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China is the largest country in the world steel output, which, China's steel output in 2008 was 501.16 million tons, accounting for 36.397 percent of the world's total steel output. The rapid development of the steel industry, its growing, China's iron ore resources are mainly dependent on imports, more than 60% of its dependence on foreign demand for iron ore. The total amount of imported iron ore in the world. Rising dependence on foreign iron ore resources has severely constrained the independent development of China's iron and steel industry in recent years, the soaring price of iron ore, has undermined the development of China's iron and steel industry. Looking for alternative resources of iron ore resources, is imperative. China is the world second copper producer countries, copper production was 3.71 million tons in 2008, incidentally, copper slag capacity of 8.16 million tons. This huge number of copper slag, containing about 326 million tons of iron, a huge number. Therefore, the combination of China's steel industry development trend, and copper slag with high iron content, a huge number of copper slag without losing additional resources as iron ore resources as ironmaking raw materials to ease the pressure of the development of China's iron and steel industry . Starting from the physical and chemical properties of copper slag, reduced iron from copper slag experiment to study the related factors. Slagging agent is not added to the copper slag CaO maintain the the molten pool alkalinity of 0.187, copper slag, (FeO) involved in the reduction reaction activity lower, according to the molecular theory hypothesis only 0.3405, and iron higher starting temperature of the reduction reaction of 1273K. With the increase in the mass of the slag forming agents CaO added to the same mass of copper slag, i.e. slag ternary alkalinity increases, copper slag (FeO) to participate in the reduction reaction activity gradually increased. When adding a certain amount to the copper slag slagging agents CaO ternary copper slag basicity becomes 1.2, the activity of (FeO) was increased to 0.5712, and greatly reduces the initial temperature of the iron reduction reaction, lowering as 653K. The coal reduced copper slag process, the alkalinity (1.2) and holding time (1500 ℃ insulation 120min) unchanged, C / Fe ratio of 1.33, the reduction rate of the copper slag of iron in substantially maximum to 93.82%, C / FE continues to increase , the reduction ratio of iron remain stable, and the increase in the C content in the resulting iron layer; constant of the C / Fe ratio (1.33), and incubation time (1500 ° C incubation 120min, the added amount of CaO increases i.e. puddle ternary alkalinity rise, the first increase in iron reduction is reduced, add to the copper slag slagging agent CaO alkalinity of the molten pool of 1,2, the reduction rate of iron is the maximum increase in the added amount of CaO, the reduction of the iron-rich S content in the set layer decreases gradually; copper slag basicity 0.187 1500 ° C holding time when t ≥ 40min, including the reduction of the basic completion of the iron, added to the copper slag slagging agent CaO molten pool alkalinity 1.2 completion of the reduction reaction of copper slag iron time As for the 1500 ℃ holding time t ≤ 10min, slag and iron complete separation time t ≤ 20min, added to the copper slag slagging agent CaO molten pool alkalinity of 1.55, the molten copper slag viscosity increases rapidly, the complete separation of slag and iron increased t ≥ 40min. Based on the above experimental results, the optimum parameters of the the solid reductant smelting reduction of copper slag iron: solid reducing agent and water quenched copper slag crushing particle size of 40 the slagging agent CaO mesh, add to the copper slag of the molten bath ternary alkalinity of 1.2, copper slag, add the amount of the solid reducing the C / Fe ratio, C / Fe ratio of 1.33, to the reaction system The pass into industrial N2 guarantee molten pool atmosphere is inert atmosphere, holding temperature of 1500 ° C insulation time of 20min.
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