The so-called oven drying is an operation that uses heating method to gradually adapt the furnace lining and electrode to charging smelting. Its main purpose is to dry the furnace lining and roast the electrode paste. The quality of oven drying will not only affect the service life of the furnace lining, but also directly affect whether the electric furnace can be put into operation smoothly. Therefore, the oven drying system table should be formulated in detail and strictly implemented in the opening plan.
There are three methods in the stage of oven drying: wood drying, oil drying and coke drying. This paper only introduces the coke drying. As the name implies, coke baking is a method of baking the furnace by using the combustion heat of coke. Large metallurgical coke with less ash shall be used to make fuel (particle size > 150mm). During the baking of electrode paste, it shall be ensured that the coke burns close to the electrode and is added in time. In order to help the combustion of coke, blowing and other methods can be used to assist the combustion. No matter which baking method is used, the purpose is to bake the electrode paste, so that the electrode has a certain ability to withstand current and prepare for the next electric baking. Therefore, the sintering state of the electrode and the height of the electrode paste should be frequently observed to timely judge whether the conditions for electric oven drying are available. In the previously formed process, the coke oven drying time is long (72-96 hours for 10000kva electric furnace). In production, it can be appropriately shortened according to the actual situation, so as to reduce the waste of coke.
The purpose of the electric oven is the same as that of the coke oven. Its main purpose is still to improve the furnace temperature and roast the electrodes so that the electric furnace can have the conditions for normal production. The electric quantity of the electric oven is determined according to the capacity of the electric oven and the brickwork material of the furnace lining. The low-voltage oven shall be used during the electric oven, so as to ensure the stability of the arc light as much as possible, and the load of the three-phase electrodes can be kept uniform by moving less electrodes. The power supply system of electric oven shall be strictly followed.
The electric oven determines the speed of the furnace temperature rise, the electrode sintering speed and the sintering quality. Therefore, the power supply system should be scientific according to the characteristics of the electrode sintering.