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从中国两座高炉风口回旋区取出煤粉样研究表明:当喷煤量达到140kg/t.HM(占燃料总量的27％)时,虽然煤早在直吹管内就开始了挥发和燃烧,但煤在回旋区内并不能完全燃烧。不过这一不完全燃烧还不破坏高炉的顺行。 用两种方法在实验室内进行了粉煤燃烧动力学研究,一种是用电阻丝加热鼓风,另一种则用等离子火炬。发现煤的燃烧率在40～80μm范围内几乎和煤的粒度大小成反比,它随着风温的提高而提高,直到1475℃;富氧到40％仍很有效。当空气过剩系数降到1.2～1.3以下则煤的燃烧率突然下降。当鼓风旋转时燃烧加快。 滴落区内,炉渣和煤灰或未燃尽的半焦的混合并不是提高喷煤量的控制因素。喷煤枪位置、角度和形状影响气固两相分布的研究表明:这些因素对喷入煤粒在助燃空气流中的均匀分布有显著影响,这一研究是采用激波管和纹影法完成的。
Pulverized coal samples taken from two blast furnace tuyeres in China showed that when the amount of coal injected reached 140 kg / t.HM (27% of the total fuel), although coal began to volatilize and combust as early as inside the blowpipe, However, the coal does not completely burn in the racecourse. However, this incomplete combustion does not destroy the blast furnace. Two methods were used to study the kinetics of pulverized coal combustion in the laboratory. One was to heat the blast with a resistance wire and the other to use a plasma torch. Found that the combustion rate of coal in the range of 40 ~ 80μm and coal size is almost inversely proportional to the size, it increases with the air temperature increased until 1475 ℃; oxygen is still very effective to 40%. When the air excess coefficient down to 1.2 to 1.3 below the sudden decline in the combustion rate of coal. Burning is accelerated as the blower rotates. Drip zone, the mixture of slag and coal ash or unburnt char is not the control factor to increase the amount of coal injected. Studies on the influence of the position, angle and shape of the spray gun on the distribution of gas-solid phases show that these factors have a significant effect on the even distribution of coal particles in the combustion-supporting air flow, which is done by shock tube and schlieren of.