Method for separating silicon from residuals

Abstract

The invention discloses a method for separating silicon from residuals used in the process of purifying a silicon material by a slag practice, which can effectively separate the purified silicon from residuals after the purification reaction is finished. Based on the method, after the reaction of silicon and residuals is finished and the silicon and the residuals are in a liquid state, the mixed liquid of the silicon and the residuals is poured in a liquid slowly, the liquid can be water or an acid solution or an alkali solution or a water based cooling liquid or an oil-based cooling liquid, and the silicon and the residuals are quenched so as to exchange heat thereof to the cooling liquid, thereby separating the silicon and the residuals due to different physical properties thereof. The silicon and the residuals are quenched, cooled and solidified, the silicon is globoid or botryoidal with a certain size like 3-10mm, the residuals form foam and crisp fine grain solids, the fine grain solids of the residuals are not adhered on the silicon spheres, and the silicon can be taken out by a simple and convenient physical method, e.g. the residuals are kneaded into finer grain solids while the silicon spheres are still in the original shape, and wet sieving is performed to take out the silicon spheres.

Description

technical field [0001] The invention relates to a method for purifying silicon materials, mainly a method for separating silicon and slag, especially a method for conveniently and effectively separating silicon and slag during the smelting process of purifying silicon materials by slagging . Background technique [0002] Purification of silicon material by slagging method is one of the simplest and most feasible methods among various methods of physical purification of silicon material. In principle, the cost performance of slag making method is the highest. Because according to this method, you only need to mix the appropriate slag agent and silicon material together, heat and melt, keep it for a period of time and then take out the silicon; or first heat and melt the silicon material and slag agent separately, and then mix the two liquids , Stir, keep for a period of time and take out the silicon. Unlike other physical purification methods that require more complicated ...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is that part of the slag liquid will be taken out with the silicon

Even if there is a small amount of residue left in the silicon material, the post-cleaning silicon process will be very complicated due to the strong adhesion

At the same time, part of the silicon will remain in the slag, reducing the production efficiency of silicon

Although this method has been widely used in industry, its effectiveness and economy are not ideal

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