High alumina brick slag resistance of various refining furnace of great significance
Slag chemical corrosion of high alumina brick is some of slag composition and some ingredients at high temperature in the high alumina brick to chemical lining video, generate low melting (liquid), make the face melting of high alumina brick, loss to the slag. Slag infiltration of high alumina brick is high temperature liquid slag by porosity and crack pipe to infiltrate of high alumina brick, such as a variant of layer must be thick degree, then layer variant ellipsis, causing high alumina brick face destruction. And the function of the slag resistance of high alumina brick is refers to the high alumina bricks in the using process, when in contact with slag chemical corrosion of slag and infiltration ability to compete, it is one of the most key USES the function of high alumina brick.
Among various kinds of refining furnace, furnace slag infiltration was the cause of lining damage and chemical corrosion of one of the important reasons. So, to mobilize the function of the slag resistance of high alumina brick to mobilize refining furnace lining is important to the adoption of the furnace campaign. The function of the slag resistance of high alumina brick is important in its chemical synthesis, organizational structure and slag basicity and temperature, etc.
The important mineral MgO style high alumina brick and CaO show different slag resistance characteristics. MgO style contact with slag motional chemical industry because it is difficult, even happen necessarily degree of lining video, also don't generate low melting minerals. Such as MgO style to solid solution many FeO without liquid; MgO style to SiO2 in slag are also very, very strong ability to compete. So, MgO style of slag chemical corrosion resistance is strong. MgO style, however, poor resistance to slag infiltration capacity, high temperature furnace slag are easy to infiltrate MgO style (periclase), a variant layer.
Compared with MgO style, CaO and slag through sex is large, it is easy to be high FeO slag corrosion. So, CaO slag chemical corrosion resistance is poor. But it with slag of SiO2 lining video, generate high melting point or mineral C2S C3S, mobilize the slag viscosity, possessed the slag brick to penetrate inside. So, CaO resistance to slag infiltration ability stronger than the MgO style.
The higher the purity of high alumina brick, and slag because of the smaller, the less they generate low melting object, the stronger the ability to compete slag chemical corrosion.
High alumina brick structure more compact, slag brick to penetrate inside the greater the difficulty, the stronger the slag infiltration resistance ability.
Arouse the content of MgO style of high alumina brick, purity and density, can arouse the ability of high alumina brick slag corrosion resistance. Transfer the CaO content and density, can mobilize high alumina brick of slag infiltration resistance. In practical application, according to the operating premise of refining facilities, establish the most fitting for high alumina brick of MgO style/CaO, purity and density, high alumina brick for slag chemical corrosion and infiltration of all have good ability to compete, in order to get better use effect. Internship, rich in MgO style comprehensive slag resistance of magnesia dolomite brick function is better than that of dolomite brick. So, in the refining furnace slag line part of the most used through high heat sintering of high purity and high density magnesia dolomite brick.
Slag basicity (CaO + MgO style/SiO2) and temperature on the function of the slag resistance of high alumina brick has important influence. High alumina brick, for weak acidic slag compete ability are eroded by acid slag. But in high basicity slag has a strong ability to compete, but also in the range of the basicity must be followed slag basicity, high alumina brick for slag compete ability enhancement (slag corrosion ability of high alumina brick to reduce); The higher the temperature of slag, slag and the stronger the because of high alumina brick, chemical corrosion of high alumina brick, the more serious; The higher the temperature of slag, the lower the viscosity, the more easy to seep into the inside of the high alumina brick, constitute a variant layer. So, in the process of refining, after slag basicity and manipulation of slag temperature, which can effectively reduce slag corrosion and infiltration of high alumina brick, further arouse the using of high alumina brick furnace life. Such as taiyuan through of AOD furnace refining slagging process changes. Method (total alkaline slag) has developed a single slag refining process, in the brick who always keeps high basicity slag refining process, and effective control of the furnace temperature is too high and large amplitude, reduced slag corrosion and infiltration of high alumina brick and other discredit the utility of the situation, prolong the furnace lining the adoption of the furnace life. Specific operation is: before the AOD furnace into the molten steel, the first to furnace to join a group of lime and combining magnesium powder, mobilized early MgO style and CaO content in slag, the initial stage to achieve high basicity slag. In blowing process, following the rise of molten steel temperature, partial add lime, again make the furnace temperature and combining the highest temperature of effective control, reduce the slag of high alumina brick, high alumina brick lining of the AOD furnace furnace life unceasingly transfers.