KR20040001079A - a Method for Manufacturing Aluminate Clinker and Cement using a By-Product Steel and By-Plaster - Google Patents

Abstract

PURPOSE: A method for making calcium sulfoaluminate clinker and cement having high strength, fast setting property and expansion property by using waste by-products is provided to save natural sources and prevent environmental pollution. CONSTITUTION: The method for making calcium sulfoaluminate clinker comprises the steps of: mixing 30-70 wt% of dolomite sludge and 30-70 wt% of rolling end-sludge generated from steel industries, as CaO and Al2O3 sources, together with 4-20 wt% of a chemical gypsum by-product as a CaSO4 source; and firing the mixture at the temperature of 1000-1300 deg.C for 30 minutes or more. Further, the aluminous clinker is crushed and 1-50 wt% of gypsum is added to the crushed clinker to form cement.

Description

Method for Manufacturing Aluminate Clinker and Cement using a By-Product Steel and By-Plaster}

The present invention relates to a method for producing alumina clinker and cement using steel by-products and by-product gypsum, and more specifically, to the production of inorganic sludge and fertilizers discharged as by-products of the steel industry and by-products during flue gas desulfurization. Calcium sulfoaluminate clinker using gypsum (hereinafter "C ₄ A ₃ Clinker ") and steel by-products for the production of cement and a method for producing alumina clinker and cement using by-product gypsum.

Normally C ₄ A ₃ The clinker includes components such as CaO, Al ₂ O ₃ , SiO ₂ , SO ₃ , and the like, when an appropriate amount of anhydrous gypsum (CaSO ₄ ) and quicklime (CaO) is mixed with the manufactured clinker according to the mixing ratio thereof. Cement with expandable, fast-hardening and roughness is produced.

And C ₄ A ₃ belonging to Hauyne mineral Is the only mineral produced in the CaO-Al ₂ O ₃ -SO ₃ system, and since it is industrially produced from natural minerals containing SiO ₂ and Fe ₂ O ₃ as impurities, its calcined mineral is C ₄ A ₃ In addition, β-C ₂ S and C ₄ AF are contained.

C ₄ A ₃ with these characteristics Based cement, the needle and the main phase with the hydration reaction with the water eth- ring ZUID _{(C 3 A · 3CaSO 4 ·} 32H 2 O), mono-sulphate _{(C 3 A · CaSO 4 ·} 12H 2 O) and Ca (OH) _By showing the expandability by hydrate crystal growth, such as ₂ , it is possible to prevent the crack of the cured body due to dry shrinkage, which is a disadvantage of general Portland cement, and to improve tensile strength.

In addition, general Portland cement clinker is fired at a high temperature of about 1450 ℃, the main compound constituting the clinker has a composition mineral of C ₃ S, C ₂ S, C ₃ A, C ₄ AF, when hydration Calcium silicate hydrate (Calcium silicate hydrate: CSH), calcium hydroxide [Calcium dihydroxide: Ca (OH) ₂ ] will be produced.

In addition, the C ₄ A ₃ Clinker, since in the manufacturing 100~200 ℃ degree lower than a temperature for producing the 1,200~1,300 ℃ common Portland cement as well as the energy saving that is usually added when the mix Portland cement with ₃ C ₄ A According to the mixing ratio of CaO, CaSO ₄ , cement having high Al ₂ O ₃ component, roughness is high, SO ₃ component is high strength, and CaO component is expandable.

Therefore, the cement is mainly used to suppress the occurrence of cracks, roughness, high rigidity due to dry shrinkage which is a disadvantage of general Portland cement.

However, as described above, C ₄ A ₃ Clinker was generally manufactured mainly using natural bauxite, limestone, and natural gypsum.

The purpose of the present invention to improve this is to use a gypsum which is a by-product of the rolling terminal sludge and dolomite sludge and fertilizer manufacturing process by-product C ₄ A ₃ The present invention provides a method for producing alumina clinker and cement using steel by-products and by-product gypsum to produce clinker and cement.

In addition, by using these waste by-products, alumina clinker using steel by-products and by-product gypsum can be used to save the natural resources and reduce the environmental pollution caused by the landfill of these wastes. And to provide a method for producing cement.

Figure 1a, b, c is an X-ray diffraction diagram of the clinker produced by the present invention, respectively.

In order to achieve the above objectives, a by-product alumina clinker using steel by-products and by-product gypsum prepared by mixing in 30 to 70% by weight of dolomite sludge, 30 to 70% by weight of rolled terminal sludge and 4 to 20% by weight of Busan gypsum A manufacturing method is provided.

On the other hand, dolomite sludge is mixed in an amount of 30 to 70% by weight, 30 to 70% by weight of rolled terminal sludge and 4 to 20% by weight of Busan gypsum, and then calcined at a temperature of 1,000 to 1,300 ° C for 30 minutes or more to form an alumina clinker. There is provided a method for producing cement using steel by-products and by-product gypsum, which is pulverized to a brain specific surface area of 2,000 to 5,000 cm ² / g and added 1 to 50% by weight of gypsum.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the present invention, alumina C ₄ A ₃ , which is one of special cements, uses rolled terminal sludge as Al ₂ O ₃ source, dolomite sludge as CaO source, and phosphate gypsum as SO ₃ source. Prepare the clinker.

In addition, the C ₄ A ₃ Baekwoon Sludge and Rolled Terminal Sludge are used by-products generated in the steel industry, Busan Gypsum generated from fertilizer manufacturing process, flue gas desulfurization process, titanium oxide manufacturing process is used, and is produced by firing the above gypsum at 300 ℃ or more Anhydrous gypsum may be used.

In addition, alumina clinker is formed by mixing 30 to 70% by weight of dolomite sludge, 30 to 70% by weight of rolled terminal sludge and 4 to 20% by weight of Busan gypsum, and then calcining at a temperature of 1,000 to 1,300 ° C for 30 minutes or more. Is ground to a brain specific surface area of 2,000 to 5,000 cm ² / g, and then 1 to 50% by weight of gypsum is added to produce cement.

At this time, the gypsum is one or more selected from the group consisting of phosphate phosphate, titanium gypsum, desulfurized gypsum, natural gypsum and anhydrous gypsum.

And the chemical composition for each raw material is shown in Table 1.

TABLE 1

Here, the content of dolomite sludge used as a CaO source is 40.7% by weight, Al ₂ O ₃ of the rolled terminal sludge is 22.1% by weight, phosphate gypsum used as SO ₃ source is 44.2% by weight SO ₃ It contains a circle.

In addition, the blending range of the raw material is 52 to 48% by weight of dolomite sludge, 45 to 42% by weight of rolled terminal sludge, and 4 to 4% of phosphate gypsum phosphate The mixture is mixed to 11% by weight, and the mixture is calcined while maintaining at a firing temperature of 1,000 to 1,300 ° C. for at least 30 minutes in an calcination furnace, followed by air cooling.

At this time, the main mineral phase of the calcined clinker is C ₄ A ₃ , β-C ₂ S, C ₄ AF, MgO, and the like, and the clinker is mixed with anhydrous gypsum and slaked lime and pulverized to form a special cement exhibiting high strength, fast rigidity, and expandability.

The cement manufacturing process as described above consists of the main processes of drying, pulverizing, blending, mixing, firing, cooling, anhydrous gypsum and slaked lime, pulverizing mixing, packing, and transportation of raw materials.

Hereinafter, an Example is given and it demonstrates in detail.

EXAMPLE

Prepare the raw material by drying and grinding the milled dolomite sludge, dolomite sludge and phosphate phosphate gypsum having the chemical composition as shown in Table 1.

Subsequently, the prepared raw materials are sufficiently mixed by the formulation shown in Table 2.

TABLE 2

Then, the raw materials introduced in the compounding amounts as shown in Table 2 are mixed, dried, and then heated to 1,000 to 1,300 ° C. in a kiln, and then fired for 30 minutes or more, and when the firing is completed, they are cooled in air.

The chemical analysis values of the raw materials fired as above are shown in Table 3.

TABLE 3

That is, three chemical analysis values show almost similar chemical analysis values, but there is a slight difference in Al ₂ O ₃ content.

In addition, as a result of XRD analysis of the fired raw material, as shown in FIG. 1, Case 1 is shown in FIG. 1A, Case 2 is shown in FIG. 1B, and Case 3 is shown in FIG. 1C.

That is, the main mineral phase of clinker is C ₄ A ₃ , β-C ₂ S, and MgO, and all three compounds showed almost similar minerals.

As described above, according to the present invention, resources are recycled by manufacturing cement using petroleum phosphate produced as a by-product of rolling sludge, dolomite sludge, and fertilizer, which are inorganic sludges discharged as by-products in the steel industry. Using high value C ₄ A ₃ The clinker is manufactured, economical production is possible by minimizing the unit cost of raw materials, and there is an excellent effect of preventing environmental pollution due to landfill of waste by-products.

While the invention has been shown and described with respect to specific embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit or scope of the invention as provided by the following claims. I would like to clarify that those who have knowledge of this can easily know.

Claims (7)

C ₄ A ₃ To prepare alumina clinker containing, β-C ₂ S, C ₄ AF, MgO, dolomite sludge and rolled terminal sludge from CaO source and Al ₂ O ₃ source, and by using gypsum from Busan gypsum as CaSO ₄ source , Alumina clinker manufacturing method using steel by-products and by-product gypsum calcining the mixture at a temperature of 1,000 ~ 1,300 ℃ 30 minutes or more. According to claim 1, wherein the dolomite sludge is 30 to 70% by weight, rolled terminal sludge 30 to 70% by weight and by-product alumina using by-product gypsum and Busan gypsum, characterized in that the blended content Clinker manufacturing method. According to claim 1, The dolomite sludge and the rolling terminal sludge is a by-product generated in the steel industry is used, the Busan gypsum is characterized in that by using the by-products generated in the fertilizer manufacturing process, flue gas desulfurization process and titanium oxide manufacturing process Method for preparing alumina clinker using by-products and by-product gypsum. According to claim 3, The dolomite sludge and the rolling terminal sludge is used by-products generated in the steel industry, A method for producing alumina clinker using steel by-products and by-product gypsum, characterized in that the anhydrous gypsum produced by firing the by-product gypsum by-product produced in the fertilizer manufacturing process, flue gas desulfurization process and titanium oxide manufacturing process at 300 ℃ or more. The alumina using steel by-products and by-product gypsum according to claim 1 or 2, characterized in that the dolomite sludge, the rolled terminal sludge, and by-product gypsum are pulverized and mixed so as to have a particle size of 88 µm or less and a residual amount of 5 to 20% by weight. Method for producing vaginal clinker. Dolomite sludge is blended with 30 to 70% by weight, 30 to 70% by weight of rolled terminal sludge and 4 to 20% by weight of Busan gypsum, and then calcined to form alumina clinker formed by firing at a temperature of 1,000 to 1,300 ° C. for at least 30 minutes. A method for producing cement using steel by-products and by-product gypsum, which is pulverized to a specific surface area of 2,000 to 5,000 cm ² / g and added 1 to 50% by weight of gypsum. The method of claim 6, wherein the gypsum is mixed with at least one selected from the group consisting of phosphate phosphate, titanium gypsum, flue gas desulfurization gypsum, natural gypsum and anhydrous gypsum. .