Patent ID: 7816127

Claim:
A waste treatment apparatus for performing volume reduction-annihilation treatment by decomposing waste using microorganisms while the waste is agitated, the waste treatment apparatus comprising: a treatment tank which accommodates the microorganisms and the waste; and an agitation device arranged to agitate the microorganisms and the waste, the agitation device including a rotation shaft provided in the treatment tank and a plurality of agitating tools arranged at predetermined intervals in an axial direction of the rotation shaft; wherein at least one of the agitating tools defines a first agitating tool that includes a pair of paddle arms and a pair of blades, the pair of paddle arms being disposed so as to be opposed to each other in a diameter direction of the rotation shaft, each of the pair of blades being disposed in an end portion of a respective one of the pair of paddle arms so as to be inclined with respect to an axis of the respective one of the pair of paddle arms and so as to be separated from an inner wall of the treatment tank by a predetermined distance; each of the pair of blades includes a leading edge and a trailing edge arranged such that the leading edge is disposed ahead of the trailing edge in a rotation direction of the pair of paddle arms; one of the pair of blades is inclined forward such that the leading edge is disposed closer to the rotation shaft than the trailing edge, and the other one of the pair of blades is inclined backward such that trailing edge is disposed closer to the rotation shaft than the leading edge; at least two of the agitating tools define second agitating tools that include a pair of paddle arms, the pair of paddle arms being disposed so as to be opposed to each other in a diameter direction of the rotation shaft, each of the pair of paddle arms includes a substantially rectangular plate-shaped arm body including a groove portion in a principal surface thereof; and the at least two second agitating tools are disposed at opposed ends of the rotation shaft in the axial direction of the rotation shaft and the at least one first agitating tool is disposed therebetween.