Study On The Design Of Multifunctional Magnetic Cyclone For Separation Classification And Desliming

In the process of iron ore separation,a large number of fine mud and coarse ore are the main factors affecting the grade of iron concentrate.The overflow type and the bottom flow type magnetic cyclone can realize the desliming and separation and classification of iron ore respectively,but it is difficult to realize the desliming and separation and classification synchronously with the two types of cyclone.Therefore,this paper designs a kind of multifunctional magnetic cyclone which synchronizes desliming with separation and classification,which can remove the fine mud and coarse particles at one time,so as to achieve the purpose of lifting iron and reducing silicon.On the one hand,it can avoid the separation of some monomer and qualified magnetite particles into the sand settling of the cyclone,and then lead to overgrinding as sand returning.On the other hand,the separation of the coarse particles and magnetite can reduce the processing capacity of the subsequent fine screen,reduce the burden of the fine screen,and even eliminate the fine screen.In the separation of magnetite,it can replace the magnetic gravity separation column or reverse flotation process to remove a lot of fine mud and connective body,and improve the grade of iron concentrate.The internal flow field of a multifunctional magnetic cyclone was simulated in a non-magnetic system.It was found that the radial velocity of the underflow port of 20 mm was basically greater than that of the underflow port of 10 mm at the radial velocity.The difference between the two underflow port at the axial velocity was not obvious,and the difference was greater at the underflow port of 10 mm at the tangential velocity.Because tangential velocity determines the centrifugal force of particles in the flow field and directly affects the separation efficiency of the cyclone,it occupies a dominant position among the three speeds.Therefore,the underflow port with a large tangential velocity of 10 mm is more conducive to the separation of the magnetic cyclone.Desliming and separation tests were carried out for a new type of magnetic cyclone.(1)after adding a magnetic field(magnetic pole head)to the underflow port,it is found that the overflow flow is large at the bottom of the flow mouth,and the recovery effect of magnetic material is obvious;When the underflow port is large,the discharge is small,the total content of magnetic material is low,and the recovery effect of magnetic material is not obvious.(2)an optimization test was carried out on the insertion depth of the overflow tube,and it was found that the recovery rate of the magnetic substance in the overflow decreased significantly after adding the magnetic system.Especially in the magnetic system,when the depth of the overflow tube is 165 mm,the recovery rate of the magnetic material is the lowest,the recovery effect of magnetite is the best,the effect of mud removal is also the best.(3)The radial magnetic field of magnetic cyclone has carried on the comparative study,and compared the blank(no magnetic department),4N and positive spiral magnetic flow from bottom and side stream magnetic material recovery,find best is spiral in the department of magnetic separation classification effect,under the positive spiral magnetic department bottom flow rate reached 74.84%,higher than blank magnetic material under the condition of recovery of 10%.The magnetic field simulation of the magnetic pole head and the radial magnetic field system was carried out by ANSYS MAXWELL,and the differences of the magnetic field gradients among the magnetic systems were compared.It is found that among the three magnetic systems of magnetic pole head,the magnetic field gradient difference between magnetic system 1,magnetic system 2 and magnetic system 3 becomes more obvious as the distance from the magnetic system of magnetic pole head increases,and magnetic field gradient of magnetic system 3 is the largest,and the magnetic field force generated and the influence range of magnetic field is the widest,which can generate stronger magnetic field force on magnetic particles.By comparing the simulation results of 5 kinds of magnetic systems of radial magnetic field,the magnetic field of 4N magnetic system has a wider influence range and generates the strongest magnetic field force,followed by 3N magnetic system and N-S magnetic system.The helical magnetic field force is close to the 3N magnetic system and the N-S magnetic system,but weaker than the 4N magnetic system,and the magnetic field gradient of the positive and negative helical magnetic system is the same.