JPH08169734A - Quick hardening clinker composition - Google Patents

Abstract

PURPOSE: To produce a quick hardening clinker composition easy for production by using a rotary kiln, etc., to sinter a melted liq. as a medium, hardly causing remaining of free CaO and capable of quick hardening not only at normal temp. but also at low temp. CONSTITUTION: In a clinker used in the quick hardening cement, 0.1-50wt.% 2CaO.SiO2 based calcium silicate phase and/or 2CaO.Al2 O3 .SiO2 based calcium aluminosilicate phase are allowed to coexist and 3CaO.SiO2 based calcium silicate phase is not allowed to coexist as a mineral phase in the clinker composition in which 0.1-9wt.% Fe2 O3 and 0.1-9wt.% CaF2 are allowed to coexist respectively in the clinker consisting essentially of 12CaO.7Al2 O3 . In this way, various problems on C12 A7 production by an electrofusing method. for example, a sudden rise of production cost are solved.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to improvements in clinker used in rapid hardening cement.

[0002]

2. Description of the Related Art Jet clinker, erwin type clinker, alumina cement clinker and the like have been conventionally used as clinker used for rapid hardening cement. Also, 12CaO, which is a rapid hardening component
Use of a clinker obtained by synthesizing amorphous C ₁₂ A ₇ by melting a clinker containing 7Al ₂ O ₃ (hereinafter abbreviated as C ₁₂ A ₇ ) as a main component and then rapidly cooling it Is being considered.

However, the above-mentioned jet cement clinker contains 3CaO.SiO ₂ (hereinafter abbreviated as C ₃ S) type calcium silicate phase as a main component and 11CaO.7Al ₂ O ₃ .CaF ₂ (hereinafter referred to as a rapid hardening component). , C ₁₁ abbreviated as a ₇ · CaF _2.) the a clinker containing 30 wt% to 20 wt%, at the time of firing C ₁₁
A ₇ · CaF ₂ is to present as a melt phase. Therefore, since the content of C ₁₁ A ₇ · CaF ₂ which is a quick-hardening component is small, it does not have sufficient quick-hardening property.
It was not satisfactory as a clinker for rapid hardening cement. In order to solve such a problem of jet cement clinker, C ₁₁ A ₇
The content of CaF ₂ was increased to about 60% by weight, and C ₃ S was added to 2
A method of about 0 to 25% by weight is also considered, but with this method, the melt phase increases excessively during firing, and it is difficult to manufacture by a sintering method using a melt such as a rotary kiln as a medium. However, there is a problem that a large amount of free CaO remains.

The above-mentioned erwin-based clinker contains 70% by weight or more of erwin (4CaO.3Al ₂ O ₃ · SO ₃ ) having a rapid hardening property, so that it is used as a clinker for rapid hardening cement. There is a drawback that the cement using the clinker cures slowly at low temperature, for example, 5 ° C. The above-mentioned alumina cement clinker has CaO.Al ₂ O ₃ (hereinafter abbreviated as CA) as a main component, but has a drawback that it is inferior in rapid hardening property to a clinker having C ₁₂ A ₇ as a main component. there were. In addition, the cement produced by using the clinker obtained by synthesizing the amorphous C ₁₂ A ₇ by melting the clinker containing C ₁₂ A ₇ which is a rapid hardening component as a main component and then rapidly cooling it is Also has a rapid hardening property, which solves the problem of the rapid hardening cement using the Irwin type clinker. However, this manufacturing method has a problem that special equipment for melting and amorphizing the clinker is required, and
When the electrofusion method is used for melting the clinker, there is a problem that a large amount of electric power is consumed, the electric power cost becomes high, and the manufacturing cost rises.

[0005]

The present invention has been made in view of the above circumstances and is easy to manufacture using a rotary kiln or the like in which a melt is used as a medium for sintering, and free C
It is to provide a rapid-curing clinker composition in which aO is unlikely to remain and which is fast in curing not only at room temperature but also at low temperature.

[0006]

In order to solve the problems of the conventional clinker as described above, the inventor of the present application conducted a study on a hydration reaction of a calcium aluminate clinker synthesized by a sintering method, C, which is a rapid hardening component
_{11 When} firing the clinker containing A ₇ · CaF ₂ as the main component,
2CaO · SiO ₂ (hereinafter abbreviated as C ₂ S) -based calcium silicate phase and / or 2CaO · Al ₂ O ₃ ·
By coexisting a SiO ₂ (hereinafter abbreviated as C ₂ AS) -based calcium aluminosilicate phase, C ₃ S
It was found that the hydration reactivity of C ₁₁ A ₇ .CaF ₂ can be increased as compared with the case of coexisting with, and the present invention was accomplished.

That is, the quick-setting clinker composition according to claim 1 of the present invention is used for preventing hydration delay due to hardening-promoting organic substances such as quick-setting cement, quick-setting material, quick-setting cement, ground improvement material and masking material. The clinker containing C ₁₂ A ₇ as a main component, and Fe ₂ O ₃ in an amount of 0.1 to 9 wt% and CaF ₂ in an amount of 0.1 to 9% by weight.
Clinker composition obtained by co wt%, respectively, C ₂ S system calcium silicate phase as a mineral phase and / or C ₂ AS-based calcium aluminosilicate phase was a whole from 0.1 to 50% by weight coexistence, and C It is characterized in that the ₃ S-based calcium silicate phase is not allowed to coexist.

Further, the rapid hardening clinker composition according to claim 2 is the rapid hardening clinker composition according to claim 1 in which the clinker containing C ₁₂ A ₇ as a main component is C ₁₂ A ₇ as a mineral phase. The content of 3CaO.Al ₂ O ₃ (hereinafter abbreviated as C ₃ A) or CA in the calcium aluminate phase is 50% by weight or more, and the proportion of CA is 0 to 25% by weight. It is characterized by being.

The rapid-setting clinker composition according to claim 3 is the rapid-setting clinker composition according to claim 1 or 2, wherein the C ₁₂ A _7- based calcium aluminate phase is
C ₁₁ A ₇ · CaF ₂ alone or C ₁₁ A ₇ · CaF ₂ and C
It is characterized by being a mixture with ₁₂ A ₇ .

[0010]

According to the rapid hardening clinker composition of the present invention, C
Fe ₂ O ₃ 0.1 to 9% by weight and CaF ₂ 0.1 to 9% by weight in the clinker mainly composed of ₁₂ A _7.
By using the clinker composition coexisting with each other, when this is sintered, CaF ₂ becomes CaO and Al ₂
O ₃ reacts with generating the C ₁₁ A ₇ · CaF ₂ having a high temperature melt phase, Fe ₂ O ₃ is low melt phase reacts similarly to CaO and Al ₂ O ₃ CaO-Al ₂ O ₃ -Fe to produce a ₂ O ₃ based material. Therefore, by generating the high-temperature melt phase and the low-temperature melt phase, the difference in the melt generation temperature between them becomes large, so that the high-temperature melt phase is the solid phase and the coexisting low-temperature melt phase is the melt. Phase temperature range, ie C ₁₁ A ₇ · CaF ₂
Is not melted, and the CaO—Al ₂ O ₃ —Fe ₂ O ₃ based material is melted, and the temperature range corresponding to the above-mentioned melt generation temperature difference is set as the sintering temperature. It is possible to bake the clinker. In addition, in the above clinker composition, a C ₂ S-based calcium silicate phase and / or C ₂ AS is added as a mineral phase.
Calcium aluminosilicate phase of the entire system 0.1 ~
By making 50% by weight coexist and not allowing the C ₃ S-based calcium silicate phase to coexist, the lime saturation is lowered, so that a large amount of free CaO can be prevented.

The rapid hardening clinker composition of the present invention will be described in detail below. The rapid-setting clinker composition (A) of the present invention comprises a rapid-setting cement, a quick-setting material, a quick-setting cement,
Soil improvement material, a clinker used by the masking material such as hardening accelerator organics for hydration delay preventing, C ₁₂ A ₇
Fe ₂ O ₃ was added to the clinker mainly composed of
To 9% by weight, clinker composition consisting coexist CaF _2, respectively 0.1 to 9% by weight of the total (B), the calcium silicate phases C ₂ S system as mineral phase and / or C ₂ A
The total amount of S-based calcium aluminosilicate phase is 0.1
˜50% by weight, and no C ₃ S-based calcium silicate phase is allowed to coexist.

The clinker containing C ₁₂ A ₇ as a main component contains, as a mineral phase, a C ₁₂ A ₇ system and a calcium aluminate phase such as C ₃ A and CA of 50% by weight or more, preferably 70%.
The content of C ₃ A or CA in the calcium aluminate phase is 0 to 25% by weight, and most of the C ₁₂ A ₇ minerals are present as a crystalline phase. The C ₁₂ A _7- based calcium aluminate phase is C ₁₁ A ₇ · CaF ₂ alone or C ₁₁ A ₇ · CaF ₂
And a mixture of C ₁₂ A _7.

When the amount of the calcium aluminate phase is less than 50% by weight, the content of C ₁₂ A ₇ which is a quick-hardening component is small, and it is not suitable as a clinker for quick-hardening cement as in the case of jet cement clinker. It is not preferable because it becomes sufficient. Therefore, in the clinker containing C ₁₂ A ₇ as a main component in the rapid-curing clinker composition (A) of the present invention, it is not only necessary to set the amount of the calcium aluminate phase to 50% by weight or more, but also to secure the rapid-hardening property. From the viewpoint, in order to increase the amount of C ₁₂ A ₇ mineral as much as possible, it is preferable to secure the amount of calcium aluminate phase of 70% by weight or more. The content of C ₃ A or CA in the calcium aluminate phase is preferably 25% by weight or less.

In the rapid-hardening clinker composition (A) of the present invention, the clinker containing C ₁₂ A ₇ as a main component as described above and Fe ₂ O ₃ as a melt forming component in a total amount of 0.1
A clinker composition (B) is obtained by adding and coexisting within a range of from 9% by weight to 9% by weight, and adding CaF ₂ within a range of from 0.1% by weight to 9% by weight of the whole. . Thus, by coexisting Fe ₂ O ₃ and CaF ₂ , the low temperature melt phase (CaO-Al ₂ O ₃
-Fe ₂ O ₃ system) and a high temperature melt phase (C ₁₁ A ₇ · CaF ₂ system) are generated respectively, thereby expanding the melt generation temperature difference, and firing the clinker within this temperature range is possible. I did it.

Here, the amount of Fe ₂ O ₃ added is in the above range because when the amount added is less than 0.1% by weight, the amount of low-temperature melt phase produced is insufficient and melt such as in a rotary kiln is used. This is because it becomes difficult to manufacture by a sintering method using as a medium. On the other hand, when the addition amount exceeds 9% by weight, the low temperature melt phase increases too much, and the melt is melted in the same manner as in the above-mentioned few cases. the production of a sintering method with medium becomes difficult, yet the content of C ₁₂ a ₇ based mineral becomes less is steeper rigid component, because rapid hardening is reduced. Further, the amount of CaF ₂ added is in the above range, because if the amount added is less than 0.1% by weight, the expansion of the melt generation temperature between the low temperature melt phase and the high temperature melt phase becomes insufficient, and again the rotary kiln This is because it becomes difficult to manufacture by a sintering method using a melt as a medium as described above. On the other hand, when the addition amount exceeds 9% by weight, the high temperature melt phase increases too much, and as in the case it is difficult to manufacture in a sintering process to medium melt, yet will be the content of C ₁₂ a ₇ mineral is steeper rigid component becomes small, because rapid hardening is reduced.

When the clinker composition (B) thus obtained is sintered, CaF ₂ reacts with the fast-hardening components CaO and Al ₂ O ₃ to form a high temperature melt phase C.
₁₁ A ₇ · CaF ₂ is produced, and Fe ₂ O ₃ is converted to CaO and Al ₂
O ₃ becomes the low-temperature melt phase reacts with CaO-Al ₂ O ₃ -F
e ₂ O ₃ type substance is produced. Therefore, the temperature range in which the high-temperature melt phase is the solid phase and the coexisting low-temperature melt phase is the melt phase, that is, C ₁₁ A ₇ .CaF ₂ is not dissolved, and CaO--Al
_By setting the temperature range in which the ₂ O ₃ —Fe ₂ O ₃ based material melts to the sintering temperature, the clinker can be fired by a sintering method using a rotary kiln or the like.

Furthermore, in the rapid hardening clinker composition (A) of the present invention, the clinker composition (B) as described above is added to
C ₂ S-based calcium silicate phase as mineral phase and /
Alternatively, the C ₂ AS-based calcium aluminosilicate phase is allowed to coexist in an amount of 0.1 to 50% by weight, preferably 0.1 to 30% by weight, and the C ₃ S-based calcium aluminosilicate phase is not allowed to coexist. Here, the coexisting amount of the C ₂ S-based calcium silicate phase and / or the C ₂ AS-based calcium aluminosilicate phase is set to the above range because a natural raw material is used when the coexisting amount is less than 0.1% by weight. This is because, in practice, composition design becomes difficult, while
When the coexisting amount exceeds 50% by weight, C ₁₂ which is a rapid hardening component is used.
This is because the content of the A ₇ type calcium aluminate phase is reduced. In addition, when the C ₃ S-based calcium silicate phase is contained, the lime saturation increases and free CaO
However, there is a problem that it becomes easy to remain.

[0018]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. (Experimental Example 1) A clinker composition having a composition shown in Table 1 was synthesized by a sintering method, and a comparative test of rapid hardness was performed.

[0019]

[Table 1]

In the rapid hardness comparison test, a trial-made clinker was pulverized to obtain a rapid-hardening clinker powder, and a proctor penetration resistance test (5 ° C., 20 ° C.) was carried out by the following procedure using these clinker powders. . Kneading of mortar using ordinary cement was carried out in accordance with JIS R 5201 and then allowed to stand for 30 minutes, after which rapid hardening clinker powder was added and kneaded for 30 seconds and subjected to a proctor penetration resistance test. The proctor penetration resistance test was performed according to the setting test method of concrete (JIS A 6204). The results are shown in Table 2 and FIG. Figure 1
It is a graph which showed the time-dependent change of the penetration resistance value in 5 degreeC.

[0021]

[Table 2]

As is clear from the results shown in Table 2 and FIG. 1, the mortar using the clinker composition of this example is not only at 20 ° C. It can be seen that even at 5 ° C, the initiation and termination time of setting is fast, excellent rapid hardening is exhibited, and free lime (free CaO) hardly remains.

(Experimental Example 2) A clinker composition having a composition shown in Table 3 was synthesized by a sintering method, and a heat rate of hydration (cal / cal) of a calcium silicate phase coexisting with C ₁₁ A ₇ .CaF ₂ (cal /
A comparative test was conducted for the effect on g · hr).

[0024]

[Table 3]

In the comparative test of hydration heat generation rate, a trial clinker was pulverized to a fineness of 8500 cm ² / g to obtain a rapid-hardening clinker powder, and these clinker powders were used to measure at 20 ° C. by a conduction calorimeter. ,
The hydration heat generation rate was measured under the condition of water / cement ratio = 1.
The result is shown in FIG. FIG. 2 is a graph showing the influence of the coexisting calcium silicate phase on the hydration heat generation rate,
In FIG. 2, curve a shows the relationship between the hydration time and the hydration exothermic rate when the clinker composition of Example 9 was used, and curve b was the water when the clinker composition of Example 10 was used. The relationship between the summing time and the hydration heat generation rate is shown.
Shows the relationship between the hydration time and the hydration exothermic rate when the clinker composition of Example 2 was used, and the curve D shows the relationship between the hydration time and the hydration exothermic rate when the clinker composition of Comparative Example 3 was used. It is shown.

As is clear from the results shown in FIG. 2, when the clinker composition of this example in which the calcium silicate phase is C ₂ S is used, the clinker composition of the comparative example in which C ₃ S coexists. Since the peak time is faster and the peak height is higher than the case of using the product, it is understood that the hydration heat generation rate is fast and the excellent rapid hardening property is exhibited.

(Experimental Example 3) Clinker compositions having the compositions shown in Tables 4 and 5 were synthesized by a sintering method using a rotary kiln, and bending strength (5 ° C), compressive strength (5 ° C) and handling time (5 ° C). ) Was carried out.

[0028]

[Table 4]

[0029]

[Table 5]

A comparative test of bending strength, compressive strength, and handling time was carried out by crushing a trial clinker to prepare a rapid-hardening clinker powder, and using the clinker powder according to the following procedure.

[0031]

[Table 6] In Table 6, JET-A represents jet cement A type and HC represents early strength cement. ,

A cement having the composition shown in the above Table 6 was produced as a trial and JI
A mortar strength test was conducted according to S R 5201.
Regarding handling time, diameter 1 inch, height 2
Using an inch measuring cone, adjust so that the total amount of drop when attached to the biger needle device would be 350 g, then fill it in a coagulation test frame in the same manner as the flow test according to JIS R 5201, and then add the cone of the biger needle device. Set the point of contact with the surface of the mortar and read the depth of penetration when descending, and the time when the depth of penetration was 1.5 mm was taken as the handling time (based on water injection). . The results are shown in Table 7.

[0033]

[Table 7] In Table 7, h is time, d is day, h-m is hour-minute, and the strength ratio is 100% as the compressive strength of the mortar using the clinker composition of Comparative Example 4 after 3 hours. 3 shows the ratio of the compressive strength of a mortar using the clinker composition of Example 3 after 3 hours.

As is clear from the results shown in Table 7, the mortar using the clinker composition of this example has a higher compressive strength than the mortar using the clinker composition of the comparative example at an earlier time, for example, 3 hours. It can be seen that the value is large and that it exhibits excellent rapid hardening.

(Experimental Example 4) A clinker composition having the composition shown in Table 8 was synthesized by a sintering method, and a comparative test of compressive strength (20 ° C) was carried out.

[0036]

[Table 8] In Table _{8, C 11 A 7 · CaF} 2 , the calcination temperature 1300 ° C., is of fineness 6500 cm ² / g.

In the comparative test of compressive strength, a trial clinker was pulverized, and this was used as a quick-hardening clinker powder, and a cement having the composition shown in Table 9 was made as a trial to perform a mortar strength test according to JIS R5201. It was The results are also shown in Table 9.

[0038]

[Table 9]

As is clear from the results shown in Table 9, the mortar using the clinker composition of this example had a shorter time at 20 ° C. than the mortar using the clinker composition of the comparative example. For example, it can be seen that the compressive strength value is large at 3 h and that the excellent rapid hardening property is exhibited.

[0040]

As described above, the rapid-curing clinker composition of the present invention contains 0.1 to 9% by weight of Fe ₂ O ₃ and CaF ₂ in the clinker containing C ₁₂ A ₇ as a main component. throughout clinker composition obtained by co 0.1 to 9% by weight each, the whole C ₂ S system calcium silicate phase and / or C ₂ aS-based calcium aluminosilicate phase as a mineral phase 0.1-50 % Coexistence, and C
_{Since the 3} S-based calcium silicate phase is not allowed to coexist, the production using a rotary kiln or the like in which a melt is used as a medium is facilitated, and various C ₁₂ A ₇ production methods by the electrofusion method are facilitated. There is an advantage that problems such as soaring manufacturing costs can be solved and free CaO hardly remains. Also, as a clinker for rapid hardening cement,
Since the content of the fast-curing component is large and the curing is fast not only at room temperature but also at low temperature, it is an excellent solution to the problems of conventional rapid-curing clinker. In addition, the rapid-curing property is far superior to that of the clinker in which the amount of C ₁₁ A ₇ · CaF ₂ which is a fast-hardening component in the conventional jet cement is simply increased.

[Brief description of drawings]

FIG. 1 is a graph showing a change with time of a penetration resistance value at 5 ° C.

FIG. 2 is a graph showing the influence of the coexisting calcium silicate phase on the heat-up rate of hydration.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location // C09K 103: 00 (72) Inventor Shigehiro Ando 1 Kanda Mitoshiro-cho, Chiyoda-ku, Tokyo Sumitomo Osaka Cement Co., Ltd. (72) Inventor Masao Sato 7-1-55 Minami Enkajima, Taisho-ku, Osaka City, Osaka Prefecture Sumitomo Osaka Cement Co., Ltd. Central Research Center / Sement Concrete Research Lab.

Claims (3)

[Claims] 1. A clinker used for preventing hydration delay due to hardening-promoting organic substances such as quick-setting cement, quick-setting material, quick-setting cement, ground improvement material, and masking material.
Fe is added to the clinker containing CaO · 7Al ₂ O ₃ as the main component.
₂ O ₃ is 0.1 to 9% by weight of the whole, and CaF ₂ is 0.
In the clinker composition coexisting with 1 to 9% by weight, 2CaO.SiO ₂ -based calcium silicate phase and / or 2CaO.Al ₂ O ₃ .SiO ₂ -based calcium aluminosilicate phase is added as a mineral phase. 1-5
A rapid-hardening clinker composition, characterized in that 0 wt% is allowed to coexist and a 3CaO.SiO ₂ -based calcium silicate phase is not allowed to coexist. _2. A clinker containing 12CaO.7Al ₂ O ₃ as a main component has a mineral phase of 12CaO.7Al ₂
50% by weight of calcium aluminate phase consisting of O ₃ system
3 contained in the above and occupying the calcium aluminate phase
The ratio of CaO · Al ₂ O ₃ or CaO · Al ₂ O ₃ is 0 to 2
The rapid hardening clinker composition according to claim 1, which is 5% by weight. 3. The 12CaO.7Al ₂ O ₃ -based calcium aluminate phase comprises 11CaO.7Al ₂ O ₃ .CaF ₂
Alone or 1 with 11CaO ・ 7Al ₂ O ₃・ CaF ₂
The rapid-hardening clinker composition according to claim 1 or 2, which is a mixture with 2CaO · 7Al ₂ O ₃ .