Electric arc furnace oxygen, gas, toner, lime powder gun system
1 The main benefits of cluster jet oxygen gun application in electric furnaces are:
(1) It has various functions such as oxygen blowing, combustion and secondary combustion, and realizes centralized automatic control, thereby reducing the facility cost set up separately by each system and the process cost of separate operation.
(2) Due to the setting of the combustion function, the scrap can be preheated and melted in advance, thereby reducing the consumption of electric energy (at least 20kWh per ton of steel).
(3) Due to the strong impact and stirring capacity, the utilization rate of oxygen and sprayed charcoal powder is improved, thereby reducing the consumption of oxygen and charcoal powder.
(4) Due to the setting of the secondary combustion function, the furnace temperature is increased by making full use of CO combustion in the furnace, thereby reducing energy consumption. (5) Due to the reduction of splashing, the iron content in the slag is reduced, the metal yield is improved and the maintenance cost of the furnace body is reduced.
The cluster oxygen gun cuts and melts scrap more quickly, which can blow oxygen into the molten pool more efficiently, greatly improving the utilization rate of oxygen. First turn on the auxiliary oxygen system, delay the compressed air system for a certain time, and then turn on the fuel (or gas) system after a certain delay, and at the same time carry out the supply of main oxygen. When shutting down, the fuel and main oxygen should be turned off first, and then the compressed air and auxiliary oxygen should be turned off sequentially. Automatic alarm handling to prevent serious safety accidents caused by oil pressure exceeding compressed air pressure.
3. Composition of the tube furnace door gun device
The furnace door gun is composed of a furnace door water-cooled oxygen gun and a furnace door gun; The mechanical system is composed of boom rotation, gun body rotation, gun body swing and lifting system; The oxygen gun equipped on the furnace gun device can assist the melting during the melting period and decarburize and refine during the oxidation period. The furnace gun device is equipped with a carbon gun, which is mainly used to make foam slag.
4. Types of fuel for oxygen guns
The fuel used in the burner is solid, liquid and gas. Light diesel is currently preferred in liquid fuels, because it is convenient to use, clean, easy to maintain equipment, and is an optional auxiliary fuel. Gas fuel is mainly natural gas, and China currently has limited resources and uses less; Gas fuels such as gas are not used because of their low calorific value and large exhaust gas volume. China has developed solid fuel coal oxygen technology in combination with resource conditions, but the thermal efficiency of injection is low, the investment is large, and the preparation, storage, transportation and removal and separation of sulfur and ash residues in the combustion products of pulverized coal are more cumbersome.
5. Self-consumption tube furnace door carbon oxygen gun
At present, the electric furnace door gun basically adopts a water-cooled design. Due to the fact that water-cooled oxygen guns also have certain shortcomings, Badensteel has developed and applied self-consumable furnace door guns, which have the function of spraying lime and spraying carbon powder to create foam slag. Compared with the water-cooled oxygen gun, its advantages are large operating safety factor, large spray angle, and can directly cut scrap steel. The disadvantage is that the oxygen blowing tube has a high cost and cannot blow oxygen continuously.
6. EBT oxygen gun
Modern electric arc furnaces use eccentric bottom steel (EBT) technology to achieve slag-free steeling. This not only reduces the amount of slag in the steel production process, but also shortens the smelting cycle and reduces the temperature drop of the steel output. However, at the same time, it also makes the EBT zone one of the cold zones of UHP-EAF, resulting in a slower melting rate of scrap in this area, and the composition of the molten pool is quite different from that of the central area. In order to solve the problem of EBT cold area, EBT oxygen gun can be installed above the eccentric furnace side to blow oxygen and assist the melting in this area. The EBT oxygen gun can promote the melting of scrap steel in this area, and after the occurrence of the molten pool, increase the temperature of the molten pool in the EBT area, uniformize the composition of the molten pool, and realize the re-combustion of CO.