Method for preparing solar grade polysilicon by recycling silicon cut wastes

The invention belongs to the field of solar grade polysilicon preparation and in particular provides a method for preparing solar grade polysilicon by recycling silicon cut wastes. The method specifically comprises the following steps of: firstly grinding recycled silicon wastes to the particles suitable for the melting stage, adopting cleaning agents such as water, hydrochloric acid and hydrogen peroxide mixed water solution, hydrofluoric acid water solution, ammonia water, ethanol water solution and the like to clean silicon powder, putting the dried silicon powder in a quartz crucible, and calcining the silicon powder in a vacuum electric furnace or a hydrogen protected electric furnace at 1600 DEG C for 3-5 hours, thus obtaining the solar grade polysilicon. The method has the following beneficial effects: the problem of silicon cut waste treatment is solved; the preparation steps are simple, and the conditions are mild; and the purity of the prepared polysilicon meets the requirement of solar grade silicon.