提高硬线钢LF精炼埋弧效果的生产实践  

Practice of submerged arc process improvement in LF refining for hard wire steel

作　　者：张朝发[1] 郝华强[1] 张宝景[1] 项有兵[1] 李雪松 

机构地区：[1]河北钢铁集团唐钢公司,河北唐山063016 [2]唐山瑞丰钢铁(集团)有限公司,河北唐山063000

出　　处：《炼钢》2015年第5期61-65,共5页Steelmaking

摘　　要：某厂新建65tLF投产后，硬线钢精炼过程埋弧效果差，导致精炼电耗增加，LF吸氮量增加，钢水升温速度比正常炉次低20％。通过硬线钢LF精炼分析，对LF供电模式和造渣工艺进行了优化。LF加热档位采用4档，在化渣阶段采用短弧加热，确保化渣效果和平稳升温，中后期采用中弧或长弧加热。渣料采用石灰、硅灰石和萤石，严格控制加入量800-900kg／炉，电石（0．6～0．9kg／t）少量多次加入，必要时每炉加入2～3袋发泡剂，确保精炼渣的发泡性能。生产实践表明，精炼工艺优化后硬线钢精炼不埋弧炉次明显减少，比例由2．5％降低到0．3％左右；硬线钢精炼平均电耗为60．32kWh／t，电耗平均降低16．92kWh／t，LF工序吸氮质量分数平均降低8．6×10^-6，平均升温速度可达4．06℃／min。The submerged arc performance was not good in the 65 t LF refining process for hard wire steel in certain plant, which resulted in power consumption and w（N） absorption increasing and heating ratio of liquid steel decreasing by 20 %. Through analyzing LF refining for hard wire steel, power supply mode/and slag-forming process were optimized. The fourth voltage grade was used in heating phase. Short arc length was applied to heating in the slag-making stage to ensure slag melting and heating up stable, while middle or long arc length was used in the middle and final stages. The quantity of lime, wollastonite and fluorite was controlled strictly to be 800 - 900 kg per heat. Reductant （0. 6 - 0. 9 kg/t） was put into ladle by little quantity and more frequency in the slag-forming process. If necessary, the blister material was added by 2 -3 bags per heat to ensure the refining slag foaming. The results show that the unburied arc heat percentage for hard wire steel refining decreases from 2.5 % to 0.3 %. The power consumption in hard wire steel refining is 60.32 kWh/t, which decreases by 16. 92 kWh/t. The mass fraction of N absorption in LF process decreases by 8. 6×10^-6, and the heating rate of liquid steel is 4. 0b ℃/min.

关 键 词：硬线钢 LF精炼 埋弧效果 电耗 

分 类 号：TF769.2[冶金工程—钢铁冶金]