AGITATOR OF ANAEROBIC DIGESTER

An agitator for an anaerobic digester is provided to prevent bending or damage to the scrapers by allowing the scrapers to receive a uniform load when scrapers are rotated, prevent the sediment from accumulating on the bottom of the anaerobic digester by slowly rotating the scrapers and scraping a sediment settled on the bottom of the anaerobic digester, and prevent the rotation of the scrapers from interfering with the multiplying environment of anaerobic microorganisms. An agitator for an anaerobic digester(60) is characterized in that: an annular gear(20) is driven by a drive gear(12) mounted on a drive shaft(11) of a drive motor(10); the annular gear is supported by an annular support(61) disposed on the inner peripheral surface of an upper end of the anaerobic digester; steel balls are disposed between the support and the annular gear so that the annular gear is rotated on the support in a state that the annular gear is geared with the drive gear; the annular gear is connected to upper ends of vertical posts(30); the number of vertical posts mounted on the annular gear is varied such that various shaped scrapers(40) can be mounted on lower ends of the vertical posts; and the scrapers mounted on the lower ends of the vertical posts are rotated about their centers of rotation by the rotation of the annular gear so as to scrape a sediment accumulated on a bottom face(62) of the anaerobic digester.