JP6563742B2 - Irwin hydraulic composition and method for producing the same - Google Patents

Description

  The present invention relates to an Irwin hydraulic composition that can be used for a long period of time and can be easily extended by using a small amount of a set retarder.

Irwin based hydraulic composition, as a main component, Irwin _{(3CaO · 3Al 2 O 3 ·} CaSO 4), belite (2CaO · _SiO 2), a ferrite phase _{(4CaO · Al 2 O 3 ·} Fe 2 O 3), And anhydrous gypsum (CaSO ₄ ), which is excellent in rapid hardening and low alkalinity. Taking advantage of these features, Irwin hydraulic compositions include GRC (Glass Fiber Reinforced Concrete) cement, cement for radioactive waste solidification, solidified material for ground improvement of highly organic soil soft ground such as peat, etc. Is used.
In addition, the clinker of the Irwin hydraulic composition is attracting attention as an energy-saving cement clinker because it has a lower firing temperature and limestone basic unit than the Portland cement clinker and consumes less energy for firing the clinker.

  However, since Irwin has a high hydration activity, mortar and concrete using an Irwin hydraulic composition have a problem that it is difficult to ensure and adjust the pot life. That is, in order to adjust the setting of concrete or the like, a setting retarder is usually used, but generally used polymers such as oxycarboxylic acids such as gluconic acid, citric acid and tartaric acid, lignin sulfonic acid and humic acid are used. Setting delays such as organic acids, magnesium silicofluoride, and inorganic acids such as boric acid are not only effective against Irwin hydraulic compositions, but also have a strong effect depending on the type of setting retarder. The expression may be greatly reduced. For example, citric acid, which is frequently used as a setting retarder, shortens the setting time depending on the amount added.

  Therefore, a setting retarding method and a setting retarding agent for an Irwin hydraulic composition have been developed. For example, the setting delay method described in Patent Document 1 is a method in which 0.1 to 5 parts by weight of aldonic acid and / or a salt thereof as a setting retarder is added to 100 parts by weight of the Irwin hydraulic composition. . Moreover, the setting retarder described in Patent Document 2 includes at least one first component selected from citric acid and a salt thereof, and at least one second component selected from heptonic acid and a salt thereof. A setting retarder, 0.01 to 3.0 parts by weight of the first component with respect to 100 parts by weight of the Irwin hydraulic composition, and 40 to 150 parts by weight of the second component with respect to 100 parts by weight of the first component. It is a set retarder added in part. However, these setting retarders are useful but expensive, and this high cost is one of the factors that hinder the spread of Irwin hydraulic compositions.

JP 09-255388 A JP 09-295842 A

  Therefore, an object of the present invention is to provide an Irwin hydraulic composition that has a long pot life and can easily extend the pot life by using a small amount of a set retarder.

  As a result of intensive studies to achieve the above object, the present inventor found that an Irwin hydraulic composition containing an Irwin clinker containing a specific amount of phosphorus can achieve the above object, and has completed the present invention. . That is, this invention is the Irwin hydraulic composition which has the following structures, and its manufacturing method.

[1] Portland cement clinker powder 80 to 150 parts by mass and anhydrous gypsum powder 20 to 50 with respect to 100 parts by mass of phosphorus-containing Irwin clinker powder containing 0.25 to 2.0% by mass of phosphorus in terms of P ₂ O ₅ An Irwin hydraulic composition containing at least a part by mass.
[2] The phosphorus-containing erwin clinker includes at least 40 to 80% by mass of erwin (3CaO · 3Al ₂ O ₃ · CaSO ₄ ) and 10 to 40% by mass of belite (2CaO · SiO ₂ ). An Irwin hydraulic composition as described in any of the above.
[3] The Irwin hydraulic composition according to the above [1] or [2] , wherein the Portland cement clinker powder is an early Portland cement clinker powder or a normal Portland cement clinker powder.
[4] One or more setting retarders selected from citric acid, heptonic acid, succinic acid, tartaric acid, and salts thereof are used as the Irwin hydraulic composition according to any one of [1] to [ 3 ]. An Irwin hydraulic composition containing a setting retarder, containing 0.5 parts by mass or less per 100 parts by mass of the product.
[5] One or more setting accelerators selected from lithium carbonate, calcium nitrite, and calcium lactate are added to 100 parts by mass of the Irwin hydraulic composition according to any one of [1] to [ 4 ]. An Irwin hydraulic composition containing a setting accelerator containing 5 parts by mass or less.
[6] As the phosphorus raw material of the phosphorus-containing Irwin clinker, using at least one selected from metal-containing sludges, sewage sludge, and livestock waste (livestock excrement), the above-mentioned [1] to [ 5 ] The manufacturing method of the Irwin hydraulic composition which manufactures the Irwin hydraulic composition in any one.

  The Irwin hydraulic composition of the present invention has a long pot life, and the pot life can be easily extended by using a small amount of a set retarder.

It is a graph which shows the compressive strength of the mortar containing an Irwin hydraulic composition.

As described above, the present invention includes an Irwin hydraulic composition containing at least 80 to 150 parts by mass of Portland cement clinker powder and 20 to 50 parts by mass of anhydrous gypsum powder with respect to 100 parts by mass of phosphorus-containing Irwin clinker powder. It is.
Hereinafter, the present invention is divided into the constituent components of the Irwin hydraulic composition, the phosphorus-containing Irwin clinker powder, the Portland cement clinker powder, the anhydrous gypsum powder and the like, and the manufacturing method of the Irwin hydraulic composition. Explained.

1. Phosphorus-containing Irwin clinker powder The phosphorus-containing Irwin clinker powder contains 0.25 to 2.0% by mass of phosphorus in terms of P ₂ O ₅ . If the phosphorus content is less than 0.25% by mass, the effect of extending the pot life of the Irwin hydraulic composition is reduced, and if it exceeds 2.0% by mass, the strength expression of the Irwin hydraulic composition is reduced. To do. In addition, the phosphorus content is preferably 0.3 to 2.0% by mass, more preferably 0.45 to 2.0% by mass, and still more preferably 0.6 to 1.8% in terms of P ₂ O _5. % By mass.
Also, the phosphorus-containing Irwin system clinker, Irwin _{(3CaO · 3Al 2 O 3 ·} CaSO 4) 40~80 % by weight, and belite (2CaO _· SiO 2) comprises at least 10 to 40 wt%. When the Erwin content is less than 40% by mass, the rapid hardening of the Irwin hydraulic composition is reduced, and when it exceeds 80% by mass, the long-term strength development of the Irwin hydraulic composition is reduced. Further, if the belite is less than 10% by mass, the long-term strength developability of the Erwin hydraulic composition is lowered, and if it exceeds 40% by mass, the rapid hardness of the Erwin hydraulic composition is lowered.
Further, the phosphorus-containing Irwin clinker is composed of an aluminate phase (3CaO · Al ₂ O ₃ ) of 7% by mass or less, a ferrite phase (4CaO · Al ₂ O ₃ · Fe ₂ O ₃ ) of 3 to 20% by mass, anhydrous gypsum ( CaSO ₄₎ may contain 0.1 to 10 mass%. By including these components, it is easy to adjust the pot life of the Irwin hydraulic composition, and the energy consumed for firing the Irwin clinker can be reduced without reducing the strength development.

2. Portland cement clinker powder In the present invention, as the Portland cement clinker powder, any of early strong Portland cement clinker powder, ordinary Portland cement clinker powder, moderately heated Portland cement clinker powder, and low heat Portland cement clinker powder can be used. From the viewpoint of the strength development of the hydraulic composition, an early strong Portland cement clinker powder or a normal Portland cement clinker powder is preferable.
The mixing ratio of the Portland cement clinker powder is 80 to 150 parts by mass of the Portland cement clinker powder with respect to 100 parts by mass of the phosphorus-containing Irwin clinker powder. If the mixing ratio is less than 80 parts by mass, the long-term strength development of the Irwin hydraulic composition may be reduced, and if it exceeds 150 parts by mass, the early strength development of the Irwin hydraulic composition may be reduced. is there. The Portland cement clinker powder is preferably 90 to 140 parts by mass, more preferably 100 to 130 parts by mass with respect to 100 parts by mass of the phosphorus-containing Irwin clinker powder.

3. Anhydrous gypsum powder The anhydrous gypsum powder is preferably type II anhydrous gypsum from the viewpoint of strength development, and its specific surface area of brane is preferably 2500-12000 cm ² / g, more preferably 3500-8000 cm ² / g, Preferably it is 3700-5000 cm < ² > / g.
Here, if all of the anhydrous gypsum is fine, cracks and warpage due to expansion of the cured hydraulic composition are likely to occur, and therefore some anhydrous gypsum is preferably coarse. In this case, in 100% by mass of anhydrous gypsum powder, the content of fine particles preferably having a Blaine specific surface area of 4500 to 12000 cm ² / g is 50 to 80% by mass, and the Blaine specific surface area is 2500 to 4000 cm ² / g. The content of coarse particles is 20 to 50% by mass.
In the production of an Erwin hydraulic composition, two types of anhydrous gypsum having different Blaine specific surface areas can be mixed in a predetermined amount. As will be described later, a part of the anhydrous gypsum (coarse product) is part of the Irwin clinker. A method of simultaneously pulverizing and pulverizing at the time of pulverization and post-adding the remainder is simple and preferable.
Moreover, the mixing ratio of the anhydrous gypsum powder in the Erwin hydraulic composition is 20 to 50 parts by mass with respect to 100 parts by mass of the phosphorus-containing Irwin clinker powder. If the content of the anhydrous gypsum powder is out of the range, the long-term strength development of the Irwin hydraulic composition may be reduced. The content ratio of the anhydrous gypsum powder is preferably 25 to 45 parts by mass with respect to 100 parts by mass of the phosphorus-containing Irwin clinker powder.
The molar ratio of SO ₃ / Al ₂ O _{3 in} the Erwin hydraulic composition is preferably 1.0 to 1.5, more preferably 1.05, from the viewpoint of ensuring pot life and strength development. 1.3. However, the molecular SO ₃ is the total amount of SO ₃ contained in both the phosphorus-containing Irwin clinker and the anhydrous gypsum powder.

4. Setting retarder The present invention further provides one or more setting retarders selected from citric acid, heptonic acid, succinic acid, tartaric acid, and salts thereof for the purpose of adjusting the pot life. You may contain 0.5 mass part or less with respect to 100 mass parts of hydraulic compositions. When the content rate of a setting retarder exceeds 0.5 mass part, there exists a possibility that the intensity | strength development property of an Irwin hydraulic composition may fall. The content of the setting retarder is preferably 0.01 to 0.45 parts by mass, more preferably 0.05 to 0.4 parts by mass, and still more preferably 100 parts by mass of the Irwin hydraulic composition. Is 0.1 to 0.35 parts by mass.
In addition, the particle size of the setting retarder is preferably 0.1 μm to 10 mm, more preferably 1 μm to 5 mm, and still more preferably 3 μm to 3 mm, from the viewpoint of expression of the retarding effect of the setting retarder.

5. The setting accelerator further enhances early strength development by using a setting accelerator selected from i) lithium carbonate, ii) a mixture of lithium carbonate and calcium nitrite, or iii) a mixture of lithium carbonate and calcium lactate. Therefore, 5 parts by mass or less may be included with respect to 100 parts by mass of the Irwin hydraulic composition. If it exceeds 5 parts by mass, the long-term strength development of the Irwin hydraulic composition may be reduced. The content ratio of the setting accelerator is preferably 0.1 to 4.5 parts by mass, more preferably 0.5 to 4 parts by mass, and still more preferably 1 with respect to 100 parts by mass of the Irwin hydraulic composition. -3.5 parts by mass.
From the viewpoint of strength development,
ii) The mixing ratio (mass ratio) of the mixture of lithium carbonate and calcium nitrite is preferably lithium carbonate: calcium nitrite = 50: 50 to 15:85, more preferably 40:60 to 20:80. is there. Also,
iii) The mixing ratio (mass ratio) of the mixture of lithium carbonate and calcium lactate is preferably lithium carbonate: calcium lactate = 50: 50 to 15:85, more preferably 40:60 to 20:80.
The particle size of the setting accelerator is preferably 0.1 μm to 10 mm, more preferably 1 μm to 5 mm, and still more preferably 3 μm to 3 mm, from the viewpoint of expression of the acceleration effect of the setting accelerator.

The brane specific surface area of the Irwin hydraulic composition of the present invention is preferably 4000 to 5000 cm ² / g from the viewpoint of early and long-term strength development. The Blaine specific surface area of the phosphorus-containing Irwin clinker powder and Portland cement clinker powder is also preferably within this range.

5. Manufacturing method of Erwin hydraulic composition The manufacturing method of the Irwin hydraulic composition of the present invention includes the following (a) to (d) pulverization after manufacturing the phosphorus-containing Irwin clinker of (A) below. -Any one of the mixing methods may be used. That is,
(A) The phosphorus source used in the production of the phosphorus-containing Irwin clinker is not particularly limited as long as it is contained in the raw material and / or fuel. For example, sludge containing metal such as aluminum sludge, sewage sludge, Examples include livestock waste (livestock manure). Among these, the use of sewage sludge is preferable from the viewpoint of building a resource recycling society.
In addition, for firing the phosphorus-containing Irwin clinker, a normal firing furnace such as a rotary kiln used for firing Portland cement clinker can be used, and the firing temperature (maximum temperature) is 1250 to 1350 ° C. is there. If the firing temperature is less than 1250 ° C., the degree of firing of the clinker is insufficient, and if the firing temperature exceeds 1350 ° C., the main quality characteristics such as coagulation and strength development may be deteriorated.
And, using the phosphorus-containing Irwin clinker obtained in the step (A),
(A) A method of pulverizing phosphorus-containing Irwin clinker, Portland cement clinker, and anhydrous gypsum until the Blaine specific surface area of the whole powder becomes 4000 to 5000 cm ² / g,
(B) After pulverizing phosphorus-containing Irwin clinker, Portland cement clinker, and part of anhydrous gypsum (50 to 80% by mass of anhydrous gypsum is preferred) until the Blaine specific surface area becomes 4000 to 5000 cm ² / g. , A method of mixing the remaining anhydrous gypsum into the pulverized product,
(C) pulverization with phosphorus-containing Erwin clinker and part of anhydrous gypsum (preferably 50 to 80% by mass of anhydrous gypsum) having a Blaine specific surface area of 4000 to 5000 cm ² / g, Portland cement clinker, and the rest A method of mixing these two types of clinker pulverized materials after separately grinding the anhydrous gypsum of the above to a Blaine specific surface area of 3000 to 5000 cm ² / g,
(D) Grinding with phosphorus-containing Irwin clinker and part of anhydrous gypsum (preferably 50 to 80% by mass of anhydrous gypsum) having a Blaine specific surface area of 4000 to 5000 cm ² / g; Is a method of mixing these two types of clinker pulverized product and the remaining anhydrous gypsum after separately performing pulverization of 3000 to 5000 cm ² / g,
Any one of the pulverization and mixing methods is adopted.
The setting retarder and the setting accelerator may be pulverized at the same time in any of the clinker pulverization steps if pulverization is necessary, and clinker pulverization if the pulverization agent has a sufficiently fine particle size. What is necessary is just to add a predetermined amount to a thing.
Among the pulverization / mixing methods described above, the method (a) is completed with only one pulverization step, so that an Irwin hydraulic composition can be easily produced. On the other hand, since the methods (b) to (d) include two types of anhydrous gypsum having different brain specific surface areas, it is possible to produce an Irwin hydraulic composition that is particularly excellent in early strength development at low temperatures.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples.
1. Preparation of phosphorus-containing erwin clinker
Type II anhydrous gypsum, bauxite, limestone, and calcium hydrogen phosphate dihydrate (reagent grade, manufactured by Kanto Chemical Co., Inc.) are mixed and compacted so as to have the chemical composition shown in CP1 to 5 in Table 1, and pelletized Was made. Next, the pellet was placed in an ultra-high temperature heating electric furnace, held at 1000 ° C. for 30 minutes to perform dehydration and decarboxylation, and then heated to 1350 ° C. at a heating rate of 700 ° C./hour. Baked at 20 ° C. for 20 minutes. Then, it stood to cool outside a furnace and produced the clinker which has a mineral composition shown to CP1-5 of Table 2.
For comparison, a mineral type II anhydrous gypsum, bauxite, and limestone are mixed and consolidated so as to have a chemical composition shown in CN1 in Table 1, and the minerals shown in CN1 in Table 2 in the same manner as CP1-5. A clinker having a composition was made.

2. Production of Erwin hydraulic composition An Erwin hydraulic composition was produced by the method (b) using the CP1-5 and CN1 Erwin clinker and the materials shown in Table 3. Specifically, Irwin clinker, Portland cement clinker, anhydrous gypsum (74% by mass of the total anhydrous gypsum to be added), and lithium carbonate (aggregation accelerator) are pulverized according to the formulation shown in the column of “Crushing” in Table 4. After that, according to the composition shown in the “mixing” column of Table 4, the remaining anhydrous gypsum (26 mass% of the total anhydrous gypsum to be added) is added to the pulverized product and mixed to produce an Irwin hydraulic composition. did. Table 5 shows the Blaine specific surface area of the obtained Irwin hydraulic composition.

3. Measurement of pot life and compressive strength (1) Preparation of mortar According to the formulation shown in Table 6, a mortar was prepared in which the addition ratio of the setting retarder was set to 3 levels. The materials shown in Table 6 were as follows.
・ Hydraulic composition: The above Irwin hydraulic composition ・ Sand: Standard sand for cement strength test (sold by the Japan Cement Association)
Water: Sakura City, Chiba Pref. Water-reducing agent: Naphthalenesulfonic acid-based water reducing agent (trade name Mighty 150 [registered trademark], manufactured by Kao Corporation)
-Setting retarder: Citric acid (reagent grade 1, manufactured by Kanto Chemical Co., Inc.)

(2) Measurement of pot life The pot life was evaluated with a zero-stroke flow of mortar. Specifically, using the flow table described in JIS R 5201 “Physical Test of Cement”, the flow value after the mortar prepared above is put in a plastic cylinder of φ51 × 26 mm until it is frayed and the cylinder is pulled out. (0 stroke) was measured. In addition, the mortar which shows the flow value of 100 mm or more by this measurement was determined as a mortar in a usable state. Table 7 shows the measurement results. In addition, the flow value of 100 mm or more is shown in italics.

  As shown in Table 7, the pot life of Examples 1 to 8 is almost the same as the pot life of Comparative Example 1 corresponding to the conventional Irwin hydraulic composition. In particular, the amount of setting retarder used in Example 3 and Example 5 is half that of Comparative Example 1, and it should be noted that it is possible to use Example 6 without using the set retarder. The working time is the same as the working time of Comparative Example 1 containing a setting retarder. As described above, the Irwin hydraulic composition of the present invention can sufficiently ensure a pot life that can be practically used even when the amount of the setting retarder is reduced or not added.

(3) Measurement of compressive strength The compressive strength was measured using the mortars of Examples 1 to 8, Comparative Example 1 and Comparative Example 2. Specifically, a 20 × 20 × 30 mm mold placed on a table vibrator described in JIS R 5201 “Cement physical test” is packed with one layer of mortar, and after 30 seconds of vibration, the surface is smoothed. Finished. Next, after sealing and curing in the mold until the age of 1 day, the mortar is demolded, and then the mortar is cured in water. When the age is 2 hours, 3 hours, 1 day, and 7 days, the mortar The compressive strength of was measured. The measurement results are shown in Table 8 and FIG.

  As shown in Table 8 and FIG. 1, at the age of 7 days, the compressive strength of Example 3 in which the amount of setting retarder used was half that of Comparative Example 1 and Example 6 in which no setting retarder was used, This is equivalent to the compression strength of Comparative Example 1. Therefore, the Irwin hydraulic composition of the present invention can secure a sufficient pot life without using a large amount of a setting retarder and is excellent in strength development.

Claims (6)

80 to 150 parts by mass of Portland cement clinker powder and 20 to 50 parts by mass of anhydrous gypsum powder with respect to 100 parts by mass of phosphorus-containing Irwin clinker powder containing 0.25 to 2.0 mass% of phosphorus in terms of P ₂ O ₅ An Irwin hydraulic composition comprising at least. The phosphorus-containing Irwin system clinker, Erwin _{(3CaO · 3Al 2 O 3 ·} CaSO 4) 40~80 % by weight, and belite (2CaO _· SiO 2) comprises at least 10 to 40% by weight, of claim 1 Erwin hydraulic composition. The Irwin hydraulic composition according to claim 1 or 2 , wherein the Portland cement clinker powder is an early Portland cement clinker powder or a normal Portland cement clinker powder. The Irwin hydraulic composition according to any one of claims 1 to 3 , wherein at least one set retarder selected from citric acid, heptonic acid, succinic acid, tartaric acid, and salts thereof is 100 parts by mass. Irwin-based hydraulic composition containing a setting retarder, containing 0.5 parts by mass or less based on the amount. 5 or less parts by mass of one or more setting accelerators selected from lithium carbonate, calcium nitrite, and calcium lactate with respect to 100 parts by mass of the Irwin hydraulic composition according to any one of claims 1 to 4. An Irwin hydraulic composition containing a setting accelerator. As the phosphorus raw material of the phosphorus-containing Irwin based clinker, sludge containing metal, using one or more selected from sewage sludge, and livestock waste (animal manure), according to any one of claims 1 to 5 The manufacturing method of an Irwin hydraulic composition which manufactures the Irwin hydraulic composition of this.