The role of taphole clay on the blast furnace
Blast furnaces use taphole clay when processing tapholes, usually water taphole clay, but when the steel output is high, this taphole mud is more susceptible to mechanical erosion and chemical erosion of slag iron, resulting in blast furnace slag iron Dirty tapping not only affects the smooth production of the blast furnace, but also prone to breakage of the taphole during the tapping process, leading to a large flow of taphole and causing accidents. At the same time, due to the swelling of iron mouth, accidents such as burns caused by the “rocket fire” on the iron mouth are prone to occur.
The main production ingredient ratio of anhydrous taphole clay is (%): brown steel jade 15-24%, silicon carbide 6-15%, coke 20%, white mud 12-16%, and tar 18-20%. The taphole clay has a compressive strength of 20Mpa, it is easy to open when the blast furnace opens, and it has good erosion resistance.
Low key components and large amount of medium temperature sintering agent will affect the stable iron tapping. The addition of sintering agent will make the shot mud produce low-melt at high temperature, so that the corrosion resistance of shot mud will be worse, and there will be splashing phenomenon during iron tapping. It is found that when the ratio is 2.5%, it saves 25 minutes of processing time compared with water cannon mud, and does not affect the iron ditch processing. When iron is tapped, the iron flow is stable.
Excessive addition of the key ingredient, white clay, will cause excessive shrinkage of the clay, resulting in cracks. If it is too small, it will affect the plasticity of the clay. On the basis of 12% of the addition of the clay, gradually increase the amount and find that the line changes after burning. +0.3%, good performance, high plasticity at the moment, good micro-expansion, no cracks during high-temperature tapping, effectively keeping away the iron channeling caused by no expansion and cracks, and the iron flow is not stranded and accompanied by splashing. In severe cases, there is a danger of burning the cooling stave.
Comparing the above anhydrous taphole clay with water taphole clay in the same period, the technical indicators of the blast furnace are as follows: the pass rate of tapholes increased by 2%, the punctuality rate of tapping increased by 6.6%, the pass rate of iron quantity difference increased by 8%, and the taphole tapping reduced wind The rate has dropped by 96%, iron tapping can be increased once a day, and the blast furnace operation coefficient has also increased.