The invention relates to a device for preparing
hydrogen-rich gas by gasifying a
biomass under the
catalysis of high-temperature
metallurgical slag particles and a method. The device comprises a downer reactor, a high-temperature
slag particle storage chamber, a spiral
biomass raw material feeder, a separator, a steam generator and a
hydrogen-rich gas collector, wherein the high-temperature
slag particle storage chamber and the spiral
biomass raw material feeder are located above the downer reactor and are communicated with the top of the downer reactor; the separator is located below the downer reactor and is communicated with the bottom of the downer reactor; and the steam generator and the
hydrogen-rich gas collector are located at two sides of the downer reactor and are respectively communicated with the downer reactor. The method in which the device is applied comprises the steps of respectively adding high-temperature
metallurgical slag particles, biomass raw materials and steam into the downer reactor through a rotary
molten slag granulating device, the spiral biomass
raw material feeder and the steam generator; carrying out gasification reaction on the biomass raw materials under the
catalysis of the high-temperature
metallurgical slag particles to generate hydrogen-rich gas; and storing the hydrogen-rich gas into the hydrogen-rich gas collector. By using the method,
waste heat of metallurgical
slag is recycled in a
chemical energy way, so that the
recovery rate of the
waste heat is relatively high, and the problems of low
waste heat recovery rate and low
recovery quality of a dry-method metallurgical slag treatment process are solved.