KR102125577B1 - Composition agent - Google Patents

Abstract

The present invention relates to a binder composition using a circulating fluidized bed boiler bottom ash as a stimulant, and more specifically, a bottom ash discharged from a circulating fluidized bed boiler is used as a stimulant of fine blast furnace crushed slag powder to improve the activity of fine blast furnace crushed slag powder. It relates to a binder composition that can replace the most widely used type of ordinary cement or minimize the amount used.
The binder composition using the circulating fluidized bed boiler bottom ash as a stimulator according to the present invention is discharged from the bottom of the circulating fluidized bed boiler (Circulating Fludized Bed Combustion) with respect to 100 parts by weight of the blast furnace crushed slag powder and has a CaO content of 15 to 70% by weight and SO ₃ It is characterized in that it contains 5 to 700 parts by weight of the bottom ash having a content of 3 to 30% by weight.

Description

Binder composition using circulating fluidized bed boiler bottom ash as a stimulant{COMPOSITION AGENT}

The present invention relates to a binder composition using a circulating fluidized bed boiler bottom ash as a stimulant, and more specifically, a bottom ash discharged from a circulating fluidized bed boiler is used as a stimulant of fine blast furnace crushed slag powder to improve the activity of fine blast furnace crushed slag powder. The most widely used type of construction relates to a binder composition capable of replacing ordinary cement or minimizing the amount used.

About 8% of the emissions of CO _2, which accounts for 55% of the greenhouse gases has been counted to be discharged from the cement manufacturing. As a normal cement is produced through a melting process at a high temperature (about 1,450℃), it consumes a large amount of energy. When producing 1 ton of cement, limestone is about 1.13 tons, and bituminous coal required for calcination of clinker is about 130kg. Is consumed. Accordingly, the amount of carbon dioxide emitted is about 0.50 ton in the calcination stage of limestone, and about 0.40 ton in the calcination process through the combustion of fossil fuel, and eventually, about 0.9 ton of carbon dioxide is emitted every time one ton of cement is produced. Therefore, the reduction of greenhouse gases will emerge as the biggest issue in the cement industry.

Therefore, it is urgent to develop a technology that can minimize the amount of cement used, and the cement industry is expected to reduce the production of cement clinker by 50% or more. However, the world's cement demand is expected to increase by 2.5~5.8% every year until the beginning of the 21st century, and it is necessary to develop cement with little or no carbon dioxide emission in order to simultaneously meet the Kyoto Protocol and increase the demand for cement. Do. As a countermeasure against this, if the amount of cement can be minimized and a binder capable of exerting the same level of performance as cement by using various industrial by-products can be produced, it will not only reduce production costs, but also deplete natural resources and energy and pollute the environment due to carbon dioxide emissions. It is expected to solve the problem at the same time.

In the case of fly ash, which accounts for about 80% of coal combustion by-products emitted from a coal-fired boiler of a thermal power plant (Pulverized Combustion), when it is burned at a high temperature of about 1,350℃, a glassy (amorphous) component is generated to show pozzolanic reactivity. It is used as a concrete raw material, and the bottom ash, which is about 20% of the amount of by-products, is also attached to the furnace wall when pulverized coal is burned, and refers to coal ash that has fallen to the bottom of the boiler under its own weight. It is a porous material containing a large amount. The pulverized coal boiler bottom ash has a particle size similar to that of fine aggregates and coarse aggregates for concrete, and is included in KS F 2534;2009 structural lightweight aggregate, so it is evaluated to have lightness and rigidity enough to be used as a lightweight structural aggregate. Research to utilize this as an aggregate is being actively conducted.

In addition, recently, there has been actively researched to develop the geopolymer polymerization reaction by destroying the glassy film of the bottom ash with chemicals such as sodium hydroxide after physically activating it by pulverizing the bottom ash of the pulverized coal boiler in the thermal power plant into ultrafine particles. Is in progress. In this regard, the Republic of Korea Registered Patent No. 133933 "Binder containing a bottom ash" and 1410056 "Bottomless concrete with a binder containing a bottom ash" and No. 1366293 "Blast cement slag and bottom ash consisting of bottom ash In the concrete composition comprising, sleepers using the same and a method for manufacturing the same, a technique for inducing a geopolymer polymerization reaction by pulverizing the bottom ash of a pulverized coal boiler in a thermal power plant is proposed. In addition, in Korean Patent Registration No. 1256256, "Binder composition for concrete containing bottom ash", the bottom ash was finely pulverized to 6,000 to 8,000 cm ² /g by vibrating mill to activate the particle surface and suggest the possibility of use as a cement mixture. . All of the above patents are intended to utilize the bottom ash of the pulverized coal boiler of the thermal power plant.

On the other hand, coal-fired by-products discharged from a circulating fluidized bed boiler of a small and medium-sized cogeneration plant have a low combustion temperature of about 850°C, so that no glassy substance is formed, so pozzolanic reactivity is not present. In addition, the recycled fluidized bed boiler fly ash has a higher CaO and SO ₃ content and a lack of SiO ₂ content than the fly ash discharged from the pulverized coal boiler, but recycling is not suitable, but as the fly ash standard of KS L 5405;2015 was revised, the fly ash of the pulverized coal boiler Recycling measures were prepared to be mixed with and partially used. However, the bottom ash of the circulating fluidized bed boiler has no special application method and is considered as an aggregate, but it is difficult to utilize as a lightweight aggregate like the pulverized coal boiler bottom ash because it has a very small size and fine porosity compared to the pulverized coal boiler bottom ash. It is a situation in which the entire amount of landfill is being processed. Moreover, some research data on the bottom ash of the pulverized coal-fired boiler in the cogeneration power plant or the pulverized coal boiler in the thermal power plant has been reported, but no research data has been reported on the bottom ash of the circulating fluidized-bed boiler.

Meanwhile, in order to reduce the use of portland cement, a technique using an alkali activated slag and a geopolymer polymerization has recently been proposed. These technologies include glassy (amorphous) materials such as NaOH, KOH, Na ₂ CO ₃ , and Na ₂ SiO ₃ that can be activated glass, such as blast furnace ash slag powder and pulverized coal boiler fly ash and bottom ash containing a large amount of glassy components. Studies have been reported that it is possible to make a binder that is highly irritating with chemicals and exhibits the same properties as general cement and has high water tightness and heat resistance. However, these alkali-activated slag and geopolymers are economically vulnerable because the drugs used as stimulants are too expensive, and due to the characteristics of the strength-expressing mechanism, they are easily carbonized, and thus, the durability is weak, and the stimulants are strong enough to exceed the pH of 13 Since it has strong alkali, it is a deliquescent raw material that easily dissolves when exposed to the atmosphere, and has a problem of being liquefied and used because it is difficult to handle as a powder.

Therefore, the main raw material is limestone, clay, iron ore, and is manufactured by thermal decomposition at high temperature using coal as a fuel, that is, it is a product that has serious damage to natural resources and nature, and it uses the amount of cement, a product that emits a large amount of CO ₂ gas in the manufacturing process. It is necessary to develop an eco-friendly binder that is environmentally friendly, has excellent durability, and does not elute alkali metal salts while minimizing.

Republic of Korea Patent Registration No. 10-1339332 Republic of Korea Patent Registration No. 10-1410056 Republic of Korea Patent Registration No. 10-1366293 Republic of Korea Patent Registration No. 10-1312562

The present invention was devised to solve the above-mentioned problems, and the object of the present invention is to improve the activity of the fine blast furnace slag fine powder by utilizing the bottom ash discharged from the bottom of the circulating fluidized bed boiler as a stimulant to the fine blast furnace slag fine powder. It is to provide a binder composition that can replace one of the most widely used common cement.

In order to solve the above technical problem, the binder composition using the circulating fluidized bed boiler bottom ash as a stimulant is discharged from the bottom of the circulating fluidized bed combustion, with respect to 100 parts by weight of the fine powder of the blast furnace crushed slag, and has a CaO content. 15 to 70% by weight and 3 to 30% by weight of SO ₃ is characterized in that it contains 5 to 700 parts by weight of the bottom ash.

Further, the granulated blast furnace slag fine powder relative to 100 parts by weight of a circulating fluidized bed boiler fly ash, 0.5 to 200 parts by weight further includes a, and the circulating fluidized bed boiler fly ash is circulated as discharged from the fluidized bed boiler dust collector SiO ₂ content of 10 to 45 wt. %, the CaO content is 10 to 55% by weight, and the SO ₃ content is preferably 3 to 20% by weight.

In addition, with respect to the granulated blast furnace slag fine powder 100 parts by weight of a pulverized coal boiler fly ash and further comprises 0.5 to 100 parts by weight of the pulverized coal boiler fly ash has a SiO ₂ content of 35 as discharged from the power plant pulverized coal boiler (Pulverized Combustion) dust collector It is preferred that ˜60 wt%, CaO content is 0.5-10 wt% and SO ₃ content is 0.1-3 wt%.

In addition, with respect to 100 parts by weight of the fine powder of the blast furnace slag, 0.5 to 200 parts by weight of gypsum is further included, and the gypsum further includes any one or two or more mixtures of natural gypsum, flue gas desulfurization gypsum, and petrol coke desulfurization gypsum. desirable.

In addition, with respect to 100 parts by weight of the blast furnace crushed slag powder, 0.5 to 200 parts by weight of cement is further included, and the cement is any one of one type of cement, three types of cement, Calcium Sulfur Aluminate (CSA), blast furnace slag cement, and fly ash cement. It is preferred to further include one or more mixtures.

According to the present invention, by utilizing the bottom ash of the circulating fluidized bed boiler, which is insufficiently utilized, as a stimulant, it enhances the activity of the fine powder of the blast furnace crushed slag, thereby replacing one of the most widely used common cements in construction work or minimizing the use thereof. have.

In addition, it is possible to simultaneously solve the problem of depletion of natural resources and energy and environmental pollution caused by carbon dioxide emission, as well as reduction of production cost due to reduction of cement usage.

Hereinafter, the binder according to the present invention will be described in detail.

The binder composition according to the present invention is discharged from the bottom of the circulating fluidized bed boiler with respect to 100 parts by weight of the fine powder of the blast furnace crushed slag and has a CaO content of 15 to 70% by weight and an SO ₃ content of 3 to 30% by weight of bottom ash 5 to 700 parts by weight Includes.

The blast furnace crushed slag is a by-product of rapid cooling of slag in a hot melt state generated as a by-product in the steel blast furnace process. The fine powder of the blast furnace crushed slag is called a latent hydraulic material because the fine powder of the blast furnace crushed slag does not hydrate itself by forming an amorphous film upon contact with water. The amorphous film must be destroyed in order for the latent hydraulic properties to be exhibited. The fine powder of the blast furnace crushed slag can be used as long as it is a commercially available product with a specific surface area of 3,000 cm ² /g or more.

The bottom ash is generated at the bottom of the boiler in a method of mixing with limestone in a circulating fluidized bed boiler using coal as a main fuel and desulfurizing the furnace. In the desulfurization process of a circulating fluidized bed boiler, limestone is injected into the combustion chamber and burned together with fuel, so that sulfur phosphate and limestone in the combustion gas react in the furnace to remove sulfur in the combustion gas and anhydrous gypsum. It is carbonated, transferred to the raw lime component, and discharged. In particular, the bottom ash of the circulating fluidized bed boiler can not cause a pozzolanic reaction because it is burned at a temperature of about 850°C and does not have a glassy component, but it contains higher CaO and CaSO ₄ components than fly ash collected from the top and blast furnace slag. It can be said that it has a more excellent composition as a stimulant of fine powder. Therefore, when the pH is 11.5 or higher and is used as a fine powder of blast furnace crushed slag, it has a property that can act as a stimulant.

When water is added to the fine blast furnace slag fine powder, an amorphous film is formed on the surface, so that there is no elution such as Ca ²⁺ , Al ³⁺ inside. However, when water is added after mixing the bottom ash of the circulating fluidized bed boiler, the CaO component contained in the bottom ash reacts with water to be converted to Ca(OH) ₂ and generated OH ^- and SO ₄ ² generated during the desulfurization process. ^-The component breaks the amorphous film of the blast furnace crushed slag fine powder to facilitate the elution of Ca ²⁺ , Al ^3+, etc., and the elution ions produce CaO-SiO ₂ -H ₂ O-based hydrates to accelerate curing. In addition, the surplus sulfur oxide improves the compressive strength of the cured body by densifying the structure inside the hydration body by generating ethrinite hydration products (3CaO·Al ₂ O ₃ ·3CaSO ₄ ·32H ₂ O) having a needle-like structure. Can.

When the bottom ash has a particle diameter of 5 mm or less, some fine powders exist, and thus have a stimulating effect of blast furnace crushed slag itself, so it can simultaneously play a role as a stimulant and fine aggregate, so it can be used directly as a paste and mortar when mixed with water. Do. However, in order to further improve the stimulation effect of the blast furnace crushed slag, it is preferable to use it by pulverizing to 1 mm or less.

The bottom ash preferably has a CaO content of 15 to 70% by weight. If the content is less than 15% by weight, CaO content existing in the form of CaCO ₃ and CaSO ₄ is insufficient except for about 10% by weight of CaO. That is, since the pure CaO reacts with water and is converted to Ca(OH) ₂ , the amount of OH ^- ions generated is insufficient, so it is difficult to break the amorphous film of the blast furnace water-slag fine powder in a short time and the initial strength is greatly reduced. In addition, the pure CaO present in the bottom ash reacts with water to absorb, exothermic, and expand to become Ca(OH) ₂ , the reaction formula is as follows, and 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 and then acts as an alkali stimulant of the blast furnace crushed slag fine powder after the transition to calcium hydroxide, but promotes the hydration reaction of the fine blast furnace slag fine powder by increasing the temperature due to heat generation, and compensates for the volume shrinkage of the hardened body and prevents neutralization. Roles, etc. will be played at the same time. On the contrary, if the CaO content is more than 70% by weight, the CaO content existing in the form of pure CaO is excessive, absorbing moisture excessively, and exotherm and expansion may occur excessively to cause cracking. Therefore, in the bottom ash, a chemical quantitative analysis must be performed before the raw material is received, and a CaO content of 15 to 70% by weight should be used.

The bottom ash is preferably 3 to 30% by weight of SO ₃ content. If it is less than 3% by weight, it is difficult to express strength due to insufficient content of SO ₃ capable of stimulating the slag, and if it exceeds 30%, there may be an excess amount of SO _{3 that} does not react with slag, so the strength may be lowered. It is preferable to use the bottom ash within the above range by analyzing the chemical composition.

The bottom ash is preferably mixed with 5 to 700 parts by weight with respect to 100 parts by weight of the fine powder of the blast furnace crushed slag. If it is less than 5 parts by weight, the effect is not exhibited. Excessively, the strength is greatly reduced.

In addition, with respect to 100 parts by weight of the fine powder of the blast furnace slag, 0.5 to 200 parts by weight of a circulating fluidized bed boiler fly ash is further included, and the circulating fluidized bed boiler fly ash has an SiO ₂ content of 10 to 45% by weight and a CaO content of 10 to 10 parts by weight. 55% by weight, SO ₃ content is 3 to 20% by weight and is preferably discharged from a circulating fluidized bed boiler dust collector. The circulating fluidized bed boiler fly ash is discharged from a thermal power plant or a combined heat and power plant equipped with desulfurization facilities in the furnace, and limestone is mixed and burned with coal and other auxiliary fuels, so that the CaO content and SO ₃ content in the desulfurization and desulfurization process of lime is higher than pH 11.5. It is discharged as a high-alkali substance and acts as a stimulant for blast furnace slag.

The circulating fluidized bed boiler fly ash is preferably mixed in an amount of 0.5 to 200 parts by weight based on 100 parts by weight of the fine powder of the blast furnace crushed slag. If it is less than 0.5 part by weight, the effect is not exhibited. Since the amount of is relatively reduced, the latent hydraulic property decreases and the CaO component increases relatively, so that a large amount of water is absorbed and fluidity may decrease.

In addition, with respect to 100 parts by weight of the fine powder of the blast furnace slag, the coal power plant further comprises 0.5 to 100 parts by weight of the fly ash boiler fly ash, and the fly ash boiler fly ash has an SiO ₂ content of 35 to 60% by weight and a CaO content of 0.5 to 10% by weight, SO ₃ content is 0.1 to 3% by weight and is preferably discharged from the pulverized coal boiler dust collection equipment. The fly ash of the pulverized coal boiler is a circuit collected when the combustion gas of the pulverized coal combustion boiler passes through the dust collector in a thermal power plant equipped with a separate desulfurization facility, and the pH is 6~11 because the CaO content is less than 10% by weight. It is a neutral and low alkali substance.

Fly ash, a coal-fired boiler of a thermal power plant, is partially substituted for Portland cement. Fly ash has a spherical particle, which increases fluidity and has pozzolan reactivity, which increases strength in the long-term age, but hardens itself to harden in the early age. . That is, when mixed with Portland cement, after the formation of calcium hydroxide, a hydration product of cement, the fly ash is stimulated and cured by this. For this reason, the reaction of the fly ash starts secondarily, and for this reason, it poses problems such as delayed condensation, initial strength reduction, and neutralization when using fly ash mixture in Portland cement. Due to these phenomena, problems such as delay in mold demolding time, deterioration of initial strength, and deterioration of long-term durability due to neutralization may occur at the construction site, so the content of fly ash compared to 100% by weight of Portland cement is used at 5 to 20% by weight. . In the present invention, the pozzolanic reaction of the fly ash of the pulverized coal boiler is initially activated by the stimulating effect of Ca(OH) ₂ generated by the CaO component of the circulating fluidized bed boiler bottom ash reacting with water.

The pulverized coal boiler fly ash is preferably mixed in an amount of 0.5 to 100 parts by weight based on 100 parts by weight of the fine powder of the blast furnace crushed slag. If it is less than 0.5 parts by weight, the effect is not exhibited. There is a large amount of fly ash, so the strength is greatly reduced.

In addition, in order to improve the activity of the blast furnace crushed slag, 100 to parts by weight of the blast furnace crushed slag, 0.5 to 200 parts by weight of gypsum, natural gypsum, flue gas desulfurization gypsum, Petro Coke desulfurization gypsum, any one or two or more mixtures It is preferred to further include. The gypsum is preferably mixed with 0.5 to 200 parts by weight with respect to 100 parts by weight of the fine powder of the blast furnace crushed slag. If less than 0.5 part by weight, the effect is not exhibited, and when it exceeds 200 parts by weight, a large amount of gypsum components that do not react with the slag exists Therefore, the strength is greatly reduced.

In addition, in order to improve the initial strength, 100 parts by weight of the fine powder of the blast furnace crushed slag, 0.5 to 200 parts by weight of cement is further included, and the cement is one type of cement, three types of cement, superhard steel cement, CSA (Calcium Sulfur Aluminate) , It is preferable to further include any one or a mixture of two or more of blast furnace slag cement, fly ash cement. The cement is preferably mixed with 0.5 to 200 parts by weight with respect to 100 parts by weight of the fine powder of the blast furnace crushed slag. If it is less than 0.5 parts by weight, the effect is not exhibited, and when it exceeds 200 parts by weight, the initial strength increases, but hexavalent chromium, etc. Hazardous ingredients can be eluted and economic efficiency is also insufficient.

Preferred and comparative examples of the present invention will be described below. In addition, the following examples are intended to illustrate the invention and should not be understood as limiting the scope of the invention.

Comparative example

Marine clay by sufficient mixing to 1m 1 species ^third reference cement 400kg, bentonite 20kg, forced mixer, the water 410kg to prepare a milk juipjae mixed homogeneously with marine clay 1m ^3,? 10cm? Produce a specimen 9 of 20cm size It was then cured at 20°C to measure the strength at 3, 7 and 28 days of age. The permeability coefficient was performed before measuring the compressive strength at 7 days of age.

Example One

A specific surface area of 2,160cm ² /g and a CaO content of 46.7% by weight, SO, by pulverizing the 100 parts by weight of blast furnace crushed slag fine powder having a specific surface area of 4,360cm ² /g as a commercial product in place of the first type cement of the comparative example _{3 A} binder was prepared by homogeneously mixing 80 parts by weight of the bottom ash of a coal fired circulation fluidized bed boiler having a content of 16.8% by weight.

This is mixed with 400 kg of the binding material and 410 kg of water with a forced mixer, based on 1 m ^{3 of} marine clay, to prepare a milk injection material, and homogeneously mixed with 1 m ^{3 of} marine clay, to produce 9 specimens of ?10 cm to 20 cm size and to produce 20 It was cured at ℃ ℃ 3, 7 days, 28 days to measure the intensity. The permeability coefficient was performed before measuring the compressive strength at 7 days of age.

Example 2

The comparative example is one kinds of the specific surface area in place of the cement is commercially available products with respect to a granulated blast furnace slag fine powder 100 parts by weight of 4,130cm ² / g, a specific surface area by pulverizing process and 2,160cm ² / g, 46.7 wt% of CaO content, SO ₃ Coal-fired circulating fluidized bed boiler with a content of 16.8% by weight, 60 parts by weight of bottom ash, specific surface area of 3,820cm ² /g, CaO content discharged from a coal-fired circulating fluidized-bed boiler dust collecting facility is 36.5% by weight, SO ₃ content is 9.2% by weight A binder was prepared by homogeneously mixing 30 parts by weight of the circulating fluidized bed boiler fly ash.

This is mixed with 400 kg of the binding material and 410 kg of water with a forced mixer, based on 1 m ^{3 of} marine clay, to prepare a milk injection material, and homogeneously mixed with 1 m ^{3 of} marine clay, to produce 9 specimens of ?10 cm to 20 cm size and to produce 20 It was cured at ℃ ℃ 3, 7 days, 28 days to measure the intensity. The permeability coefficient was performed before measuring the compressive strength at 7 days of age.

Example 3

The comparative example is one kinds of the specific surface area in place of the cement is commercially available products with respect to a granulated blast furnace slag fine powder 100 parts by weight of 4,130cm ² / g, a specific surface area by pulverizing process and 2,160cm ² / g, 46.7 wt% of CaO content, SO ₃ 150 parts by weight of the bottom ash of a coal-fired circulating fluidized bed boiler having a content of 16.8% by weight, a specific surface area of 3,450cm ² /g, a SiO ₂ content discharged from a coal-fired pulverized coal boiler dust collection facility, 51.2% by weight, and a CaO content of 1.9% by weight And a SO ₃ content of 0.8% by weight of pulverized coal boiler fly ash 30 parts by weight, 50 parts by weight of coke desulfurized gypsum, and 30 parts by weight of one type of cement were mixed homogeneously to prepare a binder.

This is mixed with 400 kg of the binding material and 410 kg of water with a forced mixer, based on 1 m ^{3 of} marine clay, to prepare a milk injection material, and homogeneously mixed with 1 m ^{3 of} marine clay, to produce 9 specimens of ?10 cm to 20 cm size and to produce 20 It was cured at ℃ ℃ 3, 7 days, 28 days to measure the intensity. The permeability coefficient was performed before measuring the compressive strength at 7 days of age.

Public Test method and result

As shown in Table 1 below, the permeability coefficient was carried out according to the KS F 2322 variable gas permeability test method, and the compressive strength test was conducted by the KS F 2343 uniaxial compressive strength test method. The heavy metal dissolution test was conducted after 28 days of compressive strength measurement.

Experiment Way Remark Permeability coefficient KS F 2322 Variable permeability test method Compressive strength KS F 2343 Uniaxial compression strength test method Heavy metal elution Waste process testing standards Heavy metal dissolution test method

(1) Permeability coefficient

Table 2 shows the permeability coefficient test results of the specimen cured at 20°C for 7 days. As can be seen in Table 2, a satisfactory result was obtained by constructing an impermeable layer in all specimens, and it can be seen that the permeability coefficient of the examples of the present invention is lower than that of the comparative examples, which is hydrated when one type of cement and bentonite of the comparative examples are used. As the volume shrinkage generated during the reaction and the moisture contained in the specimen evaporate or hydrate, the water permeability coefficient is relatively large, and in the case of the binder according to the present invention, the tissue becomes dense by the hydration reaction of blast furnace crushed slag fine powder and circulating fluidized bed boiler bottom ash It is judged that the unit water is reduced and the expansion occurs in the constrained state due to the water absorption action of CaO present in the circulating fluidized bed boiler bottom ash and fly ash, and the tissue is compacted by the chemical prestressing action, thus showing relatively low water permeability.

division Permeability coefficient (cm/sec) Compressive strength 3 days
(MPa) Compressive strength 7 days
(MPa) Compressive strength 28 days
(MPa) Comparative example 4.32 × 10 ^-6 0.71 1.56 2.87 Example 1 5.72 × 10 ^-7 0.76 1.64 2.89 Example 2 4.93 × 10 ^-7 0.86 2.18 3.37 Example 3 4.05 × 10 ^-7 1.12 2.57 3.92

(2) Uniaxial compression strength change

Table 2 shows the uniaxial compression strength of Comparative Example and Example 1, Example 2 and Example 3. As can be seen from this, Example 1 using blast furnace crushed slag fine powder and circulating fluidized bed boiler bottom ash exhibited almost the same strength as Comparative Example 1 using one type of cement, and further comprising circulating fluidized bed boiler fly ash. Example 2 and the pulverized coal boiler fly ash, Petro coke desulfurization gypsum and Example 3, which further contains one type of cement, were found to exhibit higher strength than the comparative example using only one type of cement at all ages. Therefore, it was found that the binder of the present invention is capable of exerting performance capable of replacing one type of cement.

(3) Heavy metal dissolution experiment

Looking at the results of the heavy metal dissolution experiment in Table 3 below, the comparative example shows that it satisfies the acceptable standard, but in the case of hexavalent chromium, an amount exceeding 50% of the standard was eluted. However, in all of the examples of the present invention, most heavy metals as well as hexavalent chromium were not detected.

Therefore, the binder of the present invention replaces one of the most widely used common cements in construction work or minimizes its use by enhancing the activity of fine powder of blast furnace crushed slag by utilizing industrial by-products generated in large quantities in a circulating fluidized bed boiler of a cogeneration plant as a stimulant. Can. In addition, it is possible to simultaneously solve the problem of depletion of natural resources and energy and environmental pollution caused by carbon dioxide emission, as well as reduction of production cost due to reduction of cement usage.

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 0.873 0.231 Non-detection 0.051 0.345 0.234 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 0.082 Non-detection Non-detection Non-detection Non-detection

Claims (5)

With respect to 100 parts by weight of fine powder of blast furnace crushed slag,
Contains 15 to 45% by weight of CaO and 5 to 700 parts by weight of bottom ash to stimulate the fine powder of the blast furnace crushed slag, including 10 to 30% by weight of SO ₃ ,
The bottom ash is generated in the lower portion of the circulating fluidized bed boiler (Circulating Fludized Bed Combustion), which uses coal as fuel and mixes with limestone to desulfurize the furnace,
The bottom ash is a binder composition characterized in that the discharged from the bottom of the circulating fluidized bed boiler is finely pulverized to have a particle diameter of 0.01 to 1 mm.
According to claim 1,
The blast furnace crushed slag fine powder further comprises 0.5 to 200 parts by weight of the circulating fluidized bed boiler fly ash,
The circulating fluidized bed boiler fly ash is discharged from the circulating fluidized bed boiler dust collecting facility, and has a SiO ₂ content of 10 to 45% by weight, a CaO content of 10 to 55% by weight, and a SO ₃ content of 3 to 20% by weight. Composition.
According to claim 1,
The blast furnace water slag fine powder further comprises 0.5 to 100 parts by weight of the fine coal boiler fly ash,
The pulverized coal boiler fly ash is discharged from a pulverized coal boiler of a thermal power plant and has a SiO ₂ content of 35 to 60% by weight, a CaO content of 0.5 to 10% by weight, and an SO ₃ content of 0.1 to 3% by weight. Characterized in that the binder composition.
According to claim 1,
With respect to 100 parts by weight of the fine powder of the blast furnace crushed slag, gypsum further comprises 0.5 to 200 parts by weight,
The gypsum is a natural gypsum, flue gas desulfurization gypsum, Petro Coke desulfurization gypsum, any one or more mixture of two or more, characterized in that the binder composition.
According to claim 1,
With respect to 100 parts by weight of the fine powder of the blast furnace slag, it further contains 0.5 to 200 parts by weight of cement,
The cement is one type of cement, three types of cement, CSA (Calcium Sulfur Aluminate), blast furnace slag cement, a binder composition further comprising any one or more mixtures of fly ash cement.