NOVELTY - The device comprises material feeding tube connected with an inner cylinder tank and an outer cylinder tank from inside to outside along coaxial line. An upper part of the material feeding tube extends out of a column container, and is equipped with two-way valve I. A lower part of the material feeding tube extends to a cylinder in distance of 20-40 cm. The outer cylinder tank is provided with a heat preservation layer. A bottom part of the outer cylinder tank is cone-shaped. A conical top part of the outer cylinder tank is provided with a biogas residue discharge pipe.    USE - The device is useful for dry anaerobic fermentation of organic household rubbish (claimed).    ADVANTAGE - The device is stable and compact in structure, realizes split-phase anaerobic fermentation, and occupies small floor area.    DETAILED DESCRIPTION - The device comprises material feeding tube connected with an inner cylinder tank and an outer cylinder tank from inside to outside along coaxial line. An upper part of the material feeding tube extends out of a column container, and is equipped with two-way valve I. A lower part of the material feeding tube extends to a cylinder in distance of 20-40 cm. The outer cylinder tank is provided with a heat preservation layer. A bottom part of the outer cylinder tank is cone-shaped. A conical top part of the outer cylinder tank is provided with a biogas residue discharge pipe whose upper part is provided with a two-way valve II. Upper ends of the inner cylinder tank and the external cylinder tank are sealed. A bottom part of the inner cylinder tank is provided with first reaction area. A cavity is formed in a second reaction area. Volume ratio of the first reaction area and the second reaction area is 2-7.4. A top part of the first reaction area is connected with a gas discharge pipe II. The second reaction area is provided with a gas discharge pipe I. An upper part of the gas discharge pipe II is provided with the two-way valve III. The gas discharge pipe I is provided with two-way valve VI. An acid liquid exit is arranged in the inner cylinder tank at distance of 10-20 cm. The bottom part of the second reaction area is provided with an annular water distribution device, which is provided with 3 holes. A side of the second reaction area is provided with a biogas circulation reflux tube whose upper end is connected with biogas slurry exit. A lower end of the circulation reflux tube is connected with a water distributing device. The biogas circulation reflux tube is connected with a peristaltic pump through the two-way valve II. Another side of the second reaction area is connected at the bottom part of the vertical liquid discharge pipe whose upper part is provided with biogas liquid discharge ports. An INDEPENDENT CLAIM is included for dry anaerobic fermentation of organic household rubbish using device.