System for semi-wet treating furnace slag, recovering waste heat and generating power and method thereof

A system for semi-wet treating furnace slag, recovering waste heat and generating power comprises a furnace slag treatment system, a waste heat recovery system (300) and a waste heat power generation system (500). The furnace slag treatment system is a furnace slag semi-wet treatment system (100), in which molten blast furnace slag (101) is cooled by high pressure water mist, mechanically crushed by a crushing device (106), and then treated into raw material for producing cement. The waste heat recovery system (300), in multistage, recovers and stores waste heat produced in the furnace slag semi-wet treatment system (100). The waste heat power generation system (500) generates power from heat energy stored in the multistage heat energy storage system. A method for semi-wet treating furnace slag, recovering waste heat and generating power is also provided.