Methane tank die

The utility model discloses a biomass pool mold, which is mainly composed of a pool wall mold arranged on a pool bottom (10) inside a pool pit (11), a protrusion cover mold arranged on the pool wall mold, a well mold arranged on the protrusion cover mold, a feeding mouth mold connected with the side body of the pool wall mold, a discharging opening mold connected with the side wall of the wall mold and a hydraulic spacing mold arranged on the discharging opening mold, wherein, the pool wall mold is composed of a pool wall external mold and a pool wall internal mold (2) inside the pool wall external mold; and the pool wall external mold is the wall of the pool pit (11). As the utility model mainly uses the space of the pool pit (11) wall and the space inside the pool pit (11) as the external mold to build the biomass pool so that the producing and the installing of most parts of the external mold can be saved; the assembling, disassembling and the transporting of the main internal mold can be easily done and t