Process for recycling waste mortar during solar silicon wafer slicing

The invention relates to a process for recycling waste mortar during solar silicon wafer slicing, comprising the following steps of: carrying solid-liquid separation, weighing and adding sand obtained by the solid-liquid separation into a mixed solution of polyethylene glycol containing 2-6% cleaning fluid, stirring for 60-180 minutes according to a program at different mixing speeds, carrying out solid-liquid separation on the mortar, preparing a new cleaning fluid by the separated liquid, adding the separated sand into the mixed solution of polyethylene glycol containing 5-20% surface modifier, fully stirring for 1-2 hours, standing for 6-8 hours in a special storage tank to be subjected to surface modification treatment, packaging with special wet sand packaging bags, and sealing; and carrying out mortar slicing on the separated sand in the packaging bag according to the technological requirement. By adopting the process provided by the invention, the conventional sand washing process is changed, no sewage is discharged, and a green and cyclic regeneration production ideal is met; and the particle size of the recycled separated sand is easy to control, no drying is required, less broken sands are produced in a sorting process, the yield is high, and the application cost is low.