The precipitated and concentrated ore particles are deposited from the slurry by their own action. During the precipitation process, the ore particles settle according to the law of solid movement in the medium. In a very short period of time after the initial settlement, the ore particles settle down with acceleration. After that, due to the resistance of the medium, the ore particles gradually balance with the gravity of the ore particles, and the ore particles gradually move at a constant speed. This speed is called the final velocity of sedimentation. In the pulp, the size of the ore group is not uniform, and the purpose of sedimentation is to hope that all the ore particles are settled to obtain a clear liquid, so the sedimentation velocity of the ore particles must be calculated according to the final velocity of the minimum particles. Generally calculated according to the Stokes formula, ie
It can be seen from the above formula that the sedimentation velocity affecting the ore particles is mainly related to the following factors: size d of the ore, density δ, shape x, medium viscosity μ (related to slurry temperature), medium density △ (with slurry concentration and density) Related). In addition, the presence of soluble salts in the pulp also has an effect.
It can be seen from the above formula that the particle size of the ore particles has the greatest influence on the final velocity of the sedimentation, because it is proportional to the square of the particle size, so the finer the ore particles, the slower the sedimentation velocity. Therefore, in the sedimentation process, the most difficult to settle is the fine slime. The more mud in the slurry, the more difficult the clarification is, and the suspension is often in the pulp. The main reason is that there are double layers on the surface of the fine mud. With the same-sex charge, there is mutual repulsion. Due to the Brownian motion, the sedimentation of fine ore particles tends to be balanced. In the production practice, in order to accelerate the sedimentation of the micro-strong ore particles, a certain coagulant may be added to the slurry to improve the precipitation concentration effect of the fine ore particles.
The viscosity of the slurry also significantly affects the sedimentation rate of the particles. As can be seen from the above equation, v0 is inversely proportional to μ. The viscosity of the pulp decreases with increasing temperature. Therefore, heating the slurry can accelerate the sedimentation of the fine particles, but heating the slurry consumes energy, and it is necessary to consider the economic effect when applied to production.
In addition, the lower the concentration of the slurry, the smaller the density of the medium, and the mutual interference of the ore particles is also small, so that the sedimentation of the particles is facilitated. It can be seen that the lower the concentration of the slurry, the better the sedimentation.
Melt-blown fabrics have generally the same applications as other nonwoven products. The main uses of melt-blown nonwovens and other innovative approaches are as follows.
Melt Blown Die,Mould Of Melt Blown Spinnerets,Dense Hole Spinneret,Large Hole Spinneret
Changzhou Jier Precision Machinery Manufacturing Co., Ltd. , https://www.jier-spinneret.com