CAJ | 학술논문

提出热活化脱硅技术处理某煤系硫铁矿浮选尾矿制备铝精矿，对制备氧化铝精矿的工艺制度及脱硅机理进行研究。结果表明：该尾矿适宜的热化学活化脱硅制度为活化焙烧温度1150℃、焙烧时间15~20 min、碱浸溶硅温度125~140℃、溶出时间30 min、NaOH浓度140 g/L。在此条件下，对Al 2 O 3和SiO 2含量分别为46.22%和28.33%(质量分数)的硫铁矿浮选尾矿，焙砂SiO 2溶出率达到71.91%，所得铝精矿中Al 2 O 3含量达69.29%，铝硅比5.59。XRD结果表明：硫铁矿尾矿中伊利-蒙脱石、高岭石和叶腊石等铝硅酸矿物在焙烧过程中活化分解生成无定形SiO 2和少量莫来石，与此同时，一水硬铝石转变成α-Al 2 O 3。在焙砂的碱浸过程中，无定形SiO 2溶解于NaOH溶液被脱除，而α-Al2O3和莫来石不能溶解，同时生成的水合铝硅酸钠(Na8Al6Si6O24(OH)2(H2O)2)将导致SiO2溶出率降低。焙烧过程中尾矿中的黄铁矿转化为赤铁矿、锐钛矿部分转化成金红石，在碱浸过程中它们均不会溶解而进入铝精矿中。
제출열활화탈규기술처리모매계류철광부선미광제비려정광，대제비양화려정광적공예제도급탈규궤리진행연구。결과표명：해미광괄의적열화학활화탈규제도위활화배소온도1150℃、배소시간15~20 min、감침용규온도125~140℃、용출시간30 min、NaOH농도140 g/L。재차조건하，대Al 2 O 3화SiO 2함량분별위46.22%화28.33%(질량분수)적류철광부선미광，배사SiO 2용출솔체도71.91%，소득려정광중Al 2 O 3함량체69.29%，려규비5.59。XRD결과표명：류철광미광중이리-몽탈석、고령석화협석석등려규산광물재배소과정중활화분해생성무정형SiO 2화소량막래석，여차동시，일수경려석전변성α-Al 2 O 3。재배사적감침과정중，무정형SiO 2용해우NaOH용액피탈제，이α-Al2O3화막래석불능용해，동시생성적수합려규산납(Na8Al6Si6O24(OH)2(H2O)2)장도치SiO2용출솔강저。배소과정중미광중적황철광전화위적철광、예태광부분전화성금홍석，재감침과정중타문균불회용해이진입려정광중。
Aiming at preparing alumina concentrate from coal-derived pyrite flotation tailing, a desilication technique using thermochemical activation process followed by alkali leaching was proposed, and the suitable processing parameters and desilication mechanism were investigated. The results show that the optimal thermochemical activation processing parameters are as follows: roasting temperature 1 150 ℃, roasting time 15-20 min, alkali leaching temperature 125-140 ℃, leaching time 30 min and NaOH concentration 140 g/L. In this case, an alumina concentrate with 69.29%Al2O3 and mass ratio of alumina to silica (A/S) of 5.59 is obtained from a pyrite flotation tailing bearing 46.22%Al 2 O 3 and 28.33%SiO 2 (mass fraction), and the corresponding desilication ratio is 71.91%. XRD results show that aluminosilicates of the pyrite flotation tailing, including illite-montmorillonite, kaolinite and pyrophyllite, are decomposed into amorphous SiO 2 and small amount of mullite after thermochemical activation. Meanwhile, diaspore is transformed intoα-Al 2 O 3 . During the alkali leaching of activated materials, amorphous SiO 2 dissolves in the caustic soda, while mullite and α-Al2O3 do not dissolve, and the formation of sodium aluminosilicate hydrate (Na8Al6Si6O24(OH)2(H2O)2 ) during leaching leads to a decrease of desilication. Otherwise, rutile from thermal transformation of portion anatase, as well as hematite from oxidation, is not capable of being dissolved in alkali solution and shifted to alumina concentrate.