高镁铝酸钙型预熔精炼渣配加合成渣以及Al对低碳钢深脱硫的研究

A Study on Deep Desulphurization of Low Carbon Steel by High Magnesium Calcium Aluminate Premelted Refining Slag Combined with Synthetic Slag and Adding Al

用10 kg感应炉进行了20%～40%高镁铝酸钙预熔渣(/%:5SiO_2、37CaO、42Al_2O_3、13MgO、3FeO)配加60%～80%合成渣(/%:10SiO_2、61CaO、25Al_2O_3、4MgO)及加5～10g/kg Al对初始(74～167)×10^(-6)[S]的低碳钢(/%:0.06C、0.20Si、1.20Mn、0.020Nb、0.015Ti)的深脱硫试验。结果表明,钢液硫含量在精炼10 min内就可到达最低值,精炼过程随着钢液氧活度逐渐升高而渣硫化物容量逐渐降低,渣钢硫分配比减小,钢液有一定的回硫;较大的铝加入量、较低的初始硫含量和较大的渣硫化物容量有利脱硫反应的进行,也可以抑制钢液回硫;20%高镁铝酸钙预熔渣+80%合成渣脱硫效果较好,控制精炼渣成分(/%):50～60CaO、5～7MgO、28～32Al_2O_3、～8SiO_2、Al加入量3 g/kg,钢中硫含量可降至0.0016%。

The deep desulphurization test on low carbon steel （/% ： O. 06C, 0. 20Si, 1.20Mn, 0. 020Nb, O. 015Ti） with initial （74 - 167）× 10-6[ S] is carried out by 20% ~ 40% high magnesium calcium aluminate premelted slag （/% ： 5SIO2, 37CAO, 42A1203 , 13MgO, 3FeO） combined with 60% ~ 80% synthetic slag （/% ： 10SiO2 , 61CaO, 25A1203 , 4MgO） and adding 5 ~ 10 g/kg A1 in a 10 kg induction furnace. Results show that during refining the sulfur content in liquid decreases to lowest value in 10 rain, with gradually increasing oxygen activity in liquid and decreasing sulfide capacity of slag in refining process the sulfur distribution ratio between slag and liquid decreases and the phenomenon of definite resulphurization in liquid occurs; the larger aluminum addition, lower initial sulfur content in liquid and higher sulfide capacity of slag are favorable for desulphurization reaction and to inhabit resulphurization; the desulphurization effect of 20% high magnesium calcium aluminate ＋ 80% synthetic slag is better and with controlling refining slag ingredient （/%） 50~60CaO, 5 ~ 7MgO, 28 - 32A1203 , ~ 8SiO2 and adding 3 g/kg A1 the sulfur content in steel could decrease to 0. 001 6%.