陶粒玻化微珠粉煤灰隔热混凝土性能试验研究

以页岩陶粒、玻化微珠和粉煤灰为隔热基材,研制出一种隔热混凝土,可用作深井高温巷道热源屏蔽材料。利用正交试验方法,对隔热混凝土的隔热性能和力学性能进行试验研究,考察陶粒取代率、玻化微珠取代率及粉煤灰取代率对混凝土导热系数和抗压、劈裂抗拉强度的影响。结果表明:陶粒和玻化微珠对混凝土各方面性能均有显著影响,且影响规律一致,皆随取代率的增加,隔热性能显著提高,但力学性能有所下降。粉煤灰取代率在30%以内,影响较小,可使混凝土隔热性能有所改善;但力学性能先提高,后降低,其最佳掺量为10%。     

深井煤矿高温巷道新型隔热材料试验研究

随着矿井开采深度的增加,高温热害问题日益突出,通过正交试验的方法,以陶粒、玻化微珠和粉煤灰掺量作为实验变量,研制出一种新型隔热材料,其导热系数仅为普通混凝土的1/8;对各实验变量对于材料的表观密度、导热系数、抗压、抗拉、抗折强度的影响进行了研究,通过功效系数法进行分析,最终得出新型隔热材料的最佳掺量配比为:陶粒掺量为粗骨料的40%、玻化微珠掺量为细骨料的60%、粉煤灰掺量为胶凝剂的20%。试验结果表明,新型隔热材料施工工艺简单,成本低廉,可以满足深井高温巷道隔热要求,值得大力推广和使用。     

矿井高温巷道喷射隔热混凝土正交试验研究

针对当前深部矿井出现的高温热害问题,提出采用喷射隔热混凝土材料封闭巷道壁面,以从源头上隔绝热源。采用正交试验的方法分析了陶粒、玻化微珠和粉煤灰3种因素对隔热混凝土材料表观密度、导热系数、抗压、抗拉及抗折强度的影响。结果表明,陶粒和玻化微珠能够显著改善材料的隔热能力,同时也会降低其力学性能,粉煤灰在低掺量下能够改善材料的表观密度和隔热能力,但也会造成强度的下降,其总体影响不如前两者。通过功效系数模型分析,得出最优配比。试验配制出的混凝土满足轻质的要求,导热系数约为普通混凝土的1/5~1/7,具有明显的隔热效果,为矿井热害治理提供参考。     

尾矿基发泡水泥隔热材料性能增强工艺研究

以尾矿为原料制备发泡水泥隔热材料是实现尾矿大宗利用的有效途径,但尾矿的掺入会使发泡水泥隔热材料的综合性能受到影响。针对这一问题,通过对钼尾矿进行机械力活化来提高其火山灰活性,用活化后的尾矿制备发泡水泥隔热材料。通过对样品的抗压强度、抗折强度、导热系数、泡孔结构等进行表征,研究尾矿活性与材料保温隔热性能和力学性能的内在关系。结果表明,发泡水泥的保温隔热性能和力学性能随着尾矿活化指数的提高而增强。将尾矿在220 r/min的转速条件下球磨240 min,钼尾矿活化效果较好,所制发泡水泥隔热材料的综合性能最优。      

三种矿用隔热材料性能对比试验研究

为了解决高温矿井热害问题,利用玄武岩纤维、玻璃纤维、玻化微珠分别配合水泥、砂子、高强陶粒、水等材料制作了3种矿用隔热材料,测定了3种矿用隔热材料的导热系数与抗压强度。通过对比分析,掺和玄武岩纤维的试验材料,其确定导热系数为0.1323W/(m·K),抗压强度为10.98MPa,在3种矿用隔热材料中综合性能最优。     

深井巷道降温的一项新技术

随着煤矿开采深度的增加,深井热害问题日益严重。针对深井降温的实际情况,提出一种新理念—"主动降温",以及一项新技术—玻化微珠隔热结构。介绍了玻化微珠和玻化微珠隔热砂浆的主要性能,通过分析得到了玻化微珠隔热结构热交换原理,论述了玻化微珠隔热结构这一新技术在深井巷道降温中的应用前景。     

铁尾矿路面基层材料力学性能与耐久性能研究

为了探讨铁尾矿大规模资源化利用的新途径,以无侧限抗压试验结果（试件中水泥、碎石、铁尾矿和改性生物酶的质量比为5∶30∶68∶2）为基础,研究了聚丙烯纤维掺量对路面基层材料的力学性能和耐久性能的影响。结果表明,在聚丙烯纤维掺量为1.5 kg/m3的情况下,试件的劈裂抗拉强度达到0.396 MPa,抗弯拉强度达1.641 MPa,抗弯拉强度与无侧限抗压强度之比为0.27,冻融循环和干湿循环情况下的无侧限抗压强度均大于5 MPa,抗冻系数大于0.80,水稳系数大于0.88,试件冲刷率为0.139 g/min,质量损失比为1.92%,各项力学性能、耐久性能均满足高速公路和一级公路的要求,说明铁尾矿作为高速公路路面基层材料的主要成分是可行的。     

矿井固壁材料的保温性能研究

针对玻化微珠保温砂浆在矿井内壁应用的局限性,利用单因素实验,并借助各种物理性能测试方法和扫描电镜（SEM）观察,分析了玻化微珠和超细粉煤灰在改善井下固壁砂浆导热性能、强度、耐久性等方面的作用。研究表明,玻化微珠保温轻骨料可有效改善砂浆的导热系数,但同时也会破坏材料的力学性能、耐候性能;超细粉煤灰可以改善材料的导热性、耐久性能以及孔结构,但掺量过多也会显著降低力学性能。保温砂浆的最优配合比是：2%玻化微珠、10%超细粉煤灰、2%可再分散乳胶粉、5%石灰以及1%石膏。     

焙烧尾矿制备透水砖的孔隙特征研究

透水砖作为透水铺装建材,砖体内部孔隙结构直接影响其透水性能,本文重点研究孔隙特征的变化规律.研究以焙烧尾矿、水泥和粉煤灰为胶凝材料,-4.75+2.36 mm粒级尾矿为粗骨料制备透水砖,探究透水砖实测孔隙率数值变化规律,借助光学电子显微镜从微观上分析砖体孔隙结构,并利用Image-Pro Plus软件统计砖体孔隙等效孔径.研究发现,增加焙烧尾矿用量,透水砖实测孔隙率增大,砖体内部孔径增大,透水性能得到提高;增大水胶比和延长振动时间,实测孔隙率逐渐降低,透水砖内部孔径随之减小,影响其透水效果.本研究为优化透水砖的透水性能奠定理论基础,为透水砖的设计及生产提供直接依据.     

双组份巷旁充填材料的配制与性能研究

为了满足巷旁充填材料及时性、高强性以及密封性的要求,文章提出一种双组份巷旁充填材料,其由甲、乙2种干料加水搅拌后等量混合而成,甲料以硅酸盐水泥为基材,乙料以硫铝酸盐水泥为基材。利用正交试验分析了不同配比下材料的物理力学性能,试验结果表明最优水固比为0.8∶1,水泥∶粉煤灰∶膨润土∶河砂的质量比为1∶0.35∶0.20∶0.35时为优化配比。制备出的双组份充填材料凝固速度快,早期强度高,表现出比高水材料更好的力学性能,适合作为沿空留巷巷旁充填材料。     

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。