The rotational jet and local oxygen enrichment can improve the mixing of oxygen and pulverized coal, but the effect of coal injection is weak on the whole flow field in blowpipe.
结果表明，氧-煤喷枪的漩流、富氧率等仅在氧枪出口的有限区域内对流场有较大的影响；
2
With the price growth of coal, it is necessary to recalculate the economic efficiency of oxygen-riched coalinjection.
随着煤炭价格上涨，富氧多喷煤的经济效益要重新计算。
3
Calculation and plotting methods of BF operation line without coalinjection are modified, and calculation formulae of BF operation line with oxygen enrichment and high PCI rate are deduced.