Process for purifying ganister sand from silicon carbide reclamation sand

Abstract

The invention discloses a process for purifying ganister sand from silicon carbide reclamation sand. The process includes the following steps that silicon carbide reclamation sand mortar is subjected to filter pressing, so that a silicon carbide filter cake is obtained; the silicon carbide filter cake and water are put into a ground pool at the weight ratio of 1:8, mixed and thoroughly stirred evenly; silicon carbide filter cake suspension liquid obtained after stirring is conveyed to a swirling tank through a pump to be swirled; obtained upper-layer ganister sand suspension liquid is subjected to filter pressing, and wet raw ganister sand is obtained; the wet raw ganister sand, industrial bromine and water are added into an agitator at the weight ratio of 4:1:5 and stand after being thoroughly stirred evenly; and high-purity ganister sand separated from the upper layer is subjected to filter pressing through a filter press and then collected. The process for purifying the ganister sand from the silicon carbide reclamation sand can improve the resource utilization rate, reduce environment pollution, turn waste into wealth and enable crystalline silicon and silicon carbide to be used reasonably, so that the long-term problem of waste pollution is solved.

Description

technical field

[0001] The invention relates to the field of purification of waste mortar, in particular to a process for purifying silicon powder from silicon carbide recycled sand. Background technique

[0002] In recent years, researchers in the field of photovoltaics at home and abroad have been working on the separation of solid particles (silicon and silicon carbide) in the waste mortar of multi-wire saw cutting, in order to find a feasible and economical method to separate and purify silicon and silicon carbide in the mortar. silicon carbide. Yang Jianfeng and others applied for a patent entitled "A method for recovering silicon powder and silicon carbide powder from cutting waste mortar". The main content includes solid-liquid separation of wire saw cutting waste mortar, using organic solvents to remove suspending agent and binder in waste mortar, and then performing air flow flotation purification on the obtained solid phase to obtain silicon powder of a certain pu...