Blow lance assembly for metal manufacturing and refining

Abstract

The present invention relates to a blow lance assembly for metal manufacturing and refining developed to control slag formation and oxidation, as well as the heat capacity of the reactor, and to maintain the operational conditions during loading and blowing. The assembly has in the lower part thereof two groups of gas outlets which determine two blowing conditions. The first group consists of oxygen flow nozzles having a converging-diverging form, and mostly ensures the reactions of oxidation and conveyance of the basic solid material, mainly calcium oxide, for initial slag formation and dephosphorisation in the end run refining phases. The second group consists of secondary injectors with various functions during each blowing stage, the first function at the beginning of the process being that of injecting oxygen as a post-combustion agent, the oxygen reacting with carbon monoxide generated by the main injectors, and the second function is that of accelerating the reaction with carbon in that the speed of the oxygen stream is increased, slag melting is accelerated in the initial stages and, finally, the oxidation of iron, one of the elements in the metal bath, is increased in order to reduce the phosphorus content during the final run refining phases.

Description

technical field [0001] The present invention relates to a blowing lance assembly for metal fabrication and refining, and more particularly to a blowing lance assembly for iron and steel fabrication and refining, developed to control slag formation and oxidation, reactor heat capacity and protection against charging and converting operating conditions. Background technique [0002] A BOF furnace (Basic Blown Oxygen Furnace) is a bottom-closed cylindrical vessel with a frusto-conical upper end with a large opening at the top for filling liquid pig iron and scrap, called the "mouth", and the "mouth". The small side opening of the pouring channel" through which the molten steel produced at the end of the primary refining is removed. [0003] In order to protect the metal shell of the furnace, a coating with a layer of refractory bricks is used to contain the molten pool at high temperatures of about 1700°C. [0004] The blowing process consists of performing a series of steps,...

AI Technical Summary

Problems solved by technology

[0017] Several problems can typically arise during the described operation: a) formation of solidified material (“skin”) around the blowing lance, resulting in increased diameter of the lance and scale and damage to the fume capture system; c) high logistics costs and processing costs to recover the metal content of the cured material in the spray gun; d) long time cleaning of the scale formed on the spray gun; e) caused by scale removal f) poor heat balance for large volumes of scrap; g) lack of control over slag formation times and high dissociation times of essentially solid materials; and h) lack of control over scrap melting and Dephosphorization Lack of Control

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