KR101438060B1 - Concrete mixture for base course of the road using the reclaimed coal ash and recycled aggregate and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a recycled road base concrete mixture using reclaimed coal ash and a recycled aggregate for simultaneously solving the resource recycling and environmental problems by using reclaimed coal ash and a recycled aggregate, which are by-products of a thermal power plant, as a road pavement material. The recycled road base concrete mixture using reclaimed coal ash and a recycled aggregate according to the present invention includes: a reclaimed coal ash aggregate, a recycled aggregate, a binder, an admixture, a chloride protection agent, an emulsion asphalt and a rejuvenator.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recycled aggregate for recycled aggregate and recycled aggregate,

The present invention relates to a recycled concrete mixture for a road base layer, and more particularly, to a recycled aggregate for a road base layer, and more particularly to a recycled aggregate for recycling of construction waste, which is a byproduct of a thermal power plant, The present invention relates to a recycled concrete mixture for a road base layer using a reclaimed aggregate and a recycled aggregate, and a method for producing the same.

The cross section of the road pavement is divided into the sign, base layer, auxiliary layer, and embankment layer. When the surface layer is packed after the base layer is formed, asphalt, concrete and various additives are mixed in the plant or field in the aggregate, It is distinguished by high temperature type, medium temperature type and normal temperature type according to the mixing temperature condition.

High-temperature asphalt-concrete road pavement method is mostly used for road pavement. However, asphalt is heated during road pavement, so volatile organic compounds (VOC) and odor are generated. In addition, By generating carbon dioxide, which is a gas, a great deal of burden is placed on the amount of carbon dioxide generated in road construction and packaging, and a solution is urgent.

On the other hand, the method of recycling waste asbestos, a room-temperature recycled concrete road pavement method, has no degradation or oxidation of asphalt binders that can occur during the heating process. Compared with the heating type, the air pollution and the generation of carbon dioxide due to the generation of volatile organic compounds And there is a great effect in energy saving effect and resource saving. In addition, waste asbestos can be recycled into room temperature pavement by recycling waste ascon to a large extent so that it meets the purpose and purpose of recycling.

On the other hand, the landfill, which is a combustion by-product of the coal-fired power plant, means that the ash generated during the burning process of coal in the boiler is dropped and discharged to the bottom of the boiler by the load and then treated dry or wet. Most of them are cooled by seawater and then transported and buried in the landfill. The landfill is called bottom ash or bottom ash, but it is made up of 10 to 20% fly ash and 80 to 90% bottom ash and cinder ash.

Currently, 9 million tons of coal is emitted each year, and technologies for recycling by-products of domestic coal-fired power plants, which are expected to continuously increase their emissions in the future, are being developed. For recycling purposes, concrete mixes, cement clinker replacement, Road aggregate, embankment aggregate, and drainage aggregate.

Among the byproducts of thermal power plants, fly ash is highly concentrated in cement substitutes, concrete admixtures and concrete products, but it has a high recycling rate of 85%. However, the recycling rate of bottom ash is less than 20%, and the buried building, which continues to accumulate, puts a lot of environmental burden on the power plant.

Conventional flooring material recycling technology is generally used as fine aggregate for concrete compounding. Patent registration method (patent registration No. 482378) for reclaim aggregate and industrial multi-functional environmental block using industrial by-products is patented. &Quot; Patent document No. 364911 ", "Concrete composition using bottom ash and method of producing the same" (Patent Registration No. 429669), "High performance concrete using bottom ash Composition and method for producing the same "(Publication No. 2005-0082083).

Also, as a technique for using flooring material as a road construction material, "Asbestos mixture using bottom ash as aggregate and its manufacturing method" (Registration No. 0796048), "Mixed embankment of buried coal ash and soil with a strength enhancement effect by lime treatment "(Application No. 2011-0055052).

The bottom material is an oxide of chemical substance such as silicon, aluminum, iron, calcium, potassium, and titanium, similar to fly ash, and has similar composition to ordinary sand. Unlike fly ash, which has a particle size of 0.5 ~ 100㎛ and similar to coarse clay granularity, the flooring is in the range of 0.5 ~ 6mm, and it belongs to the sand or ridge category because it is similar to crushed aggregate for concrete (KS F2527).

The color of the flooring is somewhat grayish-white, dark brown, etc., but the shape of the particles is sandy. The chemical composition and physical properties of the landfill are listed in Tables 1 and 2.

[Table 1] Main components of fly ash

[Table 2] Physical properties of fly ash

The bottom ash contains various pores ranging from macropores to micropores because the coal raw material or the combustion products are melted due to the high temperature during the combustion process of the coal and the generated combustion gas is trapped in the molten product, And is attached to the surface.

Due to such porous properties, the flooring material exhibits a high water absorption rate of about 6 to 8% as compared with general aggregate, which is advantageous for application to lightweight secondary concrete products and excellent water permeability. However, there is a problem that it is difficult to use the concrete as a secondary product such as a revetment block, a retaining wall block, and an artificial reef, because it is not durable and can not be used in a concrete that requires non-watertightness.

Therefore, the recycling field of flooring material is to substitute substitute for coarse aggregate (coarse aggregate) or fine aggregate (fine aggregate) as a general concrete composition, or to replace part of fine aggregate, and there is no other application field. KS F 4570: Bottom ash aggregate for precast concrete. KS F 4570: Bottom ash aggregate for precast concrete. KS F 4570: Bottom ash aggregate for precast concrete.

One of the main reasons why the landfill could not be used as a base or auxiliary layer in road pavement was the environmental pollution caused by the heavy metals contained in the flooring. In addition, other substances may be mixed in the process of landfill. First, chloride ions are inevitably flowed into the landfill due to the sea water used to cool down the floor material falling to the bottom of the boiler of the thermal power plant and to send it to the landfill.

Since chloride ions penetrate into the concrete to weaken the structure by corroding the reinforcing bars in the reinforced concrete, civil engineering buildings such as buildings and bridges are prohibited from using marine (sea sand) containing a large amount of chloride ions as fine aggregates . In other words, the concentration of chloride ion in the floors and landfills limits the use of concrete as aggregate.

Next, the coal as raw material is pulverized in the thermal power plant, and the pyrite selected in the pulverizer is mixed with the bottom ash treatment system and processed at one time.

When pyrite is incorporated into concrete aggregate, it causes corrosion of reinforcing steel of reinforced concrete and deterioration of concrete sulphate, which weakens the strength of concrete.

Therefore, in order to utilize the reclaimed aggregate as a road pavement aggregate material, the cause of weakening due to the corrosive ions must be removed.

In addition, the bottom material in the buried pavement has a higher absorption rate than the ordinary aggregate because it contains many micropores, hollows and macropores therein, which causes the compression strength to be weakened. Therefore, in order to use the landfill as a road pavement aggregate, it is necessary to overcome the weak strength as an aggregate and to provide a bonding mechanism such as hydration reaction of cement clinker to be used as a binder.

(SiO ₂ ) and alumina (Al ₂ O ₃ ) which are the main components of the flooring react with Ca (OH) ₂ at a room temperature or at a moderate temperature by cement hydration heat for a long period of time to form calcium silicate hydrate (CSH) The reaction to form a calcium aluminate hydrate (CAH) is called a pozzolanic reaction.

In order to utilize landfill as an aggregate material for road pavement, it is necessary to make such pozzolanic reaction occur uniformly in the pores of bottom ash and on the rough surface of recycled aggregate so as to be able to manifest strength through pozzolanic reaction, It is necessary to disperse asphalt, which is an important binder of the water-soluble polymer resin, with various inorganic materials such as aggregates evenly to provide a bonding force.

In order to solve the problem of weakening the concrete strength due to the chloride ion which can be mixed in the cooling, transportation and landfilling process of the flooring treatment system, there is a need for a technique of converting the chloride ion into a form in which chloride ion is not eluted. Since the solubility of halogen ions such as chlorine is high, it can be easily dissolved in general. When the chloride ion acts as a ligand for converting a coordination complex of a transition metal, it is converted into a stable form A technique of complexing by adding an appropriate transition metal material is required.

SUMMARY OF THE INVENTION The object of the present invention is to use a landfill, which is a byproduct of a thermal power plant, as a road pavement material and to overcome the technical problems that could not be used as a road pavement material until now, And to provide a method for recycling landfill that can contribute to the preservation of the land environment by solving environmental problems such as thermal power plant landfill.

In order to accomplish the above object, according to the present invention, there is provided a recycled concrete mixture for a road surface layer comprising reclaimed aggregate, recycled aggregate, binder, admixture, antiseptic agent, emulsified asphalt, and regeneration additive .

According to another aspect of the present invention, there is provided a method of manufacturing a recycled concrete mixture for a roadbed using reclaimed aggregate and reclaimed aggregate, the reclaimed aggregate being used as a coarse aggregate, Slag cement is mixed to be used as a binder, and an antiseptic agent for preventing salt corrosion and corrosion is added to produce a concrete mixture for a road base layer.

According to the recycled concrete mixture for road base layer using the reclaimed ash and recycled aggregate according to the present invention, bottom ash and reclamation as a by-product of coal-fired power plant can be used for recycling as a resource for road construction.

Unlike fly ash, unlike fly ash, bottom ash (bottom ash) can not be used as concrete admixture or cement raw material, and its use as structural concrete is limited. Therefore, there are many problems due to an increase in landfill throughput, This problem can be solved by utilizing flooring material and recycling technology according to landfill.

According to the recycled concrete mixture for road base layer using the reclaimed aggregate and the recycled aggregate according to the present invention, it is possible to expand the field of processing and recycling of construction waste and waste ascon, which is increasing day by day. In addition, there is no reduction in quality or oxidation of the asphalt binder that can occur during the heating process, and the amount of air pollution and carbon dioxide generated due to hydrocarbon generation is smaller than that of the heating type.

Particularly, the regenerated concrete mixture for road base layer using the landfill and recycled aggregate according to the present invention can improve the road performance standards such as Marshall strength, flow value, and immersion stability by controlling the content of constituent materials, In addition, there is an advantage that it can be extended to temporary surface such as a temporary road, a back road, a bicycle road, and a parking lot.

INDUSTRIAL APPLICABILITY As described above, the present invention can efficiently replace recycled resources and recycle tributary resources by effectively utilizing the recycled aggregate and recycled aggregate, solve the environmental problem of the thermal power plant, According to the present invention, a binder and a regenerating additive are mixed and stirred without heating to produce an excellent performance and an environmentally friendly asphalt concrete mixture, which can contribute to the road construction industry economy by using not only the road base layer but also the surface layer .

1 is a view showing a process flow of a method of producing a recycled concrete mixture for a road base layer using a reclaimed aggregate and a recycled aggregate according to the present invention.

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

According to the reclaimed concrete mixture for road base layer using the reclaimed ash and the recycled aggregate according to the present invention, the reclaimed aggregate having the coarse aggregate size and the recycled aggregate are used, and the undifferentiated reclaimed material, The blast furnace slag cement is used to maintain the reference Marshall stability (Marshall strength), which is the main condition of the industry standard as road base material. In order to solve the problem of weakening the concrete strength due to the chloride ion contained in the buried sludge, an anti-seizing additive is included to exhibit the anti-salt function.

As shown in FIG. 1, a method for manufacturing a recycled concrete mixture for a road base layer using a reclaimed aggregate and a reclaimed aggregate according to the present invention includes a reclaimed pre-treatment process (S100) and a recycled concrete mixture manufacturing process (S200).

First, a pre-treatment step (S100) of a buried pre-treatment step includes a step (S110) of a buried pre-treatment step of selecting a buried material passed through an environmental standard through a heavy metal leaching test in a buried waste discharged from a bottom ash treatment system of a thermal power plant; A sludge separation step (S 120) of separating the selected landfill sieves into a size of 20 mm, 10 mm, and 5 mm; A step (S 130) of separating the buried phosphorus of 5 mm or less, which is discharged from the separating step, into pyrite; (S140) of refining the buried sphygmium with the above precipitated sphygmium powder into powders of 1 mm or less using an undifferentiated facility such as a ball mill or a rod mill.

Meanwhile, in the recycled concrete mixture manufacturing process (S200), the selected recycled aggregates of 20 mm, 10 mm, and 5 mm and the recycled aggregates of 25 mm and 13 mm are charged into the mixer, ; (S220) of adding slaked lime slurry (lime oil) to the granulated slurry having a particle size of 1 mm or less and agitatingly mixing the slaked slurry into slurry cement mixed with the coarse slag cement to the mixture of the granulated slurry and the slaked lime slurry, A blast furnace slag cement charging step (S230); An admixture injecting step (S240) of injecting an admixture such as an air entraining agent (AE agent) and a water reducing agent; A step (S250) of adding an anti-seizing agent for injecting manganese dioxide powder as an agent for preventing concrete salt corrosion; And a step (S260) of adding an emulsified asphalt and a regenerating additive such as an acrylic polymer resin to the mixture to stir and mix the emulsified asphalt and the regeneration additive.

The recycled concrete mixture thus prepared is manufactured in a plant and is placed on a final road construction site to be subjected to a compaction step and a curing step.

First, the embedding pre-treatment process (S100) for pretreating the raw materials for landfill will be described in detail.

At the landfill stage (S110), leaching tests were carried out at the landfill site where the bottom ash discharged from the boiler of the thermal power plant was transferred to the landfill, and landfills satisfying the environmental standards for harmful heavy metals such as Pb, Cu, Cd, As, Hg, Select the society. As a result of the leaching test for the landfill that passed the environmental standard, the ion concentration of the heavy metal is shown in Table 3 below.

[Table 3]. Concentration of leaching of heavy metals at the landfill meeting the environmental standards

In this case, one area is the area under the 「Intellectual Law」, which is the area where the answer is, the orchard, the ranch paper, the photocopy paper, the school paper, the school paper, the ditch cow, the fish farm, the park, There are three types of landmarks: forests, salt marshes, large marshes (referring to all the mars other than the site corresponding to one area), warehouse papers, rivers, reservoirs, water papers, sports papers, amusement parks, It is the area of the factory site, the parking lot, the gas station site, the road, the railroad site, the embankment, and the hybrid site (all the mixed sites except the site corresponding to the two areas).

In the landfill separation step S120, the selected fly ash is passed through the heavy metal environment criterion in step S110, and the size of the landfill is 20 mm (S120-1), 10 mm (S120-2) , 5 mm (S120-3), and separated in order (S120)

In the step of separating pyrrhotite (S130), the 5 mm aggregate is separated (S120-3), and magnetic pyrite is removed through the magnetic separator for the remaining buried particles of 5 mm or less.

Then, in the landfill subdivision step (S140), the landfill from which the pyrite component has been removed is charged into the undifferentiated pulverizing apparatus to subdivide it to 1 mm or less. In this case, as the undifferentiated pulverizing apparatus, an apparatus for pulverizing a solid body generally such as a ball mill or a rod mill can be used, and the particle size of the powder obtained through the undifferentiated pulverizing apparatus is in a range of 20 meshes (0.9 mm) or less and 200 meshes (0.074 mm) . Table 4 below is a chart showing the particle size distribution of the granulated powder obtained by pulverizing the pulverized pulverizer.

[Table 4] Results of particle size analysis of undifferentiated landfill

Next, the recycled concrete mixture manufacturing process (S200) will be described.

In the filling step and the recycled aggregate feeding step (S210), the separated recycled aggregates of 20 mm, 10 mm and 5 mm size and recycled aggregates of 25 mm and 13 mm size are put into a mixer and mixed into a coarse aggregate. At this time, the size of the inserted aggregate corresponds to the coarse aggregate of concrete.

In the lime slurry injecting step (S220), the slaked lime slurry (lime oil) solution is preliminarily mixed in the undifferentiated landfill prepared in the landfill subdivision step (S130).

The undifferentiated buried sludge having a particle size of 20mesh or less and a particle size of 200mesh or less is combined with the slurry slurry to perform a pozzolanic reaction as shown in the following Equations 1 and 2 to form calcium silicate hydrates (CSH) and calcium aluminate hydrates , CAH).

The long-term strength can be achieved through the pozzolanic reaction.

Subsequently, in the step of injecting blast furnace slag cement (S230), a mixture of the undifferentiated landfill slurry and the slaked lime slurry is charged, and then blast furnace slag cement is charged to form a concrete mixture. Blast furnace slag cement (standard specification of slag cement: KS L5210) is a mixture of blast furnace slag and small amount of gypsum or slaked lime mixed with ordinary portland cement clinker. It contains more calcium component than general portland cement, It is suitable for expression.

In the admixture injecting step (S240), either the air entraining agent (AE agent) and the water reducing agent are added to the concrete mixture, or either one of them is added and stirred.

Air entraining agent (AE agent) and water reducing agent are added for the workability of concrete. Generally, when the unit quantity of air entraining agent (AE agent) is increased in concrete formulations, workability is excellent but strength is weak Therefore, a water reducing agent is used to prevent this.

In step S250, the blast furnace slag cement, the air entraining agent, and the water reducing agent are added, followed by a manganese dioxide powder as an anti-salt agent.

The manganese dioxide (MnO ₂ ) powder is a black powder that can be recovered from manganese nodule-like ores and manganese dry cells that are discarded after use. The size of the manganese dioxide powder is 0.5 mm or less, This makes it possible to solve the problem of weakening the strength of concrete. Manganese dioxide reacts with or complexes with chloride ions according to Equation 3 below to produce stable manganese chloride.

Then, in the step of injecting asphalt asphalt and regeneration additive (S260), regeneration additives such as emulsified asphalt and acrylic polymer liquid resin are added and stirred and mixed (S260)

Emulsified asphalt emulsifies asphalt bitumen as a surfactant and is a binder that helps bridge between aggregate and aggregate. Acrylic polymer liquid resin also helps bond between coarse aggregate, fine aggregate and various additives, It is a regenerating additive that implements water repellent function.

The concrete mixture produced through this process is stirred and mixed in the plant, and then transported to the road pavement site to form a base layer or surface layer of road pavement by laying, compaction, and curing at room temperature.

In order to secure the strength of concrete, the sum of silica (SiO ₂ ) and alumina (Al ₂ O ₃ ) components is 70 ~ 81% by weight ratio through the landfill, slaked slurry and blast furnace slag cement, .

In addition, since the calcium oxide (CaO) component in the blast furnace slag is not easily dissolved, it takes a long time to become calcium hydroxide (Ca (OH) ₂ ), and therefore calcium hydroxide is supplied in the form of calcium hydroxide slurry, .

Hereinafter, a recycled concrete mixture for a road base layer using the reclaimed aggregate and recycled aggregate according to the present invention will be described.

The mixing ratios of the constituent materials of the recycled concrete mixture for the road base layer using the reclaimed aggregate and the recycled aggregate according to the present invention are as follows.

The weight ratio of the bottom material used as the coarse aggregate, the coarse aggregate such as the recycled aggregate and the new aggregate is in the range of 80 to 94% by weight, and the weight ratio of the aggregate such as the undifferentiated reclaimed slurry and the slaked slurry and the blast furnace slag cement is 3 to 10% Lt; / RTI >

On the other hand, manganese dioxide, which is an additive for preventing salting, is added in a weight ratio of 0.3 to 4.5%, and a concrete admixture is added in a weight ratio of 0.1 to 0.5%. Also, the emulsified asphalt is added in a weight ratio of 0.5 to 4%, and the acrylic polymer resin is added in a weight ratio of 2 to 6%.

It is preferable that the weight content of the slaked lime slurry and the blast furnace slag cement in the binder including the undifferentiated landfill slurry, the slaked lime slurry and the blast furnace slag cement is 50%, and the weight content of the undifferentiated landfill is adjusted to 50%.

When the weight ratio of the binder is less than the above range, the pozzolanic reaction is insufficient and the initial and long-term strengths are lowered. If it exceeds the above range, the strength is improved but the temperature rises due to the initial hydration heat. And the economic burden of the increase is increased.

A preferred embodiment of a recycled concrete mixture for a road base layer using a reclaimed aggregate and a reclaimed aggregate according to the present invention will be described in detail by comparison with a comparative example.

The recycled concrete mixture for the road base layer using the recycled aggregate and the recycled aggregate according to the present invention includes coarse aggregate, binder, antiseptic agent, concrete admixture, emulsified asphalt, and regeneration additive.

As the coarse aggregate, 20mm, 10mm, and 5mm sized recycled aggregate and 25mm and 13mm recycled aggregate are used. In the case of the binder, undiluted buried sludge of 1 mm or less, slaked lime slurry and blast furnace slag cement (FSC) are used.

Manganese dioxide is added as an anti-salt agent and an air entraining agent (AE agent) or a water reducing agent is used as an admixture for improving concrete workability.

As the regenerating additive, an acrylic polymer resin or the like is used.

Table 5 shows the results of measuring the Marshall stability, which is the main performance index of the asphalt mixture for the road base layer, with respect to the recycled concrete mixture for road base layer using the reclaimed ash and recycled aggregate according to the present invention.

[Table 5] Recycled concrete mixture blend table for road base layer and Marshall stability test results

As shown in Table 5, the specimen 1 and specimen 2 of the recycled concrete mixture for the road base layer using the reclaimed aggregate and the recycled aggregate according to the present invention had 88% of the recycled aggregate and recycled aggregate, 6% of the binder, 0.5% Concrete admixture 0.3%, asphalt emulsion 1.2% and renewable additive 4%.

The weight ratio of the binder to the binder in the prepared specimen 1 and specimen 2 is a weight ratio of the undiluted filler of 1 mm or less, the slaked lime slurry and the blast furnace slag cement (FSC), the antihalation agent in the above table is manganese dioxide, Air entraining agent, and the recycling additive refers to an acrylic polymer resin.

The binder composition of the specimen 1 was prepared so that the sum of the slag cement (FSC) and the slag lime slurry was 4.5%, and the sum of the slag cement and the blast slag cement was 3% Was made to be 3%, which is 50% or more of the total binder.

In the comparative example, a new aggregate, that is, a normal crushed aggregate (recycled aggregate) and a recycled aggregate were used instead of a reclaimed aggregate as a coarse aggregate, and the undifferentiated recycled aggregate, slaked slurry and blast furnace slag cement (OPC), which is a conventional industrial binder, was added in an amount of 4% by weight and compared with the examples of the present invention.

Marshall stability measurement of road pavement asphalt mixture measures the maximum load until the specimen is destroyed by increasing the load on the specimen (101 mm in diameter, 63 mm in height) at a load speed of 5 cm / min at 60 ℃ , Which is a test method for evaluating the stability of an asphalt mixture and determining the optimum amount of asphalt.

According to an embodiment the Marshall Stability of the specimens 1, 2 produced in accordance with the present invention can show a high stability than both comparative example 17,5kN / cm ² as 25.3 kN / cm ² to 33.2 kN / cm ^2, respectively. This means that even with the lack of conventional cement binders, a stronger bond can be achieved using the undifferentiated landfill slurry, slaked slurry and blast-furnace slag cement.

This is because the undifferentiated reclamation furnace formed strong calcium silicate hydrate (CSH) through pozzolanic reaction with slaked lime and blast furnace slag.

The Marshall stability was measured after 7 days for the same specimen as follows: specimen 1 was 29.2 kN / cm ² , specimen 2 was 34.4 kN / cm < ² >, indicating that the long-term strength was increased.

For reference, guidelines for domestic road pavement are 3.5 kN / cm ² for the base layer, 5.0 kN / cm ² for the middle layer, and 7.5 kN / cm ² for the surface layer. The specimen 1 and specimen 2 in the above- Exceeding the guideline standards, not only the road base layer, but also the surface quality standards.

In order to determine the durability of the asphalt, the immersion residue stability test was performed on the assumption that the asphalt pavement was submerged for 48 hours or more in heavy rainfall. As a result, 78% of the specimen 1 and 85% of the specimen 2 were observed. Exceeded 75%, which is the standard of residual water immersion stability of pavement.

Through this example, the problem of weakening the strength of the concrete mixture caused by the internal pores of the reclamation aggregate, the cement paste on the surface of the recycled aggregate, and the excessive water content was overcome by using the pozzolanic reaction between the undifferentiated landfill slurry, the slaked slurry and the blast furnace slag, A concrete mixture which can be used for road base layer was prepared.

By analyzing the chlorine content of the recycled concrete mixture for the road base layer using the reclaimed ash and recycled aggregate according to the present invention and analyzing the chloride ion eluted from the sample by the leaching test, The effect of addition was investigated.

The specimen (inner diameter: 101 mm, height: 63 mm) was manufactured according to the method of manufacturing a recycled concrete mixture for a road base layer using the reclaimed ash and recycled aggregate according to the present invention and then crushed to sample around the combined paste portion around the coarse aggregate And the chlorine content was analyzed together with Comparative Example 1 and Comparative Example 2, respectively.

Chlorine analysis for solid state samples was analyzed by SEM-EDAX method. As a result of the chlorine analysis of the specimen 1 and the comparative example 1 and the comparative example 2, the average chlorine content of the three analytical samples for specimen 1 was 181 ppm and the average value of the chlorine content Was 213 ppm, and the average value of the chlorine content of the three analytical samples for Comparative Example 2 was 73 ppm.

Comparative Example 1 was prepared with the same composition and composition ratios as Sample 1, but no manganese dioxide powder as an antiseptic agent was added, so that the amount of clay aggregate containing chlorine ions and the weight of undiluted reclamation weight were relatively large, so that the chlorine content in the concrete mixture was high will be.

[Table 6] Mixing design and chlorine content of concrete mixture for chlorine ion leaching test

Each of the prepared specimen 1 and Comparative Example 1 and Comparative Example 2 was crushed, and 100 g or more of crushed powders mainly composed of the cement paste around the aggregate was precisely weighed and dissolved in a solvent (distilled water) as in the above content analysis. : 1 (W: V) in a 500 mL Erlenmeyer flask.

This mixed solution was shaken continuously for 6 hours using a shaker at room temperature and at a pressure of about 200 times per minute with an amplitude of 4 to 5 cm and then filtered with a 1.0 占 퐉 glass fiber filter paper and an appropriate amount of the filtrate was taken, Respectively.

The mixture solution was shaken for different periods to elute the chlorine ions. After shaking for 7 days, 30 days, and 90 days, a sample solution for analysis was prepared and analyzed for chloride ion concentration. Chloride ion concentration was analyzed by the silver titration method using 0.1 N silver nitrate standard solution as a chemical titration method.

The results of the chlorine ion dissolution test conducted on the specimen 1 and the comparative example 1 and the comparative example 2 through the above-described test procedure are shown in Table 7 below.

[Table 7] Chlorine content and elution rate test of concrete mixture for road base layer

The specimen 1 prepared according to the manufacturing process of the present invention was added with 0.5% by weight of the antiseptic additive, but the antiseptic additive was not added in Comparative Example 1 and Comparative Example 2.

The longer the period of shaking in the distilled water, the greater the amount of chlorine ions eluted from the specimen 1 and the comparative example 1 and the comparative example 2. However, the specimen 1 containing the antifouling agent showed the elution amount of chlorine in Comparative Example 1 and Comparative Example 2 The amount of chlorine released was 22 ppm even after 90 days.

This is only about 12% of the chlorine content of 181ppm, indicating that the antiseptic agent does not elute the chloride ion and fixes the chloride ion in the concrete mixture.

For reference, the elution amount of chlorine ion after 90 days of Comparative Example 1 was 95.8% of the total amount and the chlorine content and the chlorine elution amount of Comparative Example 2 which did not use the landfill was small, but after 90 days, Respectively.

The phenomenon of the reduction of the chloride ion elution by the antiseptics is due to the fact that the manganese dioxide (MnO2) powder used as an antiseptic agent is partially reduced to become metallic manganese, and the chloride ion having a non- and forms a cooridnative complex as a ligand.

When the reinforcing bars or steel reinforcing materials are used on the road, the corrosion of the reinforcing material can be prevented by using the effect of reducing the chlorine ion elution amount through the antifouling agent, and the problem of concrete salt due to the chloride ion in the buried concrete can be solved.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit of the invention.

Claims (13)

delete delete delete delete delete delete delete A method for producing a concrete mixture,
The recycled aggregate and the recycled aggregate are used as coarse aggregate, and the undrawn granulated slurry and slaked lime slurry and blast furnace slag cement are mixed and used as a binder, and an antiseptic agent for preventing salt corrosion is added to prepare a concrete mixture for road base layer However,
The method of producing the concrete mixture
A landfill pretreatment process for pretreating the landfill; And
A recycled concrete mixture manufacturing process,
The embedding pre-treatment process
A landfill board selection step of selecting a landfill meeting the environmental standards for heavy metals in landfill gas discharged from a thermal power plant;
A landfill separating step of separating the selected landfill according to the size;
A step of separating pyrrhotite existing in the landfill not separated in the landfill step; And
And a step of refining the buried sludge to separate the buried sludge from the buried sludge. The method for producing a concrete mixture for a road surface layer according to claim 1,
The method of claim 8, wherein the recycled concrete mixture manufacturing process comprises:
A step of injecting recycled aggregate and recycled aggregate separated in the reclaiming and separating step and mixing them into a coarse aggregate;
Adding a slaked slurry to the undifferentiated slurry and mixing the slaked slurry;
Adding a blast furnace slag cement to the mixture of the undifferentiated buried slag and the slaked slurry, and mixing the blast furnace slag cement with the coarse aggregate;
A step of injecting an admixture for admixing the admixture;
A step of introducing an antiseptic agent into the antirheumatic agent for preventing concrete salt damage; And
And a recycling additive for recycling the asphalt asphalt and the recycle additive to the reclaimed asphalt and the regenerant additive.
9. The method according to claim 8,
Wherein the selected recycled aggregate is separated into a coarse aggregate having a size of 20 mm, 10 mm, and 5 mm, and the recycled aggregate is used to produce a concrete mixture for a road base layer.
9. The method of claim 8,
And separating the pyrite contained in the buried sludge of less than 5 mm not separated in the buried sludge separation step by a magnetic separator, using the recycled aggregate and the recycled aggregate.
9. The method of claim 8, wherein the embedding subdivision step
The method for producing a concrete mixture for a road base layer using the reclaimed aggregate and the recycled aggregate according to claim 1, wherein the buried sludge is separated into particles having a diameter of 1 mm or less by using a ball mill or a rod mill.
10. The method of claim 9,
In the filling step and the recycled aggregate feeding step, recycled aggregates having sizes of 20 mm, 10 mm and 5 mm and recycled aggregates having a size of 25 mm and 13 mm are charged into a coarse aggregate,
Wherein the manganese dioxide powder is added in the step of adding the anti-salt agent, wherein the manganese dioxide powder is added.

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