基于分析理论,建立高炉喷吹焦炉煤气分析模型,系统地研究焦炉煤气喷吹量对高炉损失、热力学完善度和效率的影响,提出高炉喷吹焦炉煤气操作条件下能量利用再优化的途径。研究结果表明:高炉的输入主要为燃料的化学和热风物理;输出主要为铁水的物理和化学、高炉煤气化学以及内部损失;与未喷吹操作相比,当喷吹量为11.89 m3/s时,内部损失和总损失分别降低26.38%和3.98%,外部损失升高2.11%,喷吹焦炉煤气对减少高炉内部的损失更为明显;喷吹焦炉煤气后,高炉的热力学完善度由90.23%上升到92.65%,效率由53.39%上升到54.25%,能量利用的质量得到提高;喷吹焦炉煤气后,铁水和炉渣的物理和化学相对稳定,吨铁炉顶煤气的化学由4.60增加到4.97 GJ,应加强这部分的利用。
Exergy analytical model of blast furnace with coke oven gas (COG) injection was established based on the theories of exergy analysis. Effects of COG injection volume on the exergy loss, thermodynamic perfection degree and exergy efficiency of blast furnace were researched systematically, and the ways of energy utilization re-optimization of blast furnace with COG injection were put forward. The research results are shown as follows: the input exergy of blast furnace is mainly chemical exergy of fuel and physical exergy of hot blast, and the output exergy is mainly physical exergy and chemical exergy of hot metal, chemical exergy of top gas and internal exergy loss. Compared with no COG injection, internal exergy loss and total exergy loss are decreased by 26.38% and 3.98% respectively while external exergy loss is increased by 2.11% for 11.89 m3/s COG injection. Namely, the injection of COG is more obvious to reduce internal exergy loss of blast furnace. With the increase of COG injection, the thermodynamic perfection degree is increased from 90.23% to 92.65%, and the exergy efficiency is increased from 53.39% to 54.25%, which shows the improvement of energy utilization quality. With the increase of COG injection, the physical exergy and chemical exergy of hot metal and hot slag are relatively stable. The chemical exergy of top gas per ton of hot metal is increased from 4.60 to 4.97 GJ. Therefore it is import.ant to strengthen the utilization of top gas.