NOVELTY - The method involves providing lower-temperature carbon into moving bed carbonization furnace (3). Combustible gas and gasification gas are provided to fuel gas heater (9), internal combustion engine generating system (16), and steam generator (7). High temperature carbon is entered into fluidized bed carbohydrate reaction furnace (4) to generate the primary hydrogen-rich gas by cyclone separator (17) and condenser (5). Hydrogen purifying device (6) is used for purifying hydrogen by normal temperature explosion-proof fan (15), to obtain the hydrogen with purity of more than 99.99%.    USE - Method for preparing high-purity hydrogen from biomass.    ADVANTAGE - The heat energy required by the whole production line can be provided, and electricity can be generated by gas to provide electric energy required by all power equipment, so that zero consumption of external power can be ensured. The defects of low yield and low biomass charcoal reaction activity of carbonization process can be avoided, and the reaction activity of the biomass charcoal can be improved while ensuring the high yield of biomass charcoal by coupling slow low-temperature carbonization reaction and fast high-temperature carbonization reaction. The water-charcoal reaction can be accelerated and the energy consumption in the water-charcoal reaction process can be reduced. The content of hydrogen of the generated primary hydrogen-rich gas can be over 85%, and can even be more than or equal to 99.99% after purification of hydrogen purification device.    DETAILED DESCRIPTION - The method involves conveying biomass and hot air by conveyor belt to down-suction fixed bed gasification furnace. High temperature gasification gas is generated in gasification reaction and sent to furnace. Biomass is heated. An INDEPENDENT CLAIM is included for a device for preparing high-purity hydrogen from biomass.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the device for preparing high-purity hydrogen from biomass.    Moving bed carbonization furnace (3)    Fluidized bed carbohydrate reaction furnace (4)    Condenser (5)    Hydrogen purifying device (6)    Steam generator (7)    Fuel gas heater (9)    Normal temperature explosion-proof fan (15)    Internal combustion engine generating system (16)    Cyclone separator (17)