KR102134470B1 - Low carbon low burning cement clinker and preparing method thereof - Google Patents

Abstract

The present invention is a low-temperature calcined cement clinker comprising ilimit and calcium silicate, wherein the cement clinker is a low-grade limestone having a CaO content of 44 to 47% by weight, a fluidized bed boiler fly ash, bituminous coal flue gas desulfurization gypsum and alumina. A raw material composition containing a process sludge is pulverized to obtain a pulverized product, and a product obtained by firing the pulverized product at 1250 to 1350°C is proposed. The low-carbon, low-temperature firing type cement clinker of the present invention has a low firing temperature compared to the conventional ordinary Portland cement clinker, and thus has a small amount of carbon dioxide generated during manufacturing, and thus has an excellent greenhouse gas reduction effect. In addition, depending on the use, these cement clinkers may be pulverized to 2,500 to 4,500 cm2/g, or crushed products mixed with anhydrous gypsum and slaked lime may be used alone or as a mixture of 5 to 70% by weight in ordinary Portland cement. If it is, it can give functions such as expandability, fast-hardness, and high-strength to cement concrete.

Description

Low carbon low burning cement clinker and its manufacturing method{Low carbon low burning cement clinker and preparing method thereof}

The present invention relates to a low-carbon low-temperature firing cement clinker and a method for manufacturing the same, and more particularly, to a low-carbon low-temperature firing cement clinker capable of firing at a low temperature and reducing the amount of carbon dioxide produced during production, and a method for manufacturing the same. .

As the urbanization progresses, the architecture seeks to achieve ultra-high-rise, underground, and high-strength, and the existing cement concrete has been exposed to weaknesses such as cracks due to dry shrinkage, relatively slow strength, and strength per unit weight. In addition, many changes have been made to the construction method, such as construction attempting to utilize 3D printing technology, and thus the demand for concrete having new functions suitable for the new construction method is increasing.

Existing cement is generally manufactured using Portland cement clinker. Portland cement clinker consists of C ₃ S(3CaO.SiO ₂ ) and C2S(2CaO.SiO2), C3A(3CaO.Al ₂ O ₃ ), C ₄ AF(4CaO.Al ₂ O ₃ .Fe ₂ O ₃ ) In general, for the quality of Portland cement, it is required to contain a content of C ₃ S having a high production temperature of 50% by weight or more. In addition, Portland cement clinker must undergo a manufacturing process that is fired at a high temperature of 1,450℃ or higher. The cement industry is classified as a strategic energy reduction target at the national level because it requires a lot of energy due to the high-temperature calcination process. In addition, when mixing raw materials for the manufacture of Portland cement clinker, limestone, which accounts for 88 to 92% by weight of the raw material, is decarbonized, and the amount of CO ₂ emitted is 480kg to 510kg per ton of clinker. Clinker development is required.

An object of the present invention is to provide a cement clinker capable of reducing greenhouse gas emissions in the cement industry and calcinable at low temperatures by solving the above-described problems of the Portland Siemenk clinker.

In order to achieve the above object, in the present invention, it is a low-carbon, low-temperature plastic-type cement clinker containing irilimit and calcium silicate,

The cement clinker, as a source, crushing a raw material composition containing low-grade limestone having a CaO content of 44 to 47 wt%, fluidized bed boiler fly ash, bituminous coal flue gas desulfurization gypsum and alumina process sludge,

It provides a low-carbon low-temperature firing cement clinker, a product obtained by firing the pulverized product at 1250 to 1350°C.

Mixing a raw material composition containing low-grade limestone, a fluidized bed boiler fly ash, bituminous coal flue gas desulfurization gypsum, and alumina process sludge as a source to achieve another object of the present invention with a CaO content of 44 to 47 parts by weight; Pulverizing the mixture to obtain a pulverized product; Forming a molded body by molding the pulverized material; Drying and firing the molded body at 1250 to 1350°C; And quenching the calcined product. Including, a method of manufacturing a low-carbon, low-temperature plastic-type cement clinker for manufacturing the above-mentioned cement clinker is provided.

The cement clinker of the present invention has a low firing temperature compared to the conventional ordinary Portland cement clinker, and thus has a small amount of carbon dioxide generated during manufacturing, and thus has an excellent greenhouse gas reduction effect. In addition, these cement clinkers may be pulverized to 2,500 to 4,500 cm ² /g, depending on the application, or crushed products mixed with anhydrous gypsum and slaked lime may be mixed alone or in ordinary Portland cement with 5 to 70% by weight. When used, functions such as expandability, quick-hardness, and high strength can be imparted to cement concrete.

1 is a flow chart for explaining a low-carbon low-temperature plastic cement cleaner and a method of manufacturing cement using the same.
Figure 2 shows the thermogravimetric analysis (TGA) results for the CSA60 prepared in Example 1 of the present invention.
3A to 3D are X-ray diffraction (XRD) analysis results of a cement clinker using CSA40 of Example 1, CSA50 of Example 2, CSA60 of Example 3, and CSA60A of Example 4, respectively. It shows.
4A to 4C show XRD analysis results for the cement paste prepared according to Production Example 1.

Hereinafter, the low-carbon low-temperature sintering type cement clinker of the present invention, a method of manufacturing the same, and a cement manufactured using the same will be described in more detail.

It is a low-carbon, low-temperature plastic type cement clinker containing YiLimit and calcium silicate, and the cement clinker is a low-grade limestone having a CaO content of 44 to 47% by weight, a fluidized bed boiler fly ash, bituminous coal flue gas desulfurization gypsum, And a product obtained by pulverizing the raw material composition containing alumina process sludge and calcining the pulverized product at 1250 to 1350°C.

Portland cement clinkers generally require a lot of energy since they are fired at a high temperature of 1,450°C or higher. In the case of manufacturing Portland cement clinker, a cement clinker that can be fired at low temperature is required to save energy. In addition, it is urgent to develop a manufacturing method that reduces the amount of CO ₂ emitted while limestone, which accounts for most of the raw materials for the production of clinker, is decarbonized.

Accordingly, the present inventors can fire at a lower temperature than the Portland cement clinker to solve the above-mentioned problems, and the amount of limestone is reduced during the manufacture of the clinker, and thus, the illimit-containing cement clinker has significantly reduced the generation of carbon dioxide in the limestone. The present invention for the manufacturing method has been completed.

The two days limit is usually possible to manufacture Portland cement clinker of C ₃ S low temperature of 1250 to 1350 ℃ than the formation temperature of 100 to 200 ℃ it usually can be thermal energy saving over 30% compared to the Portland cement clinker have. In addition, 1,350 kg of limestone is used per ton of Portland cement clinker, whereas in the case of a clinker containing illimit, about 230 kg of limestone is used, the amount of CO ₂ generated by decarbonization of limestone can be drastically reduced, thereby reducing greenhouse gas in the cement industry. It is very effective as a reduction measure.

As shown in Reaction Scheme 1 below, the clinker containing irimitate (4CaO.3Al ₂ O ₃ .SO ₃ ) and calcium silicate C ₂ S as a main component reacts with water when there are anhydrous gypsum and slaked lime, and the bed or column etch Curing reaction proceeds by producing hydrates such as lysite (C ₃ A.3CaSO ₄ .32H ₂ O) and monosulfate (C ₃ A.CaSO ₄ .12H ₂ O).

[Scheme 1]

4CaO.3Al ₂ O ₃ .SO ₃ (Yeelimite)+ 8CaSO ₄ + 6CaO + 96H ₂ O ---> 3(3CaO.Al ₂ O ₃ .3CaSO ₄ .32H ₂ O) (Ethrinsite)

Depending on the amount and timing of the production of ethrinite, a hydrate of elimit, various functions such as rapid-hardness, expandability, high strength, etc. can be imparted to the cement cured body. The production amount and timing of these hydrates can be adjusted according to the reactivity of the irimit, the content, and the ratio of gypsum anhydride and slaked lime.

The amount of irimit in the cement clinker is 40 to 60 parts by weight, and the content of calcium silicate is 15 to 35 parts by weight. When the content of irilimit is within the above range, properties such as the strength of the cement obtained from the clinker are excellent, which is preferable. The cement clinker of the present invention may contain other impurities in addition to irimit, calcium silicate.

In the raw material composition, CaO content in low-grade limestone is 44 to 47% by weight. The content of low-grade limestone used in the present invention is 43 to 52 parts by weight as a CaO source, preferably 43.9 to 51.6 parts by weight. When the content of low-grade limestone is in the above range, the amount of carbon dioxide generated by decarbonation of limestone when manufacturing clinker is greatly reduced compared to the amount of carbon dioxide generated by decarbonation of limestone when manufacturing portland cement clinker.

Circulating fluidized bed combustion boiler fly ash discharged from the thermal power plant in the raw material composition contains free CaO and SO ₃ components, so it is recycled as a mixture of cement concrete or as a raw material of Portland cement. Unlike fly ash, which is generated in general thermal power plants, the development of recycling applications is required.

The circulating fluidized bed combustion boiler fly ash contains free CaO and SO ₃ components as described above, and thus is very limited in recycling. However, in the present invention, the above-mentioned free CaO and SO ₃ components are necessary components for the production of cement clinker, and thus are very suitable for recycling.

Such a fluidized bed boiler fly ash is a fly ash or a flooring material generated in a circulating fluidized bed boiler in which coal is burned. For example, the thermal power plant fluidized bed boiler fly ash has, for example, 20 to 30 parts by weight of SiO ₂ , preferably 25.62 parts by weight, Al ₂ The content of O ₃ is 10 to 20 parts by weight, preferably 11.21 parts by weight, the content of Fe ₂ O ₃ is 10 to 11 parts by weight, preferably 10.25 parts by weight, and the content of CaO is 20 to 30 parts by weight, preferably Is 24.50 parts by weight, the content of MgO is 4 to 5 parts by weight, preferably 4.80 parts by weight, the content of SO ₃ is 8 to 9 parts by weight, preferably 8.93 parts by weight, the content of Na ₂ O is 0.1 to 1.0 parts by weight Part, preferably 0.83 parts by weight, the content of K ₂ O is 0.1 to 1 parts by weight, preferably 0.65 parts by weight.

The thermal power plant fluidized bed boiler fly ash has the above-described chemical composition and is suitable for the production of illimite minerals.

The power plant fluidized bed boiler fly ash content is 18 parts by weight or less, preferably 10 to 18 parts by weight, more preferably 11.2 to 17.4 parts by weight.

The alumina process sludge has, for example, 2 to 3 parts by weight of SiO ₂ , preferably 2.99 parts by weight, 70 to 80 parts by weight of Al ₂ O ₃ , preferably 78.35 parts by weight, Fe ₂ O ₃ The content is 0.1 to 1 parts by weight, preferably 0.48 parts by weight, the content of CaO is 2 to 3 parts by weight, preferably 2.17 parts by weight, the content of MgO is 0.1 to 1 parts by weight, preferably 0.58 parts by weight, SO The content of ₃ is 0.1 to 0.8 parts by weight, preferably 0.42 parts by weight, the content of Na ₂ O is 5 to 6 parts by weight, preferably 5.65 parts by weight, the content of K ₂ O is 0.1 to 1 parts by weight, preferably Is 0.09 parts by weight. The alumina process sludge is a waste generated in the alumina manufacturing process and contains various components as described above, so it is very limited to recycle it. However, this alumina process sludge can be very usefully recycled as an Al ₂ O ₃ source in the production of cement cleaners containing irimite and calcium silicate of the present invention. Recycling the alumina process sludge in this way can reduce the waste disposal cost of the alumina process sludge, and recycle it to produce an illimit cement clinker, thereby reducing manufacturing cost.

The content of the alumina process sludge is 20 to 35 parts by weight, for example 21.2 to 35.9 parts by weight.

Flue gas desulfurization gypsum from thermal power plants uses bituminous coal, Petro-cokes or heavy oil as boiler fuel, and sulfur oxides (mainly sulfur dioxide) generated during combustion of thermal power plants using flue-gas desulfurization. It represents gypsum produced in the process of removal, and represents gypsum obtained by the reaction of calcium oxide and sulfur dioxide. This material has the same quality as gypsum mined in nature, and as a substitute for natural gypsum, it has a neutral pH and uniform quality with high purity compared to phosphate gypsum. The content of flue gas desulfurization gypsum in the thermal power plant in the present invention is 9 to 22 parts by weight, for example, 9.8 to 21.9 parts by weight.

It is preferable that the pulverized material has a pulverized material composition of 5 to 10% by weight of the sieved material having a sieve size of 90 µm. And the clinker is crushed to have a specific surface area (Blaine) of 2,500 to 5,000 cm ² /g, for example, 3,000 to 4,900 cm ² /g.

Referring to FIG. 1, a method of manufacturing a cement clinker of the present invention and a method of manufacturing cement using the same will be described.

The cement clinker of the present invention is prepared according to the following method.

First, a raw material composition containing low-grade limestone having a CaO content of 44 to 47 wt% as a source, a fluidized bed boiler fly ash or flooring, bituminous coal flue gas desulfurization gypsum, and alumina process sludge is mixed. The mixture is then ground. Grinding is performed with a ball mill. A pulverized product is molded to produce a molded body. The molded body is then dried and fired at 1250 to 1350°C.

Subsequently, the calcined resultant is quenched to prepare a cement clinker containing ilimit and calcium silicate. The rapid cooling is performed through a process of rapidly cooling in the air at 1250 to 1350°C, and may be cooled at a cooling rate of 500°C/min to 900°C/min. The rapid cooling as described above has an effect of increasing the hydration activity of the manufactured clinker.

The content of irimit in the cement clinker is 40 to 60 parts by weight, and the calcium silicate is 15 to 35 parts by weight.

The cement of the present invention can be prepared by mixing anhydrite and the like in the cement clinker. The anhydrous gypsum has an SO3 component of at least 50% by weight and a CaO component of at least 40% by weight. The use of anhydrous gypsum having such SO3 and CaO components is intended to prevent post-expansion due to other impurities and cause a stable hydration reaction.

The illimit (4CaO.3Al ₂ O ₃ .SO ₃ ) clinker prepared as above is shown in Scheme 1, unlike ordinary Portland cement, where C ₃ S and C ₂ S react with water to form calcium silicate hydrate while curing. As anhydrous gypsum and slaked lime are present, they react with water to form a bed or columnar ethrinite (C ₃ A.3CaSO ₄ .32H ₂ O) and monosulfate (C ₃ A.CaSO ₄ .12H ₂ O). A hydrate is produced and the curing reaction proceeds. In order to control the ethrinite production reaction according to the intended use, portland cement, anhydrous gypsum, slaked lime, etc. can be usually mixed during cement production. The cement thus obtained may be used alone or in admixture with ordinary falkland cement to produce cement concrete having expandable, fast-hardening and high-strength properties. The content of cement of the present invention in which the cement of the present invention is usually mixed with falkland cement is 5 to 70% by weight.

The mixing weight ratio of the cement clinker and anhydrous gypsum is 1:2 to 2:1. The mixing weight ratio of cement clinker and anhydrous gypsum is 1:2, 1:1 or 2:1.

The molar ratio of SO ₃ and Al ₂ O ₃ in cement is 0.5:1 to 2.0:1, for example 0.7 to 1.6:1. When the molar ratio of SO ₃ and Al ₂ O ₃ is in the above-described range, mechanical properties such as mortar compressive strength of cement are improved.

The sieve clinker is sieved with a sieve size of 75 µm, and the content of the residue on the sieve is controlled to an appropriate range. When the sieve scale size is 75 µm, the content of the residue on the sieve is controlled to be 2% by weight or less.

Hereinafter, the present invention will be described in more detail through examples. These examples are only for illustrating the present invention, it will be apparent to those skilled in the art that the scope of the present invention is not to be construed as limited by these examples.

Example 1: cement Clinker Produce

The low-grade limestone having a CaO content of 44 to 47% by weight as a raw material having the composition of Table 1, a fluidized bed boiler fly ash or flooring, bituminous coal flue gas desulfurization gypsum, and alumina process sludge were mixed to have the composition of Table 2 below to obtain a raw material composition.

division Content (parts by weight) moisture LOI SiO ₂ Al ₂ O ₃ Fe ₂ O ₃ CaO MgO SO ₃ Low-grade limestone 0.32 38.80 6.90 1.71 0.76 46.66 3.44 0.21 Fluidized bed boiler Fly ash 6.88 12.08 25.62 11.21 10.25 24.50 4.80 8.93 Flue Gas Desulfurization Gypsum 11.88 21.59 1.07 0.44 0.19 32.50 0.57 43.52 Alumina sludge 0.79 8.28 2.99 78.35 0.48 2.17 0.58 0.42

In Table 1, LOI stands for (ignition loss) as an abbreviation for lost of iginition.

The raw material composition was pulverized to perform sieving with a sieve size of 90 µm, so that the residual amount remaining in the sieve was 5-10% to obtain a pulverized product. The pulverized product was molded into spherical particles having a diameter of about 15 mm. With respect to 100 parts by weight of the ground, the water content is about 30 parts by weight.

After drying the molded product at 110° C., raise the temperature to 1,350° C. at a heating rate of 10° C./min in an electric furnace and bake it for 30 minutes, take it out at 1,350° C., and quench it in the air to low-carbon low-temperature carbon containing e-limit and calcium silicate. A molded cement clinker was prepared.

Example 2-4: cement Clinker Produce

A cement clinker was prepared in the same manner as in Example 1, except that the contents of low-grade limestone, fluidized bed boiler fly ash, bituminous coal flue gas desulfurization gypsum, and alumina process sludge were changed as shown in Table 2 below.

division Content (% by weight) Low-grade limestone Fluidized bed boiler
Fly ash Flue Gas Desulfurization Gypsum Aluminum sludge Sum Example 1
(CSA40) 51.6 17.4 9.8 21.2 100 Example 2 (CSA50) 50.0 11.2 12.5 26.3 100 Example 3 (CSA60) 46.1 - 18.0 35.9 100 Example 4 (CSA60A) 43.9 - 21.9 34.2 100

Production example 1: Preparation of cement

The cement clinker obtained according to Example 3 was sieved with a sieve size of 75 µm, the remaining portion of the sieve was 2% or less, and crushed to a specific surface area of 4900 cm ² /g, and the crushed product was crushed. Anhydrous gypsum was mixed with a composition as shown in Table 3 below to prepare cements having compositions 1 to 3.

Composition example Clinker grind Gypsum SO3/Al2O3 weight ratio Composition 1 2.0 1.0 1.1 Composition 2 1.0 1.0 1.8 Composition 3 1.0 2.0 3.3

Production example 2: Preparation of cement

The cement clinker obtained according to Example 3 was pulverized so that the residue on the sieve of size 75 µm was 2% or less and the specific surface area was 4900 cm ² /g. Cement was prepared by mixing with crushed cement clinker with slaked lime and natural anhydrite gypsum powder. The content of slaked lime was controlled to be 8 parts by weight with respect to 100 parts by weight of the total weight of the cement clinker, slaked lime, and natural anhydrite powder.

SO ₃ /Al ₂ O ₃ in the cement The mixing ratio was adjusted so that the molar ratio was 0.7 to 1.6.

Composition example SO ₃ /Al ₂ O ₃ molar ratio Composition 1 0.7 Composition 2 1.0 Composition 3 1.3 Composition 4 1.6

Production example 3-4: Preparation of cement

Cement was prepared in the same manner as in Production Example 2, except that the cement clinker prepared according to Example 1 and the cement clinker prepared according to Example 2 were used instead of the cement clinker obtained according to Example 3.

Comparative production example 1: Normal Portland cement

Usually, Falkland cement (specific surface area: about 3,390 cm ² /g) was used.

Evaluation example 1: Component analysis

If the chemical composition in each of the raw material composition for forming a cement clinker in Examples 1 to 4 are shown in Table 5 below.

division Loss of heat Content of each component (parts by weight) SiO ₂ Al ₂ O ₃ Fe ₂ O ₃ CaO MgO SO ₃ Na ₂ O K ₂ O CSA40 24.5 8.02 17.09 2.29 37.79 2.78 6.02 1.69 0.44 CSA50 24.3 6.62 20.14 1.59 32.29 2.56 6.30 1.98 0.43 CSA60 22.1 3.94 25.98 0.48 30.40 1.92 7.94 2.36 0.34 CSA60A 21.5 3.84 24.92 0.47 30.56 1.82 9.83 2.26 0.33

In Table 1, the loss on ignition is the amount of unburned residue in the incineration residue.

Evaluation example 2: Thermogravimetric analysis

Thermogravimetric analysis of the CSA60 prepared in Example 1 was performed, and the results are shown in FIG. 2. For thermogravimetric analysis, a thermogravimetric analysis (TGA, thermogravimetric analysis, TA Instruments, New castle, USA) was performed at a heating rate of 10° C./min in a nitrogen atmosphere.

As shown in FIG. 2, the endothermic peak appearing at about 120°C is due to the dehydration of crystalline water of the heat-desulfurized gypsum, and the endothermic peak and weight loss appearing at around 800°C is due to the decarbonation reaction of limestone. The reaction of Ilimit and C ₂ S can be confirmed by an exothermic reaction peak near 1,100° C., and it was confirmed that the reaction was almost completed up to 1,300° C.

Evaluation example 3: XRD analysis

In the cement clinker manufacturing method using CSA40 of Example 1, CSA50 of Example 2, CSA60 of Example 3, and CSA60A of Example 4, XRD analysis of the cement clinker according to the change of firing temperature was performed. XRD analysis was performed using an X-ray diffraction analyzer (X-Ray Diffraction, SIGMA PROBE, ThermoVG, U.K.), and the analysis results are shown in FIGS. 3A to 3D.

Referring to Figures 3a to 3d, CSA40 of Example 1, CSA50 of Example 2, CSA60 of Example 3, CSA60A4 of Example 4 to confirm the change generated according to the temperature rise and whether or not the generation of the illim is confirmed. In order to show the results of XRD pattern analysis for each temperature.

Elimit began to appear at temperatures below 1,100 °C and was found to be nearly complete at 1,300 °C.

In addition, 50 parts by weight of water was added to 100 parts by weight of the cement prepared according to Preparation Example 1 to prepare a cement paste. XRD analysis was performed on the cement paste. The analysis results are shown in FIGS. 4A to 4C.

As shown in Figures 4a to 4c, it was confirmed that irimitite and anhydrous gypsum react with water to produce ethrinite. On the third day of age, it was confirmed that irilimit was almost exhausted and became etrinsitite.

Evaluation example 4: cement Clinker Chemical composition analysis

The chemical composition of the cement clinker obtained according to Examples 1 to 4 was investigated, and the results are shown in Table 6 below.

Content (parts by weight) division SiO ₂ Al ₂ O ₃ Fe ₂ O ₃ CaO MgO SO ₃ Na ₂ O K ₂ O Example 1 (CSA40) 11.05 22.75 2.95 44.65 3.79 7.83 2.09 0.64 Example 2 (CSA50) 8.84 26.68 2.11 43.60 3.29 8.86 2.45 0.53 Example 3 (CSA60) 4.89 33.85 0.60 38.61 2.47 10.47 2.99 0.38 Example 4
(CSA60A) 4.87 31.98 0.58 38.84 2.24 12.76 2.85 0.40

Evaluation example 4: mortar compressive strength of cement

The mortar compressive strength of the cement prepared according to Production Example 2 and the cement obtained according to Comparative Production Example 1 was performed according to SL ISO 679 (Cement Strength Test Method). After preparing each mortar according to the above method, compressive strength according to 2 hours, 3 days, 7 days, and 28 days of age according to temperature (20°C) was evaluated. Thereafter, the results are shown in Table 7 below. For accurate experiments, all temperature conditions were compared and evaluated on the same day by storing materials and measuring containers 24 hours before the test day using a thermo-hygrostat. This test is the result of three or more comparative evaluations.

Table 7 below compares the mortar compressive strength with the cement of Preparation Example 2, and shows together the common Portland cement.

Production Example 2 SO ₃ /Al ₂ O ₃ molar ratio Compressive strength of mortar (Mpa) 2 hours 1 day 3 days 7 days 28 days 0.7 30.2 45.3 49.6 56.1 53.4 1.0 30.7 51.2 64.7 70.1 74.4 1.3 22.6 51.5 67.9 83.0 84.1 1.6 11.9 40.5 52.8 63.6 52.8 Comparative Production Example 1 Plain portland cement - - 24.0 37.2 51.5

As shown in Table 7, the cement of Production Example 2 was compared with the case of Comparative Production Example 1, and the mortar compressive strength of the cement produced using the illim limiter was earlier than that of the ordinary Portland cement in the comparative example, and the age was increased. 28 also shows a relatively high intensity value.

In addition, the mortar compressive strength of the cement prepared according to Production Example 3 and Production Example 4 was measured. As a result of the measurement, the cement prepared according to Production Example 3 and Production Example 4 exhibited a mortar compressive strength similar to that of Production Example 2.

The embodiments of the invention described above should not be construed as limiting the technical spirit of the invention. The protection scope of the present invention is limited only by the matters described in the claims, and a person having ordinary knowledge in the technical field of the present invention can improve and modify the technical spirit of the present invention in various forms. Accordingly, such improvements and modifications will fall within the protection scope of the present invention as long as it is apparent to those skilled in the art.

This study is the result of the research conducted by the Ministry of SMEs and Startups and the Korea Industrial Technology Agency as “Regional Industry Promotion Program (R&D P0005022)”.

Claims (8)

It is a low-carbon, low-temperature plastic cement clinker that includes illimit and calcium silicate.
The cement clinker,
As a source, the raw material composition containing low-grade limestone having a CaO content of 44 to 47% by weight, a fluidized bed boiler fly ash, bituminous coal flue gas desulfurization gypsum and alumina process sludge is crushed to obtain a pulverized material,
The pulverized product is molded to prepare a molded body, and the molded body is dried and fired at 1250 to 1350°C, the calcined product is quenched to mix illimit and calcium silicate, and the mixture is fired at 1250 to 1350°C. This is a product obtained by quenching at a cooling rate of 500°C/min to 900°C/min,
The content of the illimit is 40 to 60 parts by weight and the content of calcium silicate is 15 to 35 parts by weight,
The content of low-grade limestone in the raw material composition is 43 to 52 parts by weight, the content of the fluidized bed boiler fly ash is 10 to 18 parts by weight, the content of flue gas desulfurization gypsum is 9 to 22 parts by weight, and the content of alumina process sludge is 20 to 35 parts by weight,
The specific surface area (Blaine) of the cement clinker is 3,000 to 4,900 cm ² /g,
In the alumina process sludge, the content of SiO ₂ is 2 to 3 parts by weight, the content of Al ₂ O ₃ is 70 to 80 parts by weight, the content of Fe ₂ O ₃ is 0.1 to 1 parts by weight, and the content of CaO is 2 to 3 parts by weight Part, low carbon low temperature plastic molding with a content of MgO of 0.1 to 1 part by weight, a content of SO ₃ of 0.1 to 0.8 part by weight, a content of Na ₂ O of 5 to 6 part by weight, and a content of K ₂ O of 0.1 to 1 part by weight Cement clinker. delete delete delete According to claim 1,
In the thermal power plant fluidized bed boiler fly ash, the content of SiO ₂ is 20 to 30 parts by weight, the content of Al ₂ O ₃ is 10 to 20 parts by weight, the content of Fe ₂ O ₃ is 10 to 11 parts by weight, the content of CaO is 20 To 30 parts by weight, 4 to 5 parts by weight of MgO, 8 to 9 parts by weight of SO ₃ , 0.1 to 1.0 parts by weight of Na ₂ O, and 0.1 to 1 parts by weight of K ₂ O Low temperature plastic cement clinker. delete Mixing a raw material composition containing low-grade limestone having a CaO content of 44 to 47% by weight as a source, fluidized bed boiler fly ash, bituminous coal flue gas desulfurization gypsum, and alumina process sludge;
Pulverizing the mixture to obtain a pulverized product;
Forming a molded body by molding the pulverized material;
Drying and firing the molded body at 1250 to 1350°C; And
Including the step of quenching the calcined product at a cooling rate of 500 ℃ / min to 900 ℃ / min; including,
The size of the pulverized product is a low-carbon, low-temperature-fired cement clinker for manufacturing the low-carbon, low-temperature-fired cement clinker of claim 1 or 5, which is controlled so that the residual amount of the sieve having a sieve size of 90 µm is 5 to 10% by weight. Method of manufacturing.
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