KR101801966B1 - A Solidification Agent Comprising Acid-Treated Waste Oyster Shell And Construction Method Using The Same - Google Patents

Abstract

The present invention relates to a fire extinguisher containing sulfuric acid-treated oyster shells, and it is possible to use a natural oyster shell which is difficult to treat, and a coal fly ash which has not been recycled, While contributing to environmental preservation, it does not use expensive raw materials such as cement, and provides high strength fire.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a solidification agent containing a sulfated oyster shell,

The present invention relates to a fire extinguisher containing a sulfuric acid treated oyster shell, and more particularly, to a fire extinguisher containing a sulfuric acid treated oyster shell, and more particularly, to a fire extinguisher containing waste oyster shell by treating the waste oyster shell with a sulfuric acid solution not consuming high energy consuming high energy, And a construction method using the same.

Cement is the most important and widely used structural material for construction in the process of modernization of industry, and it is the basic material for construction of various social overhead capital such as roads, bridges, tunnels, harbors, houses and buildings. These cements are produced at the high temperature (about 1,500 ° C) during the firing process, that is, in the production of clinker, using limestone as the main raw material. In this process, carbon dioxide gas of 0.7 ~ 1.0 ton is produced per one ton of cement. Thus, although cement has played an important role in the construction industry in recent years, it has recently become increasingly recognized as a negative material for natural and global environment.

These cement production amounts to about 63 million tons per year in Korea alone, and it is the second highest carbon dioxide emission after China. Various efforts have been made to solve these problems and to improve the efficiency of the facilities to reduce the amount of carbon dioxide generated, to use alternative fuels instead of bituminous coal, to use mixed cement such as fly ash and blast furnace slag, or to develop materials to replace cement It is being tried.

As a substitute for such a cement, it is well known that the oyster shell, which is a by-product of the oyster aquaculture, is fired and mixed with fly ash, gypsum and slag, There is a variety of problems such as high energy consumption, extra processing cost, and excessive carbon dioxide generation (Patent Document 1).

Patent Document 1. Korean Patent Publication No. 2002-0093204

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a method of manufacturing a waste ointment which is capable of reducing production costs by using natural oyster waste as a waste without using cement, And provide a fire that can be secured.

The present invention has been made in view of the above-mentioned problems, and another object of the present invention is to provide a construction method using the fire.

In order to accomplish the above object, the present invention relates to a method for producing an oyster shell, comprising: (a) 30 to 50 wt% sulfuric acid treated oyster shell; (b) 5 to 30% by weight of any one selected from the group consisting of clay, coal ash, and mixtures thereof; And (c) 30 to 40 weight percent sodium hydroxide solution.

The sulfated oyster shell has a CaO content of 40 to 70 wt%, an SO ₃ content of 10 to 50 wt%, an Na ₂ O content of 0 to 10 wt%, a SiO ₂ content of 2 to 3 wt% and an MgO content of 0 to 10 wt% Characterized by containing a chemical component.

The oyster treated oyster shell is characterized in that the natural oyster shell is treated with a sulfuric acid solution having a concentration of 1 to 10 N.

The sodium hydroxide solution is characterized by a concentration of 1 to 10 N.

To achieve these and other objects, the present invention provides a method for producing oyster shells comprising the steps of: i) treating a natural oyster shell with a sulfuric acid solution to prepare a sulfuric acid treated oyster shell; (II) mixing the oyster treated oyster shell of step (I) with any one selected from the group consisting of loess, fly ash, and a mixture thereof, and sodium hydroxide solution to produce a solid fire; And III) implanting and curing a fire in the step II), wherein in the step II), the fire extinguisher comprises 30 to 50 wt% of a sulfuric acid treated oyster shell; 5 to 30% by weight of any one selected from the group consisting of clay, coal ash, and mixtures thereof; And 30 to 40% by weight of a sodium hydroxide solution.

The Ⅲ) step is characterized in that for producing the first to the curing at 50 ℃ 10 to 30 days, 3.9 ㎏ _f / ㎠, up to 55 ㎏ _f / ㎠ the compressive strength is maintained up to high fire.

According to the present invention, it is possible to use natural oyster shell which is difficult to process and coal fly ash which has not been recycled but has been buried in a fire with high economic and performance properties, thereby contributing to environment conservation by treating waste in large quantity, A high-strength fire is provided without using the raw material.

In addition, since the cement can be completely replaced by the oyster treated oyster shell of the present invention and the fires including the loess, fly ash, or a mixture thereof and sodium hydroxide, the generation of a large amount of carbon dioxide, which is generated during the production of the cement, Natural oyster shells and coal ash are recycled, so the environmental burden as well as the economic burden for securing landfill can be solved.

FIG. 1A is a photograph of a specimen completed through 20 days of curing process after being manufactured from a cigarette of Example 8, FIG. 1B is a photograph of a specimen completed through a curing process of 20 days manufactured from the cigarette of Example 9 to be.
2 is a process diagram showing a method for constructing a fire according to the present invention.

Hereinafter, various aspects and various embodiments of the present invention will be described in more detail.

One aspect of the present invention is

(a) 30 to 50% by weight of the oyster treated oyster shell;

(b) 5 to 30% by weight of any one selected from the group consisting of clay, coal ash, and mixtures thereof; And

(c) 30 to 40% by weight of a sodium hydroxide solution, which can replace conventional cement.

In particular, the natural oyster shell used in the present invention accounts for about 300,000 tons of oyster cultivation industry each year, which is dominated by exports, the domestic market and the southern coastal economy. Of these, about 150,000 tons are not recycled, have. In order to solve this problem, the technology has been developed to be recycled as fertilizer and oyster seedlings. However, it has considerable problems in terms of quantitative limit of recycling, expensive facility investment, complicated process, high energy input and reclamation of landfill. Therefore, it is urgent to present a new low - cost solution for mass processing of natural oyster shells.

Accordingly, the present invention relates to a method of mixing natural oyster waste, which is a waste, with any one of yellow loess, fly ash, and a mixture thereof at a proper ratio through a simple acid treatment process without performing a high temperature baking process or purification process requiring high energy, Which are the technical characteristics of the system.

According to an embodiment of the present invention, the mixed content of the hull is selected from the group consisting of (a) an oyster treated oyster shell, (b) a dry mixed solid in which yellow loam, fly ash, Sodium hydroxide solution is added to ensure fluidity required for casting and to react with fodder required for solidification. Water may be further added depending on the viscosity of the harsh fire. However, when the excess amount of water is added at this time, the strength is reduced rather than the amount. Therefore, it is important to add an appropriate amount depending on the intended use.

The grafts treated with sulfuric acid, yellow loess and fly ash are all preferably in the range of 10 to 150 mu m, preferably 10 to 120 mu m, and their particle shape is preferably spherical. When these conditions are satisfied, And the frictional force is reduced and the fluidity can be increased.

(A) The oyster-treated oyster shell was prepared by treating natural oyster shell with sulfuric acid solution. The CaCO _{3, which} is the main component of the natural oyster shell, was converted into CaSO ₄ through the treatment with sulfuric acid as shown in the following chemical reaction formula 1, To produce a sulfuric acid treated oyster shell.

[Chemical reaction formula 1]

CaCO ₃ (S) + H ₂ SO ₄ (aq) → CaSO ₄ (S) + H ₂ O (aq) + CO ₂ ↑

Specifically, the concentration of the sulfuric acid solution used for acid treatment of the natural oyster shell may be 1 to 10 N (normal concentration), and preferably 5 to 10 N.

The concentration of the sulfuric acid solution may be 1 to 10 N, preferably 5 to 10 N. As the concentration of sulfuric acid increases from 1 N to 10 N, the conversion of CaCO ₃ to CaSO ₄ is increased Can be confirmed through an experimental example to be described later. However, when the concentration of the sulfuric acid solution is 10 N or higher, the conversion rate becomes gentle, so that the preferable concentration of the acid solution is 1 to 10 N.

Most preferably, the concentration of the sulfuric acid solution may be between 5 and 10 N, since 1 N is present at a ratio of about 7: 1 of the chemical composition of SO ₃ rather than the chemical composition of CaO, thus ensuring a sufficient amount of CaSO ₄ And by-products such as Na ₂ O are present. As will be described later in the experimental example, when the oyster shell treated with 1 N sulfuric acid is mixed with coal fly ash, the oyster shell treated with 10 N sulfuric acid solution is about four times lower than that prepared by mixing fly ash with coal fly ash.

However, the sulfuric acid-treated oyster treated with sulfuric acid solution at a concentration of 5 to 10 N can be appropriately selected depending on the application site. The oyster shell treated with sulfuric acid solution of 5 to 7 N has a chemical composition of SO ₃ This is about 6: 3, and there is no chemical component of MgO that affects the long-term expansibility that can prevent the cracking by shrinkage. However, the initial strength is weak with 10 N sulfuric acid solution It is advantageous that the treated oyster shell is about twice as much as the specimen prepared by mixing with fly ash.

On the other hand, the oyster shell treated with 8 to 10 N sulfuric acid solution has a chemical composition ratio of CaO and SO ₃ of 1: 1 and MgO chemical composition of 5 to 10% by weight even when there is no by-product such as Na ₂ O And the initial strength is relatively lower than that of the specimens prepared by mixing the oyster shell treated with the sulfuric acid solution of 5 to 7 N with the fly ash, but the long-term extensibility can be ensured.

In particular, the chemical components measured by the XRF analysis of the oyster shell treated with the 1 to 10 N sulfuric acid solution are 40 to 70% by weight of CaO, 10 to 50% by weight of SO ₃ , 0 to 10% by weight of Na ₂ O, An SiO ₂ content of 2 to 3% by weight and an MgO content of 0 to 10% by weight, and preferably an X-ray analysis of the oyster shell treated with the sulfuric acid solution having the concentration of 5 to 10 N, To 65 wt%, an SO ₃ content of 30 to 50 wt%, an Na ₂ O content of 0 wt%, a SiO ₂ content of 2 to 3 wt% and an MgO content of 0 to 10 wt% It should be used that is 3.5 ㎏ _f / ㎠, up to 50 ㎏ _f / in order to meet the ㎠ range or more, yet CaO content of 40 to 65% by weight, SO ₃ content of 30 to 50% by weight by-products such as Na ₂ O is not present.

In general, since natural oyster shells are made of CaCO ₃ as a main component, they must be converted to CaO through firing at a high temperature of 800 to 1200 ° C. for a long period of time, and they are consumed at high energy, Environmental and economic problems.

Therefore, in the present invention, in order to overcome such a problem and overcome this problem, the existing high temperature firing process is replaced with the sulfuric acid treatment process in order to process the natural oyster shell, thereby significantly reducing the process cost through energy saving.

In general, fly ash is coal ash discharged from a combustion boiler at 1400 ℃ in a combustion boiler such as a thermal power plant that uses pulverized coal as fuel, and 60 million tons of coal ash generated annually is recycled as cement material. % Are landfilled, so continuous research and development is necessary.

Researches have been conducted to develop a method for mass-treating waste oyster shells and coal ash causing such environmental pollution problems. However, as described above, in order to consume large amount of natural oyster shell as a civil engineering material, 1200 < 0 > C), it requires high energy cost and massive factory construction cost. However, the present invention saves much of the energy cost.

According to one embodiment of the present invention, when the above-mentioned (c) sodium hydroxide solution is added to the dried mixed solids in which (a) the oyster treated oyster shell and (b) the ocher, the fly ash, As shown in the following chemical reaction formula 2, the sulfuric acid-treated oyster shell reacts with the sodium hydroxide solution to produce hydrated lime. Then silica (SiO ₂ ) or alumina (Al ₂ O ₃ ) provided from the coal fly ash or the alumina It forms a solid cargo through the reaction.

[Chemical reaction formula 2]

(Aq) Ca ₂ SO ₄ (ag) + Ca (OH) ₂ (aq) CaSO ₄ (S) + ₂ NaOH

[Chemical reaction formula 3]

_{3Ca (OH) 2 + 2SiO 2} → 3CaO · 2SiO 2 · 3H 2 O

[Chemical reaction formula 4]

_{3Ca (OH) 2 + Al 2} O 3 → 3CaO · Al 2 O 3 · 3H 2 O

The solubility of silica, alumina, or the like solves the solidification reaction that generates the insoluble compound, that is, solid matter, by the reaction of the chemical reaction equations 3 and 4 in which the chemical reaction formula ₂ is solidified with Ca (OH) ₂ generated from the sulfuric acid- It is called the reaction.

Such a fire can be obtained by the physical and chemical reactions such as exhibiting sufficient compressive strength through the solidification phenomenon caused by the foil reaction, and even if the waste oyster shell, loess or fly ash or a mixture thereof is used, can do.

(B) loess, fly ash, and mixtures thereof. Preferably, only fly ash is added, only loess is added, or a mixture of fly ash and loess can be added, more preferably, Only yellow soil is added. Because the compressive strength of the final finished specimens according ocher inducing Four jeulran response to the input tray to supply a sufficient amount of silica and alumina because it can achieve more than 50 ㎏ _f / ㎠.

In order to achieve the compressive strength of the final finished specimens over 10 ㎏ _f / ㎠ (a) a sulfuric acid treated oyster shell 40 to 50% by weight; And (b) 10 to 30% by weight of any one selected from the group consisting of clay, coal ash, and mixtures thereof; And (c) 30 to 40% by weight of a sodium hydroxide solution. If the (a) sulfuric acid when mixed with the treated oyster shell to less than 40% by weight, as well as the initial strength is generated a problem that long-term strength also decreases, when blended with more than 50% by weight of the main component of the sulfuric acid-treated oyster shell CaSO ₄ and fly ash Or the stoichiometric ratio between silica (SiO ₂ ) and alumina (Al ₂ O ₃ ) provided from the loess is inadequate, so that there is a problem that the compressive strength is significantly lowered.

If (b) any one selected from the group consisting of clay, coal ash and mixtures thereof is added in an amount of less than 10% by weight, there arises a problem that the initial strength is significantly lowered, and when it exceeds 30% by weight The content of the sulfuric acid-treated oyster shell is relatively decreased. Therefore, there is a possibility that the intensity manifestation greatly varies depending on the kind of the target soil.

If the sodium hydroxide solution (c) is added in an amount of less than 30% by weight, the reaction rate with the sulfuric acid-treated oyster shell may decrease and the solution may not be uniformly solidified. And the excessive sodium ion impairs the reaction of the phosgene. Therefore, the compressive strength of the fire may be lowered, or the period of time required for curing may be excessively long.

In other words, the fireproofing according to the present invention comprises: (a) 40 to 50% by weight sulfurized oyster shell; And (b) 10 to 30% by weight of loess; And (c) 30 to 40% by weight solution of sodium hydroxide; together is most desirable to mix in is because to obtain the most superior than 50 ㎏ _f / ㎠ compressive strength.

As will be described later in the Experimental Example, the sodium hydroxide solution (c) can be used at a concentration of 1 to 20 N in the solidification according to the present invention, and preferably, a specimen prepared by treating a 1 N sodium hydroxide solution with a compressive strength It is preferable to use a 5 to 15 N sodium hydroxide solution which is 11 to 15 times better than the sodium hydroxide solution. If sodium hydroxide solution is used at a concentration exceeding 20 N, excess sodium ions inhibit the reaction of the phosgene, so that the compression strength of the final finished specimen may be lowered, or the period of time required for curing may become excessively long May occur.

The high fire When drilling recovered to backfill material, and the compressive strength in the 1 to 50 ℃, when cured for about 10 to 30 days to at least 3.9 ㎏ _f / ㎠, up to 55 ㎏ _f / ㎠ to determine maintained, compaction process It is advantageous in that it can be constructed by the non-compacting method.

Another aspect of the present invention relates to a method for constructing a fire comprising the steps of:

(I) treating the natural oyster shell with a sulfuric acid solution to prepare a sulfuric acid treated oyster shell;

(II) mixing the oyster treated oyster shell of step (I) with any one selected from the group consisting of loess, fly ash, and a mixture thereof, and sodium hydroxide solution to produce a fire; And

And (III) placing and curing the fire in step (II).

The components of the fire produced through the above three steps can be classified into main ingredients and sub-materials. The main ingredients are oyster shells treated with sulfuric acid; And any one selected from the group consisting of loess, fly ash, and mixtures thereof, and the sub ingredient includes a sodium hydroxide solution.

The fire can be used as a backfill material for various architectural and civil engineering works and as a substitute for cement. In addition, it can be used as a substitute for cement used for early repayment of road construction, road repellent, and various restoration works.

FIG. 2 is a process diagram illustrating a method for constructing a fire in accordance with the present invention, and will be described in detail below with reference to FIG.

First, I) treating a natural oyster shell with a sulfuric acid solution to produce an oyster shell treated with sulfuric acid. Specifically, the natural oyster shell refers to an oyster shell without any treatment.

Before the natural oyster shell is treated with sulfuric acid, the natural oyster shell is washed and dried, and then pulverized to have a particle size ranging from 10 to 150 mu m to ensure intermolecular fluidity (Fig. 2, washing and crushing the natural oyster shell) .

The pulverized oyster shell powder can be treated with a sulfuric acid solution.

Through the process of treating the natural oyster shell with a sulfuric acid solution, CaCO _{3, which} is the main component of the natural oyster shell, is converted into CaSO ₄ through the treatment with sulfuric acid as shown in the following chemical reaction formula 1, and a sulfuric acid- (Fig. 2, I) step of producing the oyster treated oyster shell).

[Chemical reaction formula 1]

CaCO ₃ (S) + H ₂ SO ₄ (aq) → CaSO ₄ (S) + H ₂ O (aq) + CO ₂ ↑

The concentration of the sulfuric acid solution may be 1 to 10 N, preferably 5 to 10 N. As the concentration of sulfuric acid increases from 1 N to 10 N, the conversion of CaCO ₃ to CaSO ₄ is increased Can be confirmed through an experimental example to be described later. However, when the concentration of the sulfuric acid solution is 10 N or more, the conversion rate is gentle, and therefore, the preferable concentration of the sulfuric acid solution is 1 to 10 N.

Most preferably, the concentration of the sulfuric acid solution may be between 5 and 10 N, since 1 N is present at a ratio of about 7: 1 of the chemical composition of SO ₃ rather than the chemical composition of CaO, thus ensuring a sufficient amount of CaSO ₄ And by-products such as Na ₂ O are present. As will be described later in the experimental example, when the oyster shell treated with 1 N sulfuric acid is mixed with coal fly ash, the oyster shell treated with 10 N sulfuric acid solution is about four times lower than that prepared by mixing fly ash with coal fly ash.

However, the sulfuric acid-treated oyster treated with sulfuric acid solution at a concentration of 5 to 10 N can be appropriately selected depending on the application site. The oyster shell treated with sulfuric acid solution of 5 to 7 N has a chemical composition of SO ₃ This is about 6: 3, and there is no chemical component of MgO that affects the long-term expansibility that can prevent the cracking by shrinkage. However, the initial strength is weak with 10 N sulfuric acid solution It is advantageous that the treated oyster shell is about twice as much as the specimen prepared by mixing with fly ash.

On the other hand, the oyster shell treated with 8 to 10 N sulfuric acid solution has a chemical composition ratio of CaO and SO ₃ of 1: 1 and MgO chemical composition of 5 to 10% by weight even when there is no by-product such as Na ₂ O And the initial strength is relatively lower than that of the specimens prepared by mixing the oyster shell treated with the sulfuric acid solution of 5 to 7 N with the fly ash, but the long-term extensibility can be ensured.

Oyster shells treated at a high temperature of 800 to 1200 DEG C for a long period of time have environmental and economical problems such as high energy consumption in the manufacturing process and excessive carbon dioxide emission. In the present invention, in order to overcome such a problem and to overcome this problem, the present invention is economically efficient because the natural oyster shell is treated with an acid treatment process to lower the process cost and generate low energy as described above.

Thereafter, (II) a sulphate-treated oyster shell of the above step (I) and any one selected from the group consisting of loess, fly ash, and a mixture thereof and a sodium hydroxide solution are mixed to produce a fire (FIG. 2, Manufacturing step). Specifically, when the sodium hydroxide solution is added to the dry mixed solids in which the oyster-treated oyster shell, yellow loam, fly ash, or a mixture thereof is mixed, the sulfated oyster treated with sodium hydroxide solution reacts with the sodium hydroxide solution Hydrated lime is formed and solidified by the fosilan reaction of the chemical reaction formulas 3 and 4 of silica (SiO ₂ ) and alumina (Al ₂ O ₃ ) provided from the fly ash or loess.

[Chemical reaction formula 2]

(Aq) Ca ₂ SO ₄ (ag) + Ca (OH) ₂ (aq) CaSO ₄ (S) + ₂ NaOH

[Chemical reaction formula 3]

_{3Ca (OH) 2 + 2SiO 2} → 3CaO · 2SiO 2 · 3H 2 O

[Chemical reaction formula 4]

_{3Ca (OH) 2 + Al 2} O 3 → 3CaO · Al 2 O 3 · 3H 2 O

Before step (II), any one selected from the group consisting of loess, fly ash, and mixtures thereof is washed and dried, and thereafter pulverized to have a particle size of 10 to 150 μm, preferably 10 to 120 μm (FIG. 2, washing and crushing loess or fly ash or a mixture thereof).

It may be any one selected from the group consisting of loess, coal fly ash, and mixtures thereof. Preferably, only fly ash is added, only yellow loam is added, or a mixture of fly ash and loess can be added, . Because the compressive strength of the final finished specimens according ocher inducing Four jeulran response to the input tray to supply a sufficient amount of silica and alumina because it can achieve more than 50 ㎏ _f / ㎠.

In addition to the final compressive strength of the finished specimen to achieve more than 10 ㎏ _f / ㎠ the sulfate process oyster shell 40 to 50% by weight; And 10 to 30 wt.% Of any one selected from the group consisting of clay, coal ash, and mixtures thereof; And 30 to 40% by weight of a sodium hydroxide solution.

If the sulfuric acid treated oyster shell is blended at less than 40 wt%, the initial strength as well as the long-term strength are lowered. If the oyster shell is added in an amount exceeding 50 wt%, oxalic acid-treated oyster shell, CaSO ₄ , Or the ratio of silica (SiO ₂ ) and alumina (Al ₂ O ₃ ) provided from the loess is not matched, so that there is a problem that the compressive strength is significantly lowered.

If the content of any one selected from the group consisting of clay, coal ash and mixtures thereof is less than 10% by weight, there is a problem that the initial strength is significantly lowered. When the content exceeds 30% by weight, Since the content of sulfuric acid treated oyster shells is relatively reduced, there is a possibility that the intensity manifestation fluctuates greatly depending on the kind of the target soil.

If the sodium hydroxide solution is added in an amount of less than 30% by weight, the rate of reaction with the sulfuric acid-treated oyster shell may decrease, resulting in a problem of not being solidified uniformly. If the sodium hydroxide solution is added in an amount exceeding 40% by weight, And the excessive sodium ion is present to inhibit the phosgene reaction, so that the compressive strength may be lowered, or the period required for curing may be excessively long.

In other words, the fireproofing according to the present invention comprises 40 to 50% by weight of the sulfuric acid treated oyster shell; And 10 to 30% by weight of loess; And a solution of sodium hydroxide of 30 to 40% by weight; together is most desirable to mix in is because to obtain the most superior than 50 ㎏ _f / ㎠ compressive strength.

As will be described later in the Experimental Example, the sodium hydroxide solution concentration can be used in the range of 1 to 20 N in the fire according to the present invention, and preferably the compression strength is eleven times greater than the specimen prepared by treating with 1 N sodium hydroxide solution To 15 times better, 5 to 15 N sodium hydroxide solution is preferably used. If sodium hydroxide solution at a concentration exceeding 20 N is used, the excessive sodium ion impairs the fosilan reaction. Therefore, the compression strength of the final finished specimen is lowered and the period of time required for curing is excessively long Problems can arise.

Finally, Ⅲ) Putting and curing the fire in Ⅱ). After the user placing a solidifying prepared in Ⅱ) step, 1 to 50 ℃, a compressive strength to determine the retained when cured for about 10 to 30 days to at least 3.9 ㎏ _f / ㎠, up to 55 ㎏ _f / ㎠.

Also, in the high-fire construction method of the present invention, it is possible to use a port (storage facility, storage facility, etc.) Or a continuous vortex type mixer, or using a stationary mixer for batchwise solidification processing.

FIG. 1A is a photograph of a specimen completed through a 20-day curing process manufactured from the fire in Example 8, FIG. 1B is a photograph of a specimen completed through a 20-day curing process manufactured from a fire in Example 9, It can be seen that all of the specimens prepared from the two examples (Examples 8 and 9) are maintained at high strength without cracking.

Hereinafter, the present invention will be described in more detail with reference to Examples and the like, but the scope and content of the present invention can not be construed to be limited or limited by the following Examples. 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 and scope of the present invention as set forth in the following claims. It is natural that it belongs to the claims.

In addition, the experimental results presented below only show representative experimental results of the embodiments and the comparative examples, and the respective effects of various embodiments of the present invention which are not explicitly described below will be specifically described in the corresponding part.

Manufacturing example  1 to 3. Sulfuric acid-treated Oyster shell

The natural oyster shells were obtained from Haegang, Gyeongnam, Tongyoung, and dried at 90 ℃. The natural oyster shells were pulverized and passed through 125 mesh or less to prepare natural oyster shell powder. 600 g of the natural oyster shell powder and 900 g of 1 to 10 N sulfuric acid were mixed and reacted for 12 hours, and then recovered through filtration. The resulting oyster shell was dried at 90 ° C to prepare oyster powder treated with sulfuric acid.

The specific mixing ratio and the weight of the finally obtained sulfuric acid-treated oyster shell powder are summarized in Table 1.

Sulfuric acid solution concentration (N) The weight (g) of the finally obtained sulfuric acid treated oyster shell powder Production Example 1 One 566 Production Example 2 5 619 Production Example 3 10 715

As shown in Table 1, represent the difference in handling of sulfuric acid before and after natural oyster shell weight, which as by treatment of the natural oyster shell with sulfuric acid, the CaCO which was a main component of the natural oyster shell ₃ as shown in chemical equation 1, converted into CaSO _4, it Which means that the oyster-treated oyster shell as the main component is being produced.

[Chemical reaction formula 1]

CaCO ₃ (S) + H ₂ SO ₄ (aq) → CaSO ₄ (S) + H ₂ O (aq) + CO ₂ ↑

Manufacturing example  4. Coal fly ash (coal ash)

The coal ash collected at the fly ash landfill site of the thermal power plant in Samchonpo, Kyungnam Province was dried at 90 ℃ for 12 hours and passed through 125 mesh to select.

Manufacturing example  5. Yellow soil

Clay was collected from Kyungnam Sancheong, dried at 90 ℃ for 12 hours and passed through 125 mesh.

Example  1 to 13. Only in the fire  Manufactured Specification  Produce.

The oyster treated oyster shell prepared in Preparation Examples 1 to 3, the fly ash prepared in Preparation Example 4 and the yellow loess prepared in Preparation Example 5 were added to the sodium hydroxide solution, stirred using a high speed stirrer, A cylindrical specimen with a diameter of 5 ㎝ and a surface area of 19.6 ㎠ was prepared by curing in a water bath for 20 days.

At this time, the mixing weight percent of the fly ash, the oyster treated with sulfuric acid, the yellow soil and the sodium hydroxide is shown in Table 2 below.

Sulfuric acid oyster shell Coal fly ash
(weight%) ocher
(weight%) Sodium hydroxide solution sample weight% Concentration (N) weight% Example 1 Production Example 1 31 31 - One 38 Example 2 Production Example 1 31 31 - 10 38 Example 3 Production Example 2 31 31 - One 38 Example 4 Production Example 2 31 31 - 5 38 Example 5 Production Example 2 31 31 - 10 38 Example 6 Production Example 2 31 31 - 15 38 Example 7 Production Example 2 15 47 - 15 38 Example 8 Production Example 2 47 15 - 15 38 Example 9 Production Example 2 47 - 15 15 38 Example 10 Production Example 2 47 7.5 7.5 15 38 Example 11 Production Example 2 31 31 - 20 38 Example 12 Production Example 3 31 31 - One 38 Example 13 Production Example 3 31 31 - 10 38

Experimental Example  1. Sulfuric acid treated Oyster  Component analysis

In order to confirm the conversion and chemical composition change of the oyster treated oyster shell according to the concentration of the sulfuric acid solution, the components of the oyster treated oyster shells prepared in Production Examples 1 to 3 and the natural oyster shells not subjected to any treatment were subjected to XRF analysis, Respectively. The results are shown in Table 3 below.

Chemical composition analysis of sulfuric acid treated oyster shell (% by weight) ingredient Production Example 1 Production Example 2 Production Example 3 Natural oyster shell CaO 72.9 62.1 45.5 75.7 SO ₃ 10.1 31.4 41.5 0.8 Na ₂ O 7.8 - - 13.3 SiO ₂ 2.7 2.4 2.3 3.1 MgO 3.1 - 6.2 2.5

According to the results of Table 3, analysis of the chemical composition, the increase in SO ₃ is because it indicates that the SO ₃ group is bonded to CaO as a main component was the CaCO ₃ in the natural oyster shell converted into CaSO _4, the concentration of sulfuric acid at 1 N 10 N , The conversion of CaCO ₃ to CaSO ₄ is increased. However, when the concentration of the sulfuric acid solution is 10 N or more, it is found that the conversion rate is gentle, so that the preferable concentration of the sulfuric acid solution is 1 to 10 N.

Most preferably, the concentration of the sulfuric acid solution may be between 5 and 10 N, since 1 N is present at a ratio of about 7: 1 of the chemical composition of SO ₃ rather than the chemical composition of CaO, thus ensuring a sufficient amount of CaSO ₄ And by-products such as Na ₂ O are present. As will be described later, when an oyster shell treated with a 1 N sulfuric acid solution (Preparation Example 1) is mixed with coal fly ash to prepare a specimen, an oyster shell treated with a 10 N sulfuric acid solution (Preparation Example 3) Which is about four times lower than that of

However, from 5 to 10 in the oyster shell treated with a sulfuric acid solution of the N concentration may be properly selected in accordance with Where Used 5 to 7 the oyster shell treated with a sulfuric acid solution of the N concentration (Preparation 2) SO more chemical components of CaO ₃ The chemical composition is present at a ratio of about 6: 3, and the long-term expansibility is weak due to the absence of the chemical component of MgO which affects the long-term expandability which can prevent the decomposition by shrinkage. However, The oyster shell treated with sulfuric acid solution (Preparation Example 3) is twice as excellent as the specimen prepared by mixing with fly ash.

The 8 to 10 N with oyster shell treated with a sulfuric acid solution having a concentration of (Production Example 3) by-product is even CaO and the first chemical composition ratio of SO ₃ is not present, such as Na ₂ O: exists as a 1, MgO chemical ingredients 5 To 10% by weight, and the initial strength is relatively lower than that of the specimen prepared by mixing the oyster shell treated with the sulfuric acid solution having the concentration of 5 to 7 N and the fly ash, but the long-term expansibility can be ensured.

Experimental Example  2. Only in the fire  Manufactured Specimen  Comparison of compressive strength (1)

The compressive strengths of the specimens prepared from Examples 6 to 10 are shown in Table 4 below.

The compressive strength test was carried out using the uniaxial compressive strength standard test method (the rate of deformation was 1.0 mm / min (min) per minute) using a compressive strength test analyzer (300 KN-LVDT 1000 mm, Donga, Busan, Korea) ≪ / RTI >

Initial compressive strength
(㎏ _f / ㎠) Example 6 9.3 ± 0.5 Example 7 1.5 ± 0.5 Example 8 13.0 ± 1.2 Example 9 53.3 ± 1.3 Example 10 12.3 ± 2.7

As shown in Table 4, Examples 6 to 10 uniaxial compare the compressive strength of the specimens When, in the case to prepare a specimen of only smoke, ash, or contain only loess or ocher and coal ash is be added at the same time more than 10 ㎏ _f / ㎠ excellent or it represents the intensity, if only the yellow soil addition were identified prepared a specimen having at least 50 ㎏ _f / ㎠ remarkably excellent strength.

1 is a photograph of the specimen completed through the 20 days curing process of the fireproof fabric manufactured from Examples 8 and 9, FIG. 1A is a photograph of Example 8, FIG. 1B is a photograph of Example 9 . It can be seen from FIG. 1 that all of the specimens manufactured from the two embodiments (Examples 8 and 9) are maintained at high strength without cracking.

Experimental Example  3. Only in the fire  Manufactured Specimen  Comparison of compressive strength (2)

In order to confirm the influence of the concentration or mixing ratio of the sodium hydroxide solution on the compressive strength, the compressive strengths of the specimens prepared from Examples 1 to 6 and 11 to 13 are shown in Table 5 below Specifically, Table 5 relatively shows the compressive strengths of the specimens of Examples 2-6 and 11-13 based on the compressive strength of the specimens of Example 1.

The compressive strength test was carried out using the uniaxial compressive strength standard test method (the rate of deformation was 1.0 mm / min (min) per minute) using a compressive strength test analyzer (300 KN-LVDT 1000 mm, Donga, Busan, Korea) ≪ / RTI >

Relative compressive strength
(Based on Example 1) Example 1 One Example 2 6 Example 3 2 Example 4 8 Example 5 11 Example 6 15 Example 11 8 Example 12 4 Example 13 8

As shown in Table 5, when the compression strengths of Examples 1-6 and 11-13 were compared, it was found that the specimens prepared using sodium hydroxide solution having a concentration of 10 N and 15 N had the most compressive strength It was confirmed that 10 to 15 N sodium hydroxide solution was the most preferable.

Among them, however, it was confirmed that, as in Examples 5 and 6, when the oyster treated with oily acid was treated with sulfuric acid concentration of 5 to 10 N, it had a strength of 11 to 15 times better than that of Example 1.

That is, when only the sodium hydroxide solution is adjusted to 10 to 15 N, only the strength of 6-8 times higher than that of Example 1 can be obtained. However, if the concentration of the sodium hydroxide solution is controlled to 10 to 15 N simultaneously with the preparation conditions of the sulfuric acid- It can be seen that the strength is 11 to 15 times better than that of the first embodiment.

Claims (6)

(a) 30 to 50% by weight of the oyster treated oyster shell;
(b) 5 to 30% by weight of any one selected from the group consisting of clay, coal ash, and mixtures thereof; And
(c) 30 to 40% by weight of a sodium hydroxide solution,
The sulfated oyster shell has a CaO content of 40 to 70 wt%, an SO ₃ content of 10 to 50 wt%, an Na ₂ O content of 0 to 10 wt%, a SiO ₂ content of 2 to 3 wt% and an MgO content of 0 to 10 wt% Characterized in that it contains a chemical component. delete The method according to claim 1,
Wherein the sulfuric acid-treated oyster shell is produced by treating a natural oyster shell with a sulfuric acid solution having a concentration of 1 to 10 N. The method according to claim 1,
Wherein the sodium hydroxide solution has a concentration of 1 to 10 N. (I) treating the natural oyster shell with a sulfuric acid solution to prepare a sulfuric acid treated oyster shell;
(II) mixing the oyster treated oyster shell of step (I) with any one selected from the group consisting of loess, fly ash, and a mixture thereof, and sodium hydroxide solution to produce a fire; And
(III) placing and curing a fire in the step (II)
In the step (II), the hyaluronic acid may contain 30 to 50% by weight of a sulfurated oyster shell; 5 to 30% by weight of any one selected from the group consisting of clay, coal ash, and mixtures thereof; And 30 to 40% by weight of a sodium hydroxide solution;
The sulfated oyster shell has a CaO content of 40 to 70 wt%, an SO ₃ content of 10 to 50 wt%, an Na ₂ O content of 0 to 10 wt%, a SiO ₂ content of 2 to 3 wt% and an MgO content of 0 to 10 wt% A method for constructing a hot fire for a backfill, characterized by containing a chemical component. 6. The method of claim 5,
The Ⅲ) step is of from 1 to from 50 ℃ 10 to 30 days after curing and, 3.9 ㎏ _f / ㎠, backfill, characterized in that for producing a high fire which the compression strength is maintained up to 55 ㎏ _f / ㎠ damper and fire Construction method.

Images