Synchronization technology of ensuring biomasses to be resourceful and chromium slag to be harmless by utilizing steel slag waste heat

The invention relates to a method of synchronously treating liquid steel slag, chromium slag and biomasses. According to the method, by heating the steel slag, gasifying the biomasses and utilizing chromium slag as hazardous wastes and other catalysts to catalyze and crack biomasses at high temperature, the biomasses are more completely converted to low-molecule high-temperature energy gas under the condition of gasifying water vapor, so that coking on the surface of the chromium slag is prevented; and meanwhile, by heating the chromium slag with utilization of the high-temperature energy gas and reducing hexavalent chromium in the chromium slag into trivalent chromium, the energy gas is cooled as well, and CO2 and Cl in the energy gas are absorbed by alkaline substances in the chromium slag. According to the process, when the chromium slag is treated to be harmless, and the steel slag is cooled, the energy is greatly saved, and the high-grade energy gas is also obtained.