NOVELTY - A power-free stirring and fermenting device comprises solubilized tank (1) connected through screw rod pump (6), where the solubilized tank through screw rod pump is connected with the fermentation tank (9) which is connected with waste liquid by waste liquid pump and sewage processing device (17), where the screw pump connected with the fermentation tank is further provided with an electromagnetic flow meter (7).    USE - As a power-free stirring and fermenting device for restaurant and kitchen rubbish (claimed).    ADVANTAGE - The device can save power; is not easy to generate scruff and crust; and avoids pollution.    DETAILED DESCRIPTION - A power-free stirring and fermenting device comprises solubilized tank (1) connected through screw rod pump (6), where the solubilized tank through screw rod pump is connected with the fermentation tank (9) which is connected with waste liquid by waste liquid pump and sewage processing device (17), where the screw pump connected with the fermentation tank is further provided with an electromagnetic flow meter (7), where upper part of the fermentation tank is upper part chamber (11), and the lower part of the fermentation tank is lower chamber (10), the fermentation tank is provided with a stirring shaft (12), where the stirring shaft is provided with a stirring wing with one central guide pipe and the lower part chamber in the upper chamber (13), the upper chamber is provided with a balance valve (8) equipped with biogas slurry overflow pipe on the upper part and lower part chamber (14), and the fermentation tank is provided with a lower part discharging port (15). The solubilized tank is provided with a thermometer (2) and liquid level meter (3). The thermometer and liquid level meter are connected with computer (4).    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of the power-free stirring and fermenting device.    Solubilized tank (1)    Thermometer (2)    Liquid level meter (3)    Computer (4)    Screw rod pump (6)    Electromagnetic flow meter (7)    Balance valve (8)    Fermentation tank (9)    Lower chamber (10)    Upper part chamber (11)    Stirring shaft (12)    Upper chamber (12)    Lower part chamber (14)    Lower part discharging port (15)    Sewage processing device (17)