Research On Improving Service Life Of MgO-C Bricks For LF Furnace Slag Line By Changing Composition Of LF Slag

The wear mechanism of MgO-C bricks is analyzed particularly based on the working conditions of MgO-C brick for LF slag line.Aimed at wear of MgO-C bricks for LF furnace slag line by reason of LF slag's pulverizing,the cause of LF slag's pulverizing are analyzed and also the effect of pulverization of LF slag on the series damage of Mg-O brick are analyzed.The effect of putting wasted chromite sand into the LF furnace's reduce slag on inhibiting the pulverization of LF slag is investigated.And also its influences to the service life of MgO-C brick for LF slag line and the quality of billets are studied in this paper.The main conclusions as follows:1.Stabilizer with Cr₂O₃ can inhibit the pulvefizating of LF slag effectively.The damage of MgO-C bricks caused by pulverization of LF slag can be lessen and the lifetime of the refining ladle can be increased 17.5%by reason of forning a layer of non-pulverizing slag on the working surface of the MgO-C brick of refining ladle,so the consumption of refractory material can be decreased.2.Pulverizating of LF slag can be inhibited if the additiveamount of stabilizer with Cr₂O₃ be controlled between 4%-5%in testing conditions.The more stabilizer are put,the viscosity of slag willlll get higher and refining effect will get worse. 3.The reason of LF slag's non-pulverized is that Cr₂O₃ dissolving intoα'—C₂S formed a kind of solid solution which prevent the crystalline transformation of fiomα' C₂S toγ—C₂S.4.There is no influences to the chemical composition of the steel liquid and the quality of the internal quality of continuous casting billets when putting the stabilizer with Cr₂O₃ into the slag,and also it can meet the standard.5.The stabilizer is a kind of wasted chromite sand.Recycling and utilization of it can decrease the cost of production.