Large volumes of water suction, low power consumption; Long service life of wear parts Each tank with air suction, slurry suction and flotation function does not need any accessory equipment to form flotation circle, the which is convenient for changing process flow; The reasonable slurry circulation minimizes coarse sand sediments, and is conducive to flotation of coarse particle; Auto-control device of slurry volume, convenient adjustment; Impeller with backward style upper and lower leaf, the upper blade generates upper circulation; the lower blade