(1) Principle of sorting According to Fig. 2(a), the Lorentz force becomes buoyancy upward. Since the Lorentz force can be used as the buoyancy force, the magnetohydrodynamic beneficiation can use a uniform magnetic field, which is different from the magnetohydrostatic beneficiation. When the ore is in a static equilibrium state in the magnetohydrodynamic concentrator, the balance of the force is: The working medium upward force (prescribed downward action is positive, upward action is negative) for the uneven magnetic field and the uniform magnetic field are: The Lorentz force is great. According to the actual measurement: when the magnetic pole gap is 10 cm, the magnetic field strength is 0.2-0.5 Tesla, the current density is 0.02-0.2 A/cm 3 , and when the sodium hydroxide solution is used as the conductive medium, the Lorentz force acts on the medium. Aggravated", equivalent to increasing the density q ~ 36 cm 3 . There are many types of magnetohydrodynamic concentrators, but their construction is similar. Figure 3 is one of them. Its cross section is rectangular. The feed zone and the discharge zone must be layered with horizontal partitions to prevent eddy currents from stratification due to the combined action of the electric field and magnetic fields. The electrodes are mounted at appropriate locations in the sorting zone to energize the solution. The polarity of the electrodes should be matched to the polarity of the poles in order to produce a Lorentz force opposite to the direction of gravity (to make the Lorentz force upward). For electric and magnetic field power supplies, rectified DC is required. MTCV Series Flow Control Valves Mtcv Series Flow Control Valves,Hydraulic Flow Control,Hydraulic Speed Control Valve,One-Way Throttle Valve Jiangsu haohong hydraulic Co.Ltd , https://www.jshhhydraulic.com
The difference between magnetohydrodynamic beneficiation and magnetohydrostatic beneficiation is that it has an electric field in addition to a magnetic field (which may be an inhomogeneous magnetic field or a uniform magnetic field) as well as magnetic hydrostatic beneficiation. Electrons flow through the electric field. Electron motion, that is, the charging motion of electrolyte ions as a working medium. The generation of electrons is the result of energization of the plate electrodes placed on both sides of the magnetic fluid. Its working principle is shown as in Fig. 1. When the electrode is energized, the electrons move in the flat space, producing a Lorentz force. The direction of this force is shown in Figure 2. 
The Lorentz force F e can be expressed as the product of the current density J (vector) and the magnetic induction intensity B (vector), ie: [next]
(2) Sorting equipment
According to the Soviet Union data: the use of a magnetic fluid power concentrator to sort the cassiterite , which occupies 2/3 less than the ordinary re-election equipment , and reduces the production cost by 6%.