CN101871033A

CN101871033A - Method for making foamed slag by utilizing gas ash

Info

Publication number: CN101871033A
Application number: CN201010201126A
Authority: CN
Inventors: 李建军; 史永林; 叶文成; 樊猛辉
Original assignee: Shanxi Taigang Stainless Steel Co Ltd
Current assignee: Shanxi Taigang Stainless Steel Co Ltd
Priority date: 2010-06-11
Filing date: 2010-06-11
Publication date: 2010-10-27
Anticipated expiration: 2030-06-11
Also published as: CN101871033B

Abstract

The invention relates to a method for making foamed slag by utilizing gas ash. Firstly gas ash is added into a storing tank, carbon dust removal pressure ball is added to the bottom of electric furnace before smelting, then heavy burder scrap steel is added, finally light and thin materials are added, then power is switched on, after slag is formed, the valve at the lower part of the material tank is opened, inclined angles among three bundling guns are all 120 degrees, the inclined angle of each bundling gun and the horizontal plane is 10-25 degrees, nitrogen is utilized as current-carrying gas, and the bundling gun is utilized to blow the gas ash into electric furnace slag. The invention makes the best of the characteristic that gas ash has low specific gravity and is easy to transmit, the gas ash of iron works is directly blown into an electric arc furnace, carbon in the gas ash is utilized to react with ferric oxide, so as to generate CO gas, bubble with stable properties is formed in slag, so that the volume of slag is expanded, electric arc is wrapped, and electric efficiency is improved, and meanwhile corrosion to electric furnace refractory material is also reduced as the electric arc is wrapped by the slag.

Description

Utilize gas ash to make the method for foamy slag

Technical field:

The invention belongs to metallurgy industry environmental protection and energy saving field, be particularly suitable for making foamed slag use in electric furnace.

Background technology:

In arc furnace smelting procedure, in order to improve the utilising efficiency of electric energy, reduce the radiation of electric arc to furnace lining, often adopt submerged arc technology, in order to realize arc-covering slag operation, need making foamed slag usually.In order to make the foamy slag of stable operation, need in stove, to jet carbon dust, ferric oxide reaction in carbon and the slag generates CO gas, in slag, form the more stable bubble of character, play the effect of foaming, carbon dust about 5kg is sprayed approximately for making foamed slag needs in electric furnace ton steel in present many factories, and carbon dust price per ton is 700 yuan, and the appropriate litigation fees that is used to buy the winding-up carbon dust every year is high.

Summary of the invention:

In order to reduce cost, the gas ash of iron work directly sprayed in the electric arc furnace use as whipping agent to substitute carbon dust, can reduce the production cost of Electric furnace steel making factory, the invention provides a kind of method of utilizing gas ash to make foamy slag.

The equipment that the present invention selects for use is three boundling rifles, and concrete making method is: earlier with 2～2.5m ³Gas ash join in the storage tank, the preceding elder generation of smelting joins the electric furnace furnace bottom with 2～3 tons carbon dedusting ash pressure ball, add the heavy burder steel scrap then, the heavy burder steel scrap accounts for 50～70% of furnace charge gross weight, add frivolous material at last, frivolous material accounts for 30～50% of furnace charge gross weight, send then, after slag forms, with the valve open of batch can bottom, three mutual angles of boundling rifle are 120 degree, and every boundling rifle and horizontal plane angle are the 10-25 degree, utilize nitrogen as current-carrying gas, gas ash is blown in the electric furnace slag with the boundling rifle.Wherein, current-carrying gas pressure is greater than 0.4MPa, and the granularity of gas ash is less than 0.074mm, and the winding-up time is 30-40 minute.

The characteristics of the little easy conveying of the abundant sharp gas ash proportion of the present invention, directly spray into the gas ash of iron work in the electric arc furnace, utilize carbon in the gas ash and ferric oxide to react and generate CO gas, in slag, form the more stable bubble of character, cause the slag volumetric expansion, electric arc is encased, play the effect that improves electrical efficiency, simultaneously, because slag encases electric arc, also reduced erosion to the electric furnace refractory materials.

This method of using as whipping agent with the alternative carbon dust of gas ash has reduced the consumption of carbon dust, reduce the production cost of Electric furnace steel making factory, do not reduce simultaneously the performance of foamy slag, also digested the waste resource that produces in the iron manufacturing process, prevent environmental pollution, produced considerable economic and social benefit.

Embodiment:

Embodiment: the chemical ingredients of the gas ash that this is routine, composition such as following table:

The chemical component table of gas ash (wt%)

As can be seen from the above table, contain higher full carbon and full iron in the gas ash, and acidic oxide such as SiO ₂With neutral oxide impurity such as Al ₂O ₃Lower, P, S content are also lower, cause big negative impact can not for after the use point slag and steel, are the ideal materials of making foamed slag.

Before use, earlier gas ash being joined volume is 18m ³The taper batch can in.The nominal capacity of electric furnace is 50 villages, earlier the carbon dedusting ash pressure ball is joined furnace bottom before smelting, and adds the heavy burder steel scrap then, add frivolous material at last, send electricity then, after slag forms, as current-carrying gas gas ash is sent into coherent oxygen lance by transport pipe with nitrogen, spray in the electric furnace then.The transport pipe internal diameter of gas ash is 32mm, and totally three pipelines are arranged in parallel, and three mutual angles of coherent oxygen lance are 120 degree, and coherent oxygen lance and horizontal plane angle are 20 degree, and current-carrying gas pressure is 0.4MPa, gas flow 150m ³/ h jetted 32 minutes altogether, and the foamy slag that forms in the smelting process is stable, and noise is less.Whole process sprays into the about 2m of gas ash altogether ³, save 300 kilograms of carbon dusts.

Described heavy burder steel scrap is that the area that rolling process cuts away is not less than 600mm ²And thickness is more than or equal to the waste material of 80mm.

Described light material steel scrap is the waste material of the thickness that cuts away of rolling process less than 80mm.

Claims

1. utilize gas ash to make the method for foamy slag: the gas ash with 2～2.5m3 joins in the storage tank earlier, the preceding elder generation of smelting joins the electric furnace furnace bottom with 2～3 tons carbon dedusting ash pressure ball, add the heavy burder steel scrap then, the heavy burder steel scrap accounts for 50～70% of furnace charge gross weight, add frivolous material at last, frivolous material accounts for 30～50% of furnace charge gross weight, send then, after slag forms, with the valve open of batch can bottom, three mutual angles of boundling rifle are 120 degree, and every boundling rifle and horizontal plane angle are the 10-25 degree, utilize nitrogen as current-carrying gas, gas ash is blown in the electric furnace slag with the boundling rifle.

2. the method for utilizing gas ash to make foamy slag according to claim 1 is characterized in that described current-carrying gas pressure greater than 0.4MPa, and the granularity of gas ash is less than 0.074mm, and the winding-up time is 30-40 minute.