Converter Repairing Brick

The furnace material was originally made of MS-88 sintered magnesia as the raw material, and the high temperature asphalt was used as the binder. Due to the low content of MgO in the main raw material, the structure of the furnace is loose, and the bulk density is small, and the porosity is high, so that the high-temperature steel scouring performance and the resistance to slag erosion of the furnace material are poor, and the use time is short, resulting in compensation. The number of furnaces is large, and the proportion of furnace time to the converter operation time is large, which seriously affects the effective operation rate of the converter. In addition, the use of a single high-temperature asphalt as a binder, because the high temperature asphalt softening temperature is not easy to carbonize, making the furnace charge sintering difficult, long furnace life, also affects the converter operating rate.

In summing up the experience of other refractory materials converters, and listening to the feedback from a steel mill on the use of the original furnace materials, combined with the actual operation of the magnesium brick section of the raw materials department, in the case of no investment in equipment, the raw material magnesium brick The production process of the section filling material has been technically improved in the following four aspects:

(1) The raw materials for production were changed from the original MS-88 to DMS-96. It is well known that the production of fused magnesia is subject to secondary melting and recrystallization. Compared with sintered magnesia, its grain size is coarse, its structure is dense, its bulk density is high, its porosity is low, and the content of impurities such as Ca0 and SiO2 is low. CaO/ SiO2 is high. Therefore, the converter material for the production of raw materials using fused magnesia has the characteristics of high-temperature resistant steel scouring performance and strong resistance to slag erosion, and its use time is significantly longer than that of the converter material which is produced by using sintered magnesia as raw material.

(2) The binder is changed from the original single high-temperature asphalt to medium-temperature asphalt and high-temperature asphalt mixed in a certain proportion. The converter material for the converter produced by using high-temperature asphalt as the binder has high residual carbon strength due to high carbon residue. However, due to the high softening temperature of the high-temperature asphalt, the furnace material used for the binder production is not easy to be carbonized. The furnace has a long sintering time. The converter material prepared by mixing high-temperature asphalt and medium-temperature asphalt in a certain proportion as a binder can not only maintain good high-temperature bonding strength, but also reduce the softening temperature of the bonding agent, and promote the rapid carbonization of the bonding agent, thereby shortening the compensation. The purpose of the furnace material sintering time.

(3) The gradation of raw material particles was adjusted according to the principle of tight packing. The ratio of raw material granules is 40 to 45% for coarse particles, 15 to 20% for medium particles, 10 to 15% for fine particles, 25 to 30% for fine powder, and 35 to 30% for coarse sand. 40%, medium particles are 20 to 25%, fine particles are 15 to 20%, fine powder is 20 to 25%, and the batch metering operation procedure is strictly enforced to ensure the accuracy of the particle ratio. The converter filling material prepared according to the compact accumulation principle level has high void filling rate and obvious bulk density, thereby effectively improving the erosion resistance and erosion resistance of the furnace material.

(4) The amount of the asphalt binder added is reduced. The hardening time of the asphalt binder is substantially inversely proportional to the amount of addition. Therefore, the amount of binder added is reduced as much as possible, and the amount of binder added is increased as the amount of binder added satisfies the residual carbon content of the furnace material. The longer the sintering time of the furnace material, the material of the furnace before and after the improvement of the production process