JP4585328B2 - Solidifying material composition - Google Patents

Description

  The present invention relates to a solidified material composition that effectively uses chlorine bypass dust recovered in a cement manufacturing plant equipped with a chlorine bypass device.

  Conventionally, a method of using chlorine bypass dust recovered in a cement manufacturing plant equipped with a chlorine bypass device as a solidified material has been studied.

  For example, like the cement raw material firing apparatus shown in Patent Document 1, after extracting a part of the exhaust gas in the cement kiln with a chlorine bypass device, volatile components such as alkali chloride contained in the exhaust gas are solidified outside the system. There is a technique for reducing the amount of alkali chloride and the like in the cement raw material firing system by processing. This chlorine bypass device is additionally installed in the cement kiln for the purpose of preventing coating troubles in the cement raw material firing system and extracting chlorine and the like in the cement clinker.

  The gas component extracted by the chlorine bypass device is returned to the cement raw material system again through the dust collector or released into the atmosphere. Solid materials composed of calcined cement raw materials and sulfates thereof are generated. This solid matter is called chlorine bypass dust, and may be made sludge or the like by reducing the basicity by washing with water.

Patent Document 2 discloses a cement composition comprising 90% by mass to 99.7% by mass of cement containing blast furnace slag or fly ash and 0.3% by mass to 10% by mass of chlorine bypass dust and a method for producing the same. ing. According to this production method, by mixing chlorine bypass dust, there is an effect of increasing the initial strength of 3 days and 7 days of age, and there is no decrease in the strength of 28 days of age, which is a drawback of the initial strength improver. It has been shown.
Japanese Patent Laid-Open No. 10-330136 JP-A-10-218657

  As a part of effective utilization of chlorine bypass dust, the present inventors are proceeding with development of a solidifying material composition to which chlorine bypass dust is added. In this field, there is a demand for a solidified material composition that contains chlorine bypass dust and has a strength development equal to or higher than that of a solidified material composition that does not use chlorine bypass dust. However, the above-mentioned document does not disclose any solidifying material composition using chlorine bypass dust.

  Then, an object of this invention is to provide the solidification material composition excellent in intensity | strength expression using the chlorine bypass dust.

  As a result of earnestly studying the influence of the chlorine content, the blast furnace slag content, and the Blaine specific surface area on the strength development of the solidified material composition in the solidified material composition, When it was within the range, it was found that a solidified material composition excellent in strength development was obtained, and the present invention was completed.

The solidifying material composition according to the present invention is a solidifying material composition comprising a cement clinker, blast furnace slag, and chlorine bypass dust containing chlorine as composition components. The relationship between the chlorine content X mass% in the solidified material composition, the blast furnace slag content Y mass% in the solidified material composition, and the Blaine specific surface area Zcm ² / g of the solidified material composition is expressed by the formula (1). the satisfaction of the.
0 <Y ≦ −4.375X + 38.75 or 583X + 2834 ≦ Z ≦ 6000 (1)

Here, in the solidified material composition, the chlorine content X mass% in the solidified material composition, the blast furnace slag content Y mass% in the solidified material composition, and the Blaine specific surface area Zcm ² / g of the solidified material composition. It is preferable that the relationship between and further satisfies the formula (2) or the formula (3).
In the case of 0 <X ≦ 2, 0 <Y ≦ 30, or 4000 ≦ Z ≦ 6000 (2)
In the case of 2 ≦ X, 0 <Y ≦ −4.375X + 38.75, or 583X + 2834 ≦ Z ≦ 6000 (3)

  According to the solidifying material composition of the present invention, it is possible to obtain a solidifying material composition excellent in strength development by using chlorine bypass dust.

  Hereinafter, preferred embodiments of the cement-based solidifying material composition according to the present invention will be described in detail.

  The solidifying material composition according to the present invention includes cement clinker, blast furnace slag, gypsum, and chlorine bypass dust.

  Examples of the cement clinker include ordinary Portland cement clinker and early-strength Portland cement clinker.

The blast furnace slag is not particularly limited, but is preferably rapidly crushed. The basicity of the blast furnace slag is preferably 1.4 or more. Here, the basicity is calculated by dividing the total amount of CaO content, MgO content, and Al ₂ O ₅ content by the amount of SiO ₂ . These contents are measured according to JIS R 5202 “Chemical analysis method of Portland cement”.

  Examples of gypsum include natural gypsum, drainage gypsum, hydrofluoric gypsum, and the like, and these gypsum forms may be any of dihydrate gypsum, hemihydrate gypsum, and anhydrous gypsum. Moreover, as for content in the solidification material composition of the gypsum represented with content of sulfur trioxide, 6 mass%-15 mass% are especially preferable. If it is out of this range, the strength developability is lowered, and if it is too much, the solidified soil tends to be expanded and broken.

  Chlorine bypass dust is a solid material composed of chlorides such as KCl, calcined cement raw materials, sulfates thereof, and the like. This solidifying material composition is obtained from a chlorine bypass device that extracts a part of the exhaust gas in the cement kiln. The chlorine bypass dust used in the solidifying material composition may be a solid before being washed with water, or may be sludge or the like that has been washed with water to reduce the chlorine concentration.

  The solidifying material composition can further contain inorganic components other than the blast furnace slag as a mixture, and examples thereof include fly ash, limestone, and silica fume. The blending amount of the mixed material is determined from the chlorine content in the solidifying material composition. Chlorine is derived from chlorine bypass dust. The chlorine content in the solidifying material composition is measured according to JIS R 5202 “Chemical analysis method for Portland cement”.

Then, the solidified material composition according to the present embodiment includes a chlorine content X wt% in solidifying material composition, and blast furnace slag content Y wt% in solidifying material composition, Blaine specific surface area ZCM ² of solidified material composition / g satisfies the relationship of the formula (1).
0 <Y ≦ −4.375X + 38.75 or 583X + 2834 ≦ Z ≦ 6000 (1)

When the chlorine content X mass%, the blast furnace slag content Y mass%, and the Blaine specific surface area Zcm ² / g satisfy the formula (1), the uniaxial compressive strength of the soil solidified using the solidified material composition Is sufficiently secured. Here, the Blaine specific surface area is measured according to JIS R 5201 “Physical Test Method for Cement”.

Here, the solidified material composition according to the present embodiment includes a chlorine content X mass% in the solidified material composition, a blast furnace slag content Y mass% in the solidified material composition, and a brain specific surface area Zcm of the solidified material composition. It is preferable that ² / g further satisfies the relationship of the formula (2) or the formula (3).
In the case of 0 <X ≦ 2, 0 <Y ≦ 30 or 4000 ≦ Z ≦ 6000 (2)
In the case of 2 ≦ X, 0 <Y ≦ −4.375X + 38.75, or 583X + 2834 ≦ Z ≦ 6000 (3)

When the blast furnace slag content Y is 0 <Y ≦ 30, not only solid soil is solidified but also soft soil such as highly organic soil is solidified. Also, excellent strength development of the solidified material Blaine specific surface area Z is 4000 cm ² / g or more, Blaine specific surface area can be suppressed manufacturing cost of the solidifying material composition is less than 6000 cm ² / g.

Such a solidifying material composition can be produced, for example, by mixing and grinding cement clinker, blast furnace slag, gypsum, and chlorine bypass dust. Here, the compounding amount of each material is the chlorine content X mass% in the solidified composition after mixing, the blast furnace slag content Y mass% in the solidified composition, and the Blaine specific surface area Zcm ² of the solidified composition. For example, the composition of each material is measured and set according to this measured value so that / g satisfies the formula (1), or the combination of the formula ( 2 ) or the formula ( 3 ), or by trial and error. You can set it.

  The order of mixing the respective materials is arbitrary. For example, after mixing cement clinker and chlorine bypass dust in advance, blast furnace slag or the like may be added to the mixture later, and materials other than chlorine bypass dust may be added in advance. After mixing, chlorine bypass dust may be mixed with this mixture. In addition, it is preferable to perform manufacture of the solidification material composition which concerns on this invention using chlorine bypass dust in the cement manufacturing plant provided with the chlorine bypass apparatus.

The solidifying material composition of the present invention can be used in the same manner as a general solidifying material. That is, what is necessary is just to mix this solidification material composition, process target soil, and the quantity of water as needed. The amount of the solidifying material composition mixed with the soil to be treated naturally varies depending on the water content ratio, soil quality, organic matter content, and the like of the target soil. For example, the required amount of the solidifying material composition per 1 m ^{3 of} the target soil is usually 50 to 200 kg for sandy soil, 50 to 300 kg for clay soil, and 100 to 500 kg for highly hydrous soil or highly organic soil. Select and use within a range.

  In addition, when improving the soft soil using the solidifying material composition, a dry method in which the solidifying material composition is mixed with the target soil as a powder, the solidifying material composition and water are mixed in advance to form a slurry. However, the solidifying material composition of the present invention can be used in any method.

  Hereinafter, the content of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

  Here, various solidifying material compositions were prepared by adding chlorine bypass dust to various cement-based solidifying materials mixed in advance.

[Materials used]
The materials used are shown below.
(1) Cement-based solidifying materials A to H
A cement-based solidified material was manufactured by mixing early strong Portland cement clinker, waste gypsum and blast furnace slag manufactured by Ube Industries, Ltd. at a predetermined ratio and pulverizing with a finishing mill. Table 1 shows the production conditions for the cement-based solidified material. As shown in Table 1, 8 types of cementitious solidified materials A to H were produced.

Here, as the early strong Portland cement clinker, a C ₃ S mineral composition amount of 69% was used. The C ₃ S mineral composition amount of the early strong Portland cement clinker was obtained by measuring the chemical component according to JIS R 5202 “Method for chemical analysis of Portland cement” and by the following Borg equation.
C ₃ S content = 4.071 × CaO amount -7.600 × SiO ₂ amount -6.718 × _Al 2 _{O 3} amount
−1.430 × Fe ₂ O ₃ amount−2.852 × SO ₃ amount

  The chemical composition of gypsum was measured according to JIS R 9101 “Analytical method of gypsum”, and the chemical composition of blast furnace slag was measured according to JIS R 5202 “Chemical analysis method of Portland cement”.

Next, Table 2 shows chemical components of gypsum and blast furnace slag mixed with early-strength Portland cement clinker.

(2) Chlorine bypass dust As the chlorine bypass dust mixed with the cement-based solidifying materials A to H, two types a and b having different chlorine contents were used. Table 3 shows chemical components of the chlorine bypass dusts a and b. The chemical components excluding the chlorine content of the chlorine bypass dust were measured according to JIS R 8853 “Chemical analysis method of aluminosilicate materials for ceramics”. The chlorine content was measured according to JIS R 5202 “Chemical analysis method for Portland cement”.

[Preparation of solidifying material composition]
To any of the cement solidifying material A to H, chlorine bypass dust a, and any of b is added a predetermined ratio, the reference example chlorine content X, blast furnace slag content Y, a combination of Blaine specific surface area Z different Solidified material compositions of 1 to 7 and Examples 1 to 5 were produced. Here, in Reference Examples 1 to 7 and Examples 1 to 5 , the relationship among the chlorine content X, the blast furnace slag content Y, and the Blaine specific surface area Z satisfies the above formula (1), and further, the formula (2) or The combination of formula (3) is also satisfied. Table 4 shows the sulfur trioxide content, chlorine content X, blast furnace slag content Y, and brain specific surface area Z of the solidified material compositions of Reference Examples 1 to 7 and Examples 1 to 5 .
Further, as Comparative Example 1, a solidified material composition containing no chlorine bypass dust, that is, having a chlorine content of 0 was produced as Comparative Example 1. Furthermore, solidified material compositions that contained chlorine bypass dust but did not satisfy Formula (1), and further did not satisfy the combination of Formula (2) or Formula (3) were produced as Comparative Examples 2-7. . Table 4 shows the sulfur trioxide content, chlorine content X, blast furnace slag content Y, and Blaine specific surface area Z of the solidified material compositions of Comparative Examples 1 to 7.

[Soil solidification test and its evaluation]
When the black soil as the target soil having a water content ratio of 93.6% by mass and a wet density of 1.425 g / cm ³ was mixed with each solidifying material composition prepared by the above method at 200 kg / m ³ , the curing period was 7 days. The uniaxial compressive strength was measured. Here, the water content ratio of the target soil was measured according to JIS A 1203 “Method for testing water content of soil”, and the wet density was measured according to JIS A 1202 “Method for testing density of soil particles”. In addition, the uniaxial compressive strength was obtained by mixing a target soil and a predetermined amount of a solidifying material composition and kneading for 5 minutes with a Hobart mixer to prepare a specimen having a diameter of 5 cm and a length of 10 cm. The specimen was hermetically sealed at 20 ° C. for 7 days, and then the uniaxial compressive strength was measured according to JIS A 1216 “Soil Uniaxial Compression Test Method”. The results are shown in Table 4.
Moreover, about the uniaxial compressive strength, on the basis of the comparative example 1 whose chlorine content is 0.00 mass%, the ratio (percentage) of the change of the uniaxial compressive strength with respect to the uniaxial compressive strength of the reference is shown in each example and reference. Examples and comparative examples are shown. Then, the case where the uniaxial compression strength change ratio was 95% or more was judged as good (O), and the case where the uniaxial compression strength change ratio was less than 95% was judged as poor (X).
Further, by adjusting the water / solidification agent composition ratio of 60% slurry, using coaxial double cylinder rotational viscometer (Haake Co. Rotovisco RV1), shear stress at a shear rate (gamma ₁₀₀₎ is 100s ^-1 (τ ₁₀₀ ) was measured, and the apparent viscosity (η _a ) was calculated from the following equation.
η _a = τ ₁₀₀ / γ ₁₀₀
The measurement of the shear stress (τ ₁₀₀ ) was 15 minutes after adjusting the slurry, and the slurry temperature was set to 35 ° C.

Based on the determination results in Table 4, the relation between the chlorine content X wt% and blast furnace slag content Y wt% when the Blaine specific surface area Z is 4000 cm 2 / ^g in FIG. 1, blast furnace slag content Y is 30 FIG. 2 shows the relationship between the chlorine content X mass% and the Blaine specific surface area Zcm ² / g when the mass%.

According to the present example , reference example and comparative example, for example, as in reference examples 1 to 3, 5 to 7 and examples 2 and 5 in FIG. 1 and FIG. ) Or the combination of formula (3), it was found that the uniaxial compressive strength change ratio was 95% or more.
Further, within the range of the formula (1), or the combination of the formula (2) or the formula (3), the fluidity of the slurry of the solidifying material composition showed fluidity that was not a problem in practice.

  According to the present invention, since the solidified material composition having excellent strength development using chlorine bypass dust is realized, the use of chlorine bypass dust can be expanded.

FIG. 1 is a graph showing the relationship between the amount of chlorine, the amount of blast furnace slag, and the determination result of the uniaxial compressive strength test when the specific surface area of the brain is 4000 cm ² / g. FIG. 2 is a graph showing the relationship between the chlorine content, the Blaine specific surface area, and the determination result of the uniaxial compressive strength test when the blast furnace slag amount is 30% by mass.

Claims (6)

A solidifying material composition comprising a cement clinker, a blast furnace slag, and chlorine bypass dust containing chlorine,
The solidified material composition in which the chlorine content X mass% in the solidified material composition and the blast furnace slag content Y mass% in the solidified material composition satisfy the following formulas (A) to (C) .
0 <Y ≦ −4.375X + 38.7 5 ( A )
3.43 ≦ X ≦ 5.14 (B)
15 ≦ Y ≦ 20 (C)   A solidifying material composition comprising a cement clinker, a blast furnace slag, and chlorine bypass dust containing chlorine,
  The chlorine content X mass% in the solidified material composition and the Blaine specific surface area Zcm of the solidified material composition ² / G satisfies the following formulas (D) to (F).
  583X + 2834 ≦ Z ≦ 6000 (D)
  3.43 ≦ X ≦ 5.14 (E)
  5000 ≦ Z ≦ 6000 (F)   A solidified material composition comprising a cement clinker, blast furnace slag, and chlorine bypass dust containing chlorine as a component, high organic soil 1 m ³ A method for improving soft soil by mixing 100 kg to 500 kg per unit,
  A method in which the chlorine content X mass% in the solidified material composition and the blast furnace slag content Y mass% in the solidified material composition satisfy the following formulas (A) to (C).
  0 <Y ≦ −4.375X + 38.75 (A)
  3.43 ≦ X ≦ 5.14 (B)
  15 ≦ Y ≦ 20 (C)   A solidified material composition comprising a cement clinker, blast furnace slag, and chlorine bypass dust containing chlorine as a component, high organic soil 1 m ³ A method for improving soft soil by mixing 100 kg to 500 kg per unit,
  The chlorine content X mass% in the solidified material composition and the Blaine specific surface area Zcm of the solidified material composition ² / G satisfies the following formulas (D) to (F).
  583X + 2834 ≦ Z ≦ 6000 (D)
  3.43 ≦ X ≦ 5.14 (E)
  5000 ≦ Z ≦ 6000 (F)   Cement clinker, blast furnace slag, and chlorine bypass dust containing chlorine are mixed and pulverized to produce a solidified material composition containing the cement clinker, the blast furnace slag, and the chlorine bypass dust as composition components. A method,
  Production of solidified material composition, wherein the chlorine content X mass% in the solidified material composition and the blast furnace slag content Y mass% in the solidified material composition satisfy the following formulas (A) to (C). Method.
  0 <Y ≦ −4.375X + 38.75 (A)
  3.43 ≦ X ≦ 5.14 (B)
  15 ≦ Y ≦ 20 (C)   Cement clinker, blast furnace slag, and chlorine bypass dust containing chlorine are mixed and pulverized to produce a solidified material composition containing the cement clinker, the blast furnace slag, and the chlorine bypass dust as composition components. A method,
  The chlorine content X mass% in the solidified material composition and the Blaine specific surface area Zcm of the solidified material composition ² / G satisfies the following formulas (D) to (F).
  583X + 2834 ≦ Z ≦ 6000 (D)
  3.43 ≦ X ≦ 5.14 (E)
  5000 ≦ Z ≦ 6000 (F)

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