| With development of the iron and steel industry, rich ore resources are depleted, and the demand of iron ore has increased more and more, resulting in soaring the iron ore price. Steel companies are facing huge financial pressure. Sea sand iron ore is from the beach of New Zealand which is resource-rich and low cost, sources are more stable, but due to its high content of vanadium and titanium, coarse grain size, compact structure, hardness, high melting point and other reasons, it has not been largely used in steelmaking. This article aims to research producing carbon-containing pellets with sea sand iron ore by direct reduction to explore the characteristics of direct reduction of sea sand iron ore, to get the optimum parameters of sea sand iron ore in making the carbon-containing pellets and its direct reduction, and to put forward a program of comprehensive utilization of sea sand iron ore resource to provide the basis theory of largely use of such iron ore.For bad balling of sea sand iron ore, taking two measures of ball-milling pretreated and reasonable adhesive to improve the quality of pellets which made of sea sand iron ore. Drawn in the ball-milling pretreatment: the best ball-milling pretreatment time of sea sand iron ore is 60 minutes, ball-milling efficiency will decline if you increase the ball-milling time. In the experiment of palletizing, obtaining the optimal parameters for pelletizing, used composite binder (water glass binder and high-quality sodium bentonite binder), the reasonable ratio is 4.0% of water glass binder and 1.0% of high-quality sodium bentonite binder, sand grain size composition of raw materials (-300 mesh = 30%, 300 mesh ~ 200 mesh = 40%, +200 mesh = 30%). Under the condition, carbon-containing pellets meet performance requirements of the fixed bed and shaft furnace.In the direct reduction of carbon-containing pellets, the pellets of the best palletizing parameters was made for the raw material, single factor experiments and orthogonal design experiments were used to study the Influence of reduction temperature, carbon content, reducing time to direct pellets reduction without taking the impact of reducing atmosphere on the reduction into account, this is due to the reduction of carbon-containing pellets is the reduction of coal depend on reduction reaction itself, the reduction rate of carbon-containing pellets is mainly determined by the speed its own reduction reaction, it can suppress the impact of the external atmosphere. The experiment proves that the impact factors In proper order of direct reduction pellets: C/O molar ratio>reduction temperature> reduction time, and fix the optimal reduction of parameters that temperature is controlled at 1300℃, C / O molar ratio is 1.2, reduction time is 30min. Under these conditions, iron metallization rate in direct reduction reaches 94.01%. direct reduction iron of experimental production is analyzed by means of the scanning electron microscope and mineralogical analysis, the results show that: when the temperature reaches 1300℃, iron in pellets starts to aggregate, form a large area of iron joined crystal, and separate iron from gangue is easy, and significant separation of titanium-iron also occurs, below this temperature, the iron show a patchy distribution, even without forming a large area of iron joined crystal, titanium element is still large extent embedded in the iron, the majority of titanium in pellets have been reduced to TiC, TiN.Finally, a rational and integrated process plan based on experimental research in the laboratory was proposed:making carbon-containing pellets→direct reduction→Magnetic separation of iron powder and gangue which contain high vanadium and titanium.
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