KR20180027888A - Soft ground surface mixing and soil pavement process - Google Patents

Abstract

The present invention relates to a method for mixing an eco-friendly soft ground surface and paving soil without heavy metal elution. More specifically, the present invention relates to the method for mixing the eco-friendly soft ground surface and paving soil without heavy metal elution to promote hydration reaction and activity by using bottom ash discharged from the lower portion of a circulation fluidized bed boiler as irritant of granulated blast furnace slag fine powder to replace one kind of normal cement most widely used in a soft ground surface mixing process and a soil paving construction. The method for mixing a soft ground surface mixing and paving soil according to the present invention comprises: 1) a step of producing cement including granulated blast furnace slag fine powder and circulation fluidized bed boiler bottom ash; 2) a step of inputting 5 to 200 weight parts of the cement with respect to 100 weight parts of soil; 3) a step of uniformly mixing the soil with the cement; 4) a step of installing and tamping the mixture of soil and cement; and 5) a step of curing the mixture of soil and cement.

Description

{SOFT GROUND SURFACE MIXING AND SOIL PAVEMENT PROCESS}

The present invention relates to an environmentally friendly soft ground surface mixing process and a soil pavement process without heavy metal leaching, and more particularly, to a method for replacing one kind of ordinary cement which is most widely used in soft ground surface layer mixing and soil pavement, The present invention relates to an environmentally friendly soft ground surface mixing process and a soil pavement method which utilize the bottom ash discharged from the lower part as a stimulant for fine powder of blast furnace slag, and which does not cause heavy metal leaching to enhance hydration reaction and activity.

Generally, soil pavement method that can replace cement concrete or asphalt concrete is widely used in paving roads, parks, promenades, roads inside apartments. Most of these soil piles are made of cement as a binder and mixed with a small amount of soil such as yellow loam, marathon, etc., and sand, gravel, etc. with pigments such as iron oxide.

In connection with this, Korean Patent No. 1059188 entitled "Soil Pavement Method Using Environmentally Friendly Inorganic Oxide Soil Stabilizer" discloses a soil pavement method using a soil stabilizer, which is an environmentally friendly inorganic oxide, while directly using the soil of the site.

Specifically, the present invention discloses a soil pavement method capable of accelerating the hydration reaction of silicate, aluminate and carbonate present in a soil by catalytic activity of a soil stabilizer, thereby improving the compressive strength of the field soil. However, the soil stabilizer contains cement, and in the hydration reaction of the cement or carbonate, the heavy metal is eluted, so that the environmental pollution problem still occurs. In addition, the cement has a problem of being a main cause of environmental pollution due to the characteristics of the production process.

Korean Patent No. 0632705 entitled " Soil Solidifying Pavement Composition and Soil Solidifying Pavement Method Using the Same "discloses a method in which 100 mass% of mashato, 40 to 50 wt% of cement, 30 to 40 wt% of slag, 7 to 10 wt% of gypsum, 10-15 parts by weight of loess powder consisting of 4 to 8% by weight of fly ash and 3 to 7% by weight of fly ash, 1 to 6 parts by weight of ethylhydroxyethylcellulose, 1 to 5 parts by weight of red iron oxide and 12 to 15 parts by weight of water A solidified packaging composition is disclosed.

However, the composition disclosed in the above-mentioned technology has a problem that a soluble substance such as calcium hydroxide can be eluted in addition to an insoluble substance such as CSH exhibiting strength during hydration reaction, and heavy metals can be generated by cement. Further, since the ground pile having low binding force can not be used as it is at the time of construction, there has been a problem that a high-quality mamma or clay soil must be prepared separately.

Therefore, the main ingredient of limestone, clay, iron ore and the use of coal as a fuel is that words, serious product of natural resources and natural damage produced by thermal decomposition at a high temperature manufacturing process, a large amount of CO consumption of manufactured cement to exhaust the _second gas in It is essential to develop an environmentally friendly fire extinguishing agent that is environmentally friendly, has excellent durability, and has excellent reactivity with soil without leaching of alkali metal salts.

On the other hand, fly ash, which accounts for about 80% of the coal combustion by-products discharged from the pulverized combustion boiler of a thermal power plant, generates vitreous (amorphous) components when burned at a high temperature of about 1,350 ° C. The bottom ash, which is about 20% of the byproducts, is also used as cement and concrete raw materials. It also means coal ash that has fallen on the bottom of the boiler due to its own weight attached to the wall and the like during pulverized coal combustion. And is a porous material containing a large amount of vitreous. The pulverized coal boiler bottom ash has a particle size similar to that of fine aggregate and coarse aggregate for concrete, and is included in the structural lightweight aggregate of KS F 2534; it is estimated that it has enough lightweight and toughness to be used as structural lightweight aggregate And studies are being actively carried out to utilize these as aggregates. In recent years, studies have been actively carried out to induce geopolymer polymerization reaction by destroying the bottom ash glass film with a chemical such as sodium hydroxide after finely pulverizing the bottom ash of the pulverized coal boiler of the thermal power plant into ultrafine particles to physically activate it Is in progress.

In this connection, Korean Registered Patent No. 1339332 entitled " Binder containing Bottom Ashes "and Korean Patent No. 1410056 entitled" Cementless Concrete by Binder Including Bottom Ashes "and Korea Patent No. 1366293," Blast Furnace Slag and Bottom Ash The present invention relates to a concrete composition comprising a cement mortar composed of a cement mortar composed of a cement mortar and a cement mortar and a method of producing the cement mortar.

In Korean Patent No. 1312562 entitled " Binder composition for concrete containing bottom ash ", bottom ash is finely pulverized with a vibration mill at a rate of 6,000 to 8,000 cm ² / g to physically activate the particle surface, Respectively. All of these patents are intended to utilize a bottom ash of a pulverized coal-fired boiler of a thermal power plant.

Meanwhile, the coal combustion by-products discharged from the circulating fluidized bed boiler of the small and medium-sized cogeneration plant have low pozzolanic reactivity because the combustion temperature is as low as about 850 ° C and no vitreous is formed.

In the case of circulating fluidized-bed boiler fly ash, the content of CaO and SO ₃ was higher than that of fly ash discharged from pulverized coal boiler, and the recycled content was insufficient due to insufficient SiO ₂ content. However, as the KS L 5405 2015 fly ash standard was revised, And a recycling plan was prepared so that it can be mixed with some.

However, the bottom ash of the circulating fluidized bed boiler has a smaller particle size than that of the bottom ash of the pulverized coal boiler and is not porous. Therefore, it is difficult to utilize the bottom ash as a lightweight aggregate such as a pulverized coal boiler bottom ash. In addition, some recent research data on the bottom ash of pulverized coal bed boiler fly ash and thermal power plant pulverized coal boiler have been reported, but the data on the bottom ash of the circulating fluidized bed boiler has not been reported so far.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is an object of the present invention to provide a method of manufacturing a cement mortar, Friendly mixed soft ground surface layer mixing process and soil pavement method which does not cause heavy metal leaching which improves hydration reaction and activity by utilizing it as a stimulant of blast furnace slag fine powder.

In order to solve the above technical problems, the soft ground surface layer mixing process and the soil pavement process according to the present invention comprise: 1) a step of producing a solid fire containing fine granulated blast furnace slag and a bottom ash in a circulating fluidized bed boiler; 2) adding 5 to 200 parts by weight of the fireproofing material to 100 parts by weight of the soil material; 3) uniformly mixing the gravel and the fire; 4) installing and setting up a mixture of soil and solid fire; And 5) curing a mixture of the gypsum and solidified gypsum.

In addition, the step 1) may include 5 to 700 parts by weight of the circulating fluidized-bed boiler bottom ash with respect to 100 parts by weight of the blast furnace slag fine powder, and the circulating fluidized bed boiler bottom ash has a CaO content of 15 to 75 By weight and an SO ₃ content of 3 to 30% by weight.

In addition, it is preferable that the solidification step in step 1) further comprises 0.5 to 400 parts by weight of a circulating fluidized bed boiler fly ash having a CaO content of 10 to 55% by weight based on 100 parts by weight of the blast furnace slag fine powder.

Also, in the step 1), the solidifying agent may further comprise 0.5 to 400 parts by weight of a sulfate stimulant, based on 100 parts by weight of the blast furnace slag fine powder. The sulfate stimulant may be selected from the group consisting of natural anhydrous gypsum, petrocoke desulfurized gypsum, It is preferable to further include any one or a mixture of two or more of them.

In addition, in the step 1), the cement may further comprise 0.5 to 200 parts by weight of cement based on 100 parts by weight of the blast furnace slag fine powder, and the cement may be selected from the group consisting of a first type cement, a third type cement, a CSA (Calcium Sulfur Aluminate) Slag cement, fly ash cement, or a mixture of two or more thereof.

According to the present invention, it is possible to replace one kind of ordinary cement, which is most widely used in the surface layer mixing treatment of soft ground and soil pavement, with industrial by-products such as bottom ash and blast furnace slag fine powder.

Particularly, by using the bottom ash discharged from the lower portion of the circulating fluidized bed boiler as a stimulant of fine powder of blast furnace slag, hydration reaction and activity can be enhanced to provide an environmentally friendly soft ground surface mixing treatment and soil pavement method without heavy metal leaching.

Hereinafter, the eco-friendly soft ground surface mixing process and the soil pavement method without heavy metal leaching according to the present invention will be described in detail.

According to the present invention, the soft ground surface layer mixing process and the soil pavement process comprise the steps of: 1) manufacturing an environmentally friendly solid fire containing fine granulated blast furnace slag and bottom ash of a circulating fluidized bed boiler; 2) adding 5 to 200 parts by weight of the fireproofing material to 100 parts by weight of the soil material; 3) uniformly mixing the gravel and the fire; 4) installing and setting up a mixture of soil and solid fire; And 5) curing a mixture of the gypsum and the solidified gypsum.

First, the components and actions of the above-mentioned soft ground surface layer mixing treatment and soil-pavement method eco-friendly solid fire will be described in detail.

The boiler includes 5 to 700 parts by weight of a bottom ash of a circulating fluidized bed boiler having a CaO content of 15 to 75% by weight and an SO ₃ content of 3 to 30% by weight based on 100 parts by weight of the blast furnace slag fine powder.

The blast furnace slag is a by-product obtained by quenching slag in a high-temperature molten state generated as a by-product in a steelmaking blast furnace process with water. The blast furnace slag fine powder is called a latent hydraulic material because the amorphous coating is formed when it comes into contact with water and the hydration reaction does not occur by itself. The amorphous film must be destroyed in order for the latent hydraulic properties to be exhibited. The blast furnace slag fine powder can be used if it is a commercially available product having a specific surface area of 3,000 cm ² / g or more.

The circulating fluidized bed boiler bottom ash is generated in a circulating fluidized bed boiler using coal as the main fuel and in the lower part of the boiler in a manner of desulfurizing in the furnace together with limestone. In the desulfurization process of the circulating fluidized bed boiler, limestone is injected into the combustion chamber and burned together with the fuel, so that sulfur oxide and limestone in the combustion gas react in the furnace to remove sulfur in the combustion gas and produce anhydrous gypsum. It is carbonated and transferred to the quicklime component and discharged. Particularly, circulating fluidized-bed boiler bottom ash is burned at a temperature of about 850 ° C, and thus can not cause a pozzolanic reaction because there is no vitreous component. However, the CaO and CaSO ₄ components are higher than fly ash collected at the top, It can be said that it has a more excellent composition as a stimulant for fine powders. Therefore, it is a strong alkali substance having a pH of 11.5 or more and has a property of acting as a stimulant when used in the same manner as the blast furnace slag fine powder.

When water is added to a normal blast furnace slag fine powder, an amorphous film is formed on the surface, and the internal Ca ^{2 +} , Al ^3+, etc. are not eluted. However, when water is introduced after mixing the circulating fluidized bed boiler bottom ash, the CaO component contained in the bottom ash reacts with water to convert it into Ca (OH) ₂ , resulting in OH ^- and SO ₄ ^{2 - The} component destroys the amorphous film of blast furnace slag fine powder, facilitating the elution of Ca ^{2 +} , Al ^{3 +,} etc., and the elution ions generate CaO-SiO ₂ -H ₂ O-based hydrate, (3CaO.Al ₂ O ₃ .3CaSO ₄ .32H ₂ O) having an acicular structure, the surplus sulfur oxide densifies the structure in the hydrated body to improve the compressive strength of the hardened body . The bottom ash generally has a particle diameter of 5 mm or less, and its particle size is very large as compared with cement, slag, fly ash, etc., so that the state of the soil can be physically improved when mixed with the clay soil. In addition, it has the effect of stimulating the blast furnace slag itself in spite of its large particle size, so it can act as a stimulant and a fine aggregate and can be used directly as paste or mortar when mixed with water. However, in order to further enhance the stimulating effect of the blast furnace slag, it is preferable to classify and grind it to 1 mm or less.

The bottom ash preferably has a CaO content of 15 to 70% by weight. If it is less than 15% by weight, the content of CaO existing in the form of pure CaO itself is insufficient, except for about 10% by weight of CaO present in the form of CaCO ₃ and CaSO ₄ . That is, since the pure CaO reacts with water and is converted into Ca (OH) ₂ and the amount of OH ^- ion generated is insufficient, the amorphous film of the blast furnace slag fine powder is difficult to break down in a short period of time. The pure CaO present in the bottom ash reacts with water and absorbs, exotherms and expands to form Ca (OH) _2. The reaction equation is as follows. The volume expands about 1.99 times.

CaO + H ₂ O-> Ca (OH) ₂ + 15.6 kcal mol ^-1

Therefore, the pure CaO component reacts with water to convert it into calcium hydroxide, and it also acts as an alkali stimulant of fine powdered slag powder. However, due to the increase in temperature due to heat generation, the hydration reaction of the blasted slag powder is promoted and the effect of compensating the volumetric shrinkage Role and so on. On the other hand, if the CaO content is more than 70% by weight, the CaO content existing in the pure CaO form is excessively absorbed, excessively absorbing the water, and excessive heat generation and expansion may occur and cause cracks. Therefore, it is necessary to perform the chemical quantitative analysis before the raw material in the bottom ash, and the CaO content should be 15 to 70% by weight.

The bottom ash preferably has an SO ₃ content of 3 to 30% by weight. If it is less than 3% by weight, the content of SO ₃ capable of stimulating slag is insufficient, so that the strength is difficult to manifest. If it exceeds 30%, the content of SO _{3 which} does not react with the excess amount of slag is present. It is preferred to analyze the chemical composition to use the bottom ash within the above range.

The amount of the bottom ash is preferably 5 to 700 parts by weight based on 100 parts by weight of the blast furnace slag fine powder. When the blending amount is less than 5 parts by weight, the effect is not exhibited. When the blending amount is more than 700 parts by weight, The strength is greatly lowered.

In addition, the boiler further includes 0.5 to 400 parts by weight of circulating fluidized-bed boiler fly ash relative to 100 parts by weight of fine blast furnace slag fine powder. Preferably, the circulating fluidized bed boiler fly ash is discharged from a circulating fluidized bed boiler dust collector having a CaO content of 10 to 55 wt%. The circulating fluidized bed boiler fly ash may be any one or a mixture of coal, paper sludge, solid fuel, and biomass.

The circulating fluidized bed fly ash serves both as a stimulant of blast furnace slag and as a water-absorbing agent in the soil to rapidly solidify the soil particles to physically improve and to prevent shrinkage.

The circulating fluidized bed boiler fly ash is preferably mixed in an amount of 0.5 to 400 parts by weight with respect to 100 parts by weight of the blast furnace slag fine powder. When the blending amount is less than 0.5 parts by weight, the effect is not exhibited. When the blending amount is more than 400 parts by weight, The relative amount of water is relatively reduced, and the potential hydraulic property is lowered, and the fluidity may be lowered due to a relatively large amount of water absorption.

Also, in order to increase the strength, 0.5 to 400 parts by weight of a sulfate stimulant is added to 100 parts by weight of the blast furnace slag fine powder, and any one or a mixture of two or more of natural anhydrite, petroleum coke, . It is preferable that the sulfite stimulant is mixed with 0.5 to 400 parts by weight of 100 parts by weight of the blast furnace slag fine powder. If the amount is less than 0.5 part by weight, the effect is not exhibited. If the amount is more than 400 parts by weight, It is present, and it severely lowers the strength.

The cement may further comprise 0.5 to 200 parts by weight of cement based on 100 parts by weight of the blast furnace slag fine powder to improve the initial strength. The cement may be selected from the group consisting of a first type cement, a third type cement, an agate type cement, a CSA (Calcium Sulfur Aluminate) , Blast furnace slag cement, fly ash cement, or a mixture of two or more thereof. It is preferable that the cement is mixed with 0.5 to 200 parts by weight with respect to 100 parts by weight of the blast furnace slag fine powder. When the blending amount is less than 0.5 parts by weight, the effect is not exhibited. When the blending amount exceeds 200 parts by weight, Hazardous substances can be eluted and economic efficiency is also insufficient.

Hereinafter, the soft ground surface layer mixing process and the soil pavement method according to the present invention will be described.

In the step 2), 5 to 200 parts by weight of the fireproofing material is applied to 100 parts by weight of the gypsum, and the amount of the soil, the fine aggregate and the coarse aggregate May be mixed and used. In addition, it is possible to control the charging ratio of the fire according to the state of the soil, preferably 5 to 200 parts by weight based on 100 parts by weight of the soil. When a fire is added in an amount of less than 5 parts by weight, it is difficult to exhibit a predetermined strength. When the fire is added in an amount exceeding 200 parts by weight, the strength is greatly increased, but scattering dust is excessively generated.

In the step 3), it is preferable to mix the soil and the fire with each other according to the water content of the soil so that the dry mixing method or the water may be additionally added so that the wet mixing can be mechanically well mixed .

In the step 4), when a mixture of soil and solidified fire is installed and compaction is performed, additional moisture may be supplied so that the hydration reaction is fully manifested.

In the step 5), it is preferable to cure the mixture of the soil and the fire with no external shock until the curing is sufficiently carried out, and it is preferable that the person or the equipment enters the room after curing at room temperature or curing at a sufficient temperature.

Hereinafter, preferred embodiments and comparative examples of the present invention will be described. The following examples are intended to illustrate the invention and should not be construed as limiting the scope of the invention.

Comparative Example

30 parts by weight of the first kind of cement was added to 100 parts by weight of natural soil, followed by dry mixing. Thereafter, 30 parts by weight of water was further added thereto, followed by wet mixing to prepare a homogeneous mixture. Thereafter, nine specimens having a size of 10 cm × 20 cm were prepared and cured at 20 ° C., and the strength was measured at 3 days, 7 days, and 28 days Respectively.

Example  One

First, the comparative example is one kinds of the specific surface area in place of the cement 4,360cm ² / g of granulated blast furnace slag fine powder relative to 100 parts by weight, the grinding treatment is 46.7% by weight a specific surface area of 2,160cm ² / g and the content of CaO, SO ₃ < / RTI > content of 16.8 wt.% Were homogeneously mixed to produce a fire.

30 parts by weight of the above fire-proofing agent was added to 100 parts by weight of natural soil, followed by dry mixing. Thereafter, 30 parts by weight of water was further added thereto, followed by wet mixing to prepare a homogeneous mixture. Thereafter, nine specimens having a size of 10 cm × 20 cm were prepared and cured at 20 ° C., and the strength was measured at 3 days, 7 days, and 28 days Respectively.

Example  2

First, the comparative example is one kinds of the specific surface area in place of the cement 4,360cm ² / g of granulated blast furnace slag fine powder relative to 100 parts by weight, the grinding treatment is 46.7% by weight a specific surface area of 2,160cm ² / g and the content of CaO, SO ₃ having a specific surface area of 3,820 cm ² / g and having a CaO content of 36.5% by weight and an SO ₃ content of 9.2% by weight % By weight of a circulating fluidized bed boiler fly ash were homogeneously mixed to prepare a fireproof product.

30 parts by weight of the above fire-proofing agent was added to 100 parts by weight of natural soil, followed by dry mixing. Thereafter, 30 parts by weight of water was further added thereto, followed by wet mixing to prepare a homogeneous mixture. Thereafter, nine specimens having a size of 10 cm × 20 cm were prepared and cured at 20 ° C., and the strength was measured at 3 days, 7 days, and 28 days Respectively.

Example  3

A specific surface area in place of the comparative example 1 kinds of cement 4,360cm ² / g of granulated blast furnace slag fine powder relative to 100 parts by weight, the grinding treatment is 46.7% by weight a specific surface area of 2,160cm ² / g and the content of CaO, SO ₃ content 50 parts by weight of a coal ash circulating fluidized bed boiler bottom ash of 16.8% by weight, 20 parts by weight of natural anhydrous gypsum and 30 parts by weight of a first kind of cement were homogeneously mixed to prepare a binder.

30 parts by weight of the above fire-proofing agent was added to 100 parts by weight of natural soil, followed by dry mixing. Thereafter, 20 parts by weight of water was further added thereto, followed by wet mixing to prepare a homogeneous mixture. Then, 9 specimens having a size of 10 cm × 20 cm were prepared and cured at 20 ° C., and the strength was measured at 3 days, 7 days, and 28 days Respectively.

Specimen  Test methods and results

As shown in Table 1 below, the compressive strength test was carried out by the uniaxial compressive strength test method of KS F 2343. The heavy metal elution test was carried out by taking a part of the sample after measuring the compressive strength at 28 days.

Experiment Way Remarks Compressive strength KS F 2343 Uniaxial Compressive Strength Test Method Heavy metal leaching Waste process test standard Heavy metal dissolution test method

division Compressive strength 3 days
(MPa) Compressive strength 7 days
(MPa) Compressive strength 28 days
(MPa) Comparative Example 3.72 6.56 8.87 Example 1 3.76 6.64 8.98 Example 2 3.86 7.18 9.37 Example 3 4.12 8.17 10.92

(One) Uniaxial compressive strength  change

Table 1 shows the uniaxial compressive strengths of Comparative Examples and Examples 1, 2 and 3. As can be seen from the results, Example 1 using the blast furnace slag fine powder and the circulating fluidized bed boiler bottom ash exhibited almost the same strength as Comparative Example 1 using the first grade cement, and further including the circulating fluidized bed boiler fly ash Example 3, which further comprises Example 2, natural anhydrous gypsum and one kind of cement, shows higher strength than all of the comparative examples using only one type of cement at all ages. Therefore, it can be seen that the environmentally friendly fireproofing of the present invention is capable of replacing the first type cement used in the surface layer mixing treatment of soft ground and the soil pavement method.

(2) Extraction of heavy metals

KSLT Hexavalent chromium Copper Mercury cadmium lead arsenic Acceptance criteria 1.5 3.0 0.005 0.3 3.0 1.5 Comparative Example 1 0.843 0.247 Non-detection 0.159 0.245 0.133 Example 1 Non-detection Non-detection Non-detection 0.008 Non-detection Non-detection Example 2 Non-detection Non-detection Non-detection Non-detection Non-detection Non-detection Example 3 Non-detection Non-detection Non-detection Non-detection Non-detection Non-detection

The results of the heavy metal leaching experiment shown in Table 3 show that the comparative example satisfies the allowable reference value, but in the case of hexavalent chrome, the amount exceeding 50% of the reference value is eluted. All of the examples of the present invention, however, did not detect any heavy metals as well as hexavalent chromium.

 Therefore, the soft ground surface layer mixing treatment and the soil pavement method of the present invention can be used as a stimulant for the fine powder of blast furnace slag powder in the circulating fluidized bed boiler to replace the one kind of common cement most widely used in construction work Or the amount thereof can be minimized. In addition, it is an eco-friendly method that can solve the problem of natural resource and energy exhaustion, carbon dioxide emission, and environmental pollution caused by the release of harmful heavy metals, as well as production cost reduction by cement usage reduction.

Claims (5)

1) producing a solidified flame containing a blast furnace slag fine powder and a circulating fluidized bed boiler bottom ash;
2) adding 5 to 200 parts by weight of the fireproofing material to 100 parts by weight of the soil material;
3) uniformly mixing the gravel and the fire;
4) installing and setting up a mixture of soil and solid fire; And
And 5) curing a mixture of the gypsum and the solidified gypsum.
The method according to claim 1,
In the step 1), 5 to 700 parts by weight of the bottom fluid ash of the circulating fluidized bed boiler is added to 100 parts by weight of the blast furnace slag fine powder,
Wherein the circulating fluidized bed boiler bottom ash has a CaO content of 15 to 75 wt% and an SO ₃ content of 3 to 30 wt%.
3. The method of claim 2,
The method according to any one of claims 1 to 3, further comprising 0.5 to 400 parts by weight of a circulating fluidized bed boiler fly ash having a CaO content of 10 to 55% by weight based on 100 parts by weight of the blast furnace slag fine powder. Mixing treatment and soil packing method.
3. The method of claim 2,
In the step 1), the solidifying agent may further contain 0.5 to 400 parts by weight of a sulfate stimulant based on 100 parts by weight of the blast furnace slag fine powder,
Wherein the sulfate stimulant further comprises any one or a mixture of two or more of natural anhydrous gypsum, petro coke desulfurization gypsum, and gypsum discharged from a steel mill.
The method according to claim 1,
In the step 1), the cement comprises 0.5 to 200 parts by weight of cement based on 100 parts by weight of the blast furnace slag fine powder,
Wherein the cement further comprises one or more of a first type cement, a third type cement, a CSA (Calcium Sulfur Aluminate), a blast furnace slag cement and a fly ash cement, or a mixture of two or more thereof.