NOVELTY - Heat preservation methane tank comprises movable cover plate (1), arc cover (2), upper tank wall (3), T-shaped head (4), T-shaped groove (5), lower tank wall (6), reinforcing rib (7), tank bottom (8) and directional block (9), where each component of the utility is a plate connecting structure.    USE - The heat preservation methane tank is useful for processing waste agricultural film (claimed).    ADVANTAGE - The tank has anti-leakage property, provides high yield, is inexpensive, and convenient for transport and can be easily utilized for long period of time.    DETAILED DESCRIPTION - Heat preservation methane tank comprises movable cover plate (1), arc cover (2), upper tank wall (3), T-shaped head (4), T-shaped groove (5), lower tank wall (6), reinforcing rib (7), tank bottom (8) and directional block (9), where each component of the utility is a plate connecting structure. The lower end of the movable cover plate is arranged with the T-shaped head. The upper end face of the arc cover is arranged with the T-shaped groove corresponding to the T-shaped head and both side ends of the upper tank wall. The lower tank wall and the tank bottom are respectively arranged with T-shaped heads and both side end faces of the upper tank wall. The lower tank wall and the tank bottom are respectively arranged with T-shaped groove corresponding to the T-shaped head and one end of the T-shaped head is connected with directional block. The top portion of the T-shaped head is arranged with a locating plane. The bottom of each T-shaped groove is arranged with groove, the movable cover plate, the arc cover, the upper tank wall, the lower tank wall and the tank bottom orderly connected with each corresponding T-shaped groove by each T-shaped head.    DESCRIPTION OF DRAWING(S) - The drawing shows schematic view of heat preservation methane tank.    Cover plate (1)    Arc cover (2)    Upper tank wall (3)    T-shaped head (4)    T-shaped groove (5)    Lower tank wall (6)    Reinforcing rib (7)    Tank bottom (8)    Directional block (9)