Nickel-making oxygen-enriching top-blowing immersion spray gun with longer service life

Abstract

The invention relates to a nickel-making oxygen-enriching top-blowing immersion spray gun with longer service life. The diameters of a cover cylinder, an air pipe and an oxygen pipe of the spray gun successively decrease gradually, and the cover cylinder, the air pipe and the oxygen pipe of the spray gun are arranged coaxially; a mixing chamber is arranged on the outlet end of the spray gun; a multi-stage swirler is arranged between the air pipe and the oxygen pipe of the spray gun; a single-stage swirler is arranged between the oxygen pipe and the fuel pipe of the spray gun; the single-stage swirler is a blade type swirler; and the multi-stage swirler is a six-stage blade type swirler. Due to the arrangement and improvement of the swirlers, the cooling degree is strengthened. Due to the arrangement of a fin, the bending degree of the spray gun is reduced effectively, oxygen and the air of the spray gun are mixed in advance, higher combustion efficiency is achieved, and the fuel is prevented from being adhered to the inner wall of the mixing chamber to burn down the inner wall of the mixing chamber. Because an air stop ring plate is arranged near a sleeve air outlet, the secondary combustion of carbon monoxide on the upper part of the furnace is realized, and the generation of elemental sulfur is inhibited effectively. The immersion depth of the spray gun can be controlled stably, the service life can be prolonged, and the change frequency can be reduced. In addition, the production operation rate can be reduced, and the production cost can be saved.

Description

technical field [0001] The invention relates to the technical field of metal smelting, in particular to a nickel-oxygen-enriched top-blown submerged spray gun with improved service life. Background technique [0002] The top-blown furnace process belongs to the oxygen-enriched top-blown submerged spray gun technology, and its technical essence lies in the use of a vertical spray gun immersed in the molten pool. The original design of the spray gun was designed and manufactured by Ausmelt Company, and there is no practical experience in the top blowing furnace nickel smelting process. Jinchuan Oxygen-enriched Top Blowing is the first nickel smelting using spray gun, creating a precedent of oxygen-enriched top blowing process for nickel smelting. [0003] The service life of the spray gun plays a key role in the continuous high-load production of the top blowing furnace, and the service life mainly depends on the structure, material and control level of the spray gun. The sp...

AI Technical Summary

Problems solved by technology

The spray gun designed by Ausmelt company has the following problems: (1) The structure of the spray gun swirl is unreasonable, resulting in insufficient cooling strength of the spray gun barrel, serious burning damage in the mixing chamber, and low life of the spray gun. just burn out

(2) The oxygen pipe of the spray gun is too long, so that the oxygen and the air of the spray gun are blown into the molten pool without being fully mixed, resulting in overoxidation of some materials in the molten pool, causing large fluctuations in the grade of low-nickel matte, and affecting the normal production of the top-blown furnace

(3) The length of the air mixing chamber of the spray gun is too short, resulting in insufficient mixing of oil and coal, incomplete combustion of fuel, and the precipitation of elemental sulfur

In addition, the fuel utilization rate is low, and the head of the spray gun is easily damaged. The damage mechanism is that the fuel is not completely burned in the mixing chamber, so that when the oil spray gun is used, the fuel burns on the wall of the mixing chamber, and the local overheating burns the mixing chamber of the spray gun from the inside out. When using a coal-fired spray gun, the coal sticks to the wall of the mixing chamber, which affects the effective cooling of the spray gun fluid to the spray gun, and local overheating burns through the spray gun mixing chamber from the outside to the inside

Moreover, part of the fuel does not enter the molten pool to participate in the reaction, and directly enters the boiler with the flue gas. In mild cases, the local temperature of the boiler is too high, resulting in a reduction in the life of the boiler tube in this part; in severe cases, the pulverized coal is deflagrated in the boiler, which may cause the boiler to explode

(4) The air duct of the spray gun sleeve is too short, resulting in insufficient oxygen content in the secondary combustion area, and some combustible substances (such as C, CO) and SO 2 Elemental sulfur is generated after the reaction, which has a great impact on the equipment in the subsequent process

(5) The furnace director can only judge the depth of the spray gun inserted into the molten pool by listening to the sound of the spray gun, observing the shaking of the spray gun and monitoring the back pressure of the spray gun and the oxygen of the spray gun, and then controlling the depth of the spray gun inserted into the molten pool by artificially raising or lowering the spray gun

(6) The material of the spray gun is 304 stainless steel with low heat resistance, the softening point is very low, and it is easy to be deformed and bent by heat, so that the spray gun cannot be inserted and lifted out of the furnace normally.

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