REMOVAL OF PHOSPHATE CONTAINED IN LIQUID

PURPOSE:To maintain a condition suitable for crystallization of phosphates and enhance the efficiency in removing phosphates, by a method wherein phosphate ores are floated and ore particles of larger particle size being settled are removed, in washing a phosphate ore layer. CONSTITUTION:After feeding air through a washing water inlet 5 and passing it through the phosphate ore layer 2 at a velocity of 20-100m/H, backwashing water is supplied through the inlet 5 and passed through the ore layer 2 at a velocity of 20-100m/H. Due to the buoyancy provided by the backwashing water, the phosphate ore is floated and is expanded as a whole. Then, the particles of larger particle size are classified into a lower layer because of their higher sedimentation velocity, while the particles of smaller particle size are classified into an upper layer. Thus, enlarged particles of the phosphate ore are classified at a lower part of the layer 2, and are discharged to the exterior of the tank through an extracting pipe 8.