NOVELTY - Biogas device comprises a total reaction chamber, where upper part of chamber has pH electrode probe, feeding port (5), motor, exhaust pipe (6), and liquid level sensor, the chamber is connected with transmission shaft of engine, the outlet end of alkali liquid tank (1) is connected with liquid pipe (4), a liquid pipe is U-shaped pipe (3) connected in series which is connected with electromagnetic valve (2), pH value electrode probe and electromagnetic valve is connected by wire and control is connected with the chamber having water bath chamber having reflux water inlet/outlet pipe.    USE - As biogas device for improving anaerobic digestion marsh gas of kitchen garbage (claimed).    ADVANTAGE - The device is simple, has high automatic degree, improve enzyme activity of strain producing marsh gas, saves the operation cost, and is easy to operate.    DETAILED DESCRIPTION - Biogas device, comprises a total reaction chamber (12), where the upper part of chamber is provided with a pH electrode probe (17), a feeding port (5), a motor (8), an exhaust pipe (6), liquid level sensor (22), the reaction chamber is connected with the transmission shaft of the engine of the stirring paddle (13), the outlet end of the alkali liquid tank (1) is connected with a liquid pipe (4), one end of the liquid pipe of the other one end is completely mixed with reaction chamber of the upper end face of a liquid pipe is U-shaped pipe connected in series, a U-shaped pipe (3) is connected with a liquid tank is provided with an electromagnetic valve (2), the pH value electrode probe, an electromagnetic valve by a wire (18) is connected with the signal processing and control (19) is connected with the total mixing reaction chamber are respectively provided with a sampling pipe wall (12) of the body (9), a sampling tube (10), pipe (11), completely mixing and reacting chamber is provided with a water bath chamber (15), the water bath chamber of the side wall is provided with a reflux water inlet pipe (14), a return water outlet pipe (16).    DESCRIPTION OF DRAWING(S) - The figure shows a schematic diagram of a biogas device.    Alkali liquid tank (1)    Electromagnetic valve (2)    U-shaped pipe (3)    Liquid pipe (4)    Feeding port (5)    Exhaust pipe (6)