高炉风口氢煤共喷的数值模拟研究

Study on Numerical Simulation of Hydrogen Coal Co-injection in Blast Furnace Tuyere

氢气是一种无碳的清洁能源,具有良好的还原性,可替代部分高炉喷吹煤粉。向风口喷注氢气可以降低煤比,减少高炉碳排放。基于数值模拟方法,建立高炉风口喷氢的三维稳态模型,研究喷注不同含量的氢气与氧气对煤粉燃烧和回旋区状态特性的影响。模拟结果表明,氢气燃烧产生的热量可以促进煤粉脱挥发,但氢气燃烧会消耗大量氧气,降低挥发分周围的氧气浓度,影响挥发分的燃烧效率。当高炉注氢时,氧气消耗速率加快,CO_(2)产生量明显下降,H_(2)、水蒸气生成量增加,但CO含量从42.5%下降至38.7%,煤粉燃尽率从69.8%降低至66.4%。当富氧率增加2%时,风口出口平均温度提高22 K,煤粉燃尽率上升2.3%,CO产生量由38.7%提高到40.0%。研究成果可为高炉氢煤共喷操作提供理论指导和数据支持。

Hydrogen is a carbon free clean energy source with good reducibility,which can replace some blast furnace coal powder injection,and injecting hydrogen gas into the tuyere can reduce the coal ratio and decrease the carbon emissions of the blast furnace.Based on numerical simulation methods,a three-dimensional steady-state model of hydrogen injection into blast furnace tuyere is established to study the effects of injecting different contents of hydrogen and oxygen on coal powder combustion and swirling zone state characteristics.The simulation results indicate that the heat generated by hydrogen combustion can promote coal powder devolatilization,but hydrogen combustion consumes a large amount of oxygen,reducing the oxygen concentration around volatile matter and affecting the combustion efficiency of volatile matter.When hydrogen is injected into the blast furnace,the oxygen consumption rate increases,the amount of CO_(2) produced significantly decreases,the amount of H_(2) and steam generated increases,but the CO content decreases from 42.5% to 38.7%,and the coal powder burnout rate decreases from 69.8% to 66.4%.When the oxygen enrichment rate increases by 2%,the average temperature at the outlet of the tuyere increases by 22 K,the combustion rate of coal powder increases by 2.3%,and the amount of CO produced increases from 38.7% to 40.0%.The research results provide theoretical guidance and data support for the operation of hydrogen coal co-injection in blast furnaces.