Effect of oxygen enrichment on flow field, temperature, concentration distribution, emission, and fuel economy has been studied inside a pilot-scale Rotary Hearth Furnace (RHF) for two separate conditions with or without varying the fuel amount. In varying fuel condition (when amount of fuel is reduced with oxygen enrichment to maintain the flame temperature constant), the fuel consumption was reduced by 14.9 pct, when oxygen enrichment in increased from 21 to 35 pct. Under this condition, the high-temperature zone showed a shift, more towards the upstream of the flame with an increase in the oxygen enrichment and led to a decrease in heat transfer towards the bottom part of the furnace, not desirable for pellet reduction at the bottom. In case of constant fuel (fuel volume remaining constant irrespective of oxygen enrichment), the high-temperature zone spreads away from the burner and such shift progressively becomes more with an increase in the oxygen enrichment. More importantly, in this case, efficiency heat transfer from the top to the bottom of the furnace increased with oxygen enrichment. Specific CO2emission per ton of DRI produced showed a sharp decrease with an increase in oxygen enrichment, mainly in fuel varying condition. In contrast, the emission remained more or less similar in fuel constant condition.

中文翻译：

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富氧对中试转底炉内流场、温度和气体浓度分布的影响

富氧对流场、温度、浓度分布、排放和燃料经济性的影响已在中试规模的转底炉 (RHF) 内进行了研究，在两种不同的条件下，无论是否改变燃料量。在不同的燃料条件下（当通过富氧减少燃料量以保持火焰温度恒定时），当富氧从 21% 增加到 35% 时，燃料消耗减少了 14.9%。在这种情况下，高温区显示出移动，更多地向火焰上游移动，富氧量增加，导致向炉底传热减少，不利于球团还原。底部。在燃料恒定的情况下（燃料量保持恒定，与富氧无关），高温区远离燃烧器，随着富氧的增加，这种偏移逐渐变大。更重要的是，在这种情况下，从炉顶到炉底的传热效率随着氧气的富集而增加。生产的每吨直接还原铁的特定 CO2 排放量随着氧气浓度的增加而急剧下降，主要是在燃料变化的情况下。相比之下，排放在燃料恒定条件下或多或少保持相似。主要是在燃料变化的条件下。相比之下，排放在燃料恒定条件下或多或少保持相似。主要是在燃料变化的条件下。相比之下，排放在燃料恒定条件下或多或少保持相似。