Study On The Solid Liquid Interface Interaction Of Pentlandite/serpentine And Flotation Under Micro-Nanobubbles

Chinese nickel resource type is dominated by microfine-grained embedded nickel sulfide ore and contains a large amount of high magnesium,easy modification,and challenging to suppress serpentine and other vein minerals.The characteristics of the resource determine the need to use fine grinding process flotation to recover nickel and copper,which results in serious serpentine modifications in the ore,leading to high magnesium oxide content in the final nickel concentrate,which seriously affects the product quality.Based on this,this thesis focused on the solid-liquid interface interaction of pentlandite/serpentine and screened out a high-efficiency inhibitor of serpentine.It used micro-nanobubbles to enhance the separation of minerals at the micro-fine grain level and realized the high-efficiency separation of pentlandite and serpentine.The solid-liquid interfacial interaction of lizardite,antigorite,and pentlandite was investigated to reveal the relationship between pH,collector’s type and concentration,depressant’s type and concentration,and flotation behavior of the three pure minerals.The results showed that the finer the particle size of serpentine,the easier it is to be wrapped by air bubbles into the concentrate;the inhibition effect of five depressants,namely sodium hexametaphosphate,sodium alginate,L6,L6010 and sodium carboxymethyl cellulose,on serpentine was compared,and sodium alginate had the best inhibition effect on microfine grain serpentine during single mineral flotation,and the microscopic observation revealed that sodium alginate could flocculate microfine grain serpentine,and the powder dynamic contact angle detection After the action of five kinds of depressants,the contact angle of serpentine is in the order from small to large:CMC<SAG<SHMP<L6010<L6;when sodium carboxymethyl cellulose and sodium alginate were used in combination in the flotation separation of artificial mixed ore,the microfine serpentine adhered to the surface of pentlandite first dispersed and fell off and then gathered to form flocs,which improved the concentrate quality.Nanobubbles were prepared by ultrasonication and stability experiments showed that the bubble size and number did not change after 60 min of resting.Flotation experiments using nanobubbles on single minerals showed that the presence of nanobubbles reduced the flotation of serpentine at the microfine grain level,increased the flotation of pentlandite,and also reduced the amount of depressant.Artificial mixed ore flotation separation experiments showed that nanobubbles increased the nickel grade and decreased the MgO content in the concentrate.The flotation separation experiments were carried out on actual ore containing high serpentine nickel,and the CFD-PBM model was used to simulate the gas-liquid two-phase flow of the micro-nanobubbles generator.The latter achieved high-efficiency separation of pentlandite and serpentine by increasing the nickel grade from 5.09%to 6.71%,increasing the copper grade from 1.46%to 2.08%,and decreasing the magnesium oxide content from 8.33%to 5.25%,a decrease of 3.08 percentage points.