Flotation Test And Mechanism Discussion Of Carbonaceous Scheelite In Shangri-La, Yunnan

Tungsten ore,a dominant strategic resource in China,has always been focused on its separation from calcium gangue minerals.The flotation performance of scheelite?coming from Shangri-la,Yunnan Province?was discussed in this paper as well as the active mechanism of carbonaceous scheelite.Our work can be for a reference to the efficient recovery of scheelite,or to the application of new flotation agents.Analysis of process mineralogy shows that the main ore to be recovered in raw ore is scheelite disseminated in disproportion.The gangue minerals are mainly calcite,fluorite,and a relatively small amount of quartz.The raw ore also contains carbon inclusion and pyrite.The carbon inclusion can consume a large amount of agents in the flotation process for the significant activity,while pyrite brings a lower grade of the final concentrate.The desulfurization and decarbonization should be implemented in pre-process.And the inhibition technology against calcium gangue minerals should be applied during the flotation.Based on the analysis of process mineralogy,further research on the flotation condition,flow optimization,and whole process simulation is carried out.The whole flotation process of scheelite pre-enrichment and heating concentration with sulphide and carbon pre-removing was proposed in this paper combined with the site process and raw ore properties.For the flotation of scheelite with WO₃ content of 0.43%,concentrate grades and recovery rates are 58.70%and 75.59%respectively,1.18%and 4.10%above production index respectively can be obtained using the above whole flotation process.The pure mineral experiment indicates that XP has a larger scale of the suitable pulp pH value for flotation than NaOL,and the collectivity to scheelite is more significant in the highly acidic or alkaline condition.XP brings a better flotation index and a better selectivity than NaOL's,in spite of the smaller amount of sodium silicate.Infrared spectrum analysis of the flotation agents XP shows that it is a mixture of dimerized fatty acids with two carboxyl groups,which is an unsaturated fatty acid.Infrared spectrum analysis shows that at the same wavelength,the mineral sample reacting with XP or NaOL has the formant coming from adsorption of the carboxyl group on the mineral surface,though XP performs more strength of absorption.The Zeta potential analysis shows that the Zeta potential values from XP and NaOL are close in a neutral or weak alkaline condition.The corresponding Zeta potential of XP is slightly lower in highly acidic or alkaline condition than NaOL's.The SEM-EDS analysis finds more carbon element appearing on the mineral surface after the action of the two collectors respectively,while the corresponding carbon element content of XP increased more significantly.The XPS analysis shows that there are new peaks in O1s and Ca2p,and obvious chemical shifts in C1s and W4f were observed after the action of agents,while the corresponding chemical shift of XP is more obvious.The Quantum chemical calculations show that O in the carboxyl group interacts with Ca on the mineral surface,and the distance between O-Ca is less than the sum of the radius of Ca and O atoms.All the above tests and calculation methods indicate that the interaction between the two agents and scheelite is chemical adsorption,while the acting effects of XP on scheelite is more significant than NaOL's.