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如何防止精炼过程钢液的回磷?

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正确答案:

精炼过程回磷主要是因为渣中的(P2O5)被还原而进入钢液,所以必须降低入LF渣中的(P2O5),渣中的(P2O5)主要是初炼炉下渣所带来的。转炉或电炉终点炉渣中的(P2O5)较高,如出钢带入钢包内的炉渣过多,由于钢包内钢水的对流作用及造还原渣,渣中的(P2O5)会还原而进入钢液中,所以要减少下渣量,电弧炉炼钢由于采用偏心底出钢技术及留钢留渣操作,可基本做到不带下渣,即所谓的无渣出钢。而转炉下渣却难以控制,虽然采用了挡渣球、机械挡渣塞、气动挡渣及电磁感应传感器法挡渣,仍不可避免地会有下渣带入,但下渣量相比以前大幅度降低,下渣入钢包后,要立即对下渣进行处理。

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