Electric furnace enhanced smelting technology

The electric furnace is one of the indispensable smelting equipments for special steel production. At present, the competition in the industry is fierce, with about 45 minutes using a conventional converter to tap, if the use of electric furnace takes about 70 minutes, therefore, how to further shorten the arc furnace smelting time, reduce consumption, and thus significantly reduce costs, is the development of many special steel companies The inner needs. The commonly used technologies for enhanced electric furnace smelting are:


1. Electric hot iron hot metal with hot iron with a certain amount of physical heat, and contains high carbon, silicon, manganese and other high calorific value elements, after blowing oxygen oxidation can release a lot of chemical heat, so that the scrap quickly into red hot The state is very easy to cut with oxygen, so it can be achieved with the help of molten iron, to shorten the smelting time and improve the smelting efficiency.


Adding method: Furnace adopts stove top against hot metal, that is, the first time the material is added is about 50% of the total weight of the material, and then the electricity is passed through the well for about 8 minutes. The power is cut off and the lid is opened. The lifting equipment will contain molten iron. The iron ladle is transported to the top of the furnace, and the molten iron is poured into the furnace from the top of the furnace by aligning the electrode through the hole. The time is about 3 minutes, and then the furnace lid is energized and smelted.

2, RCB gun injection technology RCB gun has a strong decarburization ability, is to achieve the hot metal technology guarantee. RCB spray guns are generally installed on the wall of an electric arc furnace. The oxygen jet oxygen jet is sprayed into the molten pool at a supersonic speed and with a long bundle. It has a strong penetrating ability, a fierce metallurgical reaction occurs, the decarburization speed is quickened, and the molten pool can be well agitated. Conducive to molten steel temperature and chemical composition. In order to ensure the utilization of injected oxygen of RCB*, oxygen penetration ability and high decarburization speed, it is necessary to ensure sufficient pressure of oxygen, but excessive decarburization reaction will severely damage the lining refractory and water-cooled furnace walls. . General control pressure 1.2Mpa, decarburization speed 0.06-0.08% C/min.

3. Efficient foam slag technology The foam slag process is the best choice for high-impedance and ultra-high-power electric arc furnaces. Good foam slag can expand the interface of metallurgical reactions and facilitate the migration of reaction products; at the same time, it can realize good burial. Arc operation greatly improves the thermal efficiency of the arc.

The oxygen injected from the RCB* reacts with the carbon in the bath to produce a large amount of CO gas and to reach the conditions for the formation of foamy slag in a short period of time. With the oxidation of carbon in the molten pool, the carbon content in the molten pool gradually decreases. It is necessary to inject carbon powder into the furnace in time to keep the slag foamed. On the other hand, it can also reduce the iron oxide content in the slag and improve the metal. The rate of collection. As the reaction progresses, the alkalinity of the slag is reduced, and the foamed slag becomes unstable. At this time, it is necessary to add lime in batches at the appropriate time in the smelting process to increase the basicity of the slag.