A process and a plant for preheating a metal charge fed in continuous to an electric melting furnace through a preheating tunnel provided with a horizontal conveyor, wherein the metal charge is hit, in countercurrent, by the exhaust fumes or gas leaving the electric melting furnace and by jets of gas ejected through a plurality of nozzles positioned on the hood of the tunnel. The nozzles are arranged in groups interspaced from each other in a longitudinal direction with respect to the tunnel, and generate a small-scale turbulence or inject small fast gas jets that can penetrate the main gas stream passing through the preheating tunnel, and simultaneously generate a “horseshoe vortex” structure composed of a descending central gas flow (“downwash”), and ascending flows (“upwash”) close to the side walls of the preheating tunnel, which enable a desired circulation of the gases.

A process and plant for preheating a metal charge fed in continuous to an electric melting furnace through a preheating tunnel provided with side walls, a vault and a horizontal conveyor, wherein the metal charge is enveloped in countercurrent by fumes or exhaust gases exiting from the electric melting furnace, includes causing an air intake from the surrounding environment through openings along the preheating tunnel to complete the combustion of the fumes or exhaust gases. The intake is regulated by acting on suction fans and/or on the openings, based on measurements by temperature sensors and/or the composition of the outgoing gases in or downstream of the terminal part of the tunnel. The metal charge is enveloped by jets of gas ejected through a plurality of nozzles arranged non-uniformly longitudinally on the vault of the tunnel, with a greater concentration on the top of the vault of the tunnel.

A device (1) for drying and/or preheating metallic and/or non-metallic materials, preferably scrap, comprises a receiving container (3) and a scrap basket (7) which is arranged in the receiving container (3) and has a gas-permeable bottom area (9). The receiving container (3) has at least one process gas inlet line (6) in its wall (4), via which a process gas with a temperature in the range from 200 to 1600° C. can be introduced into the receiving container (3), and at least an injector nozzle (19) arranged coaxially within the at least one process gas inlet line (6) via which a cooling gas can be introduced into the process gas.

A sealed feeder device utilized in an electric arc furnace (1), and a flue gas and temperature control method. The sealed feeder device comprises a sealed feeding chute (5) having an outlet sealedly communicating with a side wall of the electric arc furnace (1), and a material blocking sealed arc-shaped door (3) disposed in the sealed feeding chute (5). The material blocking sealed arc-shaped door (3) separates the sealed feeding chute (5) into a cold steel scrap storage chamber (18) and a material feeding and dedusting chamber (2), and is operated by a driving mechanism (34) to separate or connect the cold steel scrap storage chamber (18) and the material feeding and dedusting chamber (2). The method comprises: adopting the feeder device to divide the flue gas of the electric arc furnace (1) into two paths, and controlling, by a flue gas adjustment device (16), a ratio of a flue gas flow from a flow-splitting dust removal pipe (11) to that from a dust removal pipe (4) to obtain a required flue gas mixture temperature.

The present invention relates to a melting device comprising a loading shaft (13, 13a) and a tilting device (4) by means of which a furnace vessel (1) with a furnace vessel cover (10) can be tilted into different tilt positions around a tilt axis (5a), wherein the furnace vessel sealing region is formed as a convex, cylindrical mantel section shaped, surface, and the shaft sealing region of the loading shaft (13, 13a) is formed as a complementary concave, cylindrical mantel section shaped, sealing surface, such that sections of the sealing surfaces of the two sealing regions lie mutually opposite one another in the different tilt positions of the tilting device (4) such that the transition region between the loading shaft (13, 13a) and the furnace vessel (1) is at least substantially sealed in all tilt positions of the furnace vessel (1), and to a melting method, in which a bunker container (17, 17a) with charging material (39, 40, 41) is placed in front of the loading shaft (13, 13a) on the loading side, wherein over the further course of this method, the charging material (39, 40, 41) is preheated in the bunker container (17) by furnace gas, and after further transport of this charging material (39, 40, 41) from the bunker container (17, 17a) into the loading shaft (13), this charging material (39, 40, 41) is further preheated in the loading shaft (13) by furnace gas.

The present invention belongs to the technical field of metallurgy, and discloses a horizontal continuous feeding preheating device and an enhanced preheating method therefor. The scheme comprises that two dust removal ports are arranged at the front and rear parts of a horizontal continuous feeding preheating duct, and the horizontal continuous feeding preheating duct is divided into an enhanced preheating area and a flue gas preheating area by the two dust removal ports arranged at the front and rear parts of the horizontal continuous feeding preheating duct; burners are installed in the enhanced preheating area, and the two dust removal ports are connected with a flue gas adjusting distributor respectively by a flue gas pipeline the steel scrap preheating efficiency of the burners and electric arc furnace flue gas is increased by controlling the flow rate and temperature of mixed flue gas.

A burner comprises a central passageway and outlets for fuel and for stabilizing oxidant arranged peripherally around the central passageway, and comprises outlets within the burner through which biasing gas, such as gas comprising oxygen, can be injected to enable control of the direction of the flame that is generated by combustion of the fuel and the oxidant at the face of the burner.

Methods and systems for determining a feed rate (unit mass/unit time) of metallic scrap material in real time being charged to an electric arc furnace (EAF) is provided, in which the methods and systems determine the speed of the metallic scrap material in real time and the volume of the metallic scrap material in real time. The methods and systems also classify the metallic scrap material via a machine learning model based on digital images of the metallic scrap material and assign a density to the metallic scrap material. The feed rate is determined based on the speed and volume of the metallic scrap material and the assigned density.

A process and a plant for preheating a metal charge fed in continuous to an electric melting furnace through a preheating tunnel provided with a horizontal conveyor, wherein the metal charge is hit, in countercurrent, by the exhaust fumes or gas leaving the electric melting furnace and by jets of gas ejected through a plurality of nozzles positioned on the hood of the tunnel. The nozzles are arranged in groups interspaced from each other in a longitudinal direction with respect to the tunnel, and generate a small-scale turbulence or inject small fast gas jets that can penetrate the main gas stream passing through the preheating tunnel, and simultaneously generate a “horseshoe vortex” structure composed of a descending central gas flow (“downwash”), and ascending flows (“upwash”) close to the side walls of the preheating tunnel, which enable a desired circulation of the gases.

An apparatus for feeding and preheating a metal charge toward a melting furnace of a melting plant, comprising at least one conveyor channel for said metal charge, at least one hood disposed above said conveyor channel and scrap detection means able to identify the profile of the metal charge entering said conveyor channel. The present invention also concerns a plant for melting metal comprising said apparatus, and a method to feed and preheat a metal charge.