Method for floating silicon from silicon slag

Abstract

The invention discloses a method for recovering metallic silicon from silicon slag through flotation, comprising the following steps of: 1) silicon slag crushing: crushing the silicon slag by using acrusher, and putting the crushed silicon slag into a ball milling tank made of stainless steel for ball milling; 2) sieving: sieving the ground silicon slag to obtain silicon slag powder with the particle size of not more than 170 meshes; 3) surface treatment: carrying out surface treatment on the silicon slag powder by using a surface treatment agent, and stirring to fully mix the silicon slag powder to form silicon slag slurry; 4) flotation: adding a collecting agent foaming agent into the fully-mixed silicon slag slurry and stirring uniformly, putting the mixture into a flotation machine for flotation, and starting foam scraping after foam is rich, thereby obtaining a silicon-rich phase and a silicon-poor phase; and 5) silicon-rich phase treatment: filtering the silicon-rich phase, washing and drying to obtain a silicon-rich product, so that efficient recycling of silicon slag resources is achieved.

Description

technical field [0001] The invention belongs to the technical field of silicon slag treatment, and in particular relates to a method for recovering metal silicon from silicon slag by flotation. Background technique [0002] At present, China has grown into the world's largest producer of industrial silicon, with steady growth in production capacity and output. After 2012, the output of industrial silicon has increased, and the proportion of China's industrial silicon in the world has also increased year by year, but the increase rate has decreased year by year. This is due to Due to the characteristics of the industrial silicon industry. Industrial silicon production is greatly affected by seasonality, and industrial silicon smelting needs to consume a large amount of power resources, resulting in high production costs. Yield will be affected to some extent. The contradiction between demand and production has become increasingly prominent, so many industrial silicon manufa...

AI Technical Summary

Problems solved by technology

[0006] At present, there are few researches on flotation separation and recovery of industrial silicon. Flotation separation is applied to the recovery of industrial silicon in silicon slag, which does not need to melt the silicon slag, effectively saves energy, is simple to operate, and has low production costs. value is significant