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The continuous feeding EAF take the continuous preheating, continuous feeding and continuous melting as it’s technical characteristics. It adopts the manipulation of great remained quantity of steel, which made the cooker came into being molten pool at the begaining of melting. The cooker melted scrap steel by steel fluid. So it advanced heat transfer efficiency. At the same time, it made the foaming slag in whole course and the operation of covering arc become into a truth. It advanced the electric efficiency. The continuous is one of the competitive technology. It has been used sufficiently all over the world.This paper depicted the whole course of continuous feeding EAF route, analysed the theory of metallugy’s reaction. In a certain production parameters of the circumstances,I calculated the scrap preheating temperature, analysisde of the effect of preheating; The electric furnace of the energy balance model was established, calculated the thermal efficiency of electric furnace. Through field experiments, the slag bubble technology was sdudied Systematically. Through research some conclusions was followed:(1) The EAF at normal furnace smelting process is not expected to scrap the solid point arc, and the melting stage, At the beginning of Smelting, a start-pool was made, In continuous feedomg, preheating process, Arc heated pool, pool melted scrap at the same time. Therefore, the furnace lining of masonry, electricity, oxygen blowing to carbon, slagging dephosphorization,it has a lot of differences with ordinary electric furnace;(2) Preheating of Seal is the gas radiation mainly,it is proportional preheating temperature and scrap stayed in preheating channel, the longer the stay, the higher the preheating temperature; Preheating within the channel by changing the way heat, gas stove in the middle through the scrap, it can improve the effect of preheating;(3) Continuous feeding EAF remains steel around 40% in the furnace,improving the dynamic conditions,reducing the scrap melting time greatly and increasing productivity, The thermal efficiency of electric furnace is 74.7% in Jinan steel, higher than the ordinary electric furnace about 10 percentage points, according to the total energy equivalent to 652kwh/t,saving power 65kwh/t;(4) The main factors of electric furnace foaming slag has the physical nature (the slag viscosity and surface tension), the chemical composition of slag. The best conditions to create foaming slag as follows:R=2.2～3.0, FeO content 15%～20%, the temperature is 1570～1590℃, MgO content 6%～7%.Feeding rate was adjusted timely to make pool temperature and alkalinity stable.
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