深井开采工作面通风与降温技术研究

对国内外深热矿井掘进工作面通风与降温技术进行了理论分析与研究，结合冬瓜山铜矿的具体开采条件，确定了掘进工作面强化通风与降温实施方案。     

掘进巷道强化通风与射流通风流场的试验研究

针对冬瓜山铜矿掘进工作面通风和降温要求,进行了掘进巷道强化通风设计和现场试验。现场试验表明,强化通风缩短了排炮烟的时间,提高了工作效率,使作业环境明显改善。研究还表明当巷道的宽高比越大,更有利于工作面通风。局扇通风试验的污风再循环系数R为0.366,表明局扇通风排炮烟效果较好。     

阳城煤矿掘进工作面强化通风降温研究与应用

分析了阳城煤矿热源情况,提出了以加强通风降温为主的降温措施,进行了掘进工作面强化通风设计和现场实验,工作面的气温从32℃降低到29℃,使作业环境明显改善。     

掘进巷道双风筒降温措施的研究

在非人工制冷降温的掘进工作面,利用双风筒供风是降低工作面风流温度的一个有效措施。根据风筒内、外内流相互制约的特点,分析了双风筒布置掘进巷道内的风流热力变化,并提出了计算方法和原理,依此编 制了计算机程序。利用该计算机程序分析了掘进工作面风筒内、外风流温度的变化规律,为高温掘进工作面的热源计算和通风降温提供了可靠的计算工具。     

掘进巷道通风降温试验研究

为了得到不同通风条件下掘进巷道内的气温变化影响规律,在蚕庄金矿徐家瞳-750 m水平进行了有无人员作业、通风机是否工作、不同风量等条件下的通风降温试验研究。研究结果表明:通风6 min时气温迅速降低,12min后气温虽然降低但降温梯度大幅减小,在停风60 min时巷内气温迅速升至28℃左右,为保证工作面满足安全规程要求,有人员作业地点要保持连续通风;气温随风量的增加而降低,且距离出风口越远时气温越高,可适当加大工作面风量;巷内岩壁温度随通风时间的增加下降很小,但同一位置岩壁温度与气温温差在加大,且通风60 min后温差可达3℃以上;风筒每增加10 m,出口气温增加约1℃,实际生产中需要考虑风筒保温问题。试验得出的掘进巷道气温变化规律可为其他水平和条件下的通风降温参数设置提供参考。     

掘进工作面通风除尘系统

<正>中国煤炭科工集团太原研究院和德国CFT公司联合研发的掘进工作面通风除尘系统,适用于煤矿掘进机掘进的巷道,与压入式通风系统配套使用。该系统使用了附壁风筒和高压湿式除尘器,具有很高的集尘和除尘效率,总除尘率达99.4%以上,能很好地保障操作人员健康。掘进工作面通风除尘系统主要特点是使用长压短抽的混合通风除尘方式,在掘进工作面压入式通风风筒上,     

掘进工作面射流通风流场研究

掘进工作面压入式通风实际上是有限空间的受限贴附射流通风． 根据流体力学和射流理论, 分析了掘进通风射流产生过程及掘进工作面压入式通风风流结构． 风流从圆形风筒射入掘进工作面形成射流区和回流区． 给出了回流区平均速度、最大回流速度及射流作用距离的计算模型, 为掘进工作面合理有效通风提供了新的理论依据．     

掘进工作面换热模拟研究

根据掘进工作面通风和换热特点,以掘进工作面冲击射流换热系数的影响因素关联式为基础,采用ANSYS软件,对特定巷道(中煤科工集团重庆研究院粉尘通风防灭火试验巷道,D已确定)不同风流雷诺数Re、风筒直径d、风筒出口距迎头断面的距离H以及边界围岩处于恒壁温条件下等840种组合情况进行了模拟。得出了掘进工作面冲击射流换热系数影响因素关联式的具体形式,其相关系数R2为0.937,可为矿井降温中围岩热源散热量的计算提供理论基础。     

掘进作业面压入式通风温度场数值模拟

依据空气动力学、流体力学和传热学等相关理论并结合矿山实例,利用Fluent模拟软件分别在单风筒、双风筒两种不同压入式通风方式下,对巷道内的温度场在多种送风风速、风温情况下的分布规律进行数值模拟研究。结果表明,双风筒压入式通风较单一压入式通风更优,并且距离掘进面较远部分的巷道低温区更广,风温低于28℃的区域占2/3;同时在掘进面附近,双风筒压入式要比单风筒压入式温度低1℃~2℃,风流分布更均匀;入口风速能影响巷道内温度场分布,当巷道风速超过0.5 m/s,其降温效果不再明显;掘进面的温度会随着入口风流温度的降低而逐渐下降,且两者呈很强相关性。     

独头巷道氡的析出特性与排氡通风

本文论述了独头巷道通风排氡的效果。采用压入式通风时,风筒口距工作面在10米以内较适宜。掘进工作开始前利用风筒对工作面进行负压通风能使巷头区(指风筒口至工作面之间的空间)氡浓度降低。对风源浓度(指在负压通风条件下巷道的新鲜空气中含氡及其子体的浓度)的合理值提出一个指标,有助于检验井下通风效果。认为增加工作面的进风量和降低风源浓度值是降低工作面氡浓度(稳态值)的两大措施。     

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

正~~     

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