高硅铝土矿溶出脱硅试验研究

为了脱去铝土矿中的含硅矿物提高铝硅比,将原矿石在1180℃的温度下利用电炉焙烧半小时,然后再在低压釜中溶出,溶出温度为120℃、溶出时间为15 min、液固比为10:1、碱液浓度40%。经过焙烧的矿石二氧化硅溶出率最高可达42%,可将矿石铝硅比从2.52提高到5.03。     

白泥硫酸法制取白炭黑的工艺研究

白泥是粉煤灰"一步酸溶法"提取氧化铝后产生的高硅尾渣,由于其具有颗粒小、活性高、二氧化硅含量高和其它杂质含量少的优点,是制备硅基材料的优质原料。文章研究了硫酸法去除白泥中的氧化铝时,焙烧工艺及溶出工艺条件对其影响。结果表明,焙烧温度320℃,焙烧时间120 min,焙烧酸泥质量比为0.9,溶出温度150℃,溶出时间120 min,溶出酸泥质量比为3,酸浓度5%时,白泥中铝元素去除率达95.6%,二氧化硅提取率达到90%,且获得的样品白炭黑中硅含量达到90%。     

氟化钾助溶法对粉煤灰中氧化铝溶出率的影响研究

针对传统工艺从煤粉炉粉煤灰中提取氧化铝提取率低的问题,采用了以KF·2H2O为焙烧助溶剂的方法,从粉煤灰中酸溶氧化铝,粉煤灰中氧化铝的溶出率可达95%以上。研究了焙烧配比、焙烧温度、溶出固液比、溶出温度、溶出时间等对粉煤灰中氧化铝溶出率的影响,并用XRD对烧结样品和酸浸渣进行了表征。研究结果表明,氟化钾助溶法对煤粉炉粉煤灰中的氧化铝活化效果明显,活化后主要相态为霞石,在焙烧配比为20∶19、焙烧温度为900℃、焙烧时间为1 h的最佳活化条件下及6 mol/L HCl、1/4的固液比、60℃溶出30 min的最佳溶出条件下,粉煤灰中氧化铝的溶出率达97%以上,且氟最终主要在酸浸渣里。     

高硅铝土矿焙烧-碱浸脱硅及热力学研究

为有效解决中低品位高硅铝土矿脱硅及矿石溶出性能。采用焙烧碱浸脱硅技术方案,考察焙烧温度、焙烧时间、焙烧矿石粒度对脱硅效果的影响。研究结果表明：最佳焙烧脱硅条件为温度950℃、时间60S、矿石粒度150μm。焙烧过程中含硅物相转变为无定型二氧化硅,碱浸过程中氧化铝、二氧化硅同存时优先生成NaAl2(AlSi3O10)(OH)2。在最佳脱硅条件下矿石脱硅率为47.12%,相比原矿、焙烧矿精矿溶出率提高并达到97.68%。     

碱溶粉煤灰提硅工艺条件的优化

采用正交实验对碱溶粉煤灰提取二氧化硅的最佳工艺条件进行了优化,结果表明:碱溶粉煤灰提取硅的条件为:反应温度130℃、NaOH初始浓度17.5mol/L、液固比1.5∶1、反应时间6m in。在此条件下,过200目筛的粉煤灰提硅率可达75.65%,提硅渣中的铝硅比达到3。     

铝土矿焙烧-碱浸脱硅新工艺

针对中、低铝硅比的一水硬铝石－高岭石型铝土矿，进行了回转窑焙烧和常压碱浸脱硅试验研究，结果表明：该工艺是可行的，其焙烧工艺条件为：焙烧温度1050－1100℃，焙烧时间15－20min；常压碱浸脱硅工艺条件为：Na2Ok浓度为100－150g/L，液固比4－5的条件下，溶出温度为90℃左右，溶出时间为2h。此时脱硅率达55．20％，精矿铝硅比（A／S）为9．9，与加压溶出条件下取得的脱硅效果相当。而采用两段溶出脱硅能够提高焙烧矿的脱硅率，显缩短溶出时间：当第一、二段溶出时间均为30min时，焙烧矿的脱硅率可达59．65％。高压拜耳法溶出试验表明：经过焙烧脱硅得到的铝精矿的脱硅率比原矿高。     

赤泥与高硫铝土矿协同焙烧回收氧化铝

以固体危废物拜耳法赤泥和难处理的高硫铝土矿作为原料,进行碱法焙烧回收氧化铝的工艺的探讨,通过热力学数据库,考察焙烧温度、碱溶出过程中参数对氧化铝溶出率的影响。研究结果表明：焙烧的温度对氧化铝的溶出的影响最大,焙烧过程产生不溶性盐和物料高温下收缩形核,均降低氧化铝的回收率,在最佳焙烧温度1100 ℃下碱法焙烧,氧化铝的最佳溶出条件：溶出温度为80 ℃、溶出时间为25 min、液固比为10 mL/g、NaOH浓度为18 g/L、Na₂CO₃溶度为8 g/L。在此条件下,物料中氧化铝的溶出率可达92.16%,溶出渣通过磁选回收铁,剩余的非磁性物质作为耐火材料。     

硫铁矿尾矿活化焙烧-二次碱浸脱硅制备铝精矿

这是一篇冶金工程领域的论文。西南某地区硫铁矿选硫尾矿中的氧化铝含量高于46%,具有较高回收利用价值,但尾矿中的铝硅酸盐矿物中存在含量较高且晶体结构稳定的SiO₂,导致尾矿的铝硅比(A/S)较低,仅为1.72。为了实现铝硅分离,制得铝精矿以回收利用该尾矿,通过活化焙烧使其中结构稳定的SiO₂转变为非晶态SiO₂,再使用NaOH溶液二次浸出焙砂脱硅制备得到铝精矿。结果表明：在焙烧时间35 min,焙烧温度1140℃,一次碱浸NaOH浓度140 g/L,浸出温度110℃,浸出时间30 min,浸出液固比16的适宜条件下,铝硅比(A/S)提高到4.11;在二次碱浸NaOH浓度140 g/L、浸出温度110℃、浸出时间30 min、浸出液固比10的较佳条件下,得到铝硅比(A/S)为5.11的铝精矿,为该尾矿的综合利用打下了良好的基础。     

低品位高硅铝土矿静态焙烧溶出

针对低品位高硅铝土矿溶出性能差,本文采用低温静态焙烧溶出工艺,考查焙烧温度、焙烧时间及矿石粒径对氧化铝溶出效果的影响。其结果表明：矿石含铝主要物相为一水软铝石、一水硬铝,其在焙烧过程中分解温度为515℃。经过焙烧后,矿石结构变为疏松孔洞及沟壑结构。在焙烧温度600℃、焙烧时间90 s、矿石粒径150μm条件下,氧化铝相对溶出率最优,较原矿提高7.57%达到了97.88%。焙烧矿氧化铝溶出限制性环节为内扩散,其表观活化能为44.72 kJ/mol。     

常压溶出低铝硅比高铁铝土矿试验研究

针对广西某地极低铝硅比高铁三水铝土石铝土矿的特性,在常压条件下,对其进行了溶出试验研究。该矿Al2O3含量只有44%,Fe2O3含量达到19.13%,铝硅比只有3.97。研究了溶出温度、溶出时间、溶出苛性比值和溶出碱浓度对氧化铝溶出率的影响。结果表明:最佳溶出条件为溶出温度105℃;溶出时间45min;溶出苛性比值1.80;溶出碱浓度180 g/L。在最佳条件下,氧化铝溶出率达到81.68%,赤泥中铝硅比仅为0.74。该工艺与常规的溶出工艺相比,实现了在常压条件下溶出,且溶出率高,大大减化了生产工艺,极大地降低了生产成本,取得了较为理想的结果。     

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。