带—网—栓式矸石袋巷旁充填支护体力学性能研究

针对沿空留巷中矸石充填体的大流变性和低支护强度等问题,提出带—网—栓式矸石袋巷旁支护技术方案。该技术选取钢带、锚网、锚栓等作为矸石袋的侧向支护材料,以此约束矸石袋的横向变形、增加矸石袋的围压,最终提升矸石充填体的支护性能。通过对矸石充填体的侧向分别添加钢带、锚网、锚栓进行承压力学试验后,矸石袋的最大承载能力提高了2～5倍。同时,该技术在山西左权天一煤业公司3102工作面进行了工业试验,结果表明其具有促使巷道围岩变形减小、巷旁支护效果显著等优点,取得了较好的经济技术效果。     

脆性围岩炮采工作面沿空留巷技术实践

针对脆性围岩、裂隙发育条件下沿空留巷技术的局限性,以新庄矿为工程背景,对脆性围岩留巷稳定性控制、巷旁充填系统工艺和巷旁充填体参数等进行了研究与设计,并通过矿压观测对围岩表面变形、围岩深部位移进行了分析评价。结果表明:在围岩松脆、裂隙发育和煤壁片帮严重的条件下,采用"锚网-锚杆-锚索"联合支护、煤壁喷浆预加固以及充填体加强支护等技术,能控制留巷围岩变形,抑制煤壁片帮;新型高水材料巷旁充填体具有速凝早强和较强的抗变形能力,而且充填工艺简单、系统机械化程度高,能很好的适应脆性围岩炮采条件下沿空留巷。     

厚煤层综采沿空留巷支护技术

为了研究厚煤层综采沿空留巷支护技术,通过沿空留巷围岩控制原理分析和工程实践,提出了巷内补强支护、巷旁充填支护和临时辅助支护为一体的支护结构体系.巷内补强支护采取补打高预应力锚索和下帮煤体注浆加固的措施;巷旁充填支护主要是采用高水速凝材料构筑巷旁充填体,为了提高巷旁充填体的承载和抗变形能力,充填体中置入锚栓,表面用金属网...     

锚柱网预支撑袋铸混凝土沿空留巷技术

通过分析华晋沙曲煤矿已完成24207采区采用巷旁充填沿空留巷存在的缺陷和不足,结合相邻24208回采区地质条件及原有掘进的巷道现存状况,对24208回采区提出了锚柱网预支撑袋铸混凝土沿空留巷技术,并进行了支护试验和矿压监测分析。结果表明:应用锚柱网预支撑袋铸混凝土隔墙支护技术,巷旁预支撑构件HT锚柱早期及时切顶卸压能够在留巷过程中有效控制巷道变形,提高沿空留巷围岩稳定性,优化了沿空留巷支护结构、支护参数及施工工艺,确保工作面安全高效回采,可供类似条件沿空留巷支护借鉴。     

普通混凝土巷旁充填沿空留巷试验

基于缓斜中厚煤层综采工作面沿空留巷顶板岩层运动规律及其变形特征,分析了采用普通混凝土进行巷旁充填沿空留巷的可行性,提出了支护体的特点和性能要求,并设计出合理、经济的支护体系。试验表明,采用普通混凝土巷旁充填结合巷内锚、网、索联合支护、巷旁充填体两侧采用单体液压支柱临时支护以及采空区侧用锚索加强支护的护巷方式,充分弥补了普通混凝土初凝时间长、初期强度低的缺点,能有效地控制顶板岩层。     

新景矿工作面巷旁充填沿空留巷支护技术应用

为提高煤炭回收率、降低巷道开拓成本,以新景矿3213工作面为工程背景,开发了巷旁充填沿空留巷支护技术。3213第一辅助进风巷留巷前巷内采用锚杆+锚索+钢带+金属网联合支护;留巷后,巷旁采用柔膜混凝土墙+对拉锚栓+钢带+钢筋支护,巷内采用锚索补强支护、单体支柱+π型梁临时支护;技术应用后,实现了留巷围岩的稳定控制。     

临汾宏大煤矿矸石充填开采沿空留巷围岩稳定性控制技术

临汾宏大煤矿8302工作面采用选充一体化工艺开采,分析矸石充填开采沿空留巷围岩变形规律,确定采空区81.5%矸石充实率,结合锚带网+锚索巷内基本支护、单体支柱挡板与夯实胶结体联合两种沿空留巷支护方案,进行围岩稳定控制技术研究。经过两个月围岩变形量数据监测,围岩位移变形量大幅降低。     

沿空留巷技术在东海矿的应用

在东海煤矿的23#煤层左四副巷(左五路工作面)采用码石墙、锚网、锚索、钢带等支护手段,推广了沿空留巷技术,采用锚杆作为巷内基本支护,锚索加强巷旁支护,有效控制了围岩变形,较好地解决了支护矛盾,缓解了采掘接续紧张,增加了经济效益.     

新强煤矿沿空留巷支护方式数值分析

依据新强煤矿五采区45051工作面沿空留巷支护方式,针对巷旁充填体梯形形状及巷道支护方式采用FLAC3D数值模拟软件进行相关分析。对巷旁充填体内是否预设锚栓加固措施的不同强度进行模拟分析。结果表明：45051工作面巷旁充填材料配比强度应高于10 MPa,并应在充填体内加锚栓强化。     

贺西煤矿柔膜混凝土充填沿空留巷支护技术应用

贺西煤矿为提高煤炭回收率、降低巷道开掘成本，以3412工作面运输巷为工程背景，提出了柔膜混凝土充填沿空留巷方案，开发了柔膜混凝土充填沿空留巷支护技术，对3412工作面运输巷顶板和回采侧巷帮采用高预应力锚（网）索加强支护，采空区侧巷旁采用柔膜混凝土充填墙体+预留高强锚栓加强支护，巷内采用高阻力单体支柱进行临时加强支护。技术应用后，实现了3412工作面运输巷留巷围岩的稳定控制。     

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。