Research On The Impact Of Harmful Elements In The Blast Furnace Of The Original Fuel

With the blast furnace producing operation, elements such as K, Na, Pb, Zn, As and S, et al, will go along with material and fuel into the system and bring adverse affects to the blast furnace smelting. Thus they were categorized as harmful elements. There are a lot of reports about the behavior and hazards of these harmful elements in the blast furnace, and their conclusions are relatively consistent and verified by production practice. The hazards can be elevated through reducing the entrance of harmful element and periodical removing.On the basis of previous studies, a further specific discussion about the effects of these harmful elements on the production operation and economic index of blast furnace is showed in this article and our aim is to provide operation guidelines and smelting system foundation for blast furnace proper and stable running under high harmful elements content load. According to the research on a domestic southwest ferrous industry NO.3blast furnace fuel composition and production status in2011and2012year, this article analyzes its everyday main operation parameter and technical economical index, and reveals their relationship with the load change of single harmful element by taking advantage of mathematical statistics method. This thesis also describes NO.3blast furnace production situation, and discusses the relationship between harmful elements load and furnace production operation and technical economical index and its guiding significance to actual production. Conclusions of the study as follows:(1)In the stable and anterograde blast furnace which the alkali metals load is less than9kg/t, the more alkalis load in the blast furnace, meaning the more burden ratio and the less coke rate and bad for improving oxygen enrichment percentage. When the alkali metals load in the blast furnace become higher, the blast furnace can’t receive high coal rate and reducing blast furnace slag basicity and furnace temperature is conducive to maintaining smooth operation of BF.(2)The higher lead load in the smooth operation of blast furnace, the physical heat and chemical heat of hot metal is also higher. The higher lead load result in the low burden ratio and high coke rate. When the lead load in the blast furnace is much than0.44kg/t, permeability index decreased with the increase of lead load. The blast furnace can’t receive high oxygen enrichment percentage when lead load is increasing. In a reasonable range, high slag basicity make smooth operation of blast furnace which much lead with in. Lead in the blast furnace can make the output cut.(3)In operation of BF is smooth and stable premise, the zinc load into BF has a linear relation with the permeability index, the higher zinc load, the higher permeability index. The zinc into the BF helps to improve the top pressure of the blast furnace. In a reasonable range, high slag basicity can make operation of blast furnace smooth and stable.(4)In normal production premise, the arsenic load into blast furnace has a linear relation with the permeability index, the higher arsenic load, the lower permeability index. The blast furnace can’t receive high oxygen enrichment percentage when arsenic load is increasing.(5)With the sulfur contented in raw material and fuel increase, in order to maintain the operation of blast furnace smooth and stable, and make the burden ratio become lower and lower, and make the coke rate become higher and higher. It have to raise slag basicity and hot metal temperature to a right range. The high sulfur load can reduce blast furnace production.