What is the manufacturing process of industrial silicon metal powder?
Silicon powder manufacturing process.
1. Silicon block material is the main raw material for preparing metallic silicon powder. Its effect is better, the application of more Raymond, roller, disc grinding and punch. The equipment used are Raymond, roller, disc mill (also known as vertical mill) and punch and spin method. From the principle of pulverizing, the first three kinds of crushing is extrusion, after the three kinds of impact crushing, from the structure of the point of view, almost the same, each has its own characteristics, each has its own advantages and disadvantages.
2. Influence of pulverizing process on reactivity of silicon metal powder. The reactivity of silicon powder is the ability of silicon powder to participate in chemical reaction to produce products. Its performance for two aspects: one is fast reaction, good stability, and easy to control; Secondly, the reaction is complete and the unit consumption is low, that is, the amount of silica powder used in the synthesis of 1 T methylchlorosilane is small.
In order to obtain highly active silicon powders, the preparation method of high bulk, chemical composition of silicon bulk, environmental conditions and preparation method of metallic silicon powders must reach a better level. In fact, the pulverizing process also has an important effect on the activity of silica powder. The criteria for judging the activity of fly ash mainly include the microstructure, specific surface area, particle size distribution and production and application effect of fly ash, which are described as follows:
The first is the effect of the process of powder production on the microstructure of silicon powder. In the process of refining, the silicon metal with satisfactory chemical composition obtained good microstructure, which ensured its good activity in the synthesis reaction. In the process of powder preparation, the damage to its microstructure should be reduced as much as possible, and the deformation of grains and grain groups should be reduced, so that most of the silicon metal powder can keep the original microstructure to maintain or improve its activity. Of the four methods listed, the impingement method works better because it uses a volleying strike to break the silicon block itself up along the weaker link of the body without deforming the structure.
The second is the influence of pulverizing technology on the specific surface of silica powder. The surface area of silicon metal powder is an important factor affecting the reaction ability. The larger the silicon powder specific surface is, the larger the chloromethane is exposed to, the higher the reactivity, the higher the silicon utilization rate and the lower the unit consumption. Therefore, the silicon powder specific surface is an important index to judge the reactivity. It can be seen from Table 1 that the specific surface area of silicon metal powder obtained by the punching method is larger.
