Reflux system of immobilized microorganism biological aerated filter

The utility model discloses an immobilized microorganism biological aerated filter backflow system which comprises a backflow tank with the section being in a concave shape with an upward opening, a lifting plate is connected in the backflow tank in a sliding mode, a fixing plate is welded to the inner side wall of the backflow tank, and a threaded rod is rotationally connected to the upper surface of the lifting plate through a bearing. The threaded rod is in threaded connection with the fixing plate, the section, located above the fixing plate, of the threaded rod is of a smooth structure, a plurality of stirring blades are welded to the side wall of the threaded rod, threads are arranged on the other part of the threaded rod, a motor is welded to the side wall of the backflow pool through a support, and a rotating shaft is welded to an output shaft of the motor; the rotating shaft is rotationally connected with the side wall of the backflow pool through a bearing in a penetrating mode, a rotating disc is w