NOVELTY - A device for producing methane by solid-state fermentation comprises ferment devices (1, 19, 20, 21, 22, 23, 24, 25, 26) composed of fixed pedestal (8), movable internal container (9) and movable water sealing cover (11). The lower end of the pedestal (8) supports the internal container (9) and is connected with a methane liquid output device (5). A water sealing cover (11) is installed on the water groove (10) of the upper end of the pedestal (8) and connected with a methane collection device (7, 25) and a methane liquid backflow device (6).    USE - Device for producing methane by solid-state fermentation (claimed).    DETAILED DESCRIPTION - A device for producing methane by solid-state fermentation comprises ferment devices (1, 19, 20, 21, 22, 23, 24, 25, 26) composed of fixed pedestal (8), movable internal container (9) and movable water sealing cover (11). The lower end of the pedestal (8) supports the internal container (9) and is connected with a methane liquid output device (5). A water sealing cover (11) is installed on the water groove (10) of the upper end of the pedestal (8) and connected with a methane collection device (7, 25) and a methane liquid backflow device (6). The lower end of each ferment device is connected with the methane liquid collection device (5, 26) by the pedestal (8). The methane liquid automatically flows to the methane liquid collection device (5, 26) by pressure difference. The upper end of each ferment device is connected with the methane collection device (7, 25) and the methane liquid backflow device (6) by the water sealing cover (11). The water sealing cover (11) is installed on the water groove (10) at about greater than or equal to 40 cm. Methane liquid backflow holes (12) are arranged on the middle part of the top end of the water sealing cover (11). The side face of the ferment device is provided with methane output holes (14). Water groove (10) is U type with a groove depth of 40 mm. The water sealing cover (11) is installed on the pedestal (8) and is connected with the water groove (10) by a clamping pillar on the internal wall of the bottom end of the water groove. A ring-shaped spraying pipe (13), with radius of 1/3 of the circular face of the water sealing cover, is installed on the top end of the water sealing cover of each ferment device. The diameter of the spraying pipe (13) is less than or equal to 10 cm and the surface has 3 rows of through holes with diameters of 1-2 mm.    DESCRIPTION OF DRAWING(S) - The drawing shows a block diagram of the device for producing methane by solid-state fermentation.    Ferment devices (1, 19, 20, 21, 22, 23, 24, 25, 26)    Methane liquid output device (5)    Methane liquid backflow device (6)    Methane collection device (7, 25)    Fixed pedestal (8)    Lower end of the pedestal (8)    Movable internal container (9)    Water groove (10)    Movable water sealing cover (11)