高炉滴落带初渣流动的实验研究

根据相似原理,对高炉滴落带初渣流动进行了区域模拟的实验研究。结果表明:在现代高炉操作条件下,初渣偏流现象是不可避免的;初渣在滴落带横截面上呈二次项分布。在正常操作条件下,铁液的滴落几乎不受横向气流的作用,因而,生铁一经生成便与初渣分离而垂直下滴,而初渣则主要集中在软熔带内边缘附近区域流动。初渣偏流影响到焦窗的透气性。提高焦炭强度,保证滴落带焦炭柱中大于20mm 的大顺粒组成高于80%,或对小颗粒焦炭进行分级整粒入炉,将减轻滴落带初渣偏流,改善高炉下部的透气性和透液性。

Experimental Investigation on the Early Slag Flow in Dropping Zone of a Blast Furnace

On the principle of similarity, the early slag flow in dropping zone is investigated hydraulically with an experimental set-up locally analogues to a blast furnace. The results indicate that a deviation of early slag flow from the vertical is inevitable in case of modern blast furnace operation, with a binomial distribution of early slag dropping on the cross-section of dropping zone. It is hardly ever observed that molten iron is dropping under the influence of horizontal gas flow when operating normally. Therefore, molten iron is separated out from early slags from the very beginning as it is forming then drops down vertically; while most of early slags are flowing in the vicinity of the lower side of softening zone.The deviation of early slag from the vertical has influence on the gas permeability of coke slits. To reduce such a deviation and further to improve the gas and liquid permeabilities of the lower part of blast furnace, the strength of coke should be raised insomuch that in dropping zone the grain size larger than 20 mm in a coke column will be over 80%, or to classify the fine-grain cokes when charging.