掺固硫灰水泥胶结磷尾矿充填料浆流变性能

采用跳桌流动度仪和旋转黏度计研究了掺固硫灰水泥胶结磷尾矿充填料浆的流变性能,分析了固硫灰掺量、胶砂比及质量浓度对流变性能的影响。研究表明,掺固硫灰水泥胶结磷尾矿充填料浆的流变曲线符合宾汉塑性流体特征,料浆的触变性很弱。料浆中固硫灰掺量增大时,流动度降低,塑性黏度增大。当胶砂比减小至1∶8或质量浓度高达76%时,固硫灰用量对流动度和塑性黏度的影响程度显著降低。料浆质量浓度为74%时,屈服应力与固硫灰掺量和胶砂比呈正相关。质量浓度高达76%时,固硫灰掺量对屈服应力无显著影响。当料浆胶砂比为1∶5～1∶6,质量浓度为76%时,为保证料浆的顺利泵送应控制固硫灰掺量在40%以内。     

固硫灰基磷尾矿充填体的性能及浸出液水质

采用水玻璃、无水硫酸钠和生石灰共同激发固硫灰活性,制备固硫灰基磷尾矿胶结充填材料。探讨了生石灰掺量对充填体的泌水率、坍落度、抗压强度、变形性能的影响;通过X射线衍射(XRD)和扫描电子显微镜(SEM)研究了充填材料28 d龄期硬化体的微观结构组成及形貌;采用改进的模糊综合评价法对充填体浸出液的水质进行分析评价。结果表明,质量分数为66%,胶砂比1∶1时,当生石灰掺量从5%增至15%时,料浆坍落度减小至160 mm,泌水率几乎全为零,充填材料强度随生石灰用量的增加而明显增大,28 d抗压强度增至5.87 MPa,在干燥环境下的干缩变形明显减小,各项性能指标均满足充填的性能要求;固硫灰在化学激发剂的作用下生成了水化硅酸钙凝胶和钙矾石晶体,充填体浸出液的水质良好,均为Ⅱ、Ⅲ级,对地下水质的影响较小。     

磨细固硫灰渣作为混合材对水泥性能的影响

流化床固硫灰渣含有较高无水石膏和f-CaO,作为水泥混合材利用时会存在体积稳定性问题。在控制固硫灰渣掺量前提下,将固硫灰渣粉磨至不同细度,测试了掺加固硫灰渣的水泥标准稠度需水量、线性膨胀率和胶砂强度,并与普通硅酸盐水泥进行对比。结果表明,提高固硫灰渣细度,特别是固硫灰细度,能使水泥标准稠度需水量减少;固硫灰渣细度提高,水泥凝结时间有所延长;自然养护条件下,固硫灰渣细度变化对水泥收缩没有明显影响,潮湿养护下,磨细固硫灰渣早期能够释放较多膨胀,但处于可控范围;固硫灰渣细度增加,水泥强度明显提高。磨细有利于固硫灰渣作为水泥混合材利用。     

利用钢渣微粉开发鞍钢矿山全尾砂充填胶凝材料研究

针对鞍钢集团冶金工业水淬渣、钢渣、脱硫灰渣以及鞍钢矿山周围的生石灰、水泥熟料和外加剂等激发剂材料,进行满足鞍钢铁矿山阶段嗣后充填法开采替代水泥的全尾砂充填胶凝材料试验研究。探讨了硫酸盐类、碱类、盐类等不同类型激发剂及不同掺量对钢渣活性的激发效果,并研究了水泥熟料掺量、钢渣掺量对全尾砂胶凝材料性能的影响。结果表明,当水泥熟料为12%、脱硫石膏为2%、工业芒硝为1%、钢渣微粉掺量为20%,矿渣微粉为65%时,70%浓度灰砂比1∶6的全尾砂充填体28d强度可达到2.78MPa,满足阶段嗣后充填采矿要求,实现了钢渣废弃物的资源化利用。     

化学激发剂对铜渣粉基胶凝材料性能的影响

为研究化学激发剂对铜渣粉-水泥复合胶凝材料性能的影响,测试了铜渣粉掺量为30％、45％,激发剂掺量为0.5％、1.0％、2.0％时铜渣粉复合水泥胶体的抗压强度,采用抗压强度比定量分析激发剂对铜渣粉复合水泥胶体的激发效果,利用扫描电镜观察激发剂作用下铜渣粉复合水泥胶体水化产物的微观形态.结果表明,随着铜渣粉掺量的增加,水...     

细粒铁尾矿胶结充填体性能试验研究

对金山店铁矿全尾矿进行胶结充填试验,试验采用以工业粉状废料配制的无水泥固结剂L为胶凝材料,细粒铁尾矿为充填骨料。结果表明,与325水泥相比,胶凝材料用量相同时,胶结体单轴抗压强度增加84%以上。此外,考察了三乙醇胺、氯化钠、氯化钙、水玻璃、硫酸钠5种激发剂单掺、复掺时对胶结体抗压强度的影响。结果表明,单掺三乙醇胺的技术经济指标最好,当三乙醇胺掺加量为固结剂的0.05%时,胶结体7d抗压强度增加20%左右。当灰砂比为1∶5.5,三乙醇胺掺加量为固结剂的0.05%时,胶结体7d抗压强度达到1.65 MPa,成本约为33.64元/t尾矿,为细粒铁尾矿井下充填提供了经济适用的技术。     

低水泥高掺量钢渣碱激发混凝土的试验研究

通过改变钢渣粉、矿渣粉等矿物掺合料的比例,研究碱激发大掺量钢渣混凝土的力学性能,并采用X射线衍射和扫描电镜等测试手段对其微结构进行分析。结果表明,激发剂与减水剂、胶凝体系、粗细骨料之间在合理加料、搅拌顺序下,和易性满足要求同时可以制备出钢渣掺量达60%、矿渣掺量为15%、硅灰掺量为5%、水泥掺量仅为20%、强度等级可达C30的混凝土;微观分析表明,优化后的混凝土胶凝体系28 d水化产物结构致密,且孔隙较少,后期强度发展较好。     

复合激发剂对大掺量粉煤灰水泥强度的影响

为解决粉煤灰大宗利用的问题, 研究了复合激发剂对大掺量粉煤灰水泥强度的影响及其水化的机理。结果表明:NaOH、Ca(OH)₂、Na₂SO₄三种激发剂协同激发效果显著, 3 d及28 d抗压、抗折强度均超过42.5水泥强度指标; 最终得到粉煤灰胶凝材料的质量配比为:粉煤灰75%、熟料20%、石膏5%、激发剂3%;对制备的粉煤灰胶凝材料进行凝结时间、胶砂流动度、安定性等物理性能进行测试, 结果均达到粉煤灰水泥的国标要求。研究表明:采用复合激发剂可以提高粉煤灰的胶凝活性, 所制备大掺量粉煤灰水泥可以进行工程实用。      

无水石膏对化学激发固硫灰性能的影响

为抑制循环流化床燃煤固硫灰(简称固硫灰)的有害膨胀,研究了Ⅱ-CaSO_4(无水石膏)含量对化学激发固硫灰强度、体积稳定性的影响,并结合XRD、SEM分析了水化产物和影响机理。结果表明:随Ⅱ-CaSO_4含量增加,NaOH激发固硫灰抗折、抗压强度均先增大后减小,Na_2Si O_3、Na_2CO_3激发固硫灰的抗压强度减小,抗折强度分别呈现出先增后降、降低的整体变化趋势。标准养护下,3种激发体系硬化体的线性膨胀率均随Ⅱ-CaSO_4的增加而增大;3种激发剂中Na_2SiO_3对抑制固硫灰有害膨胀最有效。采用X射线衍射(XRD)、扫描电镜(SEM)对化学激发固硫灰水化产物进行了分析,结果表明,NaOH激发固硫灰体积膨胀主要由水化产物钙矾石引起,Na_2SiO_3激发固硫灰无钙矾石生成,硬化体膨胀主要由水化硅酸钙(C-S-H)吸水膨胀引起,Na_2CO_3激发固硫灰体积膨胀由水化产物钙矾石或碳硫硅钙石引起。     

固硫灰基地聚合物固化含铬污泥

在研究水玻璃模数、水玻璃添加量、偏高岭土掺量对固硫灰基地聚合物抗压强度影响的基础上,进一步探讨了固硫灰基地聚合物固化含铬污泥的性能及机制。固硫灰制备地聚合物的优化实验参数为：水玻璃模数M为2.5,水玻璃掺比为33.3%,偏高岭土掺比为20%。含铬污泥最大固化量为52%,固化体28 d抗压强度达到6.5 MPa,总铬及Cr(VI)浸出量分别为0.37 mg/L和5.93×10-3 mg/L,远低于GB 5085.3-2007标准限值。XRD和SEM/EDS分析表明含铬污泥及其固化体均为无定形态,污泥中的铬可能以物理包裹的形式被固化于地聚合物凝胶相中。IR分析表明铬元素可能通过化学键的形式进入地聚合物的三维网络结构实现固化。     

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。