The invention discloses device and method for preparing
hydrogen-rich gas by gasifying
biomass. The device mainly comprises a
pyrolysis reactor, a
combustion reactor, a gasification reactor, a gas-
solid separator, a
gas cooler and an
exhaust heat boiler, wherein the
pyrolysis reactor is arranged in the
combustion reactor. In a process course, the
biomass is firstly pyrolyzed in the
pyrolysis reactor to generate pyrolysis gas and
coke, the pyrolysis gas is directly combusted to provide heat for
biomass pyrolysis and gasification, and the
coke is subjected to gasification reaction with
water vapor to obtain the
hydrogen-rich gas. The device and method disclosed by the invention realize the separation of the pyrolysis process and
coke gasification process of the biomass and can be used for displacing the
hydrogen contained in the
water vapor by sufficiently utilizing
fixed carbon contained in the biomass. According to the device and method, the obtained hydrogen-rich gas mainly contains H2, CO2 and a small amount of CO, so that the conventionally gasified hydrogen-rich gas product is prevented from being mixed with low-carbon
hydrocarbon gas and
tar, and the subsequent decontamination and purification utilization are simple, convenient and economic.