铝土矿反浮选体系分散与凝聚理论

在铝土矿反浮选脱硅过程中,矿浆悬浮液的分散和凝聚状态对微细粒－水硬铝石的回收和精矿铝硅比有显著影响。要使各种硅酸盐矿物混合物达到有效的选择性分离,首先必需使矿浆悬浮液处于最佳分散状态,避免各种矿物细粒间的相互混杂和矿泥罩盖。针对高硅铝土矿反浮选脱硅过程,根据经典DLVO理论,从颗粒间的相互作用分析了微细粒－水硬铝石在各种含硅脉石矿物表面的粘附情况。结果表明：一水硬铝石与含硅脉石矿物颗粒间的范德化相互作用总是吸引;而它们间的静电相互作用在弱碱性条件下时为排斥,在弱酸性条件下时为吸引,一水硬铝石的夹带上浮较为严重,不利于铝土矿的反浮选。     

异丁黄药用于高硫铝土矿浮选除硫的研究

鉴于我国铝土矿保有量有限,高品位铝土矿由于掠夺性开采而面临枯竭,具有高品位的高硫铝土矿将是今后氧化铝生产的主要矿物原料。而高硫铝土矿脱硫,是该类型铝土矿能否工业应用的关键。本试验采用单因素实验,研究了高硫铝土矿在浮选剂异丁黄药作为捕搜剂,松油醇为起泡剂进行高硫铝土矿反浮选除硫的工艺条件。重点考察了浮选剂用量、浮选时间、浮选矿浆浓度、pH值及矿石粒度对浮选的影响,得出了反浮选除硫的适宜工艺条件。研究表明,在适宜工艺条件下,异丁黄药浮选除硫后的尾矿中,硫含量由原矿2.08%达到15.1%,精矿中硫含量降为0.62%,达到工业生产氧化铝的要求(0.7%)。氧化铝回收率为92.3%。在弱碱性条件下,异丁黄药的捕搜性能在硫酸铜活化下有很大提高。浮选动力学研究表明,异丁黄药对硫化矿的浮选符合Langmuir的化学吸附原理。     

Intensifying digestion of diaspore and separation of alumina and silica

1　INTRODUCTIONDespitetheabundantdepositofbauxitesinChi na ,ofthosepredominantisthediasporictypewithhighalumina ,highsilicaandlowferricoxides .Thebauxitedeposit,withthemassratioofaluminatosil ica(A/S)between 4and 8,accountsfor 80 %ofallthebauxitedeposit.Thenatureofhighsilicacontentdeterminesthatthemainlyadoptedtechniquetopro ducealuminainChinashouldbeBayer sinteringcom binationprocessorevenpuresinteringprocess .Althoughadramaticadvancementinaluminaproductionhasbeenachievedandthetechnolo…     

Optimization of grinding in reverse flotation for bauxite

1　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｂａｕｘｉｔｅｉｓｔｈｅｉｍｐｏｒｔａｎｔｍａｔｅｒｉａｌｆｏｒａｌｕ ｍｉｎｕｍｉｎｄｕｓｔｒｙａｎｄｒｅｆｒａｃｔｏｒｙｉｎｄｕｓｔｒｙ .Ｂａｕｘｉｔｅｒｅ ｓｏｕｒｃｅｓｉｎＣｈｉｎａａｒｅｒｉｃｈ[1] .Ｔｈｅｅｘｐｌｏｒｅｄｒｅｓｅｒｖｅｓａｒｅ 2 .3ｂｉｌｌｉｏｎｔｏｎｓ .Ｈｏｗｅｖｅｒ ,ｍｏｓｔｏｆｔｈｅｍａｒｅｈｉｇｈａｌｕｍｉｎａａｎｄｈｉｇｈｓｉｌｉｃｏｎｄｉａｓｐｏｒｉｃｂａｕｘｉｔｅａｎｄｔｈｅｒａ ｔｉｏｏｆａｌｕｍｉｎｕｍｔｏｓｉｌｉｃｏｎｉ…     

中国拜耳法氧化铝生产技术的发展方向

应用一水硬铝石型铝生产溶出动力学及一水硬铝石型铝土矿中硅钛矿物的反应行为规律对现有的间接加强化溶出技术进行了技术上的剖析。认为现有的单流法溶出技术用于处理我国的一水硬铝石型铝土矿,都表现有某些方面的不足。我国自行开发成功的高温双流水溶出技术实现一水硬铝石矿间接加热强化溶出的适宜选择。     

Effect of hydroxamic acid starch on reverse flotation desilicate from diasporic bauxite

It is important to depress diaspore effectively in order to remove silicates from diasporic bauxite.A new water soluble polymer hydroxamic acid starch(HA-starch)was prepared.The effects of the product on the diaspore and kaolinite flotation were investigated and its reactive mechanism was studied by zeta potential measurement and FTIR.The results show that HA-starch can depress diaspore while make positive effect on kaolinite flotation at low pH value(pH below 6)The flotation recovery of diaspore was sharply decreased with the increase of concentration of HA-starch.The chemical adsorption of HA-starch on the surface of diaspore was revealed.     

Technology and mechanism of desilication from roasted diasporic bauxite in atmosphere

The leaching desilication technology of roasted diasporic bauxite in atmosphere by caustic soda solution was investigated. The optimum parameters were: the grinding fineness of the roasted bauxite -0. 076 mm and 80 % -85 %,leaching time 2h, Na2Ok100-150g/L, L/S 4-5, leaching temperature 90-95℃. The desilication rate 55.20% and concentrate A/S (mass ratio of A12O3 to SiO2) 9.90, as good as those obtained at pressure, were obtained respectivdy.Investigation of two-stage leaching shows that it can both improve desilication rate of roasted ore and reduce leaching time.When time of the first stage and the second stage is 30 min and 30 min respectively, desilication rate can reach 59.65 %.X-ray diffraction analysis of the concentrate has proved that desilication procedure is accompanied with the formation of sodium aluminosilicate hydrate. X-ray spectra also show that silica removed during leaching is amorphous silica. SiO2 occurrina as ouartz in raw ore or mullite formed during roasting can not dissolve in alkali solution.     

铝土矿中铝硅矿物晶体结构的综述

详细论述了国内外铝土矿资源中几种主要矿物的晶体结构特征,讨论了三种铝矿物之间及与硅矿物晶体结构之间的差异,及在磨矿过程中的解离特性,为铝土矿的浮选提供基础资料。     

我国的铝土矿资源和高效低耗的氧化铝生产技术

分析了我国一水硬铝石型铝土矿资源的特点及其对氧化铝生产工艺流程、能耗和成本的影响,论述了为实现我国氧化铝工业可持续发展,高效低耗地开发利用我国中低品位一水硬铝石矿资源的技术路线,提出了采用选矿拜耳法、石灰拜耳法、新并联法和串联法等新技术改进现有的拜耳法和联合法氧化铝生产工艺以及亟待开发的节能降耗和提高质量的重大新工艺和关键技术.     

变性淀粉在铝硅矿物浮选分离中的作用机理

通过浮选实验、动电位和红外光谱测定,详细考察了变性淀粉在铝硅矿物浮选分离中的作用效果和机理。浮选实验显示：非离子淀粉和阴离子淀粉在pH＜6时,抑制一水硬铝石的浮选,但当pH＞6时,却对一水硬铝石浮选有活化作用;阳离子淀粉在较宽pH值范围内对一水硬铝石均有抑制作用;3种淀粉化合物在pH＜6时均活化高岭石的浮选,当pH＞6时活化作用较微。结果表明：变性淀粉是一水硬铝石型铝土矿反浮选中实现一水硬铝石和高岭石分离的有效调整剂,阴离子淀粉使矿物表面ζ电位更负,阳离子淀粉使矿物质表面ζ电位更正,非离子淀粉使矿物表面电位绝对值减小。由实验结果结合药剂与矿物作用前后的红外光谱分析,得出结论：非离子淀粉主要通过氢键作用吸附于矿物表面,而静电力和化学键合力在阴离子淀粉和阳离子淀粉吸附中发挥着重要作用。     

影响一水硬铝石型铝土矿溶出的因素比较分析

一水硬铝石型土矿因其矿物特点,对溶出条件要求苛刻,本文对影响铝土矿溶出的主要因素进行了比较分析,并从动力学及化学反应机遇上分析了各因素对铝土矿溶出工艺的影响,为改造生产工艺及提高溶出效果提供参考。     

Aluminum-silicates flotation with quaternary ammonium salts

1　INTRODUCTIONThediasporic bauxiteinChinaisdifferentfromthegibbsite bauxiteandboehmite bauxiteinothercountriesbyitshighcontentofAl2 O3andSiO2 andlowmassratioofAl2 O3toSiO2 (massratioofAl2 O3toSiO2 =A/S ,usually5 6 ) .Theproductioncostofa luminumoxidefromsuchrefractorybauxiteby“sin tering”or“combining”technologiesismuchhigherthanthatbyBayer sprocess .Sothatthealuminum silicateganguessuchaspyrophyllite ,illiteandkaolin iteinthebauxiteisneededtoberemovedtoincreaseA/S .Hussainetal…     

Temperature dependence of crystal structure and digestibility of roasted diaspore

Through X-ray diffraction patterns and scanning electronic micrographs, temperature dependence of the crystal structure of roasted diasporic bauxite at different temperatures and the digestibility of roasting production were investigated systematically. The lattice parameters of unit cell for chemically purified diaspore and unequilibrium alumina-contained oxide obtained from the diaspore roasted at different temperatures were determined. It is found that, with roasting temperature increasing, the roasting production changes from the original dense and perfect diaspore crystal into imperfect corundum with many microcracks and small pores on its surface and then into perfect corundum with low digestibility. The optimum roasting temperature with best digestibility is approximately 525℃ when residence time is about 25min. It is thought that the change of crystal structure, formation of microcracks and small pores in the temperature field are the main essential reasons for improving digestibility of diasporic bauxite and its roasting production.     

对我国铝土矿资源和氧化铝工业发展的认识

本文从我国氧化铝工业的发展和碱耗、能耗、成本的大幅度降低，分析论证了一水硬铝石原料的优势和劣势，得出了平果型矿石是优质资源，其它矿通过选矿经济脱硅石也可成为优质资源，因而采用拜耳法和选矿拜耳法是我国氧化铝工业技术发展的方向。     

Synthesis of N-decyl-1,3-diaminopropanes and its flotation propertieson aluminium silicate minerals

1　INTRODUCTIONBauxiteisamajorsourceforaluminaproduction .Bayerprocessfeaturesshortresidencetime ,lowener gyconsumptionandhigh qualityproduct .Asare sult ,itiswidelyusedtotreatthebauxiteofalu minum/silicateratio (A/S)morethan 8.AlthoughthereareabundantaluminiumoxidemineralresourcesinChina ,mostofthemarediasporicbauxitewithhighaluminumcontent ,butlowA/Sratio .Among4 0bauxitediggings ,theaverageAl2 O3andSiO2 con tentsare 6 3.4 1%and 11.5 9% ,respectively ,whiletheaverageA/Sratiois4 6 […     

氧化铝生产新工艺、新技术的开发与应用

介绍了我国处理高硅难溶铝土矿的新工艺、新技术及工程实例。提出了今后优化氧化铝工艺的研究方向。     

双流法预热条件下铝土矿浆中杂质矿物的反应行为

对我国两个主要矿区的铝土矿进行了双流法预热条件下矿浆中含硅矿物及含钛矿物反应行为的实验研究,考察了矿浆固含不同时含硅和含钛矿物反应行为的变化.在较长的预脱硅时间条件下,随着矿浆固含的增加,预脱硅效率及矿浆液相中的SiO2浓度呈下降的趋势.在矿浆预热过程中,脱硅效率随着矿浆固含的增加而增加,当固含增加到一定程度时,脱硅效率反而下降,脱钛效率随矿浆固含的变化规律和脱硅效率相同;矿浆液相中的SiO2浓度随矿浆固含的增加而下降.在双流法预热条件下,矿浆固含越高,矿浆预热过程中含硅矿物、含钛矿物及含镁矿物的结疤速率越低.     

捕收剂RL在铝土矿浮选中的应用

研究了一水硬铝石、高岭石及叶腊石等单矿物在RL为捕收剂时的浮选特性,考察了各种调整剂、难免离子对浮选体系的影响,在此基础上进行了人工混合矿和实际矿石的分离试验。实际矿石闭路试验结果表明：采用RL为捕收剂,碳酸钠和六偏磷酸钠为调整剂,精矿中Al2O3和SiO2的品位分别为70．74％和6．37％（精矿铝硅比为11．11）,Al2O3的回收率达到90．52％。     

Transformation of hematite in diasporic bauxite during reductive Bayer digestion and recovery of iron

The reductive Bayer digestion by using iron powder as reductant is proposed to convert hematite to magnetite and further to dissociate iron minerals from sodium aluminosilicate hydrate (desilication product, DSP) based on the differences of their surface properties. The results show that the differences of surface properties between magnetite and DSP in zeta potential, wettability and solvation trend facilitate magnetite to agglomerate, grow up and thus to dissociate from DSP. The increments of reductant amount and alkali concentration favor the transformation of hematite in digestion with the relative alumina recovery of 98.91%. Processing the resultant red mud can obtain qualified iron concentrate with iron grade of approximate 60% and recovery of about 86% through magnetic separation, resulting in reduction of red mud emission higher than 70%. The results are potential to develop a novel technology for processing high iron diasporic bauxite efficiently and provide references for comprehensive utilization of high iron red mud.     

Efficient separation of alumina and silica in reduction-roasted kaolin by alkali leaching

Alkali leaching was employed to investigate the separation of alumina and silica in roasted kaolin obtained by roasting kaolin alone in air at 1273 K for 60 min and in clinker prepared by roasting the mixed raw meal of kaolin, ferric oxide and coal powder with Fe₂O₃/Al₂O₃/C molar ratio of 1.2:2.0:1.2 in reducing atmosphere at 1373 K for 60 min. The thermodynamic analyses and alkali leaching results show that the composition of the Al?Si spinel in roasted kaolin is close to that of 3Al₂O₃·2SiO₂ and the spinel is dissolved with increasing leaching time, resulting in difficulty in deeply separating alumina and silica in kaolin by the traditional roasting?leaching process. On the contrary, the efficient separation of alumina and silica in kaolin can be reached by fully converting kaolinite into insoluble hercynite and soluble free silica, namely quartz solid solution and cristobalite solid solution, during reduction roasting, followed by alkali leaching of the obtained clinker. Furthermore, experimental results from treating high-silica diasporic bauxite indicate that the reduction roasting?alkali leaching process is potential to separate silica and alumina in aluminosilicates.