2.分析珠(球)磨機中的研磨過程的特征
珠(球)磨機是一種用濕法進行超微細粉碎的設備。該珠(球)磨機由一個帶軸的垂直(或水平)研磨室組成。該腔室包含一個轉子,該轉子由一個帶有圓盤或桿的軸組成。腔體充滿了70-80%的玄武巖,玻璃或鋼珠。當轉子旋轉時,材料的固體顆粒由于在研磨的主體上相互摩擦而被壓碎。生產(chǎn)型的珠(球)磨機以周期性,連續(xù)式或循環(huán)式工作。該研磨機具有篩筒或狹縫以分離研磨珠與懸浮液。產(chǎn)品的最終粒徑可以小于1μm(Rowe W.B.,2014; Salenko YU。,2008; Grining K.,Tarasenko M.,2017)。珠磨機中的精細研磨過程取決于許多操作參數(shù)。研究表明,重要因素包括:機械能,比能耗,研磨體碰撞能量,研磨體與產(chǎn)品的有效碰撞次數(shù),以及顆粒在研磨機中的停留時間(Mende S. ,Rappl M.,2014; Rowe WB,2014)。此外,在研磨時,物質表面的氣體和液體殘余物的解吸被破碎,結果固體的表面積發(fā)生變化(Dr?gemeierR。,Leschonski K.,1994)。機械能是從轉子通過珠子傳遞到懸浮液的能量。引入系統(tǒng)的能量越多,破壞強結塊的可能性就越大(Dr?gemeierR。,Leschonski K.,1994)。能量可以以多種方式引入:具有高轉子速度和低扭矩,或反之亦然,在高扭矩和低旋轉速度下(Nakach,M.,Authelin,J.,Agut,C。2017)。
2. Analysis of the features of the grinding process in a bead mill
The bead mill is an equipment for thin and superfine grinding, which occurs by a wet method.
The mill consists of a vertical (or horizontal) grinding chamber with a shirt. The chamber contains a rotor which consist of a shaft with disks or rods attached to it. The camera is filled with 70-80% beads from a basalt, glass or steel. When the rotor rotates, the solid particles of the material are crushed as a result of the friction on the body that is grinding, and each other. An industrial bead mill works in periodic, continuous or circulating modes. The mill has a sieve cartridge or a slit to separate the beads from the suspension. The size of the crushed product can reach less than 1 μm (Rowe W.B., 2014; Salenko YU., 2008; Grining K., Tarasenko M., 2017).The process of fine grinding in the bead mills depend to many operating parameters. The studies have shown that important factors are: mechanical energy, specific energy consumption, energy of collisions of grinding bodies, the number of effective collisions of grinding bodies with the product, as well as the residence time of particles in the mill (Mende S.,Rappl M., 2014; Rowe W.B.,2014). In addition, at grinding the desorption of gas and liquid residues from the surface of the substance is shattered, as a result the surface area of the solid changes (Dr?gemeier R.,Leschonski K., 1994).
Mechanical energy is the energy that is transmitted from the rotor through the beads to the suspension. The more energy is introduced into the system, the greater the likelihood of the destruction of strong agglomerates(Dr?gemeier R., Leschonski K., 1994). Energy can be introduced in several ways: with high rotor speed and low torque, or vice versa, at high torque and low rotational speed (Nakach, M., Authelin,J., Agut, C. 2017)