JP3179702B2 - Hardened clinker composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a rapidly hardening cement,
The present invention relates to a rapidly hardening clinker composition used for a quick setting material, a quick setting cement, a ground improvement material, a masking material and the like.

[0002]

2. Description of the Related Art Conventionally, jet-hardening clinker compositions used for quick-hardening cements, quick-setting materials, quick-hardening cements, soil improvement materials, masking materials and the like include jet cements (calcium). Silicate as main component, 12CaO · 7Al as rapid hardening component
₂ O ₃ (hereinafter _C 12 _{A 7} hereinafter) based calcium clinker aluminate phase containing 20 to 30 wt%], Erwin-based clinker [3CaO _· 3Al ₂ O 3 _· Ca
SO ₄ (hereinafter abbreviated as C ₄ A ₃ SO ₃ ) as a main component], alumina cement clinker [CaO.Al ₂ O
₃ (hereinafter abbreviated as CA) as a main component].

However, the conventional rapid-hardening clinker composition has a problem that the amount of the quick-hardening component is insufficient and the rapid-hardening property at room temperature or low temperature is inferior due to the characteristics of the quick-hardening component.

[0004] In order to solve this problem, melting the C ₁₂ A ₇ based calcium aluminate as a main component clinker is steeper rigid component, then, amorphous C ₁₂ by quenching it methods for synthesizing a ₇ has also been studied.

[0005] The clinker containing C ₁₂ A ₇ as a main component has excellent characteristics in terms of rapid hardening, but has the following inconvenience in the production thereof.

That is, in such a clinker, the temperature range in which the solid phase and the melt phase coexist is narrow, and the solid phase is easily melted by a slight temperature change. However, it was difficult to manufacture by a method of sintering with a medium.

Further, in the production of the clinker, when the electrofusion method is used for melting the clinker, the clinker is melted at a high temperature, so that there is a problem that power and equipment costs are increased, and the production cost is increased. are doing.

To solve the above-mentioned problems, Japanese Patent Laid-Open No.
The No. -115986, and those of _C 12 _{A 7} based as mineral phase, 3CaO · _Al 2 _{O 3} (hereinafter, _{C 3} A hereinafter) and a calcium aluminate such or CA, in the total amount of 50 wt% The clinker raw material containing C ₁₂ A ₇ as a main component contains Fe ₂ O ₃ in an amount of 0.1 to 9% by weight based on the total weight of the clinker raw material.
Rapid hardening clinker composition characterized by comprising a CaF ₂ was added each 0.1 to 9% by weight of the total have been disclosed.

The clinker composition comprises Fe ₂ O ₃ and C
By adding aF ₂ , a low-temperature melt phase and a high-temperature melt phase are generated, the difference between the melt formation temperatures is enlarged, and the temperature range corresponding to the melt formation temperature difference is set as the sintering temperature. It is characterized by the following.

However, in the case of manufacturing by a method of sintering a melt represented by a rotary kiln as a medium,
Considering further stable production, the sintering temperature range was not sufficient with the above composition, and the sintering temperature range had to be further expanded.

Further, from the viewpoint of further reducing the production cost, it was necessary to lower the sintering start temperature.

Further, when considering use at a low temperature of 5 ° C. or less, more rapid hardening has been desired.

[0013]

Means for Solving the Problems The present invention is intended to solve St. such problems, means for solving the problems, as the mineral phase, 12CaO · 7Al ₂ O ₃ based calcium aluminate Clinker raw material mainly composed of
(However, excluding those with excessive lime saturation)
0.1 to 9% by weight of e ₂ O ₃ and 0.1 to 9% by weight of CaF ₂
Cold melt phase and the high temperature melt by Rukoto by wt% content coexist
And TiO ₂ in an amount of 0.5 to 9% by weight of the total
The addition allows the melting of the low-temperature melt phase and the high-temperature melt phase.
Rapid hardening crin produced by lowering the liquid formation start temperature and firing
Car composition .

Hereinafter, the hardened clinker composition of the present invention will be described in detail. The clinker raw material containing a C ₁₂ A _7- based calcium aluminate phase as a main component is a C ₁₂ A _7- based [11CaO · Al ₂ O ₃ · CaF ₂ (hereinafter abbreviated as C ₁₁ A ₇ · CaF ₂ ) as a mineral phase. Alone or C ₁₁
A ₇ · CaF ₂ and _C 12 mixture of _{A 7)} calcium aluminate 50 wt% or more, occupy preferably contains more than 65 wt%, and in all the calcium aluminate C
Proportion of ₁₂ A ₇ based calcium aluminate, is more than 50 wt%.

Here, the amount of calcium aluminate is 50
If it is less than wt%, the content of C ₁₂ A ₇ based calcium aluminate is steeper rigid component is reduced, because the rapid-hardening poor undesirably.

[0016] Accordingly, the C ₁₂ clinker raw materials composed mainly of A ₇ based calcium aluminate in rapid hardening clinker composition of the present invention, for the calcium aluminate amount of 50 wt% or more of course, sudden to enhance C ₁₂ a ₇ based calcium aluminate amount as possible from the viewpoint of securing of the rigid, it is preferable to ensure a calcium aluminate content 65% by weight or more.

In the calcium aluminate, 3CaO.Al ₂ O ₃ ,
_{CA, CaO · 2Al 2 O 3} , CaO · 6Al 2 O 3 may be various calcium aluminate coexist, such as, but from the viewpoint of ensuring rapid _hardening, the calcium aluminate _C 12 _{A 7} system, all It is preferable to secure 50% by weight or more based on the amount of calcium aluminate.

[0018] In the rapid hardening clinker composition of the present invention, such a _C 12 _{A 7} based clinker raw material whose main component is calcium aluminate, _Fe 2 _{O 3} the total 0.1 to 9 wt% , CaF ₂ in an amount of 0.1 to 9% by weight of the whole
It is contained coexist, and the whole TiO ₂ 0.5 to 9 wt%
It has been added.

Here, the addition amount of Fe ₂ O ₃ is set in the above range for the following reason.

If the amount is less than 0.1% by weight, the amount of the low-temperature melt phase generated is insufficient, and it is difficult to produce by a sintering method using a melt as a medium such as a rotary kiln.

On the other hand, if the content exceeds 9% by weight, the low-temperature melt phase is excessively increased, which makes it difficult to produce by a sintering method using the melt as a medium. Decrease.

The reason for setting the amount of CaF ₂ to the above range is as follows.

If the amount is less than 0.1% by weight, the temperature for generating the melt in the high-temperature melt phase is too high, and sintering does not proceed sufficiently.

On the other hand, if it exceeds 9% by weight, the difference in the temperature of the melt between the low-temperature melt phase and the high-temperature melt phase becomes small, and the amount of the generated melt phase cannot be controlled. In addition, the high-temperature melt phase is excessively increased, and it is difficult to manufacture the sintering method using the melt as a medium.

The reason why the addition amount of TiO ₂ is set in the above range is as follows.

If the amount is less than 0.5% by weight, the effect of adding TiO ₂ cannot be obtained.

On the other hand, if it exceeds 9% by weight, the amount of the rapidly hardened component is reduced, and the hardened hardness is reduced.

[0027]

According to clinker composition the present invention, when fired this to produce the _C 12 _{A 7} based calcium aluminate is a high temperature melt phase CaF ₂ reacts with CaO and _Al 2 _{O 3,} Fe ₂ O ₃ is also CaO and Al ₂ O ₃
Reacts with CaO-Al ₂ O ₃ -Fe to form a low-temperature melt phase
Generating a ₂ O ₃ based material. Further, Fe ₂ O ₃
By coexisting CaF ₂ and CaF ₂ , the difference in the melt generation temperature between the high-temperature melt phase and the low-temperature melt phase increases.

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 ₁₂ A
₇ series calcium aluminate does not dissolve and Ca
The temperature range in which _{O-Al 2 O 3 -Fe 2} O 3 based material is equivalent to the melt formation temperature difference of melting may be a sintering temperature.

Further, TiO ₂ acts on both the high-temperature melt phase and the low-temperature melt phase to lower the respective melt generation start temperatures and at the same time expand the melt generation temperature range.

Therefore, it is possible to sinter the clinker by a general sintering method using a rotary kiln or the like.

Further, the addition of TiO ₂ lowers the melting generation starting temperature, so that the clinker can be fired at a lower temperature.

Further, the amount of solid solution of TiO ₂ in the crystal increases, the rapid hardening of the clinker becomes good, and the strength also increases.

[0033]

Embodiments of the present invention will be described below.

A baking experiment was performed on the clinker compositions having the compositions shown in Tables 1, 2, 3 and 4.

[0035]

[Table 1]

[0036]

[Table 2]

[0037]

[Table 3]

[0038]

[Table 4]

The clinker composition adjusted to the target composition was compression-molded, heated to various temperatures in an electric furnace, kept for 1 hour, and rapidly cooled.

The external appearance of the obtained clinker was observed, and the temperature at which the clinker was melted was evaluated. At each firing temperature, sintering (*: no liquid phase is observed), a very small amount of melt (〇: a state in which the liquid phase is scattered and formed), and a melt generation (◎: Generated, clinker is densified), large amount of melt (●: large amount of liquid phase is generated), partially melted (◇: partially clinker is melted), completely melted (☆: the clinker molded product was completely melted and the original shape was not retained).

FIG. 1 is a graph showing the effect of TiO ₂ addition on the melt formation temperature of a clinker composition containing C ₁₂ A ₇ as a main component.

As is apparent from FIG. 1, in Comparative Examples 2 to 4 in which the amount of TiO ₂ added was 0.5% by weight or less, 120
There is no low temperature melt phase below 0 ° C. On the other hand, in Examples 1 to 9, a melt phase at 1200 ° C. or lower exists. In addition, it has been found that the melting temperature also decreases, and a high-temperature melt phase is easily formed from a low temperature.

Further, in Examples 1 to 9, the melt generation range was expanded as compared with Comparative Examples 2 to 4, so that the temperature difference from the generation of the clinker melt to the melting was 100 to 150.
It was able to expand to about ° C.

Accordingly, it was found from the clinker composition of this example that the clinker composition containing C ₁₂ A ₇ as a main component can be fired by a rotary kiln or the like.

FIG. 2 is a graph showing the effect of excessively adding or reducing Fe ₂ O ₃ to the clinker composition of Example 7 shown in Table 1.

As shown in FIG. 2, in Comparative Examples 5 to 7 in which the amount of TiO ₂ added was 0.5% by weight or less, the amount of the low-temperature melt phase was insufficient. The phases were present and the melting temperature was also reduced.

Further, in Examples 10 to 12, the melt generation range was expanded as compared with Comparative Examples 5 to 7.

FIG. 3 is a graph showing the effect of adding or reducing CaF ₂ to the clinker composition of Example 12 shown in Table 2.

FIG. 3 shows that Examples 13 to 1 were compared with Comparative Examples 8 to 10 in which the amount of TiO ₂ added was 0.5% by weight or less.
In No. 4, it was found that the melting temperature was lowered and a high-temperature melt phase was formed from a low temperature.

The clinker compositions having the compositions shown in Tables 1, 2, 3 and 4 were subjected to a comparative test of rapid hardening.
The comparative test of rapid hardening was performed by a proctor penetration resistance test according to the following procedure. The trial clinker synthesized by the firing method was pulverized to obtain a rapidly hardened clinker powder.
The cement used was ordinary Portland cement manufactured by Sumitomo Osaka Cement Co., and the sand used was quartz sand from Seto City, Ehime Prefecture.
The test temperature was 5 ° C.

Using these materials, the mortar was kneaded according to the mortar strength test method (JIS R 5201), allowed to stand for 30 minutes, and then added with a rapidly hardened clinker powder and kneaded for 30 seconds. This mortar was subjected to a proctor penetration resistance test. The proctor penetration resistance test was performed according to the concrete setting test method (JIS A 6204). The results are shown in Table 5, Table 6, Table 7, and Table 8.

[0052]

[Table 5]

[0053]

[Table 6]

[0054]

[Table 7]

[0055]

[Table 8]

As is evident from Tables 5, 6, 7 and 8, the rapidly hardening clinker composition of the present invention has a short time required for starting and ending, and has excellent rapid hardening at low temperatures. The characteristics were shown.

The clinker compositions having the compositions shown in Table 1, Table 2, Table 3, and Table 4 were fired at 1200 ° C. for 1 hour in an electric furnace, then rapidly cooled and pulverized. The mortar was kneaded in accordance with JIS R 5201 and allowed to stand for 30 minutes, after which a rapidly hardened clinker powder was added and kneaded for 30 seconds. This mortar was subjected to a mortar strength test. The cement used was ordinary Portland cement manufactured by Sumitomo Osaka Cement Co., and the sand used was quartz sand from Seto City, Ehime Prefecture. The test was performed at 5 ° C. Table 5, Table 6, Table 7, and Table 8 also show the results of the compressive strength test for the 28-year-old material.

As apparent from Tables 5, 6, 7 and 8, the clinkers of Examples 1 to 14 exhibited better strength development than those of Comparative Examples 1 to 12.

[0059]

As described above, when the hardened clinker composition of the present invention is calcined, CaF ₂ reacts with CaO and Al ₂ O ₃ to form a C ₁₂ A ₇ based high temperature melt phase. Of calcium aluminate, and Fe ₂ O ₃ similarly reacts with CaO and Al ₂ O ₃ to form a low-temperature melt phase Ca
_{O-Al 2} O 3 _-Fe to produce a 2 _{O 3} based material. Furthermore, the coexistence of Fe ₂ O ₃ and CaF ₂ in the raw material has the effect of increasing the difference in the temperature between the high-temperature melt phase and the low-temperature melt phase.

Accordingly, 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 ₁₂ A
₇ series calcium aluminate does not dissolve and Ca
There is an advantage that a temperature range corresponding to the above-mentioned difference in the temperature at which the O-Al ₂ O ₃ -Fe ₂ O ₃ -based substance is melted can be set as the sintering temperature.

Further, TiO ₂ acts on both the high-temperature melt phase and the low-temperature melt phase to lower the respective melt generation start temperatures, and at the same time, has the effect of expanding the melt generation temperature range.

Accordingly, there is an advantage that the production using a general rotary kiln or the like using the melt as a medium becomes easy.

In addition, the addition of TiO ₂ lowers the temperature at which the melt starts to be formed, so that there is an advantage that the clinker can be fired at a lower temperature.

Further, there is an effect that the amount of TiO ₂ dissolved in the crystal is increased, the rapid hardening of the clinker is improved, and the strength is increased.

The rapid-hardening clinker composition of the present invention exhibits excellent rapid-hardening properties not only at room temperature but also at low temperatures, and solves the problems of the conventional rapid-hardening clinker.

[Brief description of the drawings]

FIG. 1 is a graph showing the effect of adding TiO _{2 on} the melt generation temperature of a clinker of one example.

FIG. 2 is a graph showing the effect of adding TiO _{2 on} the melt generation temperature of the clinker of another example.

FIG. 3 is a graph showing the effect of adding TiO _{2 on} the melt generation temperature of the clinker of another example.

──────────────────────────────────────────────────続 き Continuing from the front page (72) Nobuaki Shiokawa 7-55 Minamienkajima, Taisho-ku, Osaka City Sumitomo Osaka Cement Co., Ltd. Central Research Laboratory Cement and Concrete Research Laboratory (72) Inventor Yoshiyuki Kumekawa Osaka City 7-55 Minamienkajima Taisho-ku Sumitomo Osaka Cement Co., Ltd. Central Research Laboratory Cement and Concrete Research Laboratory (56) References JP-A-48-12324 (JP, A) JP-A-6-115983 (JP, A) (58) Fields surveyed (Int. Cl. ⁷ , DB name) C04B ^7/ 00-7/60

Claims (3)

(57) [Claims] 1. A clinker composition for use in a quick-setting cement, a quick-setting material, a quick-setting cement, a ground improvement material, a masking material, and the like, wherein 12CaO · 7Al is used as a mineral phase.
The clinker raw material mainly composed of ₂ O ₃ based calcium aluminate, 0.1 to 9% by weight of the total of Fe ₂ O _3, CaF ₂
Cold by Rukoto to total 0.1 to 9 wt% containing coexistence
To produce a melt phase and hot melt phase, and high and low YutakaToru liquid phase by the TiO ₂ is added 0.5 to 9 wt% of the total
Rapid hardening clinker composition lowers the melt generation starting temperature of the YutakaToru liquid phases characterized by being fired. 2. The method according to claim 1, wherein the TiO ₂ is contained in the entire clinker raw material.
2. The rapidly hardening clinker composition according to claim 1, which is added in an amount of 1.0 to 7.0% by weight. 3. The method according to claim 1, wherein the TiO ₂ is contained in the entire clinker raw material.
The rapidly hardening clinker composition according to claim 1, which is added in an amount of 1.2 to 5.0% by weight.