无喷氧条件下氢基竖炉的生产

PRODUCTION OF HYDROGEN-BASED SHAFT FURNACE WITHOUT OXYGEN INJECTION

张宣科技氢基竖炉在无喷氧条件下生产时,由于没有喷氧部分燃烧的热量补充,竖炉入口工艺气温度下降了90℃,CH_(4)重整效果变差,工艺气中H_(2)和CO含量大幅度降低,CH_(4)含量大幅度升高,工艺气还原能力减弱,还原效果变差,导致DRI产量、金属化率、抗压强度下降,焦炉煤气单耗和DRI含碳量升高。通过采取一系列措施,在保证不触发加热炉连锁停机的前提下尽可能提高加热炉出口温度,加热炉出口温度控制较喷氧正常生产时提高了15℃,尽可能维持竖炉还原区较高温度及热量水平,保证CH_(4)重整效果;通过降低装、排料速度,提高炉顶温度控制水平,顶温控制较正常生产时提高了50℃,延长了原料还原停留时间,保证还原效果;提高加湿率,控制DRI含碳量。生产的DRI产量虽有所降低,焦炉煤气单耗升高,冶炼经济性下降,但DRI金属化率93%以上、含碳量4%以下、抗压强度大于600 N/球,完全满足电炉炼钢的配加要求。

During the production of Zhang Xuan Technology's hydrogen based vertical furnace without oxygen injection,due to the lack of heat supplementation from oxygen injection combustion,the inlet process gas temperature of the vertical furnace decreased by 90℃,the CH 4 reforming effect deteriorated,the H_(2)and CO content in the process gas decreased significantly,the CH_(4)content increased significantly,the reduction ability of the process gas weakened,the reduction effect deteriorated,resulting in a decrease in DRI production,metallization rate,compressive strength,and an increase in coke oven gas consumption and DRI carbon content.By taking a series of measures,the outlet temperature of the heating furnace is increased as much as possible without triggering the chain shutdown of the heating furnace.The outlet temperature of the heating furnace is controlled to be 15℃higher than that during normal oxygen injection production,and the high temperature and heat level in the reduction zone of the vertical furnace are maintained as much as possible to ensure the CH_(4)reforming effect;By reducing the loading and discharging speed and improving the temperature control level of the furnace top,the top temperature control has been increased by 50℃compared to normal production,prolonging the residence time of raw material reduction and ensuring the reduction effect;Improve humidification rate and control DRI carbon content.Although the production of DRI has decreased,the unit consumption of coke oven gas has increased,and the smelting economy has declined,the DRI metallization rate is over 93%,the carbon content is below 4%,and the compressive strength is greater than 600 N/ball,fully meeting the blending requirements of electric furnace steelmaking.