Solid waste-based marine engineering cementitious material and preparation method thereof, and offshore wind power grouting material

Abstract

The invention discloses a solid waste-based marine engineering cementitious material and a preparation method thereof as well as an offshore wind power grouting material, which relates to the technical field of concrete materials, including: modified tailings: 200-400 parts, ceramic polishing mud: 50-100 parts, fluorgypsum: 50-100 parts, red mud: 100-150 parts, and an activator: 10-30 parts. The modified tailings are obtained by grinding tailings powder after acidification treatment and mixing with carbide slag and activating at a high temperature of more than 600°C, and the activator includes a stabilizing component and an activating component. The present invention uses gold tailings powder with a huge stockpile as the main material, and synergistically uses solid wastes such as ceramic polishing mud, fluorgypsum, and red mud to prepare a solid waste-based cementitious material, and further prepares an offshore wind power grouting material with excellent workability, mechanical properties, and durability with tunnel slag machine-made sand and a variety of admixtures.

Description

Technical Field

[0001] The present invention relates to the technical field of building materials, and in particular to a solid waste-based marine engineering cementitious material and a preparation method thereof, as well as an offshore wind power grouting material. Background Art

[0002] Offshore wind power is a new type of clean energy industry with high power generation efficiency and less land requirements. In offshore wind power projects, wind turbines are usually fixed to the seabed by pouring concrete foundations, and grouting materials are used to fill and fix the gap between the foundation and the seabed to enhance the fixing effect, improve stability and extend service life.

[0003] The seawater environment has high requirements for the performance of grouting materials, and the effects of seawater erosion, salt corrosion, tides and other factors on the performance of grouting materials need to be considered. Wind power grouting materials prepared with traditional cementitious materials have high carbon emissions and poor resistance to sulfate and chloride corrosion. It is urgent to develop a new type of cementitious material with high ecological, workability, mechanical properties and durability for the preparation of offshore wind power grouting materials.

[0004] With the acceleration of industrialization, the treatment of solid waste has become an environmental problem that needs to be solved urgently. The landfill treatment of a large amount of solid waste not only wastes resources, but also causes land pollution and ecological damage. Therefore, it is necessary to effectively reduce the emission of solid waste through resource utilization; secondly, traditional building materials such as cement and mortar consume a lot of resources and high energy consumption. Research on solid waste-based cementitious materials can effectively reduce the use of traditional resources and reduce the construction industry's dependence on resources. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a solid waste-based marine engineering cementitious material with high solid waste utilization rate and high performance, a preparation method thereof, and an offshore wind power grouting material.

[0006] In order to solve the above technical problems, the solid waste-based marine engineering cementitious material of the present invention comprises, by weight, 200-400 parts of modified tailings, 50-100 parts of ceramic polishing mud, 50-100 parts of fluorgypsum, 100-150 parts of red mud, and 10-30 parts of activator. The modified tailings are obtained by mixing tailings powder with carbide slag after acidification and grinding and activating at a high temperature of more than 600°C. The cumulative mass percentage of SiO2, CaO and Al2O3 in the tailings powder is greater than 70%. The specific surface area of ​​the modified tailings is 700-900m 2 / kg, the specific surface area of ​​ceramic polishing mud is 900-1100 m 2 / kg, the specific surface area of ​​fluorgypsum is 210-250m 2 / kg, the specific surface area of ​​red mud is 1100-1200m 2 / kg, the mass content of SiO2 in ceramic polishing mud is above 90%, and the activator includes a stabilizing component and an exciting component.

[0007] Preferably, the tailings powder is made of gold tailings fine powder, the specific surface area of ​​the gold tailings fine powder is: 300-350㎡ / kg, and the modification process is: first, the gold tailings fine powder is acidified in 10mol / L composite acid for 10min, the molar ratio of hydrochloric acid to citric acid in the composite acid is 1:1, and the ratio of the gold tailings fine powder to the composite acid is 10kg:1L; then, drying treatment is performed, the dried gold tailings fine powder is mixed with carbide slag in a mass ratio of 10:1, and then ground with a ball mill until the specific surface area reaches 800m 2 / kg or more, and then the fine powder obtained by grinding is activated at a temperature of 600-700°C for 30 minutes to obtain highly active modified gold tailings powder.

[0008] Preferably, the stimulator comprises a stabilizing component and an stimulating component in a mass ratio of (1-3): (30-90); the stabilizing component comprises one or more of dibutyltin dilaurate, zinc stearate, antimony carboxylate, and phosphite; and the stimulating component comprises one or more of potassium silicate, lithium silicate, nano silicon powder, nano calcium oxide, and nano aluminum oxide.

[0009] Preferably, the specific surface area of ​​the modified tailings is 800-900m 2 / kg, the specific surface area of ​​ceramic polishing mud is 1000-1100m 2 / kg, the specific surface area of ​​fluorgypsum is 230-250m 2 / kg, the specific surface area of ​​red mud is 1150-1200m 2 / kg, the mass content of NaO in the red mud does not exceed 9%; the mass ratio of the stabilizing component to the exciting component of the stimulator is 2:60; the stabilizing component includes dibutyltin dilaurate, zinc stearate, antimony carboxylate, and phosphite in a mass ratio of (1-3): (1-3): (0.5-1.5): (1-3); the exciting component includes potassium silicate, lithium silicate, nano silicon powder, nano calcium oxide, and nano aluminum oxide in a mass ratio of (1-2): (1-2): (2-3): (2-3): (0.5-1).

[0010] Preferably, the cementitious material comprises, by weight, 400 parts of modified tailings, 100 parts of ceramic polishing mud, 100 parts of fluorgypsum, 150 parts of red mud and 15 parts of stimulator; in the stimulator, the mass ratio of the stabilizing component to the stimulating component is 2.1:66, and the stabilizing component includes dibutyltin dilaurate, zinc stearate, antimony carboxylate and phosphite in a mass ratio of 1:1:0.5:1; the stimulating component includes potassium silicate, lithium silicate, nano-silicon powder, nano-calcium oxide and nano-aluminum oxide in a mass ratio of 2:2:3:3:1.

[0011] The method for preparing the solid waste-based marine engineering cementitious material of the present invention comprises the following steps:

[0012] S1, the modified tailings powder, ceramic polishing mud, fluorgypsum, red mud and the exciting component are mixed evenly by a mixer to obtain a basic cementitious material A;

[0013] S2, homogenizing material A through a high-pressure homogenizer, wherein the pressure of the high-pressure homogenizer is between 100 and 500 atmospheres, to obtain a reinforced gelling material B;

[0014] S3. Evenly mix the reinforced cementitious material B and the stabilizer to obtain a finished solid waste-based marine engineering cementitious material.

[0015] Preferably, the pressure of the high pressure homogenizer is between 400-500 atmospheres.

[0016] The offshore wind power grouting material of the present invention comprises a cementitious material, an aggregate, an admixture and water; the cementitious material adopts any one of the solid waste-based marine engineering cementitious materials described above; in the grouting material, the mass ratio of the cementitious material, the aggregate and the admixture is (4-6): (3-6): (0.02-0.25), and the mass of the water is 0.17-0.22 times the mass of the cementitious material.

[0017] Preferably, the aggregate is machine-made sand prepared from tunnel slag, with a fineness modulus of 3.0-3.3; the admixture includes the following components in parts by weight: polycarboxylic acid high-performance water reducer: 2-3 parts, silicone defoamer: 0.1-0.3 parts, and infiltration crystallization material: 1-3 parts.

[0018] The activity index of unmodified gold tailings fine powder is very low, and the 28d strength activity index measured by the specific strength test is only 60%-70%. Through the four-component modification and activation process of acid modification, carbide slag modification, mechanical activation and high-temperature activation, the activity index of gold tailings powder can reach 95%-105%. Acid activation can remove impurities in gold tailings, optimize the pore structure and pore size, increase the reaction sites of carbide slag modification, and reduce the activation energy of mechanical activation and high-temperature activation; carbide slag contains a large amount of Ca(OH)2, which can optimize the pH value of the reaction system and provide a large amount of Ca source for the hydration reaction; mechanical grinding and high-temperature activation can produce a large number of lattice defects, which can break the Si-O and Al-O bonds on the surface of the tailings and recombine them into a low-crystallinity crystal structure, increase the glass content, and improve the activity.

[0019] Ceramic polishing mud is the waste generated during the grinding and polishing process of ceramic tiles. The particle morphology is close to spherical, which can play a ball lubrication effect. At the same time, the silicon content is relatively high, which can provide a large amount of Si source for the hydration reaction.

[0020] Fluorogypsum contains some residual hydrofluoric acid, which can neutralize the excess alkali in red mud, adjust the pH value, and also adjust the SO4 in the reaction system. 2- concentration, promoting the formation of ettringite and enhancing volume stability.

[0021] The red mud is preferably sintered red mud, which has relatively high activity and rich aluminum content, and can ensure the concentration of Al ions in the hydration reaction.

[0022] The synergistic effect of multiple stabilizers in the activator can prevent the solid waste-based marine grouting material from separating and bleeding, and enhance the bonding stability of the entire system. The activating components can fill the nanopores, enhance the density of the system, and prevent the invasion of harmful ions.

[0023] In the preparation project of solid waste-based marine engineering cementitious materials, high-pressure homogenization treatment is carried out. Through the effects of impact force, shear force and cavitation, the cementitious material particles are dispersed into a uniform state, which is more conducive to hydration.

[0024] The beneficial effects of the present invention are as follows: the present invention utilizes a huge amount of gold tailings powder as the main material, and synergistically utilizes solid wastes such as ceramic polishing mud, fluorgypsum, and red mud to prepare solid waste-based cementitious materials, and further prepares offshore wind power grouting materials with excellent workability, mechanical properties, and durability with tunnel slag machine-made sand and a variety of admixtures. In offshore wind power grouting materials, solid-based materials account for nearly 100%, which increases the added value and utilization rate of solid waste, has high ecological value, does not use cement clinker, does not consume non-renewable resources such as limestone and clay, and has high ecological value. At the same time, when nanomaterials and crystal core materials are added to the product, the product has a high density, can resist erosion from various extreme environments, has good durability, and increases the service life. DETAILED DESCRIPTION

[0025] The instruments, reagents, materials, etc. involved in the following embodiments, unless otherwise specified, are all conventional instruments, reagents, materials, etc. in the prior art and can be obtained through regular commercial channels. The experimental methods, detection methods, etc. involved in the following embodiments, unless otherwise specified, are all conventional experimental methods, detection methods, etc. in the prior art.

[0026] The solid waste-based marine cementitious materials of each embodiment of the present invention include modified tailings, ceramic polishing mud, fluorgypsum, red mud and an activator. The modified tailings are modified by gold tailings fine powder, and the specific surface area of ​​the gold tailings fine powder is: 300-350㎡ / kg. The modification process is: first, the gold tailings fine powder is acidified in 10mol / L composite acid for 10min, the molar ratio of hydrochloric acid to citric acid in the composite acid is 1:1, and the ratio of gold tailings fine powder to composite acid is 10kg:1L; then, drying treatment is performed, and the dried gold tailings fine powder is mixed with carbide slag in a mass ratio of 10:1, and then ground with a ball mill until the specific surface area reaches 800-900m2 / kg, and then the fine powder obtained by grinding is activated at 600-700℃ for 30min to obtain high-activity modified gold tailings powder.

[0027] The cumulative mass percentage of SiO2, CaO and Al2O3 in the fine gold tailings powder is greater than 70%, and the mass proportions of SiO2, CaO and Al2O3 are 38%, 21% and 13% respectively.

[0028] The specific surface area of ​​ceramic polishing mud is 1000-1100 m 2 / kg, the mass content of SiO2 is 92%.

[0029] The specific surface area of ​​fluorgypsum is 230-250m 2 / kg.

[0030] The specific surface area of ​​red mud is 1150-1200m 2 / kg, the mass content of NaO in red mud is 8%.

[0031] Gold tailings fine powder, carbide slag, ceramic polishing mud, fluorgypsum, and red mud were all purchased from Yantai Huamiao New Materials Technology Co., Ltd.

[0032] The stimulator used in the present invention includes a stabilizing component and an stimulating component. The specific components and the content of each component in the stimulator are shown in Table 1.

[0033] For Examples 1-5 of the solid waste-based marine engineering cementitious materials of the present invention, the specific components and the content of each component in the cementitious materials are shown in Table 2.

[0034] The offshore wind power grouting material of the present invention comprises a cementitious material, an aggregate, an admixture and water, wherein the aggregate is machine-made sand prepared from tunnel slag, and the fineness modulus is 3.0-3.3. The mass of water is 0.2 times the mass of the cementitious material. The specific components of the offshore wind power grouting material and the content of each component in the grouting material are shown in Table 3.

[0035] The admixtures are of the following two types:

[0036] The admixture 1 is, in parts by mass, the following: polycarboxylic acid high performance water reducing agent: 2 parts, silicone defoaming agent: 0.3 parts, and penetrating crystallization material: 3 parts.

[0037] Admixture 2 is, in the admixture, calculated by mass: polycarboxylic acid high-performance water-reducing agent: 3 parts, silicone defoaming agent: 0.1 parts, and penetrating crystallization material: 1 part.

[0038] The models of the admixtures in the embodiments of the present invention are: polycarboxylic acid high-performance water-reducing agent: PC860, silicone defoaming agent: XP01, penetrating crystallization material: H8-5860, carboxylic acid ester antimony: ST-Ⅱ, and the admixtures are all produced by Shandong Huadi Building Technology Co., Ltd.

[0039] Table 1 List of exciter components (unit: parts by weight)

[0040]

[0041] Table 2 List of components of solid waste-based marine cementitious materials (in parts by weight)

[0042]

[0043] Table 3 List of components of offshore wind power grouting materials (in parts by weight)

[0044]

[0045] The solid waste-based marine cementitious materials prepared in various embodiments of the present invention include the following steps:

[0046] S1, the modified tailings powder, ceramic polishing mud, fluorgypsum, red mud and the exciting component are mixed evenly by a mixer to obtain a basic cementitious material A;

[0047] S2, homogenizing material A through a high-pressure homogenizer, the pressure of the high-pressure homogenizer is between 400-500 atmospheres, and obtaining a reinforced gelling material B; slowly conveying material A to the high-pressure homogenizer, material A passes through the valve port of the high-pressure homogenizer under high pressure, and is further refined under the action of impact force and shear force; after passing through the valve port, the pressure is rapidly lost, so that material A is further broken;

[0048] S4. Evenly mix the reinforced cementitious material B and the stabilizer to obtain a finished solid waste-based marine engineering cementitious material.

[0049] Furthermore, solid waste-based marine engineering cementitious materials can be used to prepare offshore wind power grouting materials, and the cementitious materials, aggregates, admixtures and water can be evenly mixed.

[0050] The grouting materials 1-7 were tested for performance, and the test results are as follows:

[0051]

[0052] The compressive strength test method is carried out in accordance with the compressive strength test method specified in GB / T 50448-2015 "Technical Specifications for Application of Cement-based Grouting Materials". The fluidity adopts the truncated cone fluidity test method specified in GB / T 50448-2015, and the 30-minute truncated cone fluidity is tested. The frost resistance test method is carried out in accordance with 4.1 slow freezing method in GB / T50082-2024 "Standard for Test Methods for Long-term Performance and Durability of Concrete", and the sulfate erosion resistance test is carried out in accordance with 14 sulfate erosion resistance test in GB / T50082-2024. The tensile strength test method is carried out in accordance with 11 axial tensile test in GB / T 50081-2019 "Standard for Test Methods for Physical and Mechanical Properties of Concrete", and the axial tensile strength is tested.

[0053] By comparing grouting materials 1-5 with comparative grouting materials 6-7, it can be found that the mechanical properties, fluidity and durability of wind power grouting materials prepared from solid waste-based marine engineering cementitious materials are better than those of wind power grouting materials prepared from silicate cement, and the improvement effect in various aspects is significant. By comparing grouting material examples 1-5, it can be found that grouting material example 5 has the best mechanical properties, fluidity and durability, mainly because activator 4 has both lubricating components, catalytic components, air entraining components, foam stabilizing components, and highly active components and nano-filling components. The synergy of multiple components not only improves fluidity, but also promotes hydration reaction, fills pores, improves mechanical properties, and improves durability. At the same time, the amount of modified tailings and ceramic polishing mud in grouting materials 1 to 5 is gradually increased, the components participating in hydration are gradually increased, and the mechanical properties are gradually improved.

[0054] Among grouting materials 6-7, grouting material 7 uses admixture 2, in which the amount of polycarboxylic acid water-reducing agent is higher, so the fluidity is greater, the amount of penetrating crystallization material is lower, and the antifreeze performance and sulfate corrosion resistance are worse.

[0055] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A solid waste-based marine engineering cementitious material, characterized in that: According to the mass proportion, it includes: modified tailings: 200-400 parts, ceramic polishing mud: 50-100 parts, fluorgypsum: 50-100 parts, red mud: 100-150 parts, activator: 10-30 parts, the modified tailings are modified by gold tailings fine powder, and the specific surface area of ​​the gold tailings fine powder is 300-350m 2 / kg, the modification process is as follows: first, the gold tailings fine powder is acidified in 10mol / L composite acid for 10min, the molar ratio of hydrochloric acid to citric acid in the composite acid is 1:1, and the ratio of gold tailings fine powder to composite acid is 10kg:1L; then, drying is performed, the dried gold tailings fine powder is mixed with carbide slag in a mass ratio of 10:1, and then ground in a ball mill until the specific surface area reaches 800-900m 2 / kg, and then the fine powder obtained by grinding is activated at 600-700℃ for 30min to obtain high-activity modified gold tailings powder. The cumulative mass percentage of SiO2, CaO and Al2O3 in the gold tailings fine powder is greater than 70%, and the specific surface area of ​​ceramic polishing mud is 900-1100m 2 / kg, the specific surface area of ​​fluorgypsum is 210-250m 2 / kg, the specific surface area of ​​red mud is 1100-1200m 2 / kg, the mass content of SiO2 in the ceramic polishing mud is above 90%; the activator includes a stabilizing component and an activating component in a mass ratio of (1-3): (30-90); the stabilizing component includes one or more of dibutyltin dilaurate, zinc stearate, antimony carboxylate, and phosphite; the activating component includes one or more of potassium silicate, lithium silicate, nano silicon powder, nano calcium oxide, and nano aluminum oxide.

2. The solid waste-based marine engineering cementitious material according to claim 1, characterized in that: Ceramic polishing mud has a specific surface area of ​​1000-1100m 2 / kg, the specific surface area of ​​fluorgypsum is 230-250m 2 / kg, the specific surface area of ​​red mud is 1150-1200m 2 / kg, the mass content of NaO in the red mud does not exceed 9%; the mass ratio of the stabilizing component to the stimulating component of the stimulator is 2:60; the stabilizing component includes a mass ratio of (1-3): (1-3):(0.5-1.5):(1-3) dibutyltin dilaurate, zinc stearate, antimony carboxylate, and phosphite; the exciting components include potassium silicate, lithium silicate, nano-silicon powder, nano-calcium oxide, and nano-aluminum oxide in a mass ratio of (1-2):(1-2):(2-3):(2-3):(0.5-1).

3. The solid waste-based marine engineering cementitious material according to claim 2, characterized in that: The gelling material comprises, by mass, 400 parts of modified tailings, 100 parts of ceramic polishing mud, 100 parts of fluorgypsum, 150 parts of red mud and 15 parts of activator; In the stimulator, the mass ratio of the stabilizing component to the stimulating component is 2.1:66, the stabilizing component includes dibutyltin dilaurate, zinc stearate, antimony carboxylate, and phosphite in a mass ratio of 1:1:0.5:1; the stimulating component includes potassium silicate, lithium silicate, nano silicon powder, nano calcium oxide, and nano aluminum oxide in a mass ratio of 2:2:3:3:

1.

4. A method for preparing a solid waste-based marine engineering cementitious material according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1. The modified tailings, ceramic polishing mud, fluorgypsum, red mud and the excitation component are mixed uniformly by a mixer to obtain a basic cementitious material A; S2, homogenizing material A through a high-pressure homogenizer, wherein the pressure of the high-pressure homogenizer is between 100 and 500 atmospheres, to obtain a reinforced gelling material B; S3. Evenly mix the reinforced cementitious material B and the stabilizing component to obtain a finished solid waste-based marine engineering cementitious material.

5. The method for preparing solid waste-based marine engineering cementitious materials according to claim 4, characterized in that: The pressure of the high pressure homogenizer is between 400 and 500 atmospheres.

6. An offshore wind power grouting material, characterized in that: The invention comprises a cementitious material, an aggregate, an admixture and water; the cementitious material is the solid waste-based marine engineering cementitious material as claimed in any one of claims 1 to 3; in the grouting material, the mass ratio of the cementitious material, the aggregate and the admixture is (4-6): (3-6): (0.02-0.25), the mass of the water is 0.17-0.22 times the mass of the gelling material.

7. An offshore wind power grouting material, characterized in that: The invention comprises cementitious material, aggregate, admixture and water; the cementitious material is a solid waste-based marine engineering cementitious material prepared by the preparation method of solid waste-based marine engineering cementitious material as claimed in claim 4; in the grouting material, the mass ratio of the cementitious material, aggregate and admixture is (4-6):(3-6):(0.02-0.25), and the mass of the water is 0.17-0.22 times the mass of the cementitious material.

8. The offshore wind power grouting material according to claim 7, characterized in that: The aggregate is machine-made sand prepared from tunnel slag, with a fineness modulus of 3.0-3.3; the admixture includes the following components by weight: 2-3 parts of polycarboxylic acid high-performance water reducer, 0.1-0.3 parts of silicone defoamer, and 1-3 parts of infiltration crystallization material.

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