基于正交试验的全尾砂胶结充填材料配比优化

以某矿山全尾砂为骨料、水泥和粉煤灰为胶凝材料制作胶结充填材料,采用正交试验探讨了料浆质量浓度、灰砂比和掺灰量对充填材料泌水率、7 d和28 d抗压强度的影响程度,并确定了最佳的全尾砂胶结充填材料配比方案。研究结果表明:料浆质量浓度是影响充填料浆泌水率的主要因素,料浆质量浓度为71%和74%时泌水率小于15%可满足工艺要求;灰砂比对充填材料7 d和28 d抗压强度的影响最大,掺灰量次之,料浆质量浓度最小;确定的最佳配比方案为料浆质量浓度74%、灰砂比1∶4、掺灰量10%。     

某金矿充填料浆流变性能及充填体强度的影响研究

料浆的配比对矿山料浆管道输送及充填体的单轴抗压强度有重要影响。以云南某金矿的尾砂作为实验原料,对质量浓度为64%到72%的料浆以及各灰砂比下的充填料浆进行流变实验分析,研究了质量浓度、灰砂比对屈服应力、表观粘度的影响,对不同配比、养护龄期的试件进行单轴抗压强度测试。实验结果表明,质量浓度、水泥掺量对料浆屈服应力和初始表观粘度呈正相关增长,质量浓度越大,对料浆屈服应力和初始表观粘度影响越显著,水泥掺量越多,对屈服应力和初始表观粘度影响越不显著。养护龄期由7d增至14d时,试件单轴抗压强度增幅最高可达200%,由14d增至28d时,最高仅达60%。     

基于 L管实验的全尾砂膏体流变特性研究

膏体的流变特性是影响膏体管道输送的重要因素。为获取膏体充填料浆真实的输送流变特性,利用 L 管实验装置,基于宾汉塑性模型获得膏体料浆的屈服应力及塑性粘度,得到不同料浆浓度和灰砂比条件下的管道输送阻力和充填倍线。结果表明：料浆浓度和灰砂比的上升都会导致剪切应力的增加,充填倍线的降低,其中,料浆浓度是影响充填体流动特性的最关键因素,而灰砂比是影响膏体强度的关键因素,但是膏体浓度的影响也不能忽视。根据 L 管和强度特性实验结果以及一二步骤采场的强度和输送需求,分别推荐了采场最佳膏体配比。     

罗河铁矿全尾砂胶结充填配比优化试验研究

针对罗河铁矿充填料浆浓度波动大,充填料浆灰砂比等关键指标难以控制,并最终影响充填体质量等问题,开展了罗河铁矿全尾砂胶结充填配比优化试验,对充填材料的物理化学性质进行了测定。同时采用全面法试验,对不同质量浓度和不同灰砂比的全尾砂流动性、流变及其强度进行了对比分析,试验结果表明：罗河铁矿全尾砂-74 μm占比达59.87%,属于细粒级尾砂;由于胶固粉中添加了表面活性物质,能够提高料浆的流动性,导致灰砂比越大,料浆的流动性越好;质量浓度为66%~68%时,料浆屈服应力均在100 Pa以内;在满足自流输送和强度要求的前提下,推荐罗河铁矿一步骤充填料浆质量浓度为68%,灰砂比为1∶10,二步骤充填料浆质量浓度为68%,灰砂比为1∶16。     

基于正交设计的某矿超细全尾砂膏体材料配比试验研究

针对我国膏体充填的技术现状,结合某铁矿的生产实践情况,以超细全尾砂、废石与水泥混合制成膏体,运用正交设计的试验方法确定了各影响因素对超细全尾砂膏体各性能指标的影响程度。结果表明:由于超细尾砂的强吸水性,质量浓度对控制膏体塌落度具有主导的控制作用;对于充填体的前期强度(3 d和7 d),抗压强度的影响程度从大到小依次为质量浓度、灰砂比、尾废比,而对于后期强度(28 d)来说,其影响程度从大到小依次为灰砂比、尾废比、质量浓度;确定质量浓度为78%,尾废比为9∶2,灰砂比为1∶25时,膏体的各项性能指标均能达到实际生产和成本控制的要求。此研究可以为同类型的铁矿膏体充填提供一定的理论与技术支持。     

基于管壁切应力的全尾膏体配比确定

管壁切应力的大小反映了管道磨损率的大小,是评价管道输送的重要指标。以料浆浓度、灰砂比、全尾/废石及全尾/库存尾砂为4个影响因素,建立四因素六水平均匀设计试验方案。利用浆式流变仪测定不同配比的膏体流变学参数,并对各水平下的管壁切应力进行回归分析,探讨各因素对管壁切应力的影响及贡献。结果表明:料浆质量浓度对管壁切应力贡献大,敏感性高;废石次之;库存尾砂第三;砂灰比影响最小。最终推荐以下2种充填配合比:浓度80%,砂灰比10,库存尾砂比2%,尾废比4%和浓度79.5%,砂灰比12,库存尾砂比14%,尾废比10%。     

某铁矿胶结充填体特性试验及配比研究

为了找出最适合某铁矿充填料浆的优化配比方案,降低矿山充填成本,保证采空区的稳定性,通过设置不同灰砂比、重量浓度、养护龄期3种参数,对充填体单轴抗压强度、泌水率、固结率、固结比进行测定分析,研究结果表明:影响充填体强度的因素依次为养护龄期、灰砂比、质量浓度。确定最适合该矿山的充填料浆配比方案为灰砂比1∶4,料浆浓度为66%时充填体28d强度为3.48MPa。     

基于深锥底流极限质量分数的全尾砂膏体配比参数优化

为克服全尾砂膏体充填配比未考虑深锥底流极限质量分数的缺陷,基于全面试验设计开展强度试验,对某铅锌矿全尾砂膏体料浆进行配比优化。采用全面试验设计,研究砂灰比、质量分数和养护龄期对全尾砂膏体单轴抗压强度的影响规律,并建立强度预测模型,依据充填体强度要求及深锥底流极限质量分数,对膏体充填料浆进行配比优化。研究结果表明：砂灰比、质量分数和养护龄期是膏体强度的重要影响因素,在4 d、7 d、28 d强度极差分析结果中,均为砂灰比极差大于质量分数极差,方差分析中两者P值均小于0.05,说明砂灰比对强度的影响更为显著;强度与砂灰比呈指数函数降低关系,与质量分数呈二次函数增长关系,与养护龄期呈对数函数增长关系;多元非线性二次多项式回归模型拟合精度较高,相关系数R²均在0.97以上;建立了满足充填体强度要求,以及深锥底流极限质量分数下膏体料浆制备参数的不等式方程组,并求解得出下向进路充填料浆最佳配比范围。     

基于不同养护龄期的充填体强度多元线性回归分析

为探究灰砂比、料浆浓度对充填体强度的影响规律,利用某金矿全尾砂作为原料,制备料浆浓度为65%、67%和69%,灰砂比为1∶4,1∶10和1∶20的胶结充填体试件,开展单轴压缩试验。试验结果表明:全尾砂胶结充填体强度与灰砂比、料浆浓度之间呈多元线性函数关系。养护龄期对充填体强度影响最大,灰砂比次之,料浆浓度最小。充填体强度随养护龄期的增长遵循线性增长规律,且灰砂比和料浆浓度越大,强度随龄期增长速率越大。     

三山岛金矿高质量浓度充填料浆流动特性及管道阻力研究

三山岛金矿西岭矿区由于充填倍线高及料浆质量浓度高,导致料浆输送困难,通过开展流变、L管自流及半工业加压环管试验,对该矿高质量浓度充填料浆流动特性及管道输送阻力进行相关研究.研究结果表明:充填料浆在质量浓度为７４％~７６％,灰砂比为１∶４的条件下达到膏体状态;由 L管自流试验可知,随着料浆质量浓度的增加,料浆屈服应力、塑性黏度及流动阻力明显增加,输送倍线减小,而随着灰砂比的降低,料浆屈服应力降低、塑性黏度增加,但流动阻力降低,导致料浆流速增加,输送倍线增加;充填料浆沿管道的输送阻力与充填料浆屈服应力、塑性黏度、输送流速及输送管道直径有关;通过半工业加压环管试验,管道压力损失与灰砂比、质量浓度和泵送流速均呈正相关,在灰砂比为１∶４、料浆质量浓度为７６％且流速最大(１．５ m/s左右)时管道压力损失最大,直管压力损失为４．３２４Pa/m.     

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。