KR100975358B1 - Sea structure composite including eco-friendly artificial fishing reef for reducing carbon dioxide using anti-salinity cement and sea structure composite manufactured by this - Google Patents

Abstract

PURPOSE: A marine structure composition, and a marine structure including an artificial fish reef and a wave dissipating block are provided, which can prevent damage by salt. CONSTITUTION: A marine structure composition is constituted as follows. One or 5-10 weight% among normal cement 30-50 weight%, blast furnace slag 30-50 weight%, fly ash 10-30 weight%, anhydrous plaster 4-20 weight%, slag, and red mud is mixed. One processed material 100 weight% selected among sludge of purification plant of the alum series, fly ash, and waste silica against marine structure composition 100 weight% are mixed with acid 10-14 weight% and water 100 weight% against processed material.

Description

Marine structure composition comprising eco-friendly artificial reef and sofa block using flame retardant cement for carbon dioxide reduction and marine structure comprising artificial reef and sofa block manufactured by the composition REDUCING CARBON DIOXIDE USING ANTI-SALINITY CEMENT AND SEA STRUCTURE COMPOSITE MANUFACTURED BY THIS}

The present invention relates to an marine structure composition comprising environmentally friendly artificial reefs and sofa blocks using flame retardant cement for carbon dioxide reduction, and more particularly, to prevent reinforcing corrosion, which is a skeleton of artificial reefs and sofa blocks installed in the ocean, Marine structure composition including eco-friendly artificial reef and sofa block using flame retardant cement for carbon dioxide reduction that can make roots stick quickly and create a good habitat environment, and artificial reef and sofa block manufactured by the composition It relates to an offshore structure.

In order to protect the aquatic ecosystem and the coast, artificial reefs and sofa blocks are installed in the underwater and the coast.

Artificial reefs are structures that are constructed to create a spawning ground or habitat for aquatic organisms in the water, and are generally manufactured by curing reinforced concrete in various shapes to form empty spaces inside.

The sofa block is installed on the bank of a wave or breakwater (hereinafter referred to as 'dike') and is installed on the outer port where waves are pushed. It is also called a tetrapod.

The sofa block is made of concrete to prevent loss and movement caused by waves.

However, reinforced concrete structures such as artificial reefs and sofa blocks are exposed to the marine environment periodically and over a long period of time, so that chloride ions (Cl-) present in seawater directly penetrate into the concrete, and the permeation amount is allowed (rebar corrosion critical chloride). If the amount exceeds about 1.2 kg / m3), the reinforcing steel will be corroded by electrochemical action, which will cause salt causing cracking of the coated concrete. In general, reinforcing bars reinforcement in sound reinforced concrete structures have a surface coating (1 × 10-6 mm thickness) formed by Ca (OH) 2 of pH 12.5 contained in the concrete to maintain a stable state. When anions such as Cl-, F- and S2-SO42- present in seawater penetrate or persist at high temperature, the passivation film on the steel surface is partially destroyed and corrosion starts. Of these, chloride ions (Cl-) are known to be the most harmful to corrosion of steel.

Therefore, in order to prevent the damage of marine concrete structures, the concrete standard specification recommends the use of mixed cements such as blast furnace slag cement, fly ash cement, or medium heat portland cement as specified in KS L5201. In addition, in the case of marine concrete that is constructed in a location severely affected by seawater, the quality of requirements cannot be secured only with cement-based materials. Therefore, polymer cement concrete and resin concrete using only cement and polymer, or chlorides are used.

It is proposed to use polymer-impregnated concrete impregnated with synthetic resin with pores of concrete, which is the main penetration path of ions.

However, some of these materials cannot be practically used in the construction site due to the problems of concrete manufacturing, economics and constructability, and there are few cases of actually applying them to offshore structures. In addition, when blast furnace slag cement or fly ash cement is used in marine concrete, blast furnace slag or fly ash is less responsive than cement, so the penetration resistance of chloride ions is lower than that of cement-only concrete until cement is fully hydrated. It is known. Therefore, there is a need for a practical and universally available cement composition for marine structures that can provide flame retardancy to marine concrete regardless of when it is exposed to the marine environment.

The present applicant has patented a flame retardant cement composition (Patent No. 0654095) having high resistance to the penetration of chloride ions in a salty environment such as a marine environment.

According to the conventional flame retardant cement composition, because it shows excellent flame retardant properties, it is suitable for marine structures compared to the conventional cement composition. In particular, when compared with mixed cements, which are generally known to be excellent for marine structures, they exhibit excellent flame resistance characteristics (chloride ion penetration resistance and diffusion characteristics) at early age, and also excellent flame resistance characteristics at long age.

In addition, in the case of marine structures, crack reduction is most important because deterioration proceeds rapidly due to the direct penetration of chloride ions during the occurrence of cracks.In the conventional cement composition, since the hydration structure of the concrete is dense as compared to conventional mixed cements, dry shrinkage cracking of concrete An excellent effect can also be expected in reduction.

However, according to the conventional flame retardant cement composition, the effect of flame retardation can be expected, but there is a problem that the algae is not slid because it does not create a habitat environment of algae.

The present invention is to solve the above problems, and to protect the marine structures such as artificial reefs and sofa blocks from salt damage, and to prevent corrosion and to reduce the carbon dioxide so that the roots of the underwater plants quickly stick and maintain the sticking for a long time. It is an object of the present invention to provide a marine structure composition comprising environmentally friendly artificial reefs and sofa blocks using flame retardant cement and marine structures including artificial reefs and sofa blocks produced by the composition.

Marine structure composition comprising an artificial reef and a sofa block according to the present invention for achieving the above object, usually 30 to 50% by weight cement, blast furnace slag 30 to 50% by weight, fly ash 10-30% by weight, Anhydrous gypsum 4-20% by weight, at least one of steelmaking slag or red mud is characterized in that 5 to 10% by weight is mixed.

According to the marine structure composition comprising environmentally friendly artificial reef and sofa block using flame retardant cement for carbon dioxide reduction according to the present invention and the marine structure comprising artificial reef and sofa block produced by the composition, the penetration of salt effectively Durability can be improved by minimizing the corrosion of reinforcing bars by salt, and preventing the elution of toxic alkaline compounds through iron and phosphorus and supplying nutrients so that the roots of seaweeds can stick to them quickly. It can improve the utility and reliability.

1 is a photograph of a sofa block of the marine structure according to the present invention.

Marine structure composition comprising environmentally friendly artificial reef and sofa block using flame retardant cement for carbon dioxide reduction according to the present invention, usually cement 30-50% by weight, blast furnace slag 30-50% by weight, fly ash 10-30% by weight 4 to 20% by weight of anhydrous gypsum, steel slag or red mud at least one of 5 to 10% by weight of the mixture is made.

In the marine structure composition according to the present invention, a cement hydrate is prepared by mixing a fine blast furnace slag powder having an initial latent rigidity and a fly ash for a long-term pozzolanic reaction as a starting material of one common portland cement as a starting material. It is to add anhydrous gypsum as a hydration accelerator of the improved and admixture. Although gypsum is added in the conventional cement composition, the reason is generally to delay the hardening of cement or to promote the hydraulic properties of the slag when the slag fine powder is contained. In this case, the amount of gypsum added is generally 4% or less.

The composition of the present invention has a composition in which a larger amount of gypsum is added compared to this general gypsum amount. Anhydrous gypsum added in excess of the existing composition promotes the formation of ettringite in the hydrate of cement, and the resulting large amount of ettringite fills the pores of the concrete, thereby preventing the penetration of chloride ions. Will improve. In addition, since the ethrinzite is produced in a large amount from the beginning of hydration, the resistance of chloride penetration at the early age, which is most problematic when using the existing slag, is greatly improved. In addition, when the produced ethrinzite reacts with C3A and the like in concrete, it produces monosulfate (Mosulfate) (C3A · CaSO4 · 12H2O) in hydrate, and the produced monosulfate reacts with chloride ions in seawater to form Friedel salt. (C3A.CaCl2.10H2O) is formed. This reaction consequently immobilizes the chloride ions in the salt, thus further improving the flame retardant properties of the concrete.

Therefore, the composition according to the present invention exhibits better penetration resistance than mixed cement such as blast furnace slag cement or tricomponent cement, which is known to have excellent seawater resistance, and at the early age, which is the biggest disadvantage of the mixed cement. Low penetration resistance can be greatly improved.

In the present invention, the starting material cement may be a conventional cement such as one ordinary portland cement suitable for KS L 5201, and the blast furnace slag is preferably a fine powder having a powder degree (specific surface area) of 4,000 to 6,000 cm 2 / g. In addition, the refined fly ash powder is preferably in the range of 3,000 ~ 5,000 cm2 / g and the loss on ignition is 5% or less, and dry gypsum is preferably in the range of 4,000 ~ 6,000 cm2 / g powder.

Hereinafter, each of the components constituting the composition of the present invention will be described in more detail the mechanism for improving the flame retardant properties of the concrete produced by the cement composition of the present invention. However, the mechanisms described throughout the specification of the present invention are provided to aid the understanding of the present invention based on the knowledge of the present inventors, and are provided in a limited sense that the effects of the present invention must be obtained in the mechanisms described below. It is not.

Among the constituents of cement, dihydrate gypsum (CaSO4 · 2H2O) added in the manufacture of cement or anhydrous gypsum (CaSO4) added separately is reacted with the components in the cement, in particular C3A (3CaO · Al2O3), so that the early In the AFt phase, C3A, 3CaSO4, 32H2O) is produced, and the amount of the produced ethrinzine decreases as the hydration proceeds or a part thereof is transferred to the mono sulfate (AFm phase, C3A, CaSO4, 12H2O). When a large amount of gypsum is added as in the present invention, ethrinzite is sufficiently produced from the beginning to densify the structure of the cement, thereby increasing penetration resistance to chloride ions in early age.

In addition, in the case of general cement, the produced ethrinzite is mainly present only at the beginning, but in the composition of the present invention, since a sufficient amount of gypsum is added, ethrinzite is also present in a part of the organs, or part of the ethrinzai The nets may be generated continuously. The ethrinzite thus produced densely fills the voids in the concrete structure, thereby increasing resistance to chloride penetration even at long-term age.

In addition, the blast furnace slag powder used in the composition is produced as a by-product in the steel mill, and the blast furnace slag powder has latent hydrophobic properties and thus has a hard curing property. When stimulated by alkaline or sulfate salts, the blast furnace slag itself causes a hydration reaction. In general, mineral admixtures such as blast furnace slag powder and fly ash have lower hydration reactivity compared to cement, which results in slow initial strength development.In the case of concrete substituted with these admixtures, the penetration resistance against chloride ions is known to be poor at early age. have. However, since the composition of the present invention adds a relatively large amount of anhydrous gypsum, the pores of the concrete are densely packed by sufficiently promoting the initial hydration of the blast furnace slag, resulting in increased strength as well as penetration resistance against chloride ions at an early age. Remarkably improved properties.

On the other hand, the ethrinzite produced by the reaction of cement or blast furnace slag fine powder is also converted to mono sulfate (AFm phase) when it reacts with C3A component again, and when the mono sulfate meets chloride, Friedel salt, an insoluble salt ( C3A.CaCl2.10H2O). Since the composition of the present invention can immobilize chloride ions penetrated into concrete through the generation of insoluble salts in concrete, chlorides in seawater can no longer penetrate and consequently improve the flame resistance of concrete. For the transformation of ethrinzite to mono sulfate, the C3A or Al2O3 content in concrete is an important variable. In the composition of the present invention, by using a combination of high-loss rag fine powder or fly ash, which has a much higher Al2O3 content than a general cement, it provides a better environment for the transition to mono sulfate and provides chloride ions penetrated into concrete. It promotes the formation of the Friedel salt, which is a reaction product of, and has an immobilization effect of chloride ions.

In the case of fly ash, SiO 3-2 or Al 2 O 4-2 eluted on its own causes secondary pozzolanic reactions over a long period with Ca (OH) 2, the primary hydrate of cement. The calcium silicate (CSH) and calcium aluminate (CAH) hydrates produced by this reaction have a denser hydration structure than Ca (OH) 2, which is a hydrate of cement itself, and has a capillary pore that is a major migration path of chloride ions. Because of its compact filling, it improves the penetration resistance against chloride ions at long-term age. Fly ash also densely fills the needle tissue of pre-generated ethrinzite, resulting in improved flame resistance of the concrete.

In order to take full advantage of the reaction mechanism and the sequence of reaction between cement and mineral admixtures, the composition added relatively large amount of anhydrous gypsum to these material combinations. As a result of this addition, ordinary portland cement as well as other high slag cement or ply It has excellent flame retardancy at early and long age which cannot be secured in mixed cement such as ash cement. On the other hand, gypsum addition over the range suggested by the composition of the present invention causes excessive generation of ethrinzite, but excessively produced ethrinzite may reduce the strength of the structure by expansion.

Another feature of the composition is that it has excellent characteristics in reducing cracking and hydrating heat generation. In the case of general marine structures, cracking is very important because degradation proceeds rapidly due to the direct penetration of chloride ions when cracks are generated. In the case of the composition of the present invention, concrete can be compared with cement and mixed cement. Since the hydration structure of denser is more dense, excellent effect can be expected to reduce the dry shrinkage cracking of concrete. In addition, since the present composition uses a mineral admixture having a low hydration calorific value, temperature cracking due to the rise of hydration heat is also very low. Considering the fact that the heat of hydration is a big problem because the concrete structure in the marine environment is mainly a mass structure, the composition proposed in the present invention can be expected to greatly reduce the temperature cracking effect, which is very suitable as a cement material for the concrete structure in the marine environment. Can be.

Steelmaking slag, which is well known, is generated during the process of refining pig iron in a converter to remove carbon, phosphorus, and sulfur as impurities, and has a large amount of iron (Fe), and less than 100 mesh is used.

Red mud refers to a by-product of a large amount of residue (insoluble bauxite containing a large amount of iron) after leaching of aluminum during the Bayer process of extracting aluminum hydroxide from bauxite, and can minimize the elution of heavy metals. .

Red mud has a particle size of 100 mesh or less. Because less than 100 mesh can satisfy the strength required for offshore structures.

Steelmaking slag and red mud may be used alone or in combination. This is because iron ions eluted from the large surface of artificial reefs are essential nutrients of phytoplankton, which provides a good environment for plant growth and, in turn, can increase the counterfeiting effect of fish.

When steelmaking slag and red mud are used alone, when the mixture of steelmaking slag and red mud is used, 5 to 10% by weight of both. This is because when mixed at 5 wt% or less, elution of toxic alkaline compounds such as calcium hydroxide cannot be prevented, and when mixed at 10 wt% or more, the effect does not change significantly.

In the present invention, the zeolite may be added to further supply the phosphorus component to the aquatic ecosystem to activate the propagation and root swelling of the aquatic plant.

The zeolite is a zeolite according to Patent No. 0070602 patented by the applicant.

Zeolite is manufactured through the following process, and detailed description thereof is omitted since it is shown in Patent No. 0702602.

A mixing step of mixing 100 parts by weight of any one selected from a treatment plant sludge, fly ash and waste silica of alum series, 10 to 14 parts by weight of phosphoric acid relative to the treatment, and 100 parts by weight of water relative to the treatment; Reacting the mixture by stirring for 1 to 3 hours through a stirrer, while maintaining a temperature of 100 ~ 120 ℃ and evaporating only the moisture of the mixture; A cooling step of cooling the reaction by stirring through a stirrer at room temperature for 1 to 3 hours when the reaction is completed; And when the cooling is complete consists of a drying step of obtaining a final product zeolite by drying in a drier under the maintained conditions of 110 ~ 140 ℃ so that the water contained in the reaction is completely evaporated.

Zeolite prepared in this manner may be added 3 to 7 parts by weight based on 100 parts by weight of the marine structure composition. When it is mixed below 3 parts by weight, the effect of nutrient supply is not exerted, and when it is mixed by 7 parts by weight or more, the oversupply of phosphorus may change the formation of marine structures. Care should be taken as this may provide a cause.

Zeolites elute phosphorus to replenish nutrients so that algae can take root quickly, and breeding of algae causes aquatic organisms such as abalone and conch to gather around, providing a spawning ground for fish to enhance the function of artificial reefs. have.

The marine structure composition according to the present invention is a raw material such as an artificial reef submerged in water, a sofa block exposed to the surface of the water, and, in the case of the sofa block, the color of concrete may be exposed as it is on the surface of the water so that pigment may be added.

The pigment may be used in powder (particle size is similar to other materials), liquid, red, green, blue, etc., and 3 to 10 parts by weight is mixed with 100 parts by weight of the marine structure composition. This is because when the mixture is mixed in an amount of 3 parts by weight or less, the color of the pigment cannot be expressed, and when mixed in an amount of 10 parts by weight or more, other colors may be expressed due to excessive addition.

<Examples>

1. Raw material formulation (unit kg)

division cement Blast furnace slag Fly ash Anhydrous gypsum Red mud Zeolite Pigment Remarks Example 1 35 35 15 5 10 Artificial reef Example 2 35 35 15 5 10 5 Artificial reef Example 3 35 35 15 5 10 - 3 Sofa block

In Examples 2 and 3, zeolite and pigment were added to the mixed amount of cement, blast furnace slag, fly ash, anhydrous gypsum and red mud.

division
(mg / L) Heavy Metal Dissolution Test Iron Phosphorus ingredient Remarks Cu CD Pb Cr ^{6 +} Example 1 0.001 ND ND ND 75 - Artificial reef Example 2 0.001 ND 0.001 ND 72 2.2 Artificial reef Example 3 ND ND ND ND - - Sofa block
(See Fig. 1)

Claims (4)

delete Reduction of carbon dioxide by mixing 30 ~ 50% by weight of cement, 30 ~ 50% by weight of blast furnace slag, 10 ~ 30% by weight of fly ash, 4 ~ 20% by weight of anhydrous gypsum, at least 5-10% by weight of steelmaking slag or red mud As an offshore structure composition comprising an eco-friendly artificial reef and a sofa block using flame retardant cement for
With respect to 100 parts by weight of the marine structure composition comprising an environmentally friendly artificial reef and sofa block using flame retardant cement for carbon dioxide reduction,
A mixing step of mixing 100 parts by weight of any one selected from a treatment plant sludge, fly ash and waste silica of alum series, 10 to 14 parts by weight of phosphoric acid relative to the treatment, and 100 parts by weight of water relative to the treatment; Reacting the mixture by stirring for 1 to 3 hours through a stirrer, while maintaining a temperature of 100 ~ 120 ℃ and evaporating only the moisture of the mixture; A cooling step of cooling the reaction by stirring through a stirrer at room temperature for 1 to 3 hours when the reaction is completed; And 3 to 7 parts by weight of the zeolite prepared through a drying step of drying in a drier at 110 to 140 ° C. in order to completely evaporate the moisture contained in the reactant when cooling is completed. Marine structure composition comprising environmentally friendly artificial reef and sofa block using flame retardant cement for.
The marine structure composition according to claim 2, wherein environmentally friendly artificial reef and sofa blocks using flame retardant cement for carbon dioxide reduction are formed by mixing 3 to 10 parts by weight of powder pigment with respect to 100 parts by weight of the marine structure composition.
A marine structure comprising an eco-friendly artificial reef and sofa block using flame retardant cement for carbon dioxide reduction, characterized in that the composition according to claim 2 or 3 as a material.

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