METHOD AND APPARATUS FOR SEPARATION OF SAND AND SILT FRACTION

PROBLEM TO BE SOLVED: To provide a simple apparatus which can remove, efficiently in a short time, fine particles containing harmful silt from a fine aggregate of a high content of silt, e.g. pit sand, and purify to a good-quality fine aggregate. SOLUTION: A separation method comprises separating to-be-separated sand 1 into a sludge-like viscous fluid 5 of silt which adheres to the inside surface of the carrying passage 4 and moves downstream and wet 6 which moves downstream without adhesion to the inside surface of the passage, within the carrying passage 4, by pressure-feeding the sand 1, together with water 2 and high-pressure air 3, through a carrying passage 4, and taking out the wet sand 6 and the sludge-like fluid 5 at different locations in the carrying passage 4. The separation apparatus for the method is also provided. COPYRIGHT: (C)2008,JPO&INPIT