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。     

粉煤灰转相焙烧过程铝硅碱溶活性探究

粉煤灰主要成分为氧化铝和二氧化硅,其铝硅比较低,传统拜耳法难以实现铝硅分离,在碱性体系下需对粉煤灰中的铝、硅组元进行改性与处理,提高其中铝、硅组元的碱溶活性差异,从而实现铝硅分离的目的。以内蒙古某地区高铝粉煤灰为研究对象,通过硫酸固相转化手段将铝硅酸盐解离,解离后的铝、硅组元混合相通过转相焙烧的方式进行碱溶活性调控,以实现铝、硅组元碱溶初步分离的目的。结果表明,随着焙烧温度的升高,焙砂中的非晶态氧化铝有向过渡相氧化铝转变的趋势,碱溶活性逐渐降低,非晶态二氧化硅的结构未有明显变化趋势,其碱溶活性也未发生明显变化;在焙烧温度950℃、焙烧时间60min条件下和碱溶温度95℃、时间30min、Na_2O浓度38.75g/L、液固比10∶1的溶出条件下,二氧化硅溶出率达到73%以上,氧化铝溶出率不到2%。     

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%。     

KOH低温焙烧钾长石提取SiO2

以钾长石为原料,氢氧化钾为助熔剂,采用焙烧法破坏钾长石结构,使矿石中的不溶性硅转化成可溶性硅。采用水溶工艺溶出焙烧熟料中的硅。研究了工艺参数即焙烧温度、焙烧时间和碱矿比对SiO2溶出率的影响。结果表明,碱矿比对SiO2的溶出率影响最大,并得到最佳焙烧条件为:焙烧温度500℃、焙烧时间2.5h、碱矿比2.5。在此条件下,SiO2的溶出率可高达99.5%。     

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。     

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。     

还原焙烧赤泥-综合回收铁铝研究

通过单因素试验系统研究了还原焙烧赤泥过程中各因素对铁铝回收效果的影响。结果表明, 控制配碳质量比15%, 在焙烧温度800 ℃、钙硅比2.6、碱比1.5条件下焙烧60 min, 通过氢氧化钠调整液浸出铝和磁选回收铁, 铝溶出率达到83.8%, 铁回收率在95.0%以上, 铁精矿品位62.0%左右。磁选尾矿钪含量约为200 g/t, 满足工业利用要求。     

湿法处理钠硅渣回收氧化铝工艺研究

对钠硅渣脱碱后的水化石榴石通入CO₂气体转型的反应进行了热力学分析, 研究了温度、时间、改性次数、Na₂CO₃浓度对转型效果的影响, 并且研究了转型后渣溶铝过程中, 苛性碱浓度、温度、液固比、反应时间对氧化铝溶出率的影响。结果表明: 钠硅渣脱碱后形成的水化石榴石能被CO₂分解, 在分解过程中硅化合物易形成CaO·SiO₂·H₂O、6CaO·6SiO₂·H₂O。反应时间的延长, 适当的反应温度, 有利于提高水化石榴石的转化率, 同时改性处理也可以提高转化率。在溶铝过程中, 时间延长, 液固比提高, 碱浓度升高, 以及适宜的反应温度均可提高溶铝效率。试验最佳工艺条件为: 转型最佳工艺为时间2 h, 液固比5～10, 温度50 ℃, 改性一次; 溶铝最佳工艺为温度50 ℃, 液固比为10, 时间1 h, 碱浓度大于50 g/L, 最优条件下氧化铝溶出率达60%以上, 弃渣中铝硅比A/S小于0.6。     

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％,Fe2 O3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...     

不同焙烧法对煤矸石中铝浸出效果的影响

煤矸石中铝的溶解性质不仅受焙烧温度的影响,与焙烧方式也密切相关。通过X衍射分析研究了直接焙烧时,煤矸石中矿物成分的变化以及温度对主要含铝矿高岭石物相转化的影响,结合铝的溶出试验,确定在700℃焙烧,用氢氧化钠碱液可将煤矸石中95%以上的铝溶出。采用石灰石法时,铝的溶出效果受焙烧温度和石灰石与煤矸石的配比影响。在较低的温度即600℃,当石灰石与煤矸石配比在2.06时,铝的溶出率也可达90%以上,在温度为900℃,当石灰石与煤矸石配比大于理论计算值时,铝的利用率可达99%。     

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     

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     

2014 second batch of rare earth quota released

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China rare earth market review

正November 21~30,2014Due to weak demand from downstream industries,transactions of rare earth in Chinese domestic market were inactive.It was difficult to sell any rare earth products except for dysprosium oxide and terbium oxide.Suppliers lost confidence in recent market.Demand for rare earth products was soft.Consumers continued to take a wait-and-see attitude.Rare earth export market remained slow.     

Galaxy Magnets achieved the net profit of 34.02 million yuan in the first six months of 2014

正Galaxy Magnet announced its financial results for the first half of 2014 on August 14.For the first six months ended on 30 June 2014,Galaxy Magnet achieved operation income of RMB 182.3 million,up8.40% over the same period of 2013,and the net profit attributable to the shareholders of the listed company of 34.02 million yuan,increasing 35.49% over the same period of last year.Stable performance increase was led by development of new customers and application market of magnets.     

Rare Earth Application in Steel in China

<正>China has rich rare earth resources.Output of rare earth and steel in China ranks the top first in the world.However,there is still certain distance between the steel produced in China and developed countries from the point of varieties and quality.China still has to import some types of steel.Improving the quality should be emphasiZed in future development of steel industry in China.Rare earth can be used to upgrade traditional steel     

Current situation and future trend of China rare earth luminescent materialindustry(continued)

<正>Developing ecological lighting source The world is facing the big problem of energy shortage today and the contradiction between economy development and environmental protection is worsened.Therefore,people are more likely to choose an ecological light source that is more energy efficient and environmental friendly.The choice provides great opportunity for the development of rare earth optical material industry in China.The concept of green lighting positions rare earth luminescent material as a leading player in illumination market.The light source of both rare earth luminescent lamp and LED lamp is ecological and energy saving.This is why     

稀散金属产业的观察与思考

分析了近年来国内外稀散金属产业的生产、应用、资源与市场状况.铟锡氧化物靶材、砷化镓晶片、锗红外材料、铼高温合金和硒在电解锰及玻璃的应用等已成为稀散金属的主要应用领域.稀散金属的产量快速增长达到历史高位而导致了市场的失衡.以GaInP_2/GaAs/Ge,CIGS和CdTe为代表的非硅系太阳能电池是稀散金属的新兴应用领域,将给稀散金属带来日益增长的需求.