It is well known that grinding is a high-energy, low-efficiency operation. If the grinding method is used for ultra-fine powder processing, the grinding time is long and the energy consumed is more. Grinding operations are very inefficient, about 1% or even lower, and some of the input energy is used to generate heat, useless impact, extrusion, wear, static energy, elastic and plastic deformation and sound. In recent years, the demand for wet grinding ultra-fine technology has increased in the deep processing of non-metallic minerals. Solving the problem of energy saving and consumption reduction in the ultra-fine pulverization process has become the top priority of non-metallic mineral deep processing.
According to the experts of Veken Heavy Industry, the research proves that good chemical effects can be obtained by adding a small amount of chemical substances in the process of dry pulverization or wet pulverization. These chemical additives are called grinding aids.
Grinding aids are chemicals (solid, liquid or solid) that significantly increase the efficiency of pulverization or low energy consumption during the comminution process, and are usually indicative of active substances. The pulverizing operation, especially the ultra-crushing operation, has high energy consumption and low energy utilization. Therefore, the research of grinding aids has important theoretical and practical significance for improving the ultrafine pulverization efficiency.
The use of grinding mills for warm grinding to produce ultra-fine powders is very active in foreign countries. There are usually two representative theories about the mechanism of action of grinding aids: the first is the theory of “adsorption reduction hardness†led by Rebinder, which means that the adsorption of grinding aid molecules on the particles reduces the surface freedom of the particles. Can, or cause dislocation migration of surface features, resulting in point or line defects. Thereby reducing the strength and hardness of the particles, promoting the generation and expansion of cracks. Therefore, the grinding energy consumption is reduced and the grinding effect is improved. The second is the theory of "mineral rheology regulation" headed by Cranpal. It is believed that the grinding aid can reduce the viscosity of the slurry by adjusting the rheological properties of the slurry and the surface electrical properties of the particles. Dispersion, thereby increasing the fluidity of the slurry, preventing agglomeration and adhesion between the particles, between the particles and the grinding media and the liner. The former starts from the microscopic level and believes that the chemical agent adsorbs on the deformed micro-slit surface to reduce the solid surface energy. When the defect surface along the deformed solid penetrates in two-dimensional movement, side pressure is generated, which acts as a split and prevents the defect from being unloaded. Regroup. This reduces the microscopic strength of the solid and the toughness under ambient load, thereby increasing its deformation. The latter is based on the combination of the characteristics of slurry and grinding effect. From the macroscopic point of view, it is pointed out that the role of grinding aid is to control the viscosity and fluidity of the slurry, while the change of fluidity changes the particle in YGMX. The distribution in the ultrafine mill and the grinding action of the medium; the grinding aid prevents mutual adhesion or agglomeration between the particles by maintaining good dispersion of the particles.
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