Method for preparing fracturing propping agent for shale gas exploitation by utilizing slag

The invention discloses a method for preparing a fracturing propping agent for shale gas exploitation by utilizing slag. According to the method, slag serves as a main material, and high-temperature alumina dust collecting powder, alumina powdered waste and spodumene tailings form a composite sintering aid, wherein the slag is high in carbon content, lots of gas can be generated inside a propping agent when carbon is burnt at a high temperature, and the gas is closed in the local area of small granules of the propping agent by utilizing a high-viscosity liquid phase generated by the sintering aid, so that massive distributed tiny closed pores can be formed to achieve the effects of reducing density and increasing pressure resistance. According to the method, the used slag and the adopted composite sintering aid are waste materials, so that natural resources can be saved favorably, the technical content and additional value of the product can be increased, and the economical benefit can be improved.