Machine-made sand fineness modulus online adjusting apparatus and method

The invention relates to a machine-made sand fineness modulus online adjusting apparatus and method. A multilayer vibrating screen is used for screening sand and gravel into fine sand with a small particle size and coarse sand with a large particle size, a machine-made sand collection apparatus collects the fine sand, and a returning collection apparatus collects the screening residues. A distribution apparatus collects the coarse sand and distributes the coarse sand to the machine-made sand collection apparatus and the returning collection apparatus in an adjustable manner, so that the amountof the coarse sand entering the machine-made sand collection apparatus is increased or reduced. A dust removal apparatus is used for absorbing fine powder in a working space, and an air volume of thedust removal apparatus as well as the fine powder amount absorbed from the working space can be adjusted by virtue of an air volume adjusting valve, so that the amount of fine powder entering the machine-made sand collection