To make it possible to automatically execute the take-out of residues in a treating device for garbage, or the like, by utilizing their own weight of the residues or a mechanical means necessarily disposed at the treating device.

This device is opened with a port 35 at a position of the wall of a treating vessel 15 of facing a portion where the rotating locus of an agitating arm 23 faces upward. This port is closed by a stationary side and a moving side shutter plates 43 and 45 formed with many residue discharge holes of a longitudinal long hole shape, and the residue discharge holes are opened and closed by sliding the moving side shutter plate 45. If the shutter plate 45 is moved to an open position upon arrival of the residues in the treating vessel 15 at a standard line inscribed at the shutter plate 45, the residues are emitted from the residue discharge holes by their own weight or the agitating motion by the agitating arm 23 and are dropped to a recovery tray 51. The width of the residue discharge holes is set smaller than the diameter of decomposition accelerating balls 57 and, therefore, these decomposition accelerating balls remain. Then, the take-out of the residues is automatically carried out and a part thereof remains surely and microorganisms may be detained to some extent. Sieving of a decomposition accelerating material may be effected as well.