NOVELTY - Full-automatic methane tank comprises fermentation tank, material inlet pipe, and manure storing pit. The material inlet pipe is connected with lower front side of fermentation tank. The lower part of rear side of fermentation tank is connected with bottom of manure storing pit via material outlet pipe. The upper rear side of fermentation tank is connected with upper part of manure storing pit via overflow pipe. The rear side of manure storing pit is provided with slag outlet pipe.    USE - Full-automatic methane tank.    ADVANTAGE - The full-automatic methane tank can automatically discharge slag material of different fermentation scales. It produces gas at high yield and at high efficiency. It can automatically stir for breaking upper layer floating shell and provides abundant and stable fermentation.    DETAILED DESCRIPTION - Full-automatic methane tank comprises fermentation tank, material inlet pipe, and manure storing pit. The material inlet pipe is connected with lower front side of fermentation tank. The lower part of rear side of fermentation tank is connected with bottom of manure storing pit via material outlet pipe. The upper rear side of fermentation tank is connected with upper part of manure storing pit via overflow pipe. The rear side of manure storing pit is provided with slag outlet pipe. The outlet of slag outlet pipe is provided with pipe port blocking piece. The lower pipe port of material outlet pipe is close to center of bottom of fermentation tank. The upper pipe port of material outlet pipe is higher than bottom of manure storing pit. The diameter of material outlet pipe is greater than that of overflow pipe. The outlet horizontal position of slag outlet pipe port of manure storing pit is lower than outlet of overflow pipe. The distance between lower pipe port of material outlet pipe and lowest part of fermentation tank is 20-30 cm. The diameter of material outlet pipe is 20-30 cm. The upper pipe port of material outlet pipe is higher than bottom of manure storing pit by 10-20 m and diameter of overflow pipe is 11 cm. The material outlet pipe has lean angle of 40-45 degrees .    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of full-automatic methane tank.