| Pelletizing of electric Arc Furnace (EAF) dusts include zinc was the base of the technology of carbon-containing pellets direct reduction, so it studied the Particle size and the pelletizing-property of the EAF(electric arc furnace) dust. Experimental results show that the EAF dusts of Nan jing steel are so fine that all particles are less-than 5μm, which is very benefit to pelletize. The performance of pellets could reach experimental requirements without any binder. laboratory experiments studied the effects fallen strength and compression strength what C/O,time infects and so on.In order to studied feasibility of disposing electric Arc Furnace (EAF) dusts with carbon-containing pellets, it studied carbon-containing pellets direct reduction, and semi-industrial scale research was carried, proving feasibility of the equipment and heating-way that devised for the experiment. Research results show that the equipment and heating-way that devised for the experiment are working well. Besides, imposing the technology of carbon-containing pellets direct reduction to dispose EAF dusts had been studied, semi-industrial scale experiments were finished as well, and parameters has been optimized, the better parameters of roasting reduction method are shown as follows: excess coefficient of carbon 1.2, reduction temperature 1150℃, anticipate thickness 30mm, reduction time 60min,The treated pellets were semi-metallic pellet, total Ferrum content in the treated pellet was about 50%, the best got up to 54.7%; metallic ratio was about 60%-70%, the best got up to 88%; zinc oxide content in the collected zinc oxide powder exceeded 90%, while the percent of zinc content in the pellets is lower than 2%, which can meet the requirement of experiments, so the pellets can be used as the assistant materials of Blast Furnace, to some degree this realizes the recycle of metallurgical energy sources, it was proved that succeeded to recycle electric arc furnace(EAF) dust for carbon-containing pellets direct reducing technology. This is the first attempt to put the technique into practice in our country, at besides the author explored the parameters and heating-way of roasting reduction method, finally obtained the best parameters(reduction time,reduction temperature,carbon-oxygen ratio,heating-way,thickness of feed layer and so on). It will establish a hard basic for the industry production and application, of course, find a good means that were economy and efficiency and environmental to disposed EAF.In order to see about the influence of the charge container to the distribution of pellets temperature and of the hot furnace bottom to the material layer heat transfers, FLUENT6.1.2 has been used to calculate the temperature distribution of simulating quadrate and columnar container. Find out the point of the lowest temperature distribution of every container. It can be the foundation of raising the rate of material layer's temperature heightening and rising the efficiency of disposing EAF dusts containing Zn. The simulative result shows that, when the material layer is 30mm, 20min later after put into the stove, the heat supply hearth is becoming decalescence hearth.At the end, Pass to the contrast of the furnace type about merit and shortcoming, make sure that recycle of Electric Arc Furnace (EAF) dusts with rotary hearth, owing to the economic analysis of whole craft, show value of ZnO now, disposing Electric Arc Furnace (EAF) dusts with rotary hearth, integrated utilization about electric Arc furnace (EAF) dusts, it not only have good environment, but also high economical benefit.
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