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At this stage, China is in a stage of rapid development in the process of industrialization, nation-building has been in demand for steel rigid state, at the same time, the iron and steel enterprises have increased the demand for iron ore. Although China has exploration Ming iron ore reserves has increased year by year, has been in the forefront of the world, but lean ore reserves in China account for about 98% of our total reserves, and there are poor ore is beyond mining - stay mine . Moreover, the international price of iron ore is also increasingly climbed almost impossible place, especially in the last two years, have cut, cut, making the iron and steel enterprises. The latest statistics from the China Steel Association: The average price of imported iron ore in the first nine months of this year rose 56.31 percent in 2010, after the failure of the Chinese iron ore price negotiations. The first nine months in China imported 357.6 million tons of iron ore, 11.53 million tons less than last year, although the decline in the number of imported iron ore in January-September, but imports of $ 55.689 billion of the total amount of 19.162 billion increase over the same period last year still U.S. dollars, equivalent to about 130.3 billion yuan. China's iron ore imports, but the loss of the right to speak, but the ultimate cause of the rigidity of the steel market demand is strong, and the weak iron ore resources to be controlled by others. Yunnan Huimin iron ore reserves, buried in shallow, easy to exploit, but due to the low grade ore, fine granularity, complex components, high levels of phosphorus, a very difficult election, for a long time there has been no development and utilization. Panxi area in China is rich in vanadium-titanium magnetite, and the composition and stability, low content of harmful elements such as S, P, low price, industrial storage up to 80 million tons. Yunnan Province is also distributed a rich resource of ilmenite, and concentrate better quality than the Panzhihua region, mineral placer mainly, easy to adopt easy election Ti02 high-grade silicon, aluminum, sulfur, phosphorus and other impurities content less , reported in the literature, there are more than 2000 tons of proven reserves. However, poor economic indicators for the southwest region containing ilmenite, blast furnace smelting difficult. , Cheap compound of titanium and Ti (C, N) generated in the process of smelting slag viscosity, poor mobility furnace conditions and slag separation of iron is not ideal, many problems still exist. Therefore, the use of a new smelting process development of existing large number of \In today's world, non-blast furnace ironmaking technology rapid development, the individual process has, by virtue of its unique advantages emerge. Currently, COREX smelting reduction technology in many countries around the world industrialized the HIsmelt smelting reduction technology has been widely promoted in the world, although its not yet industrialized, but its raw materials practical, energy saving and environmental protection, as well as the industrial feasibility has caused countries metallurgical industry attention. All experiments in this study are blowing molten reduction technology to deal with Yunnan Huimin high phosphorus iron, and Meng bridge ilmenite concentrate, explore the smelting temperature, alkalinity, with carbon than oxygen-rich top analog HIsmelt oxygen flow and holding time of smelting, and also experimental hybrid of high phosphate rock and ilmenite smelting, studied the behavior of phosphorus in the smelting process, titanium behavior. Experimental study of high phosphorus iron ore smelting, drawn: (1) temperature, alkalinity, with carbon than smelting have a double role. In order to maintain the slag has good liquidity, to achieve satisfactory recovery of iron, in order to maintain the high alkalinity, temperature and efficient dephosphorization slag, achieve better dephosphorization comprehensive experimental results and theoretical analysis, when the temperature is controlled at 1723K -1773K, alkalinity 1.3-1.5, with a carbon ratio of 0.9-1.0, and the flowing oxygen time was 10 minutes, the holding time is 30 minutes of the experimental conditions, can be obtained when the phosphorus content is less than 0.20%, a sulfur content of about 0.06%, The carbon content of less than 0.8% of the molten iron, iron recovery rate of about 85%. (2) Although this process the strong oxidizing atmosphere to cause the desulfurization effect is very poor, but the S low load of charge material into the furnace, in addition to relying on a higher basicity slag sulfur in the bath is stably fixed in the slag in the above ( 1) under the conditions of the desulfurization rate of up to 80 percent, and the high sulfur content of hot metal, does not require external furnace desulfurization. (3) emerge in the smelting process of soot, which contains phosphorus, sulfur compounds, so the drawn portion of phosphorus, sulfur may be out by gasification, i.e. relying gasification removing some of phosphorus, sulfur, it is feasible, in addition, part of the iron through the smoke to escape except to increase the iron loss, the need to control this. (4) analysis, the use of oxygen-enriched top-blown molten the Huimin high-phosphorus iron ore reduction technology smelting phosphorus content of 0.90% is feasible, In addition, try to use only phosphorus, low sulfur content coal as a smelting The reducing agent, directly reduce the phosphorus into the furnace, the sulfur load, thereby improving the quality of molten iron (5) of the silicon content in the resultant molten iron, the carbon content are low, and wherein the silicon content is often less than 0.1%. (6) smelting the Huimin high phosphorus iron ore slag system CaO-Al2O3-SiO2, No. 74-1607 substances Ca2 [Al (AlSi) O7] in all XRD pattern of existence, and the strongest diffraction peak. With the enhancement of the oxygen potential of slag of Fe valence elevated the final slag iron Fe304, form. (7) In one set of experiments of the oxygen flow, changing the experimental conditions and found that the high temperature feed is conducive to the removal of phosphorus. Through smelting ilmenite experimental study, drawn: (1) the use of oxygen-rich top blowing molten reduction technology smelting full high perovskite, iron recovery rate of 95%, the titanium content of less than 0.05%, and this entry technology can overcome the blast furnace smelting vanadium titanium magnetite high melting point solid solution of Ti (C, N) generate a large amount of foaming slag could easily lead to a charge clogging and flooding behavior problems. (2) the temperature, alkalinity smelting has a dual role. In order to keep the slag has good liquidity, to achieve the good smelting indicators, and in order to avoid the constraints of the short residue properties of high titanium slag and melting temperature, comprehensive experimental results, when T = 1550 ℃, C / O = 1.0, R = 1.2 optimum metallurgical condition, the output low-Ti, low Si, low P high quality hot metal. (3) high hot metal sulfur content of 0.3%, up to less than steelmaking requirements, it must be molten iron outside the furnace desulphurization. This is a defect of oxygen top-blown smelting reduction technologies can not be eliminated. Huimin ore is characterized as high phosphorus content, low sulfur content, Si02 content was high at the same time direct large amount of lead slag, smelting was higher phosphorus content in the hot metal. Meng Bridge concentrate the characteristics of high titanium content, sulfur content, SiO2 content slag less, but smelting hot metal sulfur content. Mixed high-phosphorus iron ore and ilmenite smelting experiments obtained: (1) With fitted into Huimin iron ore proportion of elevated iron recycling rises at first and then decreased. When fitted into Huimin iron ore ratio of 50%, the highest iron recovery of 95.1%; phosphorus content of pig iron is gradually increased from 0.0026% to 0.61%; pig iron in the sulfur content of the overall trend is to reduce the from 0.16% to 0.052%; another pig iron content of impurity elements basic to maintain a stable level, but the variation of the carbon content slightly larger, because the influencing factors of the experiment and contingency too. (2) From the perspective of dephosphorization and desulfurization analysis, as fitted into the Huimin Mine proportion increased, the distribution of the phosphorus ratio gradually decreased from 10.8 to 1, and the sulfur distribution ratio showed an increasing trend from 0.3 to 0.9. Their data seem to fully explain the disadvantage of the oxygen-enriched top-blown in the desulfurization of such technology, the advantages in dephosphorization. (3) Integrated data analysis, in Huimin Mine and Meng bridge concentrates ratio is 1:1, the data better. Iron recovery rate of 95.1%, the phosphorus content of pig iron and 0.36% sulfur content of 0.054%, and 0.031% titanium content.
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