Preparation Of Microwave Heating Of Direct Reduced Iron Process

China as the world's first major steel-producing country, produced more than 80% of crude steel in the coke oven-blast furnace-converter process produced by the traditional long process in order to scrap its alternatives (direct reduced iron) as raw material, short-arc furnace process produced by electric arc furnace process steel less than 20% of China's crude steel output, while developed countries by the shortened process electric arc furnace production of electric steel accounted for about 50%. Conventional coke oven-blast furnace-converter steelmaking process is not only a long process of energy consumed in large quantities of pollutants discharged a large amount of the natural environment for human survival had a devastating impact, but also heavily dependent on scarce resources for coking coal, to its subsequent development has also brought a crisis! Meanwhile, with the steel-making process of the development of a short process, electric furnace steel is also growing. But the electric furnace with raw materials-steel scrap resources, has a serious shortage, particularly in high-quality scrap scarcity of resources, for the short process steelmaking process poses a severe challenge.Therefore, development of low-power, low pollution, environmentally friendly iron-making new technology for the electric steel-making process to provide more short-flow high-quality, low-cost raw materials, has become China's iron and steel industry strategy for sustainable development needs.As a new, pioneering cutting-edge technology of the direct reduced iron process, completely abandoned the coke oven-blast furnace converter production process model, eliminating the need for blast furnace ironmaking process of coking and sintering processes, effectively overcome the blast furnace smelting iron process long, high investment, high energy consumption, pollution, some disadvantages such as better adapted to the modern iron and steel enterprises to continue to achieve compact, efficient, continuous, virtuous clean and environmentally friendly direction of trends. And direct reduced iron with its low carbon content, total iron content was high, the high rate of metal-based, composition and stability advantages of low content of harmful impurities to become the preferred electric furnace steel scrap substitutes.This paper reviews the conventional direct reduction technology at home and abroad applied research the status quo, combined with the basic principles of microwave heating and characteristics, focusing on the direct reduction of microwave technology at home and abroad reviewed. Based on our present status of the direct reduction process proposed microwave preparation of sponge iron a new carbon-thermal reduction process.Experimental set to 40% and 60% of iron ore powder mixture composed of iron scale iron raw materials as raw materials, the system of microwave carbothermal reduction process Preparation of sponge iron, the optimum process parameters:Reduction temperature is 1100℃, Reduction time is 60min, Carbon content within is 22%.In this condition, can be metallized was 96.65% of the reduction product.The optimal process parameters were investigated under the desulfurization agent addition on reduction of rate of metal products, the results showed that:desulfurization agent addition in the range of 2 to 7%, could be ideal targets on the reduction of metal product.Experimental design using the core method-Response Surface Methodology preparation sponge microwave carbothermal reduction process was optimized. By Response Surface Methodology for the preparation of sponge iron microwave carbothermal reduction process of regression model: Yi=-1001.1594+1.6073X1+1.5857X2+11.6859X3-1.1679E-003X1X2-3.5379E-003X1X3-0.0343X2X3-6.3124E-004X12+7.6802 E-003X22-0.1528X32Where, X1 is the reduction temperature; X2 for the reduction time; X3 for the carbon content within; Y1 for the metallization rate of iron.High accuracy of the model to simulate the effect is remarkable, fitting well. Model analysis of variance showed that the reduction temperature, reduction time and reduction in carbon content of the metal-based products have a significant effect on the metallization rate.Obtained by Response Surface Methodology optimization of preparation of sponge iron microwave carbothermal reduction process optimization of process parameters:Reduction temperature is 1139℃, Reduction time is 28min, Carbon content within is 20.95%.In the optimization of process parameters can be metallized under the rate of 97.06% of the reduction product.Microwave through the initial separation of the carbon thermal reduction product beneficiation experimental study showed that when the magnetic current strength of 0.5A, you can receive full TFe of 86.68% iron content, metallic iron content of 83.78% of the direct reduced iron products, and direct reduced iron The recovery rate was 90.5%; when the desulfurization agent adding amount of 7%, the direct reduced iron sulfur content of only 0.06%, the direct reduced iron obtained in the sulfur content to meet the direct reduced iron levels Kun Steel Holding Standard 3 goods requirements; and direct reduced iron in the other impurities, such as C, P, SiO2 and water content, all reached the Kunming Iron and Steel Direct Reduced Iron Grade Standard 3 goods quality index requirements.