体积多达数万立方米,暴露面积达数万平方米,是造成大规模冲击地压及塌陷隐患的主要诱因。为保证下部及相邻中段安全回采,提出在合理水平实施废石充填,形成应力隔离层。以某金矿为例,采用数值模拟手段研究了大采空区充填前后围岩应力及剪应变增量情况。分析计算结果表明,充填处理后,大采空区围岩应力集中程度明显减小,拉应力区域相应减少且值较小,剪应变增量值减小且剪应变增量区域不贯通,安全隐患得到消除。     

基于FLAC3D对某铜矿深部开采地压活动规律研究

介绍了地压活动规律对矿山深部开采的重要影响,通过应用FLAC~(3D)软件对某铜矿59#矿体开采过程中的两种工况进行数值模拟计算研究,发现59#矿体在开采至十五中段时,对围岩扰动较小,不会出现顶板大面积冒落的情况;开采对3#采空区稳定性影响最大,对2#采空区稳定性影响最小;废石充填对维护空区稳定有一定作用,但作用不大;随着59#矿体开采深度的不断增加,其对断层的影响程度也逐渐增加;废石充填对断层稳定性影响较小。从而得出随着开采深度的增加,对围岩扰动越来越大,围岩稳定性降低,顶板发生突然冒落的可能性较大,一旦顶板发生突然冒落,井下会出现较大响声和振动,但由于该铜矿采用崩落法开采,采场上部有大量冒落覆岩,顶板突然冒落不会形成冲击地压。     

急倾煤层采空区控顶方式对采场围岩稳定性影响

为了确保水体下急倾斜煤层的安全开采,基于龙湖煤矿南二采区急倾斜煤层的赋存条件,采用离散元UDEC2D数值计算方法,研究了急倾斜煤层开采采空区控顶方式对采场围岩控制的效果。结果表明:采空区不进行充填,采场围岩变形最大,顶板变形呈抛物线型;采空区部分充填下部40 m范围内,顶板变形呈线性增长趋势,而未充填部分顶板变形呈抛物线型增大趋势;整体充填不同充填体强度下顶板位移均呈近线性变化,充填体弹性模量为0.5 GPa即可满足现有采深条件下支撑顶板的要求;部分充填和整体充填均随着充填体强度的增加,顶底板变形呈降低趋势,且整体充填顶板控制效果显著高于部分充填。     

湘西金矿试验采场的有限元分析

湘西金矿2241试验采场的矿体为缓倾斜薄矿脉,拟采用机械化水平分层削壁充填法回采,定向抛掷爆破围岩充填采空区。为了了解回采过程顶板的稳定性,用有限元数值分析方法,模拟采场回采过程,分析其应力、位移变化情况。稳定性分析结果表明:该采矿方法设计合理可行、安全可靠。     

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     

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     

2014 second batch of rare earth quota released

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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     

China rare earth market review

正November 21~30,2014Due to weak demand from downstream industries,transactions of rare earth in Chinese domestic market were inactive.It was difficult to sell any rare earth products except for dysprosium oxide and terbium oxide.Suppliers lost confidence in recent market.Demand for rare earth products was soft.Consumers continued to take a wait-and-see attitude.Rare earth export market remained slow.     

Galaxy Magnets achieved the net profit of 34.02 million yuan in the first six months of 2014

正Galaxy Magnet announced its financial results for the first half of 2014 on August 14.For the first six months ended on 30 June 2014,Galaxy Magnet achieved operation income of RMB 182.3 million,up8.40% over the same period of 2013,and the net profit attributable to the shareholders of the listed company of 34.02 million yuan,increasing 35.49% over the same period of last year.Stable performance increase was led by development of new customers and application market of magnets.