Characteristics of Metallurgical Waste Slag and Its Heating Behavior in A Microwave Field

摘要

Four kinds of typical metallurgical waste slags were characterized with their chemical composition, crystalline phases, microstructure and thermal behavior. The heating behaviors of these slags in a microwave field were also examined. The results show that there is a high content of CaO in these waste slags. When the metallurgical waste slags were heated from room temperature to 1300°C, the weight loss of Blast Furnace (BF) slag and ladle furnace (LF) refining slag are only 2.25% and 0.9%, respectively, while the weight loss of Basic Oxygen Furnace (BOF) slag and electric arc furnace (EAF) slag are more than 5%. These metallurgical waste slags have a good absorption capacity for the microwave irradiation, the absorption capacity of microwave decreases in the order of converter slag > EAF carbon steel slag > baste furnace slag. In addition, the temperature-rising rates of the metallurgical waste slags increase with the microwave power and the quality or the particle sizes of slags. Furthermore, the crystalline phases of treated slag with microwave are similar with that of the untreated metallurgical slag. A number of internal cracks in particles of metallurgical slag can be found or extended after microwave treatment.