CN113636767A - Low-carbon cement and preparation method thereof - Google Patents
Low-carbon cement and preparation method thereof Download PDFInfo
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- CN113636767A CN113636767A CN202110750641.9A CN202110750641A CN113636767A CN 113636767 A CN113636767 A CN 113636767A CN 202110750641 A CN202110750641 A CN 202110750641A CN 113636767 A CN113636767 A CN 113636767A
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B7/00—Hydraulic cements
- C04B7/14—Cements containing slag
- C04B7/147—Metallurgical slag
- C04B7/153—Mixtures thereof with other inorganic cementitious materials or other activators
- C04B7/17—Mixtures thereof with other inorganic cementitious materials or other activators with calcium oxide containing activators
- C04B7/19—Portland cements
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B7/00—Hydraulic cements
- C04B7/14—Cements containing slag
- C04B7/147—Metallurgical slag
- C04B7/153—Mixtures thereof with other inorganic cementitious materials or other activators
- C04B7/1535—Mixtures thereof with other inorganic cementitious materials or other activators with alkali metal containing activators, e.g. sodium hydroxide or waterglass
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B7/00—Hydraulic cements
- C04B7/14—Cements containing slag
- C04B7/147—Metallurgical slag
- C04B7/153—Mixtures thereof with other inorganic cementitious materials or other activators
- C04B7/21—Mixtures thereof with other inorganic cementitious materials or other activators with calcium sulfate containing activators
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B7/00—Hydraulic cements
- C04B7/24—Cements from oil shales, residues or waste other than slag
- C04B7/243—Mixtures thereof with activators or composition-correcting additives, e.g. mixtures of fly ash and alkali activators
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B7/00—Hydraulic cements
- C04B7/36—Manufacture of hydraulic cements in general
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/10—Production of cement, e.g. improving or optimising the production methods; Cement grinding
Abstract
The invention relates to cement, and discloses low-carbon cement, which contains industrial waste residue, portland cement, an alkaline activator, a hydrophobic additive and a water reducing agent, or further contains desulfurized gypsum; based on 100 parts by mass of industrial waste residues, 25-45 parts by mass of Portland cement, 1-3 parts by mass of a hydrophobic additive, 20-40 parts by mass of an alkaline activator, 0.5-1.5 parts by mass of a water reducing agent and 6-20 parts by mass of desulfurized gypsum; wherein the industrial waste residue is a mixture of mineral powder and fly ash or mineral powder. The invention also discloses a preparation method of the low-carbon cement. The low-carbon cement has better dry-wet cycle stability.
Description
Technical Field
The invention relates to cement, in particular to low-carbon cement and a preparation method thereof.
Background
Currently, about 40 million tons of cement are produced worldwide each year, and the amount of fossil fuel burned in this process accounts for about 8% of the global carbon dioxide emission. With the accelerating urbanization process of 30 years in the future, the number is increased to 50 hundred million tons, and the urban environment is greatly influenced. On the other hand, the production of cement consumes a large amount of valuable resources such as clay and limestone. Researchers and pioneers are studying low carbon methods to improve this situation, including adjusting the balance of ingredients used in the production of cement, using carbon capture and storage technologies to eliminate emissions, and completely removing cement from concrete.
The incorporation of mineral admixtures into portland cement is a method for preparing composite cement, but the incorporation of mineral admixtures has problems of slow setting and hardening, low early strength, and a limitation in the amount of incorporation. On the other hand, researchers have developed a cement analog, CO, during the production process2And (3) waiting for a sustainable cementing material with extremely low gas, namely an alkali-activated cementing material. However, the alkali-activated cementing material still has some technical problems when being applied to building engineering, for example, the performance of the alkali-activated cementing material is greatly reduced in a dry-wet cycle environment, and the alkali-activated cementing material is not suitable for areas with more dry-wet alternation, underground engineering with dynamic dry-wet change, bridges with larger hydrological change, ramps and other constructions.
Disclosure of Invention
The invention aims to solve the technical problem of providing low-carbon cement and a preparation method thereof, wherein the low-carbon cement has better dry-wet cycle stability.
In order to achieve the above object, a first aspect of the present invention provides a low-carbon cement comprising industrial waste, portland cement, an alkali-activator, and a water-reducing agent, or further comprising desulfurized gypsum; based on 100 parts by mass of industrial waste residues, 25-45 parts by mass of Portland cement, 20-35 parts by mass of an alkaline activator, 1-3 parts by mass of a hydrophobic additive, 0.5-1.5 parts by mass of a water reducing agent and 6-20 parts by mass of desulfurized gypsum; wherein the industrial waste residue is a mixture of mineral powder and fly ash or mineral powder.
Preferably, based on 100 parts by mass of industrial waste residues, 25-45 parts by mass of portland cement, 26-35 parts by mass of an alkaline activator, 1-3 parts by mass of a hydrophobic additive and 0.5-1 part by mass of a water reducing agent are used.
Preferably, the industrial waste residue is a mixture of mineral powder and fly ash.
Preferably, the alkali activator is a liquid activator formed by mixing water glass and alkali, wherein the modulus of the liquid activator is 1-1.5, and the alkali is sodium hydroxide and/or potassium hydroxide.
Further preferably, the water glass is sodium silicate, the alkali is sodium hydroxide, the content of sodium silicate in the alkali activator is 25 to 35 mass%, and the content of alkali in the alkali activator is 3 to 5 mass% in terms of sodium oxide.
Preferably, the water-increasing additive is a silane water repellent.
Preferably, the water reducing agent is a carboxylic acid water reducing agent.
Preferably, the mass ratio of the portland cement to the alkali-activator is 1: 0.5-1.5.
In a second aspect, the invention provides a preparation method of low-carbon cement, which comprises the following steps:
uniformly mixing industrial waste residue, Portland cement, an alkaline activator and a water reducing agent, or uniformly mixing the industrial waste residue, the Portland cement, desulfurized gypsum, the alkaline activator, a hydrophobic additive and the water reducing agent to obtain the low-carbon cement;
the industrial waste residue is a mixture of mineral powder and fly ash or mineral powder, based on 100 parts by mass of the industrial waste residue, 25-45 parts by mass of portland cement, 20-40 parts by mass of an alkaline activator, 1-3 parts by mass of a hydrophobic additive, 0.5-1.5 parts by mass of a water reducing agent, or 6-20 parts by mass of desulfurized gypsum.
Preferably, the mass parts of the industrial waste residue are 100 parts by mass, the mass parts of the portland cement are 25-45 parts by mass, the mass parts of the alkali activator are 26-35 parts by mass, the mass parts of the hydrophobic additive are 1-3 parts by mass, and the mass parts of the water reducing agent are 0.5-1 part by mass.
Preferably, the industrial waste residue is a mixture of mineral powder and fly ash.
Preferably, the alkali activator is a liquid activator formed by mixing water glass and alkali, wherein the modulus of the liquid activator is 1-1.5, and the alkali is sodium hydroxide and/or potassium hydroxide.
Further preferably, the water glass is sodium silicate, the alkali is sodium hydroxide, the content of sodium silicate in the alkali activator is 25 to 35 mass%, and the content of alkali in the alkali activator is 3 to 5 mass% in terms of sodium oxide.
Preferably, the water-increasing additive is a silane water repellent.
Preferably, the water reducing agent is a carboxylic acid water reducing agent.
Preferably, the mass ratio of the portland cement to the alkali-activator is 1: 0.5-1.5.
Through the technical scheme, the invention has the beneficial effects that:
1. the low-carbon cement provided by the invention adopts the combination of the mineral powder and the fly ash or the mineral powder as the industrial waste residue, and can effectively improve the dry-wet cycle stability of the low-carbon cement through the interaction of the industrial waste residue, the portland cement, the alkaline activator and the hydrophobic additive, so that the low-carbon cement is more suitable for buildings and construction projects with more rainy days, and the shrinkage of the low-carbon cement in the cement coagulation process and the coagulation time of the low-carbon cement can be controlled while the strength and the durability of a low-carbon cement product are ensured.
2. The mineral powder and the fly ash are used as basic raw materials, so that the waste and pollution of land resources caused by long-term accumulation of slag and fly ash industrial solid wastes are solved, the using amount of portland cement is reduced, the energy consumption and environmental problems caused by cement production are reduced, and the requirements of energy conservation, emission reduction and green low-carbon sustainable development are met.
Detailed Description
The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.
In a first aspect, the invention provides a carbon cement, wherein the low-carbon cement contains industrial waste residue, portland cement, an alkaline activator, a hydrophobic additive and a water reducing agent, or further contains desulfurized gypsum; based on 100 parts by mass of industrial waste residues, 25-45 parts by mass of Portland cement, 20-40 parts by mass of an alkaline activator, 1-3 parts by mass of a hydrophobic additive, 0.5-1.5 parts by mass of a water reducing agent and 6-20 parts by mass of desulfurized gypsum; wherein the industrial waste residue is a mixture of mineral powder and fly ash or mineral powder.
Specifically, the alkali activator may be an alkali activator capable of achieving an alkali activation effect in the prior art, such as water glass, water glass added with sodium hydroxide and potassium hydroxide, and the like; the water reducing agent can be a water reducing agent which can be applied to cement in the prior art.
The mineral powder and the fly ash can be mixed in any proportion by a person skilled in the art according to actual conditions.
The inventor of the invention discovers in the research process that the combination of mineral powder and fly ash or mineral powder is used as industrial waste residue, and the low-carbon cement is matched with the industrial waste residue, Portland cement and an alkaline activator in a specific ratio, so that the dry-wet cycle stability of the cement can be effectively improved, the low-carbon cement is more suitable for buildings and construction projects with more rainy days, and the shrinkage in the cement coagulation process and the coagulation time of the low-carbon cement can be reduced to meet the construction requirements while the strength and the durability of a low-carbon cement product are ensured.
In order to further improve the dry-wet cycle stability of the low-carbon cement product, preferably, based on 100 parts by mass of the industrial waste residue, 25-45 parts by mass of the portland cement, 26-35 parts by mass of the alkaline activator, 1-3 parts by mass of the hydrophobic additive, and 0.5-1 part by mass of the water reducing agent are used.
In order to further improve the dry-wet cycle stability of the low-carbon cement product, preferably, based on 100 parts by mass of the industrial waste residue, 30-33 parts by mass of the portland cement, 26-30 parts by mass of the alkaline activator, 2-3 parts by mass of the hydrophobic additive and 0.5-1 part by mass of the water reducing agent are used.
In order to further improve the dry-wet cycle stability of the low-carbon cement product and reduce the setting time during the use of the cement, preferably, the mineral powder is S95 grade or above, and the fly ash is I grade ash or II grade ash. Specifically, the particle size of the mineral powder is 1-45 μm, and the particle size of the fly ash is 1-100 μm. In order to be able to further improve the strength and durability of the low carbon cement product while reducing the setting time during the use of cement, it is preferable that the slag have an average particle size of 15 to 35 μm and the fly ash have an average particle size of 30 to 45 μm.
In order to further improve the dry-wet cycle stability of the low-carbon cement product and reduce the setting time of the cement product during use, the industrial waste residue is preferably a mixture of mineral powder and fly ash.
Specifically, the mineral powder and the fly ash can be mixed in any ratio. Preferably, in order to further improve the strength of the low-carbon cement product, the mass percentage of the mineral powder in the mixture of the mineral powder and the fly ash is 50-90%.
The alkali activator is preferably a mixture of alkali and alkali metal silicate; the base may be an inorganic base conventionally used in the art, such as sodium hydroxide and/or potassium hydroxide, and the alkali metal silicate is preferably sodium silicate. In order to further improve the strength and durability of the low-carbon cement product, preferably, the alkali activator is a liquid activator formed by mixing water glass and alkali, wherein the modulus of the liquid activator is 1-1.5, and the alkali is sodium hydroxide and/or potassium hydroxide.
In order to further improve the strength and durability of the low-carbon cement product, preferably, the water glass is sodium silicate, the alkali is sodium hydroxide, the content of the sodium silicate in the alkali-activator is 25 to 35 mass%, and the content of the alkali in the alkali-activator is 3 to 5 mass% in terms of sodium oxide.
The hydrophobic additive can be any one of water repellents in the prior art. In order to further improve the dry-wet cycle stability of the low-carbon cement product, the water-increasing additive is preferably a silane water repellent.
In order to further improve the dry-wet cycle stability of the low-carbon cement product, the water reducing agent is preferably a carboxylic acid water reducing agent.
In order to further reduce the shrinkage of the low-carbon cement product, the desulfurized gypsum is preferably calcination-free desulfurized gypsum, namely, untreated desulfurized gypsum.
In order to further improve the dry-wet cycle stability of the low-carbon cement product, the mass ratio of the portland cement to the alkali-activator is preferably 1: 0.5-1.5.
In order to further improve the dry-wet cycle stability of the low-carbon cement product, the mass ratio of the portland cement to the alkali-activator is preferably 1:0.5-1.
In a second aspect, the invention provides a preparation method of low-carbon cement, which comprises the following steps:
uniformly mixing industrial waste residue, Portland cement, an alkaline activator and a water reducing agent, or uniformly mixing the industrial waste residue, the Portland cement, desulfurized gypsum, the alkaline activator, a hydrophobic additive and the water reducing agent to obtain the low-carbon cement;
the industrial waste residue is a mixture of mineral powder and fly ash or mineral powder, based on 100 parts by mass of the industrial waste residue, 25-45 parts by mass of portland cement, 20-40 parts by mass of an alkaline activator, 1-3 parts by mass of a hydrophobic additive, 0.5-1.5 parts by mass of a water reducing agent, or 6-20 parts by mass of desulfurized gypsum.
According to the invention, the raw material components can be mixed in one step or in multiple steps, preferably, the solid is mixed and then the liquid is added for mixing, so that the components in the low-carbon cement can be mixed more uniformly. Specifically, the industrial waste residue and the portland cement are uniformly mixed, and then the alkaline activator and the water reducing agent are added into the mixture and uniformly stirred; or, uniformly mixing the industrial waste residue, the Portland cement and the desulfurized gypsum, adding the alkaline activator, the hydrophobic additive and the water reducing agent into the mixture, and uniformly stirring to obtain the low-carbon cement.
In order to further improve the dry-wet cycle stability of the low-carbon cement product, preferably, the mass portion of the industrial waste residue is 100 parts by mass, the mass portion of the portland cement is 25-45 parts by mass, the mass portion of the alkali activator is 26-35 parts by mass, the mass portion of the hydrophobic additive is 1-3 parts by mass, and the mass portion of the water reducing agent is 0.5-1 part by mass.
In order to further improve the dry-wet cycle stability of the low-carbon cement product, preferably, based on 100 parts by mass of the industrial waste residue, 30-33 parts by mass of the portland cement, 26-30 parts by mass of the alkaline activator, 2-3 parts by mass of the hydrophobic additive and 0.5-1 part by mass of the water reducing agent are used.
In order to further improve the dry-wet cycle stability of the low-carbon cement product and reduce the setting time of the cement product in use, preferably, the mineral powder is S95 grade or above, and the fly ash is I grade ash. Specifically, the particle size of the mineral powder is 1-45 μm, and the particle size of the fly ash is 1-100 μm. In order to be able to further improve the strength and durability of the low carbon cement product while reducing the setting time during the use of cement, it is preferable that the slag have an average particle size of 15 to 35 μm and the fly ash have an average particle size of 30 to 45 μm.
In order to further improve the dry-wet cycle stability of the low-carbon cement product and reduce the setting time of the cement product in use, the industrial waste residue is preferably mineral powder.
In order to further improve the strength and durability of the low-carbon cement product, preferably, the alkali activator is a liquid activator formed by mixing water glass and alkali, wherein the modulus of the liquid activator is 1-1.5, and the alkali is sodium hydroxide and/or potassium hydroxide.
Although the ratio of the alkali and the alkali metal silicate may be selected within a wide range, in order to further improve the strength and durability of the low carbon cement product, it is preferable that the water glass is sodium silicate, the alkali is sodium hydroxide, the content of the sodium silicate in the alkali activator is 25 to 35 mass%, and the content of the alkali in the alkali activator is 3 to 5 mass% in terms of sodium oxide.
The hydrophobic additive can be any one of water repellents in the prior art. In order to further improve the dry-wet cycle stability of the low-carbon cement product, the hydrophobic additive is preferably a silane water repellent.
In order to further improve the dry-wet cycle stability of the low-carbon cement product, the water reducing agent is preferably a carboxylic acid water reducing agent.
In order to further improve the dry-wet cycle stability of the low-carbon cement product, the mass ratio of the portland cement to the alkali-activator is preferably 1: 0.5-1.5.
In order to further improve the dry-wet cycle stability of the low-carbon cement product, the mass ratio of the portland cement to the alkali-activator is preferably 1:0.5-1.
The present invention will be described in detail below by way of examples. In the following examples, the dry-wet cycle stability was tested according to the test method for autoclaved aerated concrete Performance (GB// T11969-2008), and the test piece size was 100mm × 100mm × 100 mm; the compressive strength is tested according to the cement mortar strength test method (GB/T17671-1999); the setting time is tested according to the method for testing water consumption, setting time and stability of standard consistency of cement (GBT 1346-2011); shrinkage was measured according to Cement mortar Dry shrinkage test method (JC/T603-2004).
The water glass was purchased from Shanghai national reagent Co., Ltd, and the content of sodium silicate was 47% by mass. Mixing the water glass, water and sodium hydroxide to prepare the required alkali activator; wherein the alkali activator-1 contains 30 mass% of sodium silicate, 6.6 mass% of sodium hydroxide, and a modulus of 1; the alkali activator-2 contains 25 mass% of sodium silicate, 5.5 mass% of sodium hydroxide, and a modulus of 1.2; the alkali activator 3-contains 30 mass% of sodium silicate, 0 mass% of sodium hydroxide, and a modulus of 1.5.
The specific surface area of the ore powder is 448m2Per kg, the grain diameter is 15-35 mu m; the specific surface area of the fly ash is 420m2Per kg, the grain diameter is 30-45 μm; portland cement is available from southern Cement, Inc.
The hydrophobic additive is purchased from silane water repellents of Shandong Dinghong New Material Co., Ltd, and the solid content is 28-35%; the polycarboxylic acid high-efficiency water reducing agent (the following water reducing agent-1 belongs to carboxylic acid water reducing agents) is purchased from Subot New materials GmbH, and the product number is PCA-HW; the polycarboxylate superplasticizer (hereinafter called as the water reducer-2, belonging to carboxylic acid water reducers) is purchased from Subot New materials GmbH, and the product number is PCA-I; the high-performance water reducing agent (the water reducing agent-3 belongs to naphthalene water reducing agents) is purchased from Kanaier chemical Limited company and has the product number of NS-800.
Example 1
And uniformly mixing 100 parts by mass of mineral powder and 45 parts by mass of portland cement, adding 35 parts by mass of alkaline activator-2, 1 part by mass of silane water repellent and 1 part by mass of water reducer-2, and uniformly stirring to obtain the low-carbon cement.
Example 2
And uniformly mixing 100 parts by mass of mineral powder and 25 parts by mass of portland cement, adding 35 parts by mass of alkaline activator-1, 1 part by mass of silane water repellent and 0.5 part by mass of water reducer-2, and uniformly stirring to obtain the low-carbon cement.
Example 3
And uniformly mixing 100 parts by mass of mineral powder and 30 parts by mass of portland cement, adding 30 parts by mass of alkaline activator-2, 2 parts by mass of silane water repellent and 1 part by mass of water reducer-2, and uniformly stirring to obtain the low-carbon cement.
Example 4
And uniformly mixing 100 parts by mass of mineral powder and 33 parts by mass of portland cement, adding 26 parts by mass of alkaline activator-1, 3 parts by mass of silane water repellent and 0.7 part by mass of water reducer-1, and uniformly stirring to obtain the low-carbon cement.
Example 5
And uniformly mixing 100 parts by mass of mineral powder and 40 parts by mass of portland cement, adding 22 parts by mass of alkaline activator-1, 1 part by mass of silane water repellent and 0.5 part by mass of water reducer-1, and uniformly stirring to obtain the low-carbon cement.
Example 6
And uniformly mixing 100 parts by mass of mineral powder and 25 parts by mass of portland cement, adding 20 parts by mass of alkaline activator-3, 2 parts by mass of silane water repellent and 0.5 part by mass of water reducer-1, and uniformly stirring to obtain the low-carbon cement.
Example 7
And uniformly mixing 100 parts by mass of mineral powder and 45 parts by mass of portland cement, adding 40 parts by mass of alkaline activator-3, 2 parts by mass of silane water repellent and 1.5 parts by mass of water reducer-1, and uniformly stirring to obtain the low-carbon cement.
Example 8
67 parts by mass of mineral powder, 33 parts by mass of fly ash and 33 parts by mass of portland cement are uniformly mixed, 26 parts by mass of alkaline activator-1, 3 parts by mass of silane water repellent and 0.7 part by mass of water reducer-1 are added, and the mixture is uniformly stirred to obtain the low-carbon cement.
Example 9
Uniformly mixing 100 parts by mass of mineral powder, 33 parts by mass of Portland cement and 6 parts by mass of desulfurized gypsum, adding 26 parts by mass of alkaline activator-1, 3 parts by mass of silane water repellent and 0.7 part by mass of water reducing agent-1, and uniformly stirring to obtain the low-carbon cement.
Example 10
Uniformly mixing 100 parts by mass of mineral powder, 33 parts by mass of Portland cement and 20 parts by mass of desulfurized gypsum, adding 26 parts by mass of alkaline activator-1, 3 parts by mass of silane water repellent and 0.7 part by mass of water reducer-1, and uniformly stirring to obtain the low-carbon cement.
Example 11
And uniformly mixing 100 parts by mass of mineral powder and 45 parts by mass of portland cement, adding 20 parts by mass of alkaline activator-2, 2 parts by mass of silane water repellent and 1 part by mass of water reducer-1, and uniformly stirring to obtain the low-carbon cement.
Example 12
67 parts by mass of mineral powder, 33 parts by mass of fly ash and 33 parts by mass of portland cement are uniformly mixed, 26 parts by mass of alkaline activator-3, 3 parts by mass of silane water repellent and 0.7 part by mass of water reducer-3 are added, and the mixture is uniformly stirred to obtain the low-carbon cement.
Comparative example 1
And (2) mixing and uniformly stirring 100 parts by mass of mineral powder, 35 parts by mass of alkaline activator-3, 1 part by mass of silane water repellent and 0.5 part by mass of water reducer-1 to obtain the low-carbon cement.
Comparative example 2
And (2) uniformly mixing and stirring 100 parts by mass of ceramic polishing slag, 25 parts by mass of Portland cement, 35 parts by mass of alkaline activator-3, 1 part by mass of silane water repellent and 0.5 part by mass of water reducing agent-1 to obtain the low-carbon cement.
Comparative example 3
And uniformly mixing 100 parts by mass of mineral powder and 25 parts by mass of portland cement, adding 0.5 part by mass of water reducing agent-1, and uniformly stirring 1 part by mass of silane water repellent to obtain the low-carbon cement.
Test example
Mixing the above examples 1-12 and comparative examples 1-3 with water according to the mass ratio of the low-carbon cement to the water of 13: 7, mixing, uniformly stirring, injecting into a mold, curing, demolding, and curing for 28 days by steam at normal temperature, wherein the initial setting time and the final setting time are recorded in the process. According to the specification, the test can be finished after 15 times of dry-wet circulation, and the dry-wet circulation frequency is designed to be 50 times in order to better verify the dry-wet circulation stability of the low-carbon cement. During the wet cycle test, it was noted that the top surface of the test piece was at least 20mm from the water surface, and the results are shown in Table 1. The low carbon cement was measured for 1 day strength, 7 day strength, 28 strength, 80 ℃ steam cure (1 day) strength, and 28 day shrinkage, and the data are shown in table 2:
table 1 results of dry-wet cycle stability test in examples and comparative examples
| Number of wet and dry cycles | Loss rate of compressive strength% | Mass loss rate% | |
| Example 1 | 50 | 2.5 | 1.9 |
| Example 2 | 50 | 2.3 | 1.8 |
| Example 3 | 50 | 1.6 | 1.3 |
| Example 4 | 50 | 1.1 | 1 |
| Example 5 | 50 | 3.6 | 2.9 |
| Example 6 | 50 | 2.6 | 2.2 |
| Example 7 | 50 | 2.8 | 2.5 |
| Example 8 | 50 | 2.7 | 2.4 |
| Example 9 | 50 | 1.7 | 1.3 |
| Example 10 | 50 | 1.8 | 1.5 |
| Example 11 | 50 | 3.9 | 3.3 |
| Example 12 | 50 | 3.5 | 2.9 |
| Comparative example 1 | 50 | 8.3 | 7.2 |
| Comparative example 2 | 50 | 6.9 | 5.9 |
| Comparative example 3 | 50 | 6.6 | 6.2 |
TABLE 2 comparative tables of setting time, strength and shrinkage in the examples and comparative examples
By comparing the data of the above examples and comparative examples, it can be seen that the dry-wet stability of low-carbon cement can be effectively improved by mixing mineral powder and fly ash or compounding single mineral powder as industrial waste with portland cement and then adding a small amount of alkaline activator and hydrophobic additive, and the shrinkage of alkali-activated cement can be reduced while the strength and durability of low-carbon cement products are ensured. The addition of the desulfurized gypsum can effectively reduce the volume shrinkage of the cement product, and has a regulating and controlling effect on the setting time under the combined action of the desulfurized gypsum and the exciting agent. The addition of the Portland cement can effectively reduce the volume shrinkage of cement products.
The preferred embodiments of the present invention have been described above in detail, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the scope of the invention.
Claims (10)
1. The low-carbon cement is characterized by comprising industrial waste residue, portland cement, an alkaline activator, a hydrophobic additive and a water reducing agent, or further comprising desulfurized gypsum; based on 100 parts by mass of industrial waste residues, 25-45 parts by mass of Portland cement, 20-40 parts by mass of an alkaline activator, 1-3 parts by mass of a hydrophobic additive, 0.5-1.5 parts by mass of a water reducing agent and 6-20 parts by mass of desulfurized gypsum;
wherein the industrial waste residue is a mixture of mineral powder and fly ash or mineral powder.
2. The low-carbon cement according to claim 1, wherein the portland cement is 25 to 45 parts by mass, the alkali activator is 26 to 35 parts by mass, the hydrophobic additive is 1 to 3 parts by mass, and the water reducing agent is 0.5 to 1 part by mass, based on 100 parts by mass of the industrial waste residue.
3. The low carbon cement of claim 1 or 2, wherein the industrial waste residue is a mixture of mineral powder and fly ash.
4. The low-carbon cement according to claim 1 or 2, wherein the alkali activator is a liquid activator formed by mixing water glass and alkali, and the modulus of the liquid activator is 1-1.5, and the alkali is sodium hydroxide and/or potassium hydroxide;
preferably, the water glass is sodium silicate, the alkali is sodium hydroxide, the content of the sodium silicate in the alkali activator is 25-35% by mass, and the content of the alkali in the alkali activator is 3-5% by mass in terms of sodium oxide;
the hydrophobic additive is a silane water repellent;
the water reducing agent is a carboxylic acid water reducing agent.
5. The low carbon cement of claim 1 or 2, wherein the mass ratio of the portland cement to the alkali-activator is 1: 0.5-1.5.
6. The preparation method of the low-carbon cement is characterized by comprising the following steps of:
uniformly mixing industrial waste residue, Portland cement, an alkaline activator and a water reducing agent, or uniformly mixing the industrial waste residue, the Portland cement, desulfurized gypsum, the alkaline activator, a hydrophobic additive and the water reducing agent to obtain the low-carbon cement;
the industrial waste residue is a mixture of mineral powder and fly ash or mineral powder, based on 100 parts by mass of the industrial waste residue, 25-45 parts by mass of portland cement, 20-40 parts by mass of an alkaline activator, 1-3 parts by mass of a hydrophobic additive, 0.5-1.5 parts by mass of a water reducing agent, or 6-20 parts by mass of desulfurized gypsum.
7. The method for preparing low-carbon cement according to claim 6, wherein the portland cement is 25 to 45 parts by mass, the alkali activator is 26 to 35 parts by mass, the hydrophobic additive is 1 to 3 parts by mass, and the water reducing agent is 0.5 to 1 part by mass, based on 100 parts by mass of the industrial waste residue.
8. The method for preparing low-carbon cement according to claim 6 or 7, wherein the industrial waste residue is a mixture of mineral powder and fly ash.
9. The method for preparing the low-carbon cement according to claim 6 or 7, wherein the alkali activator is a liquid activator formed by mixing water glass and alkali, and the modulus of the liquid activator is 1-1.5, and the alkali is sodium hydroxide and/or potassium hydroxide;
preferably, the water glass is sodium silicate, the alkali is sodium hydroxide, the content of the sodium silicate in the alkali activator is 25-35% by mass, and the content of the alkali in the alkali activator is 3-5% by mass in terms of sodium oxide;
the water increasing additive is a silane water repellent;
the water reducing agent is a carboxylic acid water reducing agent.
10. The method for producing low carbon cement according to claim 6 or 7, wherein the mass ratio of the portland cement to the alkali-activator is 1: 0.5-1.5.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114477801A (en) * | 2022-02-14 | 2022-05-13 | 中建材中研益科技有限公司 | Low-carbon cement and preparation method thereof |
| CN115626811A (en) * | 2022-09-05 | 2023-01-20 | 上海建工集团股份有限公司 | Precast concrete of cement-alkali activated aluminosilicate cementing system and preparation method thereof |
| CN116553858A (en) * | 2023-07-04 | 2023-08-08 | 湖南凝英新材料科技有限公司 | Low-carbon concrete additive and preparation method and application thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108623196A (en) * | 2018-06-15 | 2018-10-09 | 东南大学 | A kind of lime excitation large dosage industrial residue low-carbon cement and preparation method thereof |
| CN112341107A (en) * | 2020-11-23 | 2021-02-09 | 广西云燕特种水泥建材有限公司 | Method for energy-saving production of composite high-strength cement by using various industrial wastes |
-
2021
- 2021-07-02 CN CN202110750641.9A patent/CN113636767A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108623196A (en) * | 2018-06-15 | 2018-10-09 | 东南大学 | A kind of lime excitation large dosage industrial residue low-carbon cement and preparation method thereof |
| CN112341107A (en) * | 2020-11-23 | 2021-02-09 | 广西云燕特种水泥建材有限公司 | Method for energy-saving production of composite high-strength cement by using various industrial wastes |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114477801A (en) * | 2022-02-14 | 2022-05-13 | 中建材中研益科技有限公司 | Low-carbon cement and preparation method thereof |
| CN115626811A (en) * | 2022-09-05 | 2023-01-20 | 上海建工集团股份有限公司 | Precast concrete of cement-alkali activated aluminosilicate cementing system and preparation method thereof |
| CN116553858A (en) * | 2023-07-04 | 2023-08-08 | 湖南凝英新材料科技有限公司 | Low-carbon concrete additive and preparation method and application thereof |
| CN116553858B (en) * | 2023-07-04 | 2023-09-05 | 湖南凝英新材料科技有限公司 | Low-carbon concrete additive and preparation method and application thereof |
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