Efficient Sorting And Theoretical Study Of Fine-grained Mica Resources In Dahongshan Iron Tailings

Mica,as an essential non-metallic material,has been widely used in modern industrial production,however,it has limits including low utilisation,and defects arising as a result of mineral separation.Although most of mica tailings comprised 30 to 40%mica,fine particles and micro-fine particles of mica are difficult to recycle.Floatation is used the main separation technique for fine mica particles,however floatation of mica has shortfalls such as poor performance in the selection of collectors and being susceptible to interference from mineral mud.Besides,floatation of the majority of micas requires pre-treatment by desliming to allow normal floatation.However,the desliming process takes longer,and results in additional process complexity,leading to the loss of large amount of micron sized particles,consequently reducing the utilisation of the mica resources.Hence it is worth developing a mica collector with efficient non-interference from the surrounding mud to improve mica ore utilisation and simplify the separation process.Micron-sized micas are abundantly distributed:tailings containing metallic,and non-metallic,ores are shown to contain large amounts of micron-sized mica particles,however the separation-related parameters of such micas give rise to poor process performance.The recycling of mica,from such tailings,can realize the dual benefit of resource recycling and waste reduction:it can bring about economic benefit resulting from concentration of the mica thus obtained,and produce environmental benefits with reduced emission of tailings.Thus,both economic and social benefits are expected to be generated due to the development of techniques for recycling micron-sized mica particles in tailings.Atypical iron ore mine,at which separation has proven difficult,is the Dahongshan iron ore mine Yuxi,Yunnan Province,China,was taken as the research object for this study involving the recycling of micron-sized mica particles.In this mine,the production of tailings amounted to 7 million tons per year,among which,the mica resource amounted to 600,000 tons per year(with an overall value of several hundreds of millions of yuan).Due to disadvantages such as the complex mineral composition,high mineral mud content,and low mica ore grade,the separation of mica from these tailings is difficult.The efficient separation of micron-sized mica particles from tailings is expected to be a feasible method for realising mica resource recovery and reduction of tailings waste in China.For this reason,a process mineralogy study of Dahongshan iron ore mine materials was performed:this investigated the characteristics of the composition,content,distribution,and patchiness of the minerals in the mine.Moreover,an electronic probe was used to conduct this analysis of those minerals present.This analysis attempted to provide a reference for ore separation in real production.Based on the research results,representative mono-mineral ore samples including muscovite,orthoclase,quartz,and clinochlore were chosen to assess the efficacy of the chosen floatation process.Using flocculation floatation as a processing technique,the variation of floatability for the minerals under the effects of different collectors was studied.Afterwards,agglomeration differences among mineral particles with different collectors were examined by constructing a sedimentary dynamics model.Lastly,an efficient anion and cation mixed collector combining SDS and DDA was developed.This collector was able to realise hydrophobic selectivity and selective agglomeration of micas.When analysing the effects of agglomeration some minerals show synergistic effects in this case.Moreover,the key reasons for using desliming pre-treatment in actual floatation processing of micas using traditional anion and cation mixed collector combinations(NaOL and DDA)were revealed.Based on the results of floatation and agglomeration testing of mono-mineral ores,the effects of using different collectors were analysed.Adsorption measurements revealed that the surfaces of different minerals,under the influence of the cationic-anionic collectors' combination,exhibited significantly different cooperative adsorptions and mutual inhibition.This result explicitly demonstrated the reason for choosing the aforementioned collector combination.Moreover,solution composition and zeta potential analysis were used to reveal the mechanism of adsorption of the different compositions and collector combinations on the mineral surfaces.Using infrared spectrum analysis,the means of adsorption in different collectors were studied,and results provided evidence to prove the presence of a cooperative adsorption effect in an cationic-anionic collectors'combination.X-ray photoelectron spectroscopy(XPS)further verified the results obtained in the adsorption measurements.Based on the association complex of the cationic-anionic collectors' combination,a model for the adsorption of the collector on the diverse mineral surfaces was built,which reasonably explained the reasons underpinning the choice of cationic-anionic collectors' combination.According to the aforementioned results,micron-sized mica particles contained in the tailings of Dahongshan iron ore mine were recycled efficiently and the separation of iron concentrate and quartz was conducted.This work improved the concentration of micas,iron,and quartz to a level of applicable significance,improved resource utilisation at the Dahongshan iron mine,reduced the emission of tailing waste,and thus allowed effective resource recycling.