井下密闭漏风量测定法

完善的矿井通风系统往往需要价格昂贵的设备和耗用大量的人力;但是,其效率相对来说是较低的,有60～80%的新鲜空气并未到达工作面,而逸入回风道.假如能够降低漏风,通风效率即会有所改善.出现大量漏风的地点,是井下永久性密闭.为了测定密闭墙漏风风量,美国矿业局研究成功了一种简易测量方法,称为《风幛窗口测定法》.矿业局曾通过1:1模型和井下实际密闭用此法进行了测定,结果表明,此法是测量密闭墙漏风量的精确方法.要使所有密闭都不漏风是费时费钱的.现实的做法是只对那些怀疑漏风较为严重的密闭进行测定和修补.从井下密闭逸漏出来     

改变通风路线调节风压法及其应用

<正> 煤炭自燃的条件之一是由于采空区或煤柱裂隙中存在着长期连续的漏风。要减少这种漏风有两个途径:一是在所有漏风通道上构筑高质量的密闭墙;二是设法减少漏风通道两端的风压差,前者是过去的传统做法。但是俗话说:“没有不透风的墙”。无论多么严密的密闭墙,只要存在风压差,漏风就不可避免,只是随着密闭质量有提高其漏风量相应减少而已。因此,很久以来人门都在     

深井自然风压及采空区漏风特征研究

为保障深水平矿井自然风压的有效控制和利用,采用现场实测的方法,以滕东生建煤矿一采区为例,对自然风压的变化规律及由于其变化导致采空区漏风的现象进行了研究。研究表明:深水平矿井自然风压全年变化规律形如正弦曲线,自然风压的变化导致采空区存在规律性的进漏风趋势变化,当自然风压减小时,采空区密闭处密闭内外压能差变大,漏风趋势明显,出风量增加,若采空区密闭处进漏风趋势为进风,则密闭处进风趋势减弱,甚至反向。当自然风压增大时,采空区密闭处密闭内外压能差减小,进风趋势明显,进风量增加,若采空区密闭处进漏风趋势为漏风,则密闭处漏风趋势减弱,甚至变为进风。     

察哈素煤矿3101工作面及地表漏风联合测试及其防治

察哈素煤矿地表处于沟壑地区,所开采3-1煤层属于易自燃煤层。3101工作面开采过程中,由于矿山压力显现强烈,联巷密闭产生了一定程度的破坏,同时由开采活动在地表产生了比较大的裂缝,形成了密闭和地表漏风隐患,对工作面的安全开采形成了威胁。测试了3101工作面联巷密闭压差,根据风量测试结果计算出采空区漏风率。通过在地表裂缝释放SF6,检测到了地表漏风,并计算出了地表裂隙的最大漏风风速。分析了存在漏风的原因,通过采取减风减压、提高密闭质量、填补地表裂缝等措施,减少了采空区漏风,有效防治了采空区煤炭自燃。     

工作面联络巷密闭墙漏风对采空区自燃影响及预防

基于矿井煤层赋存与生产技术条件的实际情况,通过对工作面联络巷密闭墙构筑特点的深入研究,对可能通过工作面联络巷密闭墙的各种漏风形态进行了探讨,并在此基础之上深入研究了其对采空区浮煤自燃的影响,同时提出了针对性极强的应对密闭漏风的措施。实践表明,对密闭墙进行处理后,采空区浮煤自燃析出气体无自燃标志性气体产生,有效防止了工作面联络巷密闭墙漏风引起的采空区浮煤自燃的发生、发展,保障了工作面的安全回采。     

SF6示踪气体漏风通道检测技术应用

对于煤层自燃、易自燃矿井,及时掌握采空区的漏风通道对于自然发火的防治尤为重要。通过SF6示踪气体技术对古书院矿9#和15#煤之间的漏风通道进行检测,同时对15#煤二盘区西翼工作面沿线采空区密闭墙进行了漏风情况排查,找出了漏风严重的密闭墙,并提出了封堵漏风通道措施,为降低采空区自然发火概率提供了保障。     

古书院煤矿153303老空区漏风通道检测

矿井回采完毕后老空区周边巷道密闭因为长期挤压变形产生漏风现象,对漏风点的准确定位可有效防止老空区漏风产生的自燃火灾现象.本文以古书院煤矿153303老空区为研究对象,采用气体示踪法检测该区域密闭是否存在漏风通道,示踪气体为SF6.研究结果表明测试区域存在3个漏风点,结合漏风情况制定了防止老空区自燃措施.本文研究成果对于...     

喷注罗克休泡沫材料在处理石门向采空区漏风中的运用

结合大水头煤矿煤层自然发火的实际,详细介绍了采用砌筑双密闭墙,墙间注罗克休泡沫封堵剂处理密闭漏风的技术方案及施工工艺,为特殊条件下快速处理漏风,提供了新的技术途径。实践证明:应用压注罗克休技术堵塞了采空区漏风通道,减少采空区漏风,消除煤层自燃隐患,从根本上达到治本的要求。     

高瓦斯矿井密闭墙前瓦斯治理

针对密闭墙前瓦斯浓度超限的问题,东瑞煤业结合岩层条件,对5道密闭墙及周围密闭巷道进行注浆加固,选用较好的化学材料,有效防止了密闭漏风,遏制了密闭墙前瓦斯等有毒有害气体泄出,控制了密闭墙瓦斯浓度,保障了闭墙瓦斯浓度不超限,为矿井安全生产奠定了基础。     

新型封闭材料在处理石门向采空区漏风中的运用

文章结合大水头煤矿煤层自燃发火的实际,详细介绍了采用砌筑双密闭墙,墙间注罗克休泡沫封堵剂处理密闭漏风的技术方案及施工工艺,为特殊条件下快速处理漏风,提供了新的技术途径。实践证明:应用压注罗克休技术堵塞了采空区漏风通道,减少采空区漏风,消除煤层自燃隐患,从根本上达到治本的要求。     

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。