Numerical Analysis of Blast Furnace Performance Under Charging Iron-Bearing Burdens With High Reducibility

The reducibility of iron-bearing burdens was emphasized for improving the operation efficiency of blast furnace. The blast furnace operation of charging the burdens with high reducibility has been numerically evaluated using a multi-fluid blast furnace model. The effects of reaction rate constants and diffusion coefficients were investigated separately or simultaneously for clarifying the variations of furnace state. According to the model simulation results, in the upper zone, the indirect reduction of the burdens proceeds at a faster rate and the shaft efficiency is enhanced with the improvement under the conditions of interface reaction and intra-particle diffusion. In the lower zone, direct reduction in molten slag is restrained. As a consequence, CO utilization of top gas is enhanced and the ratio of direct reduction is decreased. It is possible to achieve higher energy efficiency of the blast furnace, and this is represented by the improvement in productivity and the decrease in consumption of reducing agent. The use of high-reducibility burdens contributes to a better performance of blast furnace. More efforts are necessary to develop and apply highreducibility sinter and carbon composite agglomerates for practical application at a blast furnace.

Non-isothermal reduction process analysis of iron-bearing burden with charging iron coke hot briquette under simulated blast furnace conditions

Highly reactive iron coke hot briquette(ICHB)prepared by carbonizing the agglomerate of iron-bearing substance and blended coals is regarded as an alternative fuel to mitigate carbon emission and energy consumption of blast furnace.Simultaneously,the reduction process of iron-bearing burden is extremely crucial for blast furnace smelting.The effects of ICHB on the non-isothermal reduction process of iron-bearing burden with different reduction properties were thus experimentally studied under the conditions of simulated blast furnace lump zone(below 1100°C),and the related mechanism was discussed and analyzed.The results showed that the non-isothermal reduction process of iron-bearing burden is promoted by adding ICHB.As the charging ratio of ICHB is increased from 0%to 30%,the reduction degree of pellet is increased from 22.91%to 36.62%,but the increased amplitude is leveled off.Furthermore,the reduction degree of sinter is raised from 35.10%to 93.33%.It is also indicated that the promotion effect of ICHB on the non-isothermal reduction of iron-bearing burden depends on the reduction property of burden.Compared with the burden with poor reduction performance(such as pellet 1),the promotion is more significant for the burden with good reduction property(such as sinter 1)since the reduction reaction of iron oxide in iron-bearing burden and the gasification of carbon in ICHB are remarkably reinforced each other.The practical application of ICHB in blast furnace should be utilized with highly reductive iron-bearing burden.

FAAS连续测定高炉炉料中氧化钾、氧化钠和锌

分别选用氧化钾、氧化钠、锌的次灵敏线769.9、330.3和307.6 nm,以空气-乙炔火焰原子吸收光谱法对高炉炼铁炉料用含铁尘泥中高含量的氧化钾、氧化钠、锌的测定进行了研究,通过实验得到仪器最佳工作条件,从而建立了火焰原子吸收光谱法测定高炉炼铁炉料用含铁尘泥中高含量的氧化钾、氧化钠、锌的分析方法。本方法准确、简便、快速。用该法对已知结果结晶器保护渣、除尘灰、消泡剂等试样进行了测定,测定结果与ICP-AES法测定结果相符。

有害元素对高炉炉况的影响

介绍了石钢在入烧料中配加大量除尘会后,K,Na,Zn等有害元素含量增加,在系统中循环,无法外排,对高炉炉况产生的恶劣影响。对炉况发生变化前的一些征兆及采取措施后炉内有害元素的变化趋势进行了分析。

高炉煤气干法除尘节能新途径

为干法除尘煤气升温提出了一个新方案。分析了升温与增加余压发电出力关系，通过煤气加热升温可以增加电能回收，使炉顶高温得以有效利用；干法除尘煤气具有低水分、高热值特点，因此同样具有节能意义，但是在为防腐蚀所进行碱洗时，“干”煤气又变“湿”煤气，使优点丧失，提出了解决问题的新思路。