CN1580292A

CN1580292A - Light composite steelmaking protective agent (slag)

Info

Publication number: CN1580292A
Application number: CNA031262805A
Authority: CN
Inventors: 杨久俊; 黄明; 毋雪梅; 董延玲; 黄沙
Original assignee: Zhengzhou University
Current assignee: Zhengzhou University
Priority date: 2003-08-04
Filing date: 2003-08-04
Publication date: 2005-02-16
Anticipated expiration: 2023-08-04
Also published as: CN1244704C

Abstract

This invention opens a kind of new type light compound steelmaking protective,which includes following factors: micropowder coal ash 35-50%,red mud 30-45%,carbon element remnant 10-20%, fluxing agent 5-15%, little regulator(calcium). The method of making is : mix micropowder coal ash, red mud levigated separately, carbon element remnant and fluxing agent according to calculate and match the compositions and contents as in the practice, being less than 1% of water. New type light compound steelmakeing protective made of dry micropowder coal ash which is less than 28 mum and red mud is excellent with simple process, little investment, wide material source, good effect, low cost. It can also make use of industrial waste a lot, in favor of protection of environment and dealing with staple solid waste, have good economic benefits and social benefits.

Description

Novel light composite steel-smelting protective material (slag)

Technical field:

The present invention relates to a kind of steel-making protective material, especially a kind of novel light composite steel-smelting protective material that is used for Iron And Steel Industry.

Background technology:

Smelting iron and steel all needs through the cast operation; and the main effect of steel-making protective material (slag) is the smooth cast of protection iron and steel solution; on it covers molten steel face on the molten steel ladle face or in the ingot mold; scum silica frost in the molten steel, deoxidation products, fire resisting material particle etc. can be absorbed rapidly, thereby eliminate the inclusion defect of cast steel ingot inside and outside.With superfined flyash, red mud is that main compound steel-making protective material (slag) floats on the molten steel face; along with flowing between steel ingot and the die wall, molten steel forms protective membrane (slag film); play insulation, lubrication and alleviate the chilling of ingot mould, play the thermosteresis that reduces the molten steel surface simultaneously and prevent the oxygenizement on molten steel surface scull.Relate in the ferrous metallurgy principle aspect steel-making protective material (slag) is with the surface properties general introduction of slag.Metallurgical reaction often relates to various phase interfacies, solidifies the character that needs to understand phase interface, and interfacial tension between the coexisting phase or surface tension are that the important physical amount of surface reaction or surface phenomenon is discussed.In the discharge that separates, is mingled with of metal and slag, when reaction,, the effect of absorption, slag and refractory materials of formation, phase interface and the assimilation of solid formation in slag or the like the problem of cenotype be there's no one who doesn't or isn't relevant with the interfacial tension or the surface tension of slag and molten metal.In smelting, molten metal and slag or separating of being mingled with and molten metal are very important to the effect of refractory materials, and this is and wetting between them and sprawl relevant.

At present, the main thing of the steel-making protective material (slag) that China's Iron And Steel Industry is commonly used has lime feldspar, melilith, cuspidite mutually, also has mullite, wollastonite, spinel and graphite etc.Suitably high CaO content and a certain amount of fluorine are all beneficial to steel-making protective material (slag) role effect.

Summary of the invention

The purpose of this invention is to provide a kind of the protection and form stable granular structure layer, sintered layer, class melting layer, melting layer in the use and have certain viscosity and good flowability and adsorptivity, can bring into play the novel light composite steel-smelting protective material (slag) of good action stablizing cast steel quality in steel-making.

Technical scheme of the present invention is:

The fusing assistant combination drying that the dried shape superfined flyash of＜28 μ m and red mud, carbon element anode scrap, the halogen compound of levigated＜28 μ m are respectively formed to moisture less than 1%, promptly get novel light composite steel-smelting protective material (slag).

Dried shape superfined flyash, red mud with＜28 μ m are main raw material; a kind of novel pouring in steel smelting steel protective material that composite part is fluxed and exothermic materials such as carbon element, graphite, tar are made, its velocity of diffusion, heat insulation effect, soaking time etc. are applicable to Pour Steel bag usefulness fully.

The aggregate that the dried shape superfined flyash of＜28 μ m is a kind of sieve and silica-sesquioxide of high degree of dispersion, calcium oxide and ferric oxide surpass 50% in the red mud, and be rich in potassium sodium nepheline, iron calcium aluminate Solid solution and calcium magnesium silicate, water lime stone, be the good raw material of metallurgic auxiliary materials, they have higher heat resistance and good thermal and insulating performance.The carbon element anode scrap is a netted high-carbon body behind the sintering of fine hard coal, Jiao, tar and graphite.Make full use of the performance of these materials, can compoundly be formed in granular structure layer, sintered layer, class melting layer, the melting layer that steel-making protection forms in using and have certain viscosity and good flowability, the novel light composite steel-smelting protective material (slag) of adsorptivity.Cost is than CaO, CaF ₂, graphite, the compounded protective material of refined carbon powder (slag) is low more than 30%.

Compared with prior art, the invention has the advantages that:

1, used flyash, red mud, the carbon element anode scrap of the present invention is waste, and material is easy to get, cheapness, has realized resource reutilization, uses it can enjoy country's reduction or remission of taxes treatment as raw material.

2, preparation technology of the present invention is simple, need not complicated processing unit and technological process.

3, production cost of the present invention is low, pollution-free, fully can suitability for industrialized production.

4, the present invention forms stable granular structure layer, sintered layer, class melting layer, melting layer and has certain viscosity and good flowability and adsorptivity in the steel-making protection is used, and can bring into play good effect to stablizing cast steel quality.

Utilize the dried shape superfined flyash of＜28 μ m, the novel steel-making protective material (slag) of the compound production of red mud in sum; have that technology is simple, less investment, wide, effective, the low cost and other advantages of raw material sources; can also utilize trade waste in a large number; help environment protection and large solid waste and handle, have good economic benefit and obvious social.

Embodiment:

1, dried shape coal ash sorting or levigate to＜28 μ m;

2, red mud (sintering process, bayer's process, integrated process all can) sorting or levigate to＜28 μ m;

3, the carbon element anode scrap is levigate to＜28 μ m;

4, solubility promoter is levigate to＜28 μ m;

With above material by required composition in the actual production and cubage proportioning, mixing, weather-proof dressing.

Embodiment:

With the dried shape superfined flyash (composition such as table 1) of Henan Feng Yuan Industrial Co., Ltd.＜28 μ m, China Changcheng Aluminium Industry Co's integrated process red mud (composition such as table 2), carbon element anode scrap (composition such as table 3), solubility promoter (composition such as table 4) is an example.

Table 1 Henan Feng Yuan Industrial Co., Ltd. superfined flyash chemical ingredients, specific surface area

	??SiO ₂	??Al ₂O ₃	??Fe ₂O ₃	??CaO	??MgO	??Na ₂O	??K ₂O	Loss on ignition	Specific surface area (cm ²/g)
	??SiO ₂	??Al ₂O ₃	??Fe ₂O ₃	??CaO	??MgO	??Na ₂O	??K ₂O	Loss on ignition	Specific surface area (cm ²/g)	Superfined flyash	??61.02	??31.20	??0.69	??2.30	??0.72	??0.68	??0.64	??1.03	??12000

Integrated process red mud chemical ingredients that table 2 China Changcheng Aluminium Industry Co is levigate, specific surface area

	??SiO ₂	??Al ₂O ₃	??Fe ₂O ₃	??CaO	??Na ₂O	??K ₂O	Specific surface area (cm ²/g)
	??SiO ₂	??Al ₂O ₃	??Fe ₂O ₃	??CaO	??Na ₂O	??K ₂O	Specific surface area (cm ²/g)	Levigate red mud	??22.87	??10.28	??11.50	??46.60	??2.20	??0.22	??＞9300

Table 3 carbon element anode scrap composition

	Volatile matter %	Ash content %	Sulphur content %	Voidage %
	Volatile matter %	Ash content %	Sulphur content %	Voidage %	The carbon element anode scrap	??＜1.0	????＜10.0	????＜1.0	????＞35

Table 4 fusing assistant composition

??CaF ₂	??SiO ₂	????S	????P	Sericite	Potassium felspar sand, yellowish-brown iron ore	Color and luster
??CaF ₂	??SiO ₂	????S	????P	Sericite	Potassium felspar sand, yellowish-brown iron ore	Color and luster	??＞90	??9.5	????0.10	????0.05	??＜5	Trace	Black purple

The superfined flyash 35～50% of＜28 μ m, red mud 30～45%, carbon element anode scrap 10～20%, the fusing assistant 5～15% that the halogen compound is formed, conditioning agent (calcium class) trace.

Novel light composite steel-smelting protective material (slag) good dispersity; the resistance toheat height; good heat insulating; moisture content is low; float on and form the granular structure layer on the molten steel; sintered layer; the class melting layer; the melting layer multilayered structure; can absorb scum silica frost rapidly; deoxidation; fire resisting material particle; Jiao of wherein containing; the netted high-carbon body of graphite has improved heat insulation effect and has guaranteed effective high temperature reduction reaction; flow expansion is good; to avoid surface of steel ingot to produce the crack and prolong steel ingot mold life play a part very important, to the crop rate that reduces steel ingot and to prevent that steel ingot from producing secondary pipe most important.Simultaneously because a large amount of foreign ions that exist in the protective material (slag); the principal crystalline phase of therefore separating out grows up to mostly and is elongated column or needle-like; and have and grow up to dendritic tendency; melt or residual glass are inserted in the gap of principal crystalline phase mutually; more increased the protection covering power of protective material (slag) on molten steel; be difficult for wandering and avoid the oxidation of steel, thereby make real steel-making is played a good protection of novel light composite steel-smelting protective material (slag).

Claims

1, a kind of novel light composite steel-smelting protective material (slag) is characterized in that: comprise the component of following weight unit, superfined flyash 35～50%, red mud 30～45%, carbon element anode scrap 10～20%, fusing assistant 5～15%, conditioning agent (calcium class) trace, its making method is; The red mud of superfined flyash and levigated respectively, carbon element anode scrap, fusing assistant by required composition in the actual production and cubage proportioning, combination drying to moisture less than 1%, promptly get novel light composite steel-smelting protective material (slag).

2, novel light composite steel-smelting protective material according to claim 1 (slag) is characterized in that: the particle diameter of the particle diameter of superfined flyash, the particle diameter of red mud, carbon element anode scrap, the particle diameter of fusing assistant be μ m all＜28.

3, novel light composite steel-smelting protective material according to claim 1 and 2 (slag) is characterized in that: fusing assistant is the halogen compound.

4, novel light composite steel-smelting protective material according to claim 1 (slag) is characterized in that: the specific surface area of superfined flyash is 12000cm ²/ g.

5, novel light composite steel-smelting protective material according to claim 1 (slag) is characterized in that: the specific surface area of red mud is＞9300cm ²/ g.

6, novel light composite steel-smelting protective material according to claim 1 (slag), it is characterized in that: the voidage of carbon element anode scrap is＞35%.