Floating beneficiation process, the floating mineral grain size and sorting indices great relationship. The flocculation of the ore particles to the bubble during flotation is the basic behavior of the flotation process. The adhesion of the ore particles on the bubbles directly affects the quality of the flotation beneficiation, but the adhesion of the ore particles to the bubbles is not only related to the ore particles. In addition to its own hydrophobic size, it is also related to the size of the ore. In general, the small size of the ore particles (except for less than 5 to 10 microns) adheres to the bubbles faster and is firmer. On the contrary, the particle size is coarser, and the adhesion to the bubbles is slower and less firm. The following is an analysis of the stress on the particles attached to the bubbles, as shown in Figure 6-32. As can be seen from Fig. 6-31, the adhesion of the ore particles to the bubbles is affected by the following three forces. (1) The force F1 is the gravity of the ore particles in the water, and the direction is downward, which is the force for removing the ore particles from the bubbles, which is equal to the gravity of the ore particles in the air W=d3δg.陋 Subtract the buoyancy in the water f = d3△g, ie: Where d is the diameter of the ore; the density of the delta; △ - the density of the water. It can be seen from the above formula that the magnitude of the force F1 is proportional to the cube of the size of the ore (d). The larger the ore, the greater the force from the bubble. (2) The force F2 is the surface tension of the ore particles attached to the bubble, specifically, the component of the surface tension acting on the three-phase wetted periphery in the vertical direction, and its direction is upward, which enables the ore particles to The force that remains attached to the bubble, the magnitude of this force is: F2=2πγσ gas-liquid sin θ in the γ-adhesion surface radius; σ gas-liquid-surface tension at the gas-liquid interface; θ——contact angle, degree. It can be seen from the above formula that the adhesion F2 of the ore particles on the bubbles is related to the contact angle of the ore particles, and the contact angle is large, that is, the mineral particles having a large hydrophobicity, and the force F2 adhering to the bubbles is also large. (3) The force F3 is the pressure of the molecules in the bubble on the attachment surface of the ore. This force is the force that causes the ore particles to detach from the bubble, so the direction is downward. Its size is: Where R is the bubble radius. As can be seen from the above formula, when the large bubble (R is large), the pressure F3 is small. When the three forces F1, F2, and F3 are in equilibrium, that is, when the ore particles adhere to the bubble and are close to the falling state, then Equation (6-1) is called the equilibrium equation for the attachment of ore particles to the bubbles. It can be seen that the relationship between the contact angle 臼 and the surface tension, the size of the ore (mine mass), the adhesion radius r and the bubble radius R in the relatively static state between the ore particles. However, in the actual flotation process, the ore particles and the bubbles are relatively moving, and the shedding force between the ore particles and the bubbles is more complicated than at rest, and is much larger than that of the above formula. However, some relations between particle size and floating beneficiation can still be qualitatively seen from formula (6-1). (1) When the ore floatability is good, that is, the mineral with a large contact angle, the floating dressing particle size d can be coarser, of course, there is a certain limit, the so-called upper limit of the particle size. (2) For coarser-grade floating beneficiation, it is more advantageous for the bubble to be larger (R large), or, in the case of larger bubbles, the contact angle of the floated ore dressing mineral can be floated and oreed under a small condition. . However, when the bubble is too large, the stability of the bubble itself is also poor. According to the above analysis, the floating beneficiation particle size is one of the important factors affecting the performance of floating beneficiation. In order to obtain better technical indicators of floating mineral processing technology , it is required to make the grinding fineness reasonable, not only to separate the useful minerals, but also the coarse particles should not be greater than the upper limit of the floating mineralization: the sulfide minerals are generally 0.2-0.25 mm. The natural sulphur with good buoyancy is 0.5-1.0 mm; the coal is thicker, 1-2 mm. industrial defoamer,mechanical defoamer,natural antifoam,organic antifoam,powder defoamer NINGBO LUCKY CHEMICAL INDUSTRY CO. LTD , https://www.luckychemical.com