高碱度精炼渣组分变化对渣系液相量的影响

Influence of Composition Variation of High Basicity Refined Slag on Slag Liquid Phase Region

在实际生产中,当高碱度精炼渣的造渣量较大时,会存在精炼渣结壳现象。利用FactSage热力学软件,以高碱度精炼渣为标准,研究精炼过程中组分变化对渣系液相区的影响规律。结果表明,当温度在1500℃~1600℃时,增加MgO含量和适量的Al_(2)O_(3)可以明显缩小渣系液相区的面积;增加B_(2)O_(3)和CaF_(2)的含量会增大渣系液相区的面积。由于MgO有利于炉衬的保护,Al_(2)O_(3)含量可以抑制精炼渣中一些高熔点物质析出,因此建议MgO用量为7%;Al_(2)O_(3)添加量在26%左右。此外,由于B_(2)O_(3)加入量在达到某一值后,渣系会析出镁铝尖晶石,CaF_(2)会引起氟污染并侵蚀炉衬,不利于连铸生产,因此建议CaF_(2)与B_(2)O_(3)的添加量分别为7%和5%。

In practical production,when the high basicity refining slag slagging amount is larger,refining slag crust will take place.Taking high basicity refined slag as the standard,the influence of composition change on the liquid phase region of slag was studied by using the method of Factsage thermodynamics software.The results show that with the increase of MgO content,the amount of MgO is favorable for the protection of the lining,so the recommended dosage of MgO is 7%.Whenω(Al_(2)O_(3))increases from 22%to 30%,and the slag liquid phase is at 1500℃,the content of Al_(2)O_(3) is about 26%,taking into account the increase of Al_(2)O_(3) content can reduce the slag some high melting point material precipitation.With the increase of CaF_(2) and B_(2)O_(3) content,the slag liquid phase the effect of B_(2)O_(3) is more obvious,but CaF_(2) can cause fluorine pollution and erosion of the lining.When B_(2)O_(3) is added,the slag will precipitate the Mg-Al spinel,which is not conducive to the continuous casting.Therefore,CaF_(2) and B_(2)O_(3) of the additions are 7%and 5%,respectively.