Effect of Al2O3 content on alkali holding capacity of blast furnace slag and related liquids
Alkali circulation phenomena create complex problems in the blast furnace leading to lowered production efficiency. Improving alkali holding capacity of liquid slags evolving from the cohesive zone and finally forming the blast furnace slag will reduce these problems. Effect of Al2O3 content on alkali holding capacity of synthetic slags in a part of system SiO2-CaO- Al2O3-K2O-FeO and modified blast furnace slag were tested with laboratory experiments. Slag samples with constant K2O content, constant or no FeO addition, and varied Al2O3 contents, were heated in graphite test tubes at 1460 °C for 90 minutes in Ar gas atmosphere containing a small amount of CO gas. After rapid quenching of the liquids the usually homogenous glass samples were analyzed with SEM. The amount of K2O retained was taken for the measure of the alkali holding capacity. Samples with high basicity (CaO/SiO2 ratio) had lower alkali holding capacity than those with lower basicity. Increasing the Al2O3 content of the slags was observed to increase the alkali holding capacity for all slags tested in the experiments. Thermodynamic calculations also indicated that higher Al2O3 contents will reduce alkali gasification from the liquid slags concerned. Increasing the reduction degree of the iron burden in solid state and increasing the Al2O3 content of the iron burden can decrease the alkali circulation related problems in the blast furnace.
Blast furnace slag alkali holding capacity laboratory tests thermodynamic calculations
Pekka A. TANSKANEN Timo PAANANEN Eetu-Pekka HEIKKINEN
University of Oulu, Laboratory of Process Metallurgy, FIN-90014 University of Oulu, Finland Rautaruukki Oyj, Ruukki Production, FIN-92101 Raahe, Finland
国际会议
Ninth International Conference on Molten Slags,Fluxes and Salts(第九届国际熔渣、溶剂与熔盐学术会议 MOLTEN12)
北京
英文
1-8
2012-05-27（万方平台首次上网日期，不代表论文的发表时间）