冻结管外环形空间封堵用的缓凝水泥浆材料研究

针对全深冻结法施工中的冻结管与冻结孔之间的环形空间封堵问题,研发了一种缓凝水泥浆材料。通过研究缓凝剂对水泥浆凝结时间的影响规律,确定了缓凝剂的合理掺量。通过在缓凝水泥浆中掺加钠基膨润土和悬浮剂来控制缓凝水泥浆的沉淀性能,配制成了缓凝效果好、密度均匀、后期强度高的缓凝水泥浆材料,满足了现场施工对缓凝水泥浆性能的要求。该缓凝水泥浆材料应用于大海则煤矿立井冻结项目,效果良好。     

营盘壕煤矿主井冻结孔环形空间井内注浆封堵技术

营盘壕煤矿主井采用全深冻结法施工,冻结壁融化后,会在冻结孔中上部孔壁与冻结管之间、井筒外壁与围岩之间形成导水的"环形空间",增加矿井排水费用,威胁矿井安全。由于缓凝水泥浆置换高度受限,导水通道未采用水泥浆封闭。通过对冻结孔"环形空间"进行注浆封堵,对井筒外壁与围岩之间进行壁后注浆充填,实现了对导水通道的有效封堵,收到了预期效果。     

井筒马头门处冻结管周围环形空间处理方法研究

该文介绍了立井井筒全井深采用冻结法施工时,马头门处冻结管周围环形空间的处理方法,并根据实际应用情况从不同方面作了分析比较,从而提出了推广采用缓凝水泥浆置换冻结孔内粘土处理方法的建议。     

缓凝水泥浆置换冻结孔泥浆封水技术

鄂尔多斯等西部地区的含水地层,以富含孔隙水的白垩系砂岩层为主,且岩石强度低,立井井筒多采用全深冻结法施工,冻结壁解冻后,冻结孔与冻结管外的环形空间极易成为导水通道,严重威胁着矿井安全。门克庆煤矿副立井采用全深冻结法施工,施工单位中煤五公司第三工程处与中国矿业大学合作,开展了冻结孔缓凝水泥浆液固管技术研究和应用工作。该井筒冻结孔施工完毕,在下冻结管之前,采用缓凝水泥浆液置换冻结孔造孔泥浆,取得了圆满成功,收到了预期效果。     

冻结孔环形空间充填材料密度试验研究

为防止冻结壁融化后冻结孔成为竖向导水通道,威胁矿井安全,冻结孔必须进行固管充填处理。针对冻结孔钻孔泥浆置换与冻结管下放安装工程中对特定密度水泥浆的要求,应用颗粒级配理论,研制出密度分别为1 400、1 350、1 300、1 250 kg/m3的高稳定性浆液,该实验研究工作对高稳定性特定密度冻结孔置换水泥浆研究具有借鉴意义。     

某铁矿冻结孔的缓凝水泥浆固管充填技术

近年来,冻结法凿井技术在我国富水岩层矿井建设中的应用越来越广泛。为防止冻结壁融化后冻结孔成为竖向导水通道,威胁矿井的安全,冻结孔必须开展固管充填处理。针对某铁矿回风井冻结法凿井面临的地层条件及钻孔泥浆特点,通过室内及现场试验研究,获得了具有良好稳定性、较长缓凝时间且能与钻孔化学泥浆相容的缓凝水泥浆液配方,并研究制订了合理的冻结孔固管充填施工技术与工艺。冻结孔固管充填技术在该矿井的成功应用,证实了所研发的缓凝水泥浆液配方及相关施工技术与工艺的可行性与可靠性。     

大直径冻结立井安全快速施工

纳林河煤矿2号副立井净直径10.5m,最大掘进直径15.5m,井深583.95m,冻结深度521m。井筒主冻结孔采用缓凝水泥浆固管封水,封堵冻结孔竖向导水通道,可避免冻结壁解冻后,冻结孔导水,威胁矿井安全。井筒掘进时,采用双联伞形钻架凿岩,成功地解决了大直径井筒全断面一次钻眼爆破难题,凿岩效率提高了40%,缩短了循环时间,加快了施工进度,掘砌外壁月成井有3个月达到或超过100m。另外,冬季采暖,保证工程质量和顺利施工,也是一项成功经验。     

引流注浆封堵深基岩冻结井筒冻结孔涌水技术

针对我国西部地区深基岩冻结井筒冻结孔涌水水害技术难题,以胡家河矿主立井冻结孔水害治理项目为工程背景,在分析封闭不良冻结孔环状导水通道生成及涌水机理基础上,创新性提出一种引流注浆封堵深基岩冻结井筒冻结孔涌水技术。工程实践验证分析研究结果正确,该技术能高效快速治理冻结孔涌水水害。     

冻结孔水泥浆封水结构冻融损伤特性试验研究

水泥浆结石体强度及其与周围介质胶结面的粘结力的大小是影响冻结孔封孔防水效果的主要因素,且长期冻融作用下对水泥浆液结石体内部微观结构产生较大的损伤,使其封孔防水效果进一步劣化。针对此种情况,文章采用模拟试验方法,系统研究了不同配比缓凝水泥浆结石体强度及与冻结管、孔壁围岩胶结面粘结力在冻融作用下损伤变化规律。结果表明:冻融作用下其力学特性明显降低,提高结石体的强度且掺加适量的膨胀剂能够显著提高结石体与周围介质粘结力,有利于减小其冻融损伤,提高冻结孔封孔防水效果。     

冻结立井井筒快速施工技术在钱营孜煤矿的应用

钱营孜煤矿为实现新副井井筒顺利开挖,提高表土层井筒掘进速度,提出了冻结立井井筒快速施工技术,即采用主排孔+辅助孔+防片孔冻结方案。现场实践表明,该方案明显提高了井筒试挖段井帮稳定性,为井筒表土段外壁高效掘砌创造了良好的冻结条件,取得了良好的工业效果。     

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