Study On The Metallurgy Performance Of High - Alkalized Casm Tn Vien Melting Reduction Slag

The Pingguo red mud is a iron-containing red mud of the Bayer process. Through the COREX smelting reduction the iron-making process handling Pingguo red mud. By reducing smelting recovery of iron; wet milling elution recovery of aluminum, sodium from the calcium aluminum slag which is obtained through reduction; rare metals were enriched in the leach residue for further recycling. This three metallurgical processes join together to achieve the comprehensive utilization of red mud very promising process route. Restore slag proposed higher requirements in the restore process. That the slag is not only to meet the requirements of the COREX process smelting in the metallurgical performance, but also the chemical composition of the slag meet the alumina late slag leaching industrial requirements. Therefore, under the conditions of that meet the leaching of alumina slag composition, how the metallurgical properties of the reduction slag, can meet the requirements of the requirements are the key scientific issues of the aspects to consider.The melting properties and the flow properties of the high alkalinity of the calcium aluminate slag (CASMTN) were determined in this paper. Discussed the impact of the law of the slag melting and flow properties which caused by the change of the alkalinity (CaO/SiOa), Al2O3, MgO, TiO2, Na2O in the composition. Observe the phase composition of the slag, and analysis the impact of the law between the phase composition and the metallurgical properties of the slag. The results are given as follows:(1) The hemisphere point temperature and flow temperature can be increased by increased the alkalinity of the slag; Al2O3and MgO content increases will make the hemisphere point temperature and the flow temperature of the slag decline; hemisphere point temperature and flow temperature leveling off after the first rapid decline with the increase of TiO2and Na20.(2) The temperature has greater impact of on the viscosity of the slag and the viscosity decreases as the temperature increases; the viscosity of the slag can be increased by increased the alkalinity; Al9O3and MgO content increases will cause the decrease of the viscosity of the slag; the right amount of TiO2and Na20help to reduce the viscosity of the slag and make the fluidity changed for the better.(3) The hemispherical point temperature, the flow temperature and the viscosity of the high alkalinity of the calcium aluminate slag is higher than the ordinary BF slag.(4) Study the internal structure and mineral of the calcium aluminate slag by X-ray diffraction (XRD) method combines the scanning electron microscope (SEM) of the energy spectrum analysis found that:In the high alkalinity of the slag, the high-melting substance such as dicalcium silicate (2CaO·SiO2), the free CaO and a small amount of perovskite (CaTiO3) is the main reasons which cause the high hemisphere point temperature, the high liquid temperature and the large viscosity. The slag with the high Al2O3content, Al2O3will reaction with CaO and Na2O to calcium aluminum melilite (2CaO·Al2O3·SiO2), the seven calcium aluminum twelve (12CaO·7Al2O3), and a small amount of nepheline (Na2O·Al2O3·2Si02), thereby decreasing the calcium aluminate slag melting temperature, while smaller the viscosity of the calcium aluminate slag. In the high MgO content of the slag, due to the presence of a large number of low melting point eutectic such as akermanite (Ca2MgSi2O7), monticellite (CaMgSiO4), magnesium Qiang pyroxene (Ca3MgSi2O8) which makes the high melting temperature of the slag reduce and the viscosity decreases. There will appear the compound calcium aluminum melilite (2CaO·SiO2·Al2O3) which have simple structure and lower melting point in the high content TiO2slag, so that the melting point and the viscosity of the slag are decreased. However, the presence of the perovskite, will result in an upward trend in the melting temperature and viscosity. The nepheline existence is the main reason to make the Na2O-containing slag the melting point is lowered and reduced the viscosity, Na2O·Al2O3generate a high melting point so that the melting point of the slag and the viscosity tends to increase.