Coal gangue sandstone sponge brick and preparation method thereof

The invention belongs to the technical field of comprehensive utilization of solid waste resources, and particularly relates to a coal gangue sandstone sponge brick and a preparation method thereof. The coal gangue sandstone sponge brick is prepared from, by mass, 50%-80% of coal gangue, 20%-50% of sandstone and a binder solution accounting for 6%-8% of the total mass of the coal gangue and the sandstone. The preparation method comprises the following steps: S1, weighing the coal gangue, the sandstone and the binder solution in proportion, stirring the coal gangue and the sandstone, slowly dropwise adding the binder solution in the stirring process, and continuously conducting stirring uniformly to obtain a mixture; and S2, putting the mixture into a mold, generating a green body through pressure of a pressing machine, placing the green body in a room for drying in the shade, then conducting drying, putting the green body into a firing plate, and conducting firing, so as to obtain a sponge brick. According to