A method for a reclamation of waste sand comprising bentonite binder, in which method it is subjected a thermal treatment to the waste sand for removing carbon and absorbed moisture from the bentonite binder in the waste sand, it is subjected a mechanical treatment to the thermally treated waste sand for mechanically separating the sand from the bentonite binder, and it is subjected a cooling effect to the sand separated from the bentonite binder. Additionally, it is introduced an apparatus for a reclamation of waste sand comprising bentonite binder, sand for a building industry product. a foundry sand, or a power plant boiler sand, and a use of reclaimed sand in a building industry product, in a foundry sand, or in a power plant boiler sand.

A sand core making machine that includes a hopper having a hollow body with an inner surface delimiting a passageway for a material used in the manufacture of a sand core. The hopper includes a plurality of breaker assemblies with each breaker assembly having at least one string. The ends of a string are attached to corresponding attachment points of the inner surface of the hollow body, such that the strings are arranged in a flow passage of the material. At least two breaker assemblies are spaced apart such that the two breaker assemblies interact with each other to break lumps of the material supplied to the hopper when the hollow body is shaken.