Patent classifications
F27B3/186
METHOD FOR MAKING STEEL IN AN ELECTRIC ARC FURNACE
The invention relates to the field of metallurgy, and specifically to a method for producing steel in an electric arc furnace. A known method for making steel in an electric arc furnace includes, at least, loading, into the working space of a furnace, a solid metal charge and, at least, solid carbon-containing materials, melting the charge using electric arcs, carburizing the metal using the solid carbon-containing materials during melting, and outputting metal and slag from the furnace. It is proposed to conduct the melting process with the addition, to the working space of the furnace, of a high-carbon carburizer in the form of a liquid phase of iron recovered from the arc combustion zone for the additional carburization of the metal, wherein the high-carbon carburizer is obtained from iron oxides and carbonaceous material. The iron oxides and carbonaceous material are fed into the arc combustion zone, the dimensions of which are limited by D=d.sub.p+6d.sub.el, where d.sub.p is the electrode pitch circle diameter and d.sub.el is the diameter of an electrode. The total carbon content, in free and dissolved forms in the liquid iron phase, does not exceed 30%. The total amount of carburizer used in melting does not exceed 20% of the mass of the metal charge. The carburizer is fed continuously or periodically into the working space of the furnace during the charge melting process. The feeding of carburizer begins as charge melting begins. The use of the invention results in increased liquid metal output by means of regulating carbon content in the course of melting, increasing the carburization level of metal from the very beginning of melting, and reducing the loss of iron to slag and smoke.
SYSTEMS AND METHODS TO PREHEAT FERROMAGNETIC SCRAP
An example embodiment of the present invention provides a system for preheating ferromagnetic scrap. The system can include a preheating unit that is configured to hold ferromagnetic scrap and to receive hot gases. The preheating unit may include a removable cover that can include an electrical magnet system. The electrical magnet system can comprise an electrical magnet, a lifting device configured to lower and raise the electrical magnet, a power system configured to provide electrical power to the electrical magnet, and an electrical control system configured to operate the magnet. A hot gases cleaning system may be fluidly connected to the preheating unit.
Preheating appartus for steel scrap and metallurgical melting vessel equipped therewith
A metallurgical melting vessel has a vertical shaft, surrounded by a housing wall, which receives steel scrap. At least one closure element, having laterally spaced-apart fingers extending parallel to one another, is mounted such that it can move between a closed position and an open position. In the closed position, the fingers protrude at least partially into the shaft for the purpose of holding back steel scrap. In the open position, the fingers free the shaft at least to such an extent that the steel scrap can fall from the shaft into the melting vessel. The at least one closure element is mounted so as to be movable from the side of the shaft into the shaft and laterally thereoutof.
Fixed-type electric furnace and molten steel production method
Provided are a fixed-type electric furnace enabling continuous operation which allows melting without the interruption of power supply and tapping in a fixed state, and a fixed-type electric furnace and a molten steel production method using same. The fixed-type electric furnace comprises: a preheating furnace which is disposed on the side of a melting furnace and preheats an iron source (scrap) using exhaust gas from the melting furnace; a supply means for supplying the iron source, which has been preheated in the preheating furnace, to the melting furnace; the melting furnace comprising electrodes for melting the preheated iron source; and a fixed-type discharge means for discharging molten steel which has been melted in the melting furnace, wherein the preheating furnace is integrally connected to the melting furnace.
Continuous feeding system to a smelting furnace of pre-heated metal material, in continuous, potentiated and combined form
A process for heating a metal feedstock (31) fed in continuous to a smelting furnace (30) through a second horizontal heating section (34) through which hot discharge fumes collected from said furnace (30) pass, said fumes exerting a heating phase of said feedstock (31), characterized in that, immediately before entering said second heating section (34), the feedstock (31) is subjected to a preheating phase by heating means other than the discharge fumes collected from the smelting furnace (30). In a plant for the embodiment of said process, said different heating means are envisaged inside a first preheating section (33), which is operatively connected with said second heating section (34) by means of an intermediate fume evacuation section (35), the fumes coming from said sections (33) and (34) being conveyed to said section. Said sections (33, 34) preferably have a tunnel configuration.
Apparatus and method to feed and preheat a metal charge to a melting furnace
An apparatus to feed and pre-heat a metal charge to a melting furnace of a steelworks comprises a feeding and pre-heating tower separate from the melting furnace provided with at least one compartment to temporarily contain said metal charge, transfer means to transfer said metal charge to said melting furnace and conveying means to convey the fumes exiting from the melting furnace to said compartment. The apparatus also comprises a post-combustion chamber, disposed adjacent to and below said compartment, and connected on one side to said compartment and on another side to said conveying means, the post-combustion chamber being configured to determine the expansion of the fumes introduced by the conveying means and to direct said expanded fumes toward said compartment along a path such as to determine a desired residence time of said fumes suitable to obtain at least the substantial complete combustion of the unburned gases present in said fumes.