WO2017122916A1 - Cement-free binder and application thereof - Google Patents

Abstract

The present invention relates to a cement-free binder and an application thereof. More specifically, the present invention provides an eco-friendly cement-free binder comprising fly ash, calcium oxide, and calcium chloride in a particular formulation, wherein the cement-free binder can be used and applied as mortar and concrete having low cost, high strength, light weight, and heavy metal adsorption and sound absorption performances, and thus can have great economic effects.

Description

Cement cement binder and its application

FIELD OF THE INVENTION The present invention relates to cementless binders and applications thereof, and more particularly, to a technique for preparing cementless binder compositions comprising fly ashes and chemically active agents and applying them to mortars and concrete.

As global warming has become a hot topic in recent years, carbon-based environmental policies have been implemented, and various efforts have been made to reduce carbon dioxide in the construction industry. Portland cement most widely used in the current construction industry as crushing mix of calcareous material and clay material in any ratio, and its manufacturing process massive emissions culprit of CO ₂ global warming while being recognized as negative materials about the natural environment have.

Accordingly, research has been conducted on low-carbon cementless binders to replace existing cement, and recently, various industrial by-products containing aluminosilicate minerals in Korea, Australia, USA, Japan, and Europe have been replaced by cement. Utilizing mortar and concrete is being developed. For example, an alkali activator is added to the blast furnace slag obtained by incineration of paper sludge generated as a by-product from a paper mill, or from blast furnace slag obtained by collecting impurities from iron ore in a blast furnace. Techniques, and the like are known (see Korean Patent Publication No. 10-1524298).

However, most cementless binder technologies do not reproduce the compressive strength of most Portland cements or require high manufacturing costs, or are difficult to handle with highly corrosive solutions exceeding 14, the highest pH. There was. In addition, although some fly ash has been introduced as an admixture of mortar and concrete in terms of economic aspects, it is difficult to sufficiently achieve physical properties such as compressive strength by using low calcium fly ash having mainly low activity. Only some cement components are being replaced by fly ash without systematic formulation selection by the system. Accordingly, in recent years, studies to improve compressive strength, flowability, thermal conductivity, etc., which are important physical properties as cement materials, including a large amount of fly ash, have been expanded.

The present inventors have studied in view of the above problems, as a result, by combining a chemical active agent in a fly ash to a specific composition can be produced cementless binder material excellent in compressive strength, using it, low cost, high strength, light weight, heavy metal adsorption It has been found that it is possible to provide mortar and concrete with sound absorption performance.

It is therefore an object of the present invention to provide a cementless binder comprising a fly ash and a chemical active agent.

Another object of the present invention is to provide a mortar and concrete having a low cost, high strength, light weight, heavy metal adsorption and sound absorption performance using the cement cement binder according to the present invention.

Still another object of the present invention is to provide a method for producing a cement binder paste using the cement binder according to the present invention.

According to one aspect of the present invention, there is provided a cementless binder comprising 60 to 87% by weight of fly ash, 10 to 35% by weight of calcium oxide (CaO) and 1 to 15% by weight of calcium chloride (CaCl ₂ ).

According to another aspect of the present invention, there is provided a cement mortar comprising the cement cement binder.

According to another aspect of the present invention, a cementless concrete including the cementless binder is provided.

According to another aspect of the present invention, a cementless concrete product including the cementless concrete is provided.

According to another aspect of the invention, (A) 60 to 87% by weight of fly ash, 10 to 35% by weight of calcium oxide (CaO) and 1 to 15% by weight of calcium chloride (CaCl ₂ ) to prepare a dry mixed powder step; And (B) mixing the prepared dry mixed powder with water to produce a paste, wherein the cement binder paste is prepared.

Since the cement binder is manufactured by recycling industrial by-products, it is environmentally friendly and has excellent compressive strength, dryness density, and heavy metal adsorption performance after curing. Accordingly, the mortar and concrete having low cost and high strength, light weight, heavy metal adsorption, and sound absorption performance can be provided using the cementless binder composition.

1 is a graph showing the compressive strength (MPa) according to the curing period (days) of cement cement binder (9 kinds) prepared from Example 1.

Figure 2 is a graph showing the compressive strength (MPa) according to the curing period (days) of cement cement binder (6 kinds) prepared from Example 2 and Comparative Example 1.

3 is a graph showing the results of measuring the dry density after curing the cement cement binder (6 kinds) prepared in Example 2 and Comparative Example 1 for 28 days.

4 is a graph showing the results of measuring the adsorption function of heavy metal (chromium) of CF_0.7, CCF_0.4 and CCF_0.7 cured in the form of blocks according to Preparation Example 2, and powder of CCF_ powder.

Hereinafter, the present invention will be described in more detail.

According to one aspect of the present invention, there is provided a cementless binder comprising 60 to 87% by weight of fly ash, 10 to 35% by weight of calcium oxide (CaO) and 1 to 15% by weight of calcium chloride (CaCl ₂ ).

Specifically, the fly ash may be referred to as ash generated after burning coal (that is, coal fly ash). For example, the fly ash refers to coal ash collected by a dust collector from flue gas of a boiler combusting pulverized coal. Accordingly, the fly ash is generated by incineration of paper ash sludge generated as a by-product from the paper mill, blast furnace slag obtained by collecting impurities from iron ore in the blast furnace, or incineration of general waste. It is a different material than waste.

Preferably, the fly ash may include _{SiO 2, Al 2 O 3,} Fe 2 O 3, CaO and MgO. Specifically, the fly ash may include SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , CaO and MgO in a weight ratio of 28.5 to 66.0: 12.5 to 55.0: 1.1 to 25.5: 1.4 to 22.4: 0.1 to 4.8. . More specifically, the fly ash may include SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , CaO and MgO in a weight ratio of 48.8 to 66.0: 17.0 to 27.8: 1.1 to 13.9: 3.1 to 10.1: 0.3 to 2.0 have. In addition, the fly ash may further include one or more components selected from the group consisting of Na ₂ O, K ₂ O, P ₂ O ₅ , TiO ₂ , MnO, and SO ₃ .

As a specific example, the fly ash may include the components described in Composition Examples 1 to 6 of Table 1 in parts by weight.

division	Composition of fly ash (parts by weight)
	Composition example 1	Composition example 2	Composition example 3	Composition example 4	Composition example 5	Composition example 6
SiO 2	28.5 ~ 59.7	37.8-58.5	35.6 ~ 57.2	50.2 ~ 59.7	48.8-66.0	28.5-66.0
Al 2 O 3	12.5-35.6	19.1 ~ 28.6	18.8-55.0	14.0 ~ 32.4	17.0 ~ 27.8	12.5-55.0
Fe 2 O 3	2.6-21.2	6.8-25.5	2.3-19.3	2.7-14.4	1.1-13.9	1.1-25.5
CaO	0.5-28.9	1.4-22.4	1.1-7.0	0.6-2.6	2.9 to 5.3	1.4-22.4
MgO	0.6 to 3.8	0.7 ~ 4.8	0.7 ~ 4.8	0.1-2.1	0.3 ~ 2.0	0.1-4.8
Na 2 O	0.1-1.9	0.3 ~ 1.8	0.6 ~ 1.3	0.5 ~ 1.2	0.2-1.3	0.1-1.9
K 2 O	0.4-4	0.9-2.6	0.8 ~ 0.9	0.8 ~ 4.7	1.1 to 2.9	0.4-4.7
P 2 O 5	0.1-1.7	0.1-0.3	1.1 to 1.5	0.1-0.6	0.2-3.9	0.1-3.9
TiO 2	0.5-2.6	1.1 to 1.6	0.2-0.7	1.0-2.7	1.3 ~ 3.7	0.2-3.7
MnO	0.03-0.2	-	-	0.5-1.4	-	0 to 1.4
SO 3	0.1-12.7	0.1-2.1	1.0-2.9	-	0.1-0.6	0-12.7

By including the fly ash of the above composition, the workability is improved when manufacturing the cement binder, the heat of hardening is alleviated, the long-term strength is improved, and the material separation between the binder and water is reduced even at a high water / binder ratio (W / B). It can happen and be economical.

The calcium oxide acts as a chemical activator for expressing strength, but fly ash and calcium oxide alone are difficult to express strength. Specifically, when calcium chloride is additionally included, calcium chloride acts as a chemical activator for accelerating the expression rate of strength. It was confirmed that the strength was significantly improved.

That is, when curing the cement binder, the strength of the C-S-H (calcium-silicate-hydrate) increases depending on the reaction of the components. In addition, the calcium chloride may improve the adsorption capacity of heavy metals by reacting with other components in the curing process to generate hydrocalumite.

The fly ash is included 60 to 87% by weight relative to the weight of the cement binder. When the content of the fly ash is within the above range, workability in manufacturing is improved, heat of curing is alleviated, strength is improved, and material separation between binder and water may occur less even at a high water / binder ratio (W / B). .

The calcium oxide is included in 10 to 35% by weight based on the weight of the cement cement binder. When the calcium oxide is less than 10% by weight based on the weight of the cement binder, it is difficult to express the strength, and when it exceeds 35% by weight, it is impossible to form a paste mixed with fly ash, calcium oxide, calcium chloride and water.

The calcium chloride is contained in 1 to 15% by weight based on the weight of the cement cement binder. When the content of calcium chloride is out of the above range, the strength after curing significantly decreases.

As a preferred example, the cementless binder may include 70 to 85% by weight of fly ash, 12 to 27% by weight of calcium oxide, and 3 to 10% by weight of calcium chloride, based on the weight thereof. Alternatively, the cementless binder may include 70 to 78% by weight of fly ash, 16 to 24% by weight of calcium oxide, and 6 to 10% by weight of calcium chloride. Alternatively, the cementless binder may include 72 to 76 wt% of fly ash, 18 to 22 wt% of calcium oxide, and 6 to 8 wt% of calcium chloride.

As another preferred example, the cementless binder may be a mixture of 13 to 50 parts by weight of calcium oxide and 1 to 17 parts by weight of calcium chloride based on 100 parts by weight of the fly ash. Alternatively, the calcium oxide may be mixed in an amount of 17 to 40 parts by weight, more preferably 3 to 15 parts by weight based on 100 parts by weight of the fly ash. Alternatively, the calcium oxide may be mixed in an amount of 25-30 parts by weight, more preferably 7-9 parts by weight, based on 100 parts by weight of the fly ash. At this time, the weight ratio of each component may be adjusted within the range of the content in the cement cement binder does not deviate from 60 to 87% by weight, 10 to 35% by weight of calcium oxide and 1 to 15% by weight of calcium chloride.

The cementless binder may have a compressive strength of 10 MPa or more, 15 MPa or more, preferably 20 MPa or more, 30 MPa or more, 40 MPa or more, or 45 MPa or more during curing for 28 days. For example, the cementless binder includes 70 to 85 wt% of the fly ash, 12 to 27 wt% of the calcium oxide, and 3 to 10 wt% of the calcium chloride, and may have a compressive strength of 20 MPa or more upon curing for 28 days. have. Specifically, the binder may have a compressive strength of 10 to 50 MPa, 15 to 50 MPa, 20 to 50 MPa, 30 to 50 MPa, 40 to 50 MPa, or 45 to 50 MPa during curing for 28 days. In general, the compressive strength of the binder is measured on the basis of 28 days after curing, it was confirmed that in the case of cementless binder according to the invention measured up to 40 ~ 50 MPa.

In addition, the binder may have a dry density of 0.85 to 1.2 g / cm 3 during curing for 28 days. The dry density means the density of the cured binder when the cured binder is dried at 100 to 110 ° C. until there is no variation in weight, and the moisture is not contained in the cured binder.

The cementless binder may have a hydrogen ion concentration (pH) in the range of 12.5 to 14. When the pH of the cement binder is within the above preferred range, it is possible to prevent corrosion of metals such as reinforcing bars and to sell in bags in powder form like Portland cement, and to be handled with less harm to the human body.

The cementless binder has a powder form and can be mixed with other materials to be used in construction or civil engineering.

As such, the cement binder has a high content of fly ash, which can significantly reduce carbon dioxide generation compared to conventional cement, and significantly lower the product cost by using low cost components. Physical properties such as can be exhibited.

In addition, the cement binder is high in strength and low in dry density after curing, it can exhibit a high strength and light weight characteristics, which complements the low strength of the weakness of the natural lightweight binder. In addition, the cement binder exhibits excellent physical properties in terms of adsorption of heavy metals after curing.

In addition, the cementless binder is not burned, unlike the existing organic insulating material, because it is made of a material that does not emit toxic gas can be used as a heat-resistant and non-flammable insulation and sound-absorbing material. In addition, the material can be used in a variety of construction or civil engineering sites because the flame resistance and non-combustibility can be maintained even if the curing conditions are different.

According to another aspect of the present invention, cementless mortar and cementless concrete including the cementless binder is provided.

According to another aspect of the present invention, a cementless concrete product including the cementless concrete is provided.

According to one embodiment, the cementless concrete product comprises concrete piles, bricks, blocks, tiles, boundary stones, sewer pipes, prestressed concrete, concrete panels, concrete pipes, aerated concrete, manholes, asphalt concrete, reinforced concrete, and concrete structures. It may include.

According to another aspect of the invention, (A) 60 to 87% by weight of fly ash, 10 to 35% by weight of calcium oxide (CaO) and 1 to 15% by weight of calcium chloride (CaCl ₂ ) to prepare a dry mixed powder step; And (B) is disclosed a method of producing a cement binder paste comprising the step of mixing the prepared dry mixed powder with water to produce a paste.

In the step (A), preferably 17 to 40 parts by weight of the calcium oxide and 3 to 15 parts by weight of the calcium chloride may be mixed with respect to 100 parts by weight of the fly ash. At this time, the mixing ratio of each component may be adjusted within the range of the content in the dry mixed powder 60 ~ 87% by weight, 10 ~ 35% by weight of calcium oxide and 1 ~ 15% by weight of calcium chloride.

In the step (B), 40 to 70 parts by weight of water may be mixed with respect to 100 parts by weight of the dry mixed powder. Particularly, when water is mixed at less than 40 parts by weight with respect to 100 parts by weight of the dry mixed powder, workability of the dough may be greatly reduced, and when it is mixed at more than 70 parts by weight, the curing time becomes considerably longer. The strength may drop sharply. The cement binder paste according to the present invention prepared by mixing water in the numerical range may have a large amount of internal voids after curing (curing), and thus may have an improved sound absorption effect, heat insulation effect, and heavy metal adsorption capacity. have. More specifically, 40 to 60 parts by weight of water or 40 to 50 parts by weight of water may be mixed with respect to 100 parts by weight of the dry mixed powder.

As an example, in the step (B) may be mixed with 40 to 50 parts by weight of water with respect to 100 parts by weight of the dry mixed powder, it may be more advantageous for the cement binder paste to exhibit a high compressive strength after curing within the blending ratio. . As another example, in the step (B) may be mixed with 60 to 70 parts by weight of water with respect to 100 parts by weight of the dry mixed powder, when the cemented binder binder is cured and dried after curing and drying in the blending ratio, high light weight, sound absorption and thermal insulation It may be more advantageous to exert.

According to one embodiment, in step (A), the dry mixed powder is prepared by mixing 70 to 85% by weight of fly ash, 12 to 27% by weight of calcium oxide and 3 to 10% by weight of calcium chloride; In step (B), 40 to 50 parts by weight of water may be mixed with respect to 100 parts by weight of the dry mixed powder. According to the above embodiment, the material separation between the binder and the water is reduced, the workability is improved, the initial crack is excellent, the state can be homogeneous while the long-term strength is excellent.

The cement binder paste thus prepared may be cured through curing. Specifically, the cement binder paste can be cured in a constant temperature and humidity conditions of 50 ~ 70 ℃ and relative humidity 70 ~ 100% range. More specifically, the curing may be carried out at a constant temperature and humidity conditions of 55 ~ 60 ℃ and 95 ~ 100% relative humidity. In addition, the curing may be performed for 3 to 30 days, or may be performed for 20 to 30 days.

In addition, during the curing, various building materials may be added to the cement binder paste. The additionally added building materials may be aggregates, fibers, binders, additives commonly used in construction or civil engineering.

When the cement binder paste is cured in the mold, it may be cured in a block form or the like. Alternatively, the cementless binder paste may be pulverized after curing and processed into a powder form. In particular, the powdered cementless binder after curing can significantly improve the heavy metal adsorption capacity. As an example, 60 to 70 parts by weight of water is mixed with 100 parts by weight of dry mixed powder containing 70 to 85% by weight of fly ash, 12 to 27% by weight of calcium oxide (CaO) and 3 to 10% by weight of calcium chloride (CaCl ₂ ). The powder obtained by curing and pulverizing the resulting paste can be very light and heavy metal adsorption capacity.

The cement binder paste is also used in concrete products such as concrete piles, bricks, blocks, tiles, boundary stones, sewer pipes, prestressed concrete, concrete panels, concrete pipes, aerated concrete, manholes, asphalt concrete, reinforced concrete, and concrete structures It can be cured in the form. Alternatively, the cementless binder paste may be applied to a construction site such as concrete construction and may be cured into a part of a building.

In addition, after the cement binder paste is cured, a large amount of internal voids may be formed through absolute drying. The absolute drying may be performed at a temperature condition of 80 ℃ to 120 ℃, more specifically 90 ℃ to 120 ℃, for example 100 ℃. In addition, the absolute drying may be performed for 12 to 36 hours, more specifically for 24 to 30 hours. As a result, the cutting density can be adjusted to 0.85 to 1.2 g / cm 3, or 0.85 to 1.0 g / cm 3.

The present invention will be described in more detail with reference to the following Examples. However, the following examples are only for illustrating the present invention, and the present invention is not limited thereto.

In the following examples, the fly ash obtained from the Hadong thermal power plant was used, the specific composition of the analysis by XRF results are as follows.

Fly Ash (Hadong Thermal Power Plant)
ingredient	Parts by weight
SiO 2	62.2
Al 2 O 3	22.8
Fe 2 O 3	6.0
CaO	3.1
K 2 O	1.6
TiO 2	1.3
MgO	1.0
Na 2 O	0.6
SO 3	0.6
P 2 O 5	0.3
BaO	0.1
SrO	0.1
ZrO 2	0.1

Example 1 Preparation of Cementless Binder

Fly ash, calcium oxide and calcium chloride were mixed at a weight ratio as shown in Table 3 below to prepare a total of nine dry mixed powders (cement free binder).

Sample	Fly ash (% by weight)	Calcium Oxide (wt%)	Calcium chloride (wt%)
One	87	10	3
2	82	15	3
3	77	20	3
4	84	10	6
5	79	15	6
6	74	20	6
7	81	10	9
8	76	15	9
9	71	20	9

Example 2: Preparation of Cementless Binder

Fly ash, calcium oxide and calcium chloride were mixed at a weight ratio as shown in Table 4 to prepare a total of four dry mixed powders (cement binder).

Sample	Fly ash (% by weight)	Calcium Oxide (wt%)	Calcium chloride (wt%)
One	75	20	5
2	65	30	5
3	70	20	10
4	60	30	10

Comparative Example 1: Preparation of Cementless Binder

Fly ash, calcium oxide and calcium chloride were mixed at a weight ratio as shown in Table 5 below to prepare a total of five dry mixed powders (cement free binder).

Sample	Fly ash (% by weight)	Calcium Oxide (wt%)	Calcium chloride (wt%)
One	80	20	0
2	70	30	0
3	60	40	0
4	55	40	5
5	50	40	10

Preparation Example 1 Preparation of Cementless Binder Paste

Pastes were formed by adding water to the dry mixed powder (cementless binder) having various compositions prepared in Examples 1 and 2 and Comparative Example 1, respectively. At this time, 40 parts by weight of water was added to 100 parts by weight of the dry mixed powder prepared in Example 1, and 70 parts by weight of water was added to 100 parts by weight of the dry mixed powder prepared in Examples 2 and Comparative Example 1.

Preparation Example 2 Curing of Cemented Binder Paste (Hardening)

Curing block was prepared by curing the cementless binder paste prepared in Preparation Example 1 for 28 days while maintaining the temperature at 60 ° C. and relative humidity of 70 to 100% in a cubic mold each having a width, length, and height of 50 mm.

Test Example 1: Evaluation of Compressive Strength

For 100 parts by weight of cement cement binder (9 kinds) prepared from Example 1, 40 parts by weight of water was added according to the procedures of Preparation Examples 1 and 2 to obtain a paste, and the cubes each having a width, a length, and a height of 50 mm each. Compressive strength at 3 and 28 days was measured while curing at 60 ° C. and 100% relative humidity in the mold. The compressive strength was measured according to the compressive strength test method of cement mortar described in KS L 5105 or JIS R 5201, and the average compressive strength of three specimens per sample was shown in Tables 6, 7, and 1 below. .

3-day compressive strength (MPa)		Calcium oxide weight ratio
		10 wt%	15 wt%	20 wt%
Calcium chloride weight ratio	3 wt%	21.5	27.2	30.0
	6 wt%	14.5	30.2	34.6
	9 wt%	12.2	25.3	34.8

28 Day Compressive Strength (MPa)		Calcium oxide weight ratio
		10 wt%	15 wt%	20 wt%
Calcium chloride weight ratio	3 wt%	25.3	33.9	36.9
	6 wt%	21.7	39.6	46.2
	9 wt%	16.5	33.7	44.6

As shown in Tables 6, 7, and 1, the highest strength was shown in the formulation of 20% by weight of calcium oxide and 6% by weight of calcium chloride (74% by weight fly ash) during the 28 days curing period.

In addition, to 100 parts by weight of cement cement binder (6 kinds) prepared from Example 2 and Comparative Example 1, 70 parts by weight of water was added according to the procedures of Preparation Examples 1 and 2 to obtain a paste. The compressive strengths of the 3rd and 28th days were measured while curing at 60 ° C. and 100% relative humidity in a 50 mm cube mold. The compressive strength was measured according to the compressive strength test method of cement mortar described in KS L 5105 or JIS R 5201, and the average compressive strength of three specimens was taken for each sample and shown in Tables 8 and 9, and FIG. 2. .

3-day compressive strength (MPa)		Calcium oxide weight ratio
		20 wt%	30 wt%	40 wt%
Calcium chloride weight ratio	0 wt%	2.2	3.4	Molding impossible
	5 wt%	8.7	11.9	Molding impossible
	10 wt%	17	20.6	Molding impossible

28 Day Compressive Strength (MPa)		Calcium oxide weight ratio
		20 wt%	30 wt%	40 wt%
Calcium chloride weight ratio	0 wt%	6.3	8.5	Molding impossible
	5 wt%	18.9	27	Molding impossible
	10 wt%	24.4	31.1	Molding impossible

As shown in Table 8 and 9, and Figure 2, the highest strength in the combination of 30% by weight of calcium oxide and 10% by weight of calcium chloride (60% by weight fly ash) for 28 days curing period. In addition, when the content of calcium oxide was more than 30% by weight (more than 50 parts by weight based on 100 parts by weight of the fly ash), molding of the paste itself was impossible.

Test Example 2: Measurement of dry density

To 100 parts by weight of cement cement binder (6 kinds) prepared from Example 2 and Comparative Example 1, 70 parts by weight of water was added according to the procedures of Preparation Examples 1 and 2 to obtain a paste, and then the width, length, and height were respectively. Cured for 28 days at 60 ℃ and 100% relative humidity in a 50mm cube mold. It was shown in Figure 3 the dry density measured by drying for one day at 100 ℃.

3 and Tables 6 to 9, the cement cement binder according to the present invention exhibits high strength and light weight after curing (curing) is low, it can be seen that can replace the commercial cement.

Test Example 3 Evaluation of Heavy Metal (Chrome) Adsorption Function

The paste obtained by adding water to the cement cement binder (dry mixed powder) prepared in Example 2 and Comparative Example 1 was maintained at 60 ° C. and a relative humidity of 70 to 100% in a cubic mold each having 50 mm in width, length, and height. Each cured block sample was prepared by curing for 3 days. In addition, some cured block samples were ground to obtain cured powder samples. The binder composition, mixing ratio with water, and crushing of each of these cured blocks and cured powder samples are summarized in Table 1 below. In addition, the dry density of the hardened block samples was measured and summarized together in Table 1.

Sample Type	Cementless binder (% by weight)			Water (parts by weight) (per 100 parts by weight of cementless binder)	Crushing	Drying density (g / cm 3)
	Fly ash	Calcium oxide	Calcium chloride
CF_0.7	80	20	0	70	-	0.95
CCF_0.4	70	20	10	40	-	1.2
CCF_0.7	70	20	10	70	-	0.94
CCF_Powder	70	20	10	70	smash	-

The samples were immersed in a chromium solution at 415.5 mg / L for 2 days to adsorb chromium, and the chromium concentration (before and after adsorption) of the aqueous chromium solution was measured using ICP-OES equipment, and is shown in FIG. 4.

In Table 10, CCF_0.7 has a lower dry density than CCF_0.4, while in Figure 4, heavy metal (chromium) adsorption capacity is relatively higher than CCF_0.4, and the lower the dry density, the more voids are formed. This means that the adsorption of heavy metals can be carried out more easily.

In addition, in Table 10, CF_0.7 according to the comparative example is similar to CCF_0.7 and cutting density according to the embodiment, but in Figure 4 it was evaluated that the heavy metal (chromium) adsorption capacity is much lower than CCF_0.7. This is due to the fact that CF_0.7 does not contain calcium chloride, so that no reaction product hydrocalumite was produced.

In addition, in the case of CCF_powder obtained by pulverizing the hardening block, when immersed in the chromium solution, it was confirmed that the chromium concentration after 2 days was significantly reduced to 62.5% compared to the initial chromium concentration due to the surface area improvement.

Therefore, it can be seen from FIG. 4 that the mixing ratio of the binder and water as well as the inclusion of calcium chloride also contribute to the heavy metal adsorption function. Also, when the hardened block is pulverized into powder, the heavy metal adsorption capacity is higher than that of the block state. It was confirmed that this is improved.

Claims (15)

1. Cement cement binder comprising 60 to 87% by weight of fly ash, 10 to 35% by weight of calcium oxide (CaO) and 1 to 15% by weight of calcium chloride (CaCl ₂ ).
2. The method of claim 1,

   70 to 85% by weight of the fly ash, 12 to 27% by weight of the calcium oxide and 3 to 10% by weight of the calcium chloride, cementless binder.
3. The method of claim 1,

   Cerium cement binder, characterized in that 17 to 40 parts by weight of the calcium oxide and 3 to 15 parts by weight of the calcium chloride are mixed with respect to 100 parts by weight of the fly ash.
4. The method of claim 1,

   SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , CaO and MgO 28.5 to 66.0: 12.5 to 55.0: 1.1 to 25.5: 1.4 to 22.4 as ash fly generated after the fly ash burned coal (coal fly ash) Cement cement binder, characterized in that it comprises in a weight ratio of 0.1 to 4.8.
5. The method of claim 1,

   Cementium binder, characterized in that the cementless binder has a hydrogen ion concentration (pH) of 12.5 to 14.
6. The method of claim 1,

   The cementless binder is characterized in that it has a compressive strength of 10 MPa or more when cured for 28 days.
7. The method of claim 1,

   The cement binder is

   70 to 85 wt% of the fly ash, 12 to 27 wt% of the calcium oxide, and 3 to 10 wt% of the calcium chloride,

   Cement cement binder, characterized in that having a compressive strength of 20 MPa or more during 28 days curing.
8. Cement cement mortar comprising the cement cement binder according to any one of claims 1 to 7.
9. A cementless concrete comprising a cementless binder according to any one of claims 1 to 7.
10. Cementless concrete product comprising cementless concrete according to claim 9.
11. The method of claim 10,

    Concrete, characterized in that the concrete product comprises concrete piles, bricks, blocks, tiles, boundary stones, sewer pipes, prestressed concrete, concrete panels, concrete pipes, aerated concrete, manholes, asphalt concrete, reinforced concrete, and concrete structures product.
12. (A) preparing a dry mixed powder mixed with 60 to 87% by weight of fly ash, 10 to 35% by weight of calcium oxide (CaO) and 1 to 15% by weight of calcium chloride (CaCl ₂ ); And

    (B) mixing the water to the prepared dry mixed powder to produce a paste, comprising the cement binder paste.
13. The method of claim 12,

    In the step (A), characterized in that 17 to 40 parts by weight of calcium oxide and 3 to 15 parts by weight of calcium chloride are mixed with respect to 100 parts by weight of the fly ash, the cement binder paste manufacturing method.
14. The method of claim 12,

    In the step (B), 40 to 70 parts by weight of water is mixed with respect to 100 parts by weight of the dry mixed powder, the cement binder paste manufacturing method.
15. The method of claim 12,

    In step (A), the dry mixed powder is prepared by mixing 70-85 wt% of fly ash, 12-27 wt% of calcium oxide and 3-10 wt% of calcium chloride;

    In step (B), characterized in that 40 to 50 parts by weight of water is mixed with respect to 100 parts by weight of the dry mixed powder, manufacturing method of cement binder paste.

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