Preparation and characterization of regenerated MgO–CaO refractory bricks sintered under different atmospheres
来源期刊:International Journal of Minerals Metallurgy and Materials2014年第12期
论文作者:Gui-bo Qiu Xiang Li Min Guo Mei Zhang
文章页码:1233 - 1240
摘 要:Regenerated Mg O–Ca O brick samples containing 80wt%, 70wt%, and 60wt% Mg O were prepared using spent Mg O–Ca O bricks and fused magnesia as raw materials and paraffin as a binder. The bricks were sintered at 1873 K for 2 h under an air atmosphere and under an isolating system. The microstructure, mechanical properties at room temperature, and hydration resistance of the regenerated samples were measured and compared. The results indicated that the isolating sintering generated a strongly reducing atmosphere as a result of the incomplete combustion of paraffin, and the partial oxygen pressure was approximately 6.68 × 10–7 Pa. The properties of the regenerated bricks sintered under air conditions were all higher than those of the bricks sintered under a reducing atmosphere. The deterioration of the bricks was a result of Mg O reduction and a decrease in the amount of liquid phase formed during sintering under a reducing atmosphere.
Gui-bo Qiu1,Xiang Li1,Min Guo1,Mei Zhang1
1. Beijing Key Lab of Green Recycling and Extraction of Metals, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing
摘 要:Regenerated Mg O–Ca O brick samples containing 80wt%, 70wt%, and 60wt% Mg O were prepared using spent Mg O–Ca O bricks and fused magnesia as raw materials and paraffin as a binder. The bricks were sintered at 1873 K for 2 h under an air atmosphere and under an isolating system. The microstructure, mechanical properties at room temperature, and hydration resistance of the regenerated samples were measured and compared. The results indicated that the isolating sintering generated a strongly reducing atmosphere as a result of the incomplete combustion of paraffin, and the partial oxygen pressure was approximately 6.68 × 10–7 Pa. The properties of the regenerated bricks sintered under air conditions were all higher than those of the bricks sintered under a reducing atmosphere. The deterioration of the bricks was a result of Mg O reduction and a decrease in the amount of liquid phase formed during sintering under a reducing atmosphere.
关键词: