NOVELTY - The continuous fermentation device comprises: an enclosure (100) partially filled with a fermentation material (115) and partially filled with an atmosphere of gas above the fermentation material, where the enclosure presents a ceiling (104); a wall (103) separating two compartments having separate atmospheres leaving a passage wall of the material at the bottom; a unit to maintain acidogenic hydrolysis in the first compartment in a direction of displacement of the material upstream of the wall; and a unit to maintain a methanogenesis in a second compartment downstream from the wall.    USE - The device is useful for continuous fermentation such as anaerobic fermentation of waste for reducing the organic matter and producing energy in the form of biogas, where the waste is a household food waste, a waste from sewage treatment plants, and urban, industrial and agricultural wastes.    ADVANTAGE - The device is capable of economically performing the continuous fermentation of the waste in a simple manner.    DETAILED DESCRIPTION - The continuous fermentation device comprises: an enclosure (100) partially filled with a fermentation material (115) and partially filled with an atmosphere of gas above the fermentation material, where the enclosure presents a ceiling (104); a wall (103) separating two compartments having separate atmospheres leaving a passage wall of the material at the bottom; a unit to maintain acidogenic hydrolysis in the first compartment in a direction of displacement of the material upstream of the wall; and a unit to maintain a methanogenesis in a second compartment downstream from the wall. The unit to maintain the acidogenic hydrolysis in the first compartment comprise a unit for maintaining a pH inside the first compartment to be 4.5-6, a unit for the addition of air in the atmosphere of the first compartment, and a unit for controlling a temperature inside the first compartment to be 50 degrees C. The unit to maintain a methanogenesis in the second compartment comprise a unit for controlling temperature inside the second compartment to be 38-40 degrees C. The temperature controlling units comprise a heat exchanger configured to increase the temperature in the first compartment and to reduce the temperature in the second compartment. The unit to maintain acidogenic hydrolysis in the first compartment and the unit to maintain the methanogenesis in the second compartment comprise a set of conduits (108, 109) distributed between the compartments, where the conduits are configured to extend from the ceiling of the enclosure to the fermentation material. The device further comprises: a unit for injecting a compressed gas through the conduits, and a unit for injecting the fermentation material through the conduits; a unit for taking away the fermentation material in the compartments; and a material drain wall configured to reduce the material displaced in the second compartment. The material injection unit injects the fermentation material taken by the unit for taking away the fermentation material.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic sectional view of a continuous fermentation device.    Enclosure (100)    Separation wall (103)    Ceiling (104)    Conduits (108, 109)    Fermentation material. (115)