Fabricated carbon sequestration ecological fish reef based on CO2 mineralized recycled aggregate and preparation method of fabricated carbon sequestration ecological fish reef

Abstract

The invention provides a fabricated carbon sequestration ecological fish reef based on CO2 mineralized recycled aggregate and a preparation method of the fabricated carbon sequestration ecological fish reef, and belongs to the technical field of carbon sequestration technologies and the field of marine ecological restoration. The fabricated carbon sequestration ecological fish reef based on the CO2 mineralized recycled aggregate is prepared from the following raw materials in parts by mass: 20 to 30 parts of CO2 mineralized recycled aggregate, 15 to 20 parts of sea sand, 10 to 15 parts of cement, 1 to 2 parts of mineral admixture, 2 to 4 parts of shell powder, 0.15 to 0.6 part of additive and 3 to 6 parts of water, the CO2 mineralized recycled aggregate is prepared from the following raw materials in parts by mass: 15 to 20 parts of CO2 mineralized recycled coarse aggregate and 5 to 10 parts of CO2 mineralized recycled fine aggregate. The fabricated carbon sequestration ecological fish reef based on the CO2 mineralized recycled aggregate is integrally formed through a formwork pouring process, and has the advantages of modular assembly, good stability, convenience in construction and the like. According to the method, marine ecological restoration and biological inhabitation are facilitated, carbon sequestration and emission reduction can be achieved through the CO2 mineralization technology, and high ecological and environmental protection values are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon fixation technology and the field of marine ecological restoration, and in particular to an assembled carbon fixation ecological fish reef based on CO2 mineralized recycled aggregate and a preparation method thereof. Background Art

[0002] With the acceleration of urbanization, a large amount of construction waste, including concrete, bricks, stones, waste wood, metal, etc., is generated during building demolition and new construction. At present, the treatment of construction waste mainly relies on landfill and stacking, which not only occupies a large amount of land resources, but also may cause serious pollution to the soil and groundwater. In order to reduce environmental pollution and waste of resources, the resource utilization of construction waste has become an important solution. Converting construction waste into reusable building materials through technical means can not only effectively reduce the amount of waste, but also save natural resources. However, the current resource utilization rate of construction waste in my country is less than 10%, and there is still much room for improvement in harmlessness, reduction and resource utilization.

[0003] Carbon capture, utilization and storage (CCUS) is one of the important means to address climate change, aiming to reduce the emission of greenhouse gases such as CO2. Carbon sequestration prevents the release of collected CO2 into the atmosphere by storing it in geological structures or other containers, while CO2 mineralization is an efficient carbon fixation method that converts gaseous CO2 into a solid state. This technology generates stable carbonates by reacting CO2 with minerals (such as silicates or carbonates of calcium and magnesium) to achieve long-term storage of CO2. CO2 mineralization technology has the advantages of high carbon fixation efficiency and good product stability, and has been widely used in cement production and slag treatment. Applying this technology to construction waste treatment can not only realize the resource utilization of solid waste, but also achieve carbon reduction goals, helping to build a "zero-waste city" and achieve the "dual carbon" goals.

[0004] Ecological fish reefs are hydraulic structures placed in the ocean and freshwater areas after scientific site selection. A large number of microorganisms and algae can be attached to the surface, providing a suitable biological habitat for local waters. Ecological fish reefs help protect marine life, improve the ecological environment of the sea area and promote the recovery of marine resources. The existing ecological fish reef construction mainly relies on reinforced concrete, stones and abandoned vehicles and ships to form box-shaped, triangular, frame-shaped and other structures. For example, the Chinese invention patent application with application number 202311556258.5 and the Chinese utility model patent with application number 202122219016.X. However, these traditional materials have the problems of high transportation costs, waste of resources and poor ecological adaptability. In addition, the high pH value and smooth surface of ordinary Portland cement are not conducive to the attachment of algae and marine organisms, and lack affinity to the marine environment.

[0005] Ecological design is to imitate the form and function of natural organisms. When applied to the design of ecological fish reefs, it can significantly improve the ecological function of fish reefs. Through ecological design, the surface of fish reefs can better simulate the microenvironment of natural reefs, provide more attachment points for microorganisms, algae and other marine organisms, and thus promote the reconstruction and stability of the ecosystem. Ecological fish reefs can be designed with a variety of holes and channels to provide shelter and breeding space for fish. At the same time, through reasonable size and structural design, large predatory fish can be blocked, providing a safe habitat for small fish and young fish. In addition, the roughness and morphological complexity of the surface of the fish reef after ecological design are more in line with the attachment needs of marine organisms, which helps to improve the overall ecological affinity of the fish reef.

[0006] The construction of traditional fish reefs usually faces the problems of complex construction, high cost and lack of flexibility. As a modern construction technology, prefabricated structures not only improve construction efficiency but also reduce environmental disturbances by quickly assembling prefabricated components on site. The modular design of prefabricated fish reefs allows each fish reef unit to be connected and expanded like building blocks to form a diverse fish reef community. It is not only easy to transport and install, but also can be adjusted and combined according to actual ecological needs to ensure that the fish reefs can maintain stable and efficient ecological functions under different sea conditions. Through the application of prefabricated structures, the construction process of fish reefs is more environmentally friendly and economical, which helps to promote the widespread application of ecological restoration projects.

[0007] Therefore, in view of the above technical problems, it is particularly important to develop a carbon-fixing ecological fish reef that can effectively realize the resource utilization of construction waste and CO2 sequestration. In addition, the purpose of deploying ecological fish reefs is not limited to improving the marine ecological environment and the proliferation of marine organisms. If ecological fish reefs can be used as a carrier to transfer land construction waste to the ocean for sequestration, it will also be of great significance in promoting the cycle of land and sea carbon resources. Summary of the invention

[0008] The present invention aims to provide an assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate and a preparation method thereof. The overall structure is integrally formed and made through a template casting process to form a stable fish reef unit. In order to enhance the ecological function and construction convenience of the fish reef, in addition to the overall structure, the ecological affinity and modular assembly of the fish reef are also targetedly designed, which can solve the problems of low resource utilization of construction waste, poor ecological affinity of traditional fish reefs, and insufficient flexibility in fish reef construction.

[0009] The assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate includes the following raw materials, calculated by weight: 20-30 parts of CO2 mineralized recycled aggregate, 15-20 parts of sea sand, 10-15 parts of cement, 1-2 parts of mineral admixtures, 2-4 parts of shell powder, 0.15-0.6 parts of additives and 3-6 parts of water; the CO2 mineralized recycled aggregate includes the following raw materials, calculated by weight: 15-20 parts of CO2 mineralized recycled coarse aggregate and 5-10 parts of CO2 mineralized recycled fine aggregate.

[0010] Preferably, the CO2 mineralized regenerated aggregate is prepared by gas-solid dry mineralization, and the specific steps include: washing the crushed and screened regenerated aggregate to remove surface dust and impurities, and then placing it in a closed carbonization chamber, introducing CO2 gas with a purity of 50% to 80%, controlling the temperature to 25 to 30°C, the humidity to 60% to 80%, the pressure to 0.1 to 0.5 MPa, and the reaction time to 3 to 7 days. After the mineralization reaction is completed, the regenerated aggregate is dried to remove excess moisture and unreacted CO2 to obtain CO2 mineralized regenerated aggregate.

[0011] More preferably, the recycled aggregate includes construction waste such as waste concrete and bricks generated during building demolition and construction.

[0012] Preferably, the particle size of the CO2 mineralized regenerated coarse aggregate is 5-20 mm, and the particle size of the CO2 mineralized regenerated fine aggregate is 0.15-5 mm.

[0013] Preferably, the sea sand is sea sand that has been fully desalinated.

[0014] Preferably, the particle size of the sea sand is 0.25~0.35 mm.

[0015] Preferably, the cement is general purpose Portland cement.

[0016] Preferably, the mineral admixture includes silica fume, fly ash, phosphorus slag powder or natural zeolite powder.

[0017] Preferably, the shell powder is obtained by crushing and grinding discarded mussel shells, and has a particle size of 10 to 50 μm.

[0018] Preferably, the additive comprises a water reducing agent, a retarder, an expansion agent, a foaming agent or a foam stabilizer.

[0019] Preferably, the structure of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate is an overall symmetrical hollow cubic structure, and a plurality of through holes are arranged on each face of the cubic structure, and the center lines of the through holes are on the same straight line as the center lines of the through holes at corresponding positions on the opposite faces.

[0020] The overall structure of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate is symmetrically designed, and the through holes on each side and the diversion structure are symmetrical, which can effectively guide and circulate the water flow and facilitate the free movement of fish, thereby achieving fish habitat and shelter. This symmetry helps to evenly distribute the water flow, reduce the resistance of the structure in the underwater environment, and ensure that the fish reef remains stable under the action of waves and tides.

[0021] More preferably, the diameter of the through hole of the tetrahedral structure is 100-150 mm, 180-220 mm or 280-320 mm.

[0022] Through holes with a diameter of 100~150 mm are suitable for small fish, providing them with shelter; holes with a diameter of 180~220 mm are suitable for medium-sized fish; holes with a diameter of 280~320 mm are suitable for larger fish, thereby achieving the habitat and shelter of different fish.

[0023] In the present invention, the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate usually adopts a unified aperture design. On the one hand, such a design facilitates the standardization of mold manufacturing and construction technology, reducing complexity; on the other hand, the unified aperture can better adapt to fish of a specific size, eliminate interference from large fish, and provide a safe shelter space for small fish.

[0024] The apertures of the assembled carbon-fixing ecological fish reefs based on CO2 mineralized recycled aggregates can also be inconsistent. This design can accommodate more species and sizes of fish, improve the ecological diversity of the fish reefs, and simulate a complex habitat that is closer to the natural environment. However, large fish may enter the reef through larger apertures, interfering with or threatening the shelter effect of small fish; in addition, different apertures may change water flow and shading effects, affecting the overall function of the reef.

[0025] Further preferably, the outer surface of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate is mounted with seaweed, adhered with shells and / or adhered with a bionic adhesion matrix.

[0026] The seaweed is mounted on the outer surface of the fish reef to simulate the natural habitat, thereby improving the ecological attractiveness of the fish reef. The selected seaweed adapts to the local marine environment, has good biocompatibility, and can effectively provide the shelter function and ecological benefits of natural seaweed. The seaweed mounting method uses a marine environmentally friendly adhesive to bond the roots or bases of the seaweed plants to the surface of the fish reef, ensuring that the seaweed is firmly attached and grows normally.

[0027] The shells are sourced from the beach and adhered to the surface of the reef using a marine environmentally friendly adhesive to increase the surface roughness, enhance the attachment effect of microorganisms and algae, and improve ecological affinity.

[0028] The bionic adhesive matrix is ​​a biodegradable adhesive that is attached to the surface of the fish reef by spraying or brushing. It can effectively increase the total amount of microorganisms and algae attached to the surface of the fish reef while withstanding the erosion of the marine environment.

[0029] It is further preferred that the prefabricated carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate is assembled using an interlocking structure, specifically, the four corners of the surface of one face in each group of opposite faces of the prefabricated carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate are respectively provided with protruding structures, and the corresponding positions of the four corners of the surface of the other face in each group of opposite faces are respectively provided with grooves matching the protruding structures.

[0030] The present invention designs the assembled fish reefs, which improves the functionality and stability of the assembled fish reefs through a flexible connection method, and at the same time provides convenience for the overall deployment of multiple fish reefs in the future. The assembled fish reef design adopts an interlocking structure to achieve a stable connection and flexible assembly between the fish reef monomers. Through this docking structure, the protruding structure can be accurately embedded in the pit structure of the adjacent monomer to form an efficient and stable connection. This design ensures that the connection between the monomers is more accurate, and can achieve automatic docking during the assembly process, significantly reducing the structural instability that may be caused by human errors or improper splicing. This interlocking design not only makes the splicing between the fish reef monomers easier and more stable, but also has strong adaptability and modular characteristics, which improves the convenience of construction of the fish reefs and the flexibility of later maintenance. Moreover, the combination of the fish reefs can be adjusted according to actual needs, and free stacking can be achieved in both the horizontal and vertical directions, so as to meet the ecological needs in different environments.

[0031] Further preferably, the top plate of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate is provided with lifting rings around it, and the contrast surface of the top plate is provided with a groove with an inner diameter larger than the lifting ring at the position corresponding to the lifting ring, and the inner diameter of the lifting ring groove is larger than the outer diameter of the lifting ring.

[0032] The method for preparing the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate comprises the following steps: S1. Weigh CO2 mineralized recycled coarse aggregate, CO2 mineralized recycled fine aggregate, sea sand, cement, mineral admixture and shell powder and mix them evenly to prepare a dry mixture; S2, weighing an additive and water, and adding the additive to the water to obtain a mixed solution, adding the mixed solution to the dry mixed material obtained in step S1, mixing evenly, to obtain a wet mixed material; S3, pouring the wet mixture prepared in step S2 into a mold, pressing and molding, and removing air to perform initial setting; S4, demoulding the fish reef initially solidified in step S3, and carrying out natural curing for a period of time to obtain the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate.

[0033] Preferably, the initial setting is carried out at room temperature, and the initial setting time is 10 to 24 hours.

[0034] Preferably, the natural curing is carried out at room temperature for 5 to 10 days.

[0035] Compared with the prior art, the beneficial effects of the present invention are: (1) The present invention effectively realizes the resource utilization of construction waste by preparing recycled aggregates from construction waste and applying them to the preparation of ecological fish reefs. This not only reduces dependence on natural resources and reduces the occupation of land resources by landfill, but also promotes the recycling of waste and helps promote sustainable environmental development.

[0036] (2) The present invention uses CO2 mineralization technology to store CO2 in recycled aggregates. This process not only reduces greenhouse gas emissions and achieves carbon sequestration, but also significantly improves the physical and chemical properties of recycled aggregates, making ecological fish reefs more durable and stable. In addition, this technology helps fish reefs maintain their structural integrity and functional effects in underwater environments for a long time.

[0037] (3) The fish reef prepared by the present invention through CO2 mineralization and strengthening of recycled aggregate has a surface pH value within an appropriate range (7.5-8.5) and has good compatibility with the marine environment. The incorporation of shell fragments as raw materials increases the roughness of the fish reef surface, thereby improving the fish reef's ability to attach algae and other marine organisms. These characteristics are conducive to establishing a healthy underwater ecosystem and improving the quality of the marine environment.

[0038] (4) The present invention realizes the marine storage of land waste by applying the construction waste after resource recovery to the construction of marine ecological fish reefs, thus expanding the role of the ocean as a carbon reservoir. This not only effectively promotes the carbon resource cycle between land and sea, helps to reduce the CO2 concentration in the atmosphere, but also supports the realization of the global carbon neutrality goal and the healthy development of the marine ecosystem.

[0039] (5) The ecological design of the fish reef in the present invention imitates the complex morphology of natural reefs, providing abundant attachment points for seaweed and other aquatic plants, thereby attracting fish and other marine life to inhabit. Through the diverse hole and channel design of the bionic structure, the fish reef can not only provide shelter and breeding space for small fish and juvenile fish, but also enhance the overall biological carbon fixation effect, further enhancing the support role of the fish reef to the ecosystem.

[0040] (6) The present invention adopts a modular prefabricated structural design, which can be quickly and flexibly assembled on site through prefabricated fish reef units. The interlocking mechanism between modules not only simplifies the transportation and installation process, but also allows the fish reef units to be adjusted and expanded according to actual environmental requirements. This prefabricated design significantly improves construction efficiency and reduces disturbance to the marine environment. At the same time, it enhances the ecological function of the fish reef community through a variety of combinations. The flexibility of modular assembly enables the fish reef to adapt to different water conditions and ecological requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a schematic diagram of the external structure of the assembled carbon fixation ecological fish reef based on CO2 mineralized recycled aggregate provided in Example 1; Figure 2 This is a cross-sectional view of the internal structure of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate provided in Example 1; Figure 3 This is a schematic diagram of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate provided in Example 1 after ecological design; Figure 4 The assembly process and assembly schematic diagram of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate provided in Example 2; In the figure: 1, is a hanging ring; 2, is a raised structure; 3, is a through hole; 4, is a groove; 5, is seaweed; 6, is a shell fragment. DETAILED DESCRIPTION

[0042] The technical scheme of the present invention is further described below by way of examples. The raw materials used in the examples can be purchased from the market or prepared by conventional methods.

[0043] Example 1 A prefabricated carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate, composed of the following raw materials: CO2 mineralized recycled coarse aggregate, CO2 mineralized recycled fine aggregate, sea sand, cement, mineral admixture, shell fragments, additives and water, the mass ratio of CO2 mineralized recycled coarse aggregate: CO2 mineralized recycled fine aggregate: sea sand: cement: mineral admixture: shell fragments: additives: water is 30:12:25:20:3:5:0.6:7; the particle size of the sea sand is 0.30 mm, and is fully desalinated before use; the cement is general silicate cement; the mineral admixture is fly ash; the shell fragments are obtained by crushing discarded mussel shells near the coastline, and the additive is a water reducer; the CO2 mineralized regenerated coarse aggregate and CO2 mineralized regenerated fine aggregate are mineralized by gas-solid dry method, and the specific steps are as follows: the abandoned concrete, bricks and other construction waste generated during the demolition and construction of the building are crushed and screened by a jaw crusher, and the screened regenerated aggregate is cleaned to remove surface dust and impurities, and then placed in a closed carbonization chamber, and industrial CO2 gas with a purity of 60% is introduced, the temperature is controlled at 28°C, the humidity is 70%, the pressure is 0.3 Mpa, the reaction time is 7 days, and after the mineralization reaction is completed, the regenerated aggregate is dried to remove excess water and unreacted CO2, and finally the CO2 mineralized regenerated coarse aggregate and CO2 mineralized regenerated fine aggregate are obtained; the particle size of the CO2 mineralized regenerated coarse aggregate is 5~20 mm, and the particle size of the CO2 mineralized recycled fine aggregate is 0.15~5 mm.

[0044] The assembled bionic carbon-fixing fish reef based on CO2 mineralized recycled aggregate is as follows: Figure 1 to Figure 2 As shown, the overall structure is an overall symmetrical hollow cubic structure, and a plurality of through holes are arranged on each face of the cubic body, and the center lines of the through holes are on the same straight line as the center lines of the through holes at the corresponding positions on the opposite faces; the aperture of the through holes is 125 mm; the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregates is assembled using an interlocking structure, specifically, the four corners of the surface of one face in each group of opposite faces of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregates are respectively provided with protruding structures, and the corresponding positions of the four corners of the surface of the other face in each group of opposite faces are respectively provided with grooves matching the protruding structures; the top plate of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregates is provided with lifting rings around it, and the contrasting surface of the top plate is provided with a groove with an inner diameter larger than the lifting ring at the position corresponding to the lifting ring, and the inner diameter of the lifting ring groove is larger than the outer diameter of the lifting ring.

[0045] This embodiment designs the fish reef ecologically by mounting natural seaweed and adhering discarded shell fragments or bionic adhesive matrix to the surface of the assembled bionic carbon-fixing fish reef based on CO2 mineralized recycled aggregate. Figure 3 As shown, the ecological function of fish reefs can be enhanced to attract more fish to inhabit and reproduce.

[0046] The overall structure of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate is symmetrically designed, and the through holes on each side and the diversion structure are symmetrical, which can effectively guide and circulate the water flow and facilitate the free movement of fish, thereby achieving fish habitat and shelter. This symmetry helps to evenly distribute the water flow, reduce the resistance of the structure in the underwater environment, and ensure that the fish reef remains stable under the action of waves and tides. Setting the through hole diameter on the surface of the fish reef to 125 mm can provide a good shelter space for fish of these sizes.

[0047] The assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate is prepared by the following steps: S1, weigh the selected amount of each raw material component and set aside; S2, mixing the dry materials in the above-mentioned raw materials, i.e., CO2 mineralized regenerated coarse aggregate, CO2 mineralized regenerated fine aggregate, sea sand, cement, mineral admixtures and shell powder, and fully stirring them using a concrete mixer; S3, adding the additive to water and stirring thoroughly, then adding the mixture to the uniform dry mixture in step S2, stirring thoroughly to obtain a wet mixture; S4, pouring the wet mixture in step S3 into a mold, pressing and molding, removing air, and performing initial setting of the structure for 12 hours; S5. De-mould the initially formed fish reef and carry out natural curing for 7 days to finally obtain an assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate.

[0048] The assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate provided in this embodiment is applied to the waters of Hainan. The coastal waters of Hainan Province have moderate water depth, high water temperature, rich ecosystem, and are mainly inhabited by various small fish and shellfish. The sea environment in the specific deployment area is relatively flat, the seabed geology is relatively uniform, and the water flow is relatively gentle. This kind of environment is suitable for creating ecological fish reefs that mainly shelter small fish, which helps maintain ecological balance and promote the diversity of aquatic species.

[0049] In the Hainan waters where the assembled carbon fixation ecological fish reef based on CO2 mineralized recycled aggregate described in this embodiment is placed, the fish that need to be sheltered in the habitat are mainly luminous porgy, yellow-spotted bream, silver perch, etc. The natural seaweed is selected from sea calamus, which is mounted on the outer surface of the fish reef to simulate the natural habitat, thereby improving the ecological attractiveness of the fish reef. Sea calamus adapts to the local marine environment, has good biocompatibility, and can effectively provide the shelter function and ecological benefits of natural seaweed. The sea calamus mounting method uses a marine environmentally friendly adhesive to bond the roots or bases of the seaweed plants to the surface of the fish reef to ensure that the seaweed is firmly attached and grows normally. The broken shells come from the beach, are crushed into 10~20mm fragments by a crusher, and are evenly adhered to the surface of the fish reef to increase its surface roughness and enhance the attachment effect of microorganisms and algae. The added bionic adhesion matrix is ​​a biodegradable bio-based adhesive alginate, which is attached to the surface of the fish reef by spraying, and can effectively increase the total amount of microorganisms and algae attached to the surface of the fish reef while tolerating the erosion of the marine environment.

[0050] In this embodiment, the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate is placed in the coastal area of ​​Hainan, and the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate is placed as a single body to ensure that the seabed arrangement position of the fish reef can be flexibly adjusted during the placement process, so as to maximize the use of the sea space. During the placement of the fish reef, the GPS positioning system is usually used to ensure the accurate positioning of the placement point. First, the fish reef is transported to the top of the predetermined sea area and accurately positioned by GPS to confirm the correct position. Then, the fish reef is lifted vertically using the lifting equipment on the ship and slowly lowered to the bottom of the designated placement point. As the fish reef gradually sinks, the lowering speed is controlled to ensure the stable placement of the fish reef. Throughout the process, verticality and position stability are maintained to prevent the displacement of the fish reef by the water flow, so as to achieve accurate and stable placement of the fish reef on the seabed.

[0051] In terms of carbon sequestration benefits, the assembled carbon sequestration ecological fish reef based on CO2 mineralized recycled aggregate described in this embodiment can bring significant carbon sequestration benefits through carbon sequestration. In this embodiment, the overall structure of the ecological fish reef is a cube with a side length of 2 m, and the amount of concrete used for each fish reef unit is 2.7 m 3, the weight of the single unit is 6.5 t. According to the preparation process of carbon-fixing concrete, the unit volume of carbon-fixing concrete in this embodiment can store about 250 kg of CO2, so each fish reef unit can store about 675 kg of CO2. In this embodiment, a total of 120 fish reef units were put into the fish reef group, and a total of about 81,000 kg of CO2 was stored. This carbon fixation benefit not only helps to mitigate climate change, but also further enhances the environmental value of ecological fish reefs, and contributes to the restoration of coastal ecosystems and carbon neutrality goals. As mentioned above, the water grass attached to the surface of the fish reef through the bioadhesive matrix in this implementation is sea calamus, which adapts to the marine environment of Hainan waters and can grow naturally on the surface of the fish reef. It can be seen from the marine carbon sink related database that the annual carbon fixation factor of the sea calamus grass bed is 0.733 kg / m 2 The single reef has 5 surfaces (except the bottom) covered with sea calamus, so the total paving area is 20 m 2 The annual carbon sequestration of aquatic plants on a single fish reef can reach 14.66 kg CO2, so the total carbon fixation of the 120 fish reefs in the fish reef group is 1759.2 kg CO2.

[0052] Example 2 An assembled bionic carbon-fixing fish reef based on CO2 mineralized recycled aggregate is consistent with the assembled bionic carbon-fixing fish reef based on CO2 mineralized recycled aggregate in Example 1, with the only difference being that the through hole diameter is 200 mm.

[0053] The assembled bionic carbon-fixing fish reef based on CO2 mineralized recycled aggregate described in this embodiment is applied in the waters of Dalian. According to the size of the main economic fish in the waters of Dalian, the fish that need to be sheltered in the habitat are mainly small yellow croaker, high-eye flounder, long-eyed bream, big-tailed six-line fish and Xu's flatfish, etc. In order to ensure that they can pass through the through holes smoothly, the through hole diameter of the surface of the assembled bionic carbon-fixing fish reef based on CO2 mineralized recycled aggregate is set to 200 mm, which can provide good shelter space for fish of these sizes.

[0054] The seagrass mounted on the surface of the assembled bionic carbon-fixing fish reef based on CO2 mineralized recycled aggregate described in this embodiment is eelgrass to simulate the natural habitat, thereby improving the ecological attractiveness of the fish reef. Eelgrass is adapted to the environment of Dalian sea area, has good biocompatibility, and can effectively provide the shelter function and ecological benefits of natural seagrass. The eelgrass mounting method uses a marine environmentally friendly adhesive to bond the roots or bases of the seagrass plants to the surface of the fish reef, ensuring that the seagrass is firmly attached and grows normally.

[0055] The assembled bionic carbon-fixing fish reef based on CO2 mineralized recycled aggregate described in this embodiment is four-in-one. Through the interlocking structure, the protruding structure can be accurately embedded in the groove structure of the adjacent assembled bionic carbon-fixing fish reef based on CO2 mineralized recycled aggregate, forming an efficient and stable connection, forming a plane robust configuration, such as Figure 4 As shown, it provides convenience for the subsequent overall deployment of multiple fish reefs. This configuration can effectively cope with external forces such as water flow and waves in the marine environment of Dalian waters, maintain the stability and functionality of the fish reefs, ensure that they can provide long-term shelter and provide a stable habitat for fish.

[0056] In terms of carbon fixation benefits, in this embodiment, each assembled bionic carbon fixation fish reef monomer based on CO2 mineralized recycled aggregate can store about 675 kg of CO2. In this embodiment, a total of 53 assembled fish reefs were deployed in the fish reef group, which stored a total of about 143,100 kg of CO2. The water grass attached to the surface of the fish reef through the bioadhesive matrix in this embodiment is eel grass, which adapts to the marine environment of Dalian waters and can grow naturally on the surface of the fish reef. It can be seen from the marine carbon sink related database that the annual carbon fixation factor of eel grass is 1.83 kg / m 2 The fabricated fish reef is only covered with eelgrass on the top surface, so the total paving area is 16 m 2 , the carbon sequestration of aquatic plants on a fabricated fish reef can reach 29.28 kg CO2 per year, so the total carbon sequestration of 53 fabricated fish reefs in the fish reef group is 1551.84 kg CO2. The ecological fish reef described in this embodiment, after the four fish reef monomers are assembled in a fabricated manner, forms a flat and robust configuration.

[0057] It should be understood that the above embodiments are only used to illustrate the present invention and are not used to limit the scope of protection of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

Claims

1. An assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate, characterized in that: The raw materials include, by weight: 20-30 parts of CO2 mineralized recycled aggregate, 15-20 parts of sea sand, 10-15 parts of cement, 1-2 parts of mineral admixture, 2-4 parts of shell powder, 0.15-0.6 parts of additives and 3-6 parts of water; the CO2 mineralized recycled aggregate includes, by weight: 15-20 parts of CO2 mineralized recycled coarse aggregate and 5-10 parts of CO2 mineralized recycled fine aggregate.

2. The assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate according to claim 1, characterized in that: The CO2 mineralized recycled aggregate is prepared by gas-solid dry mineralization, and the specific steps include: washing the crushed and screened recycled aggregate to remove surface dust and impurities, placing it in a closed carbonization chamber, introducing CO2 gas with a purity of 50% to 80%, controlling the temperature to 25 to 30°C, the humidity to 60% to 80%, the pressure to 0.1 to 0.5 MPa, and the reaction time to 3 to 7 days. After the mineralization reaction is completed, the recycled aggregate is dried to remove excess moisture and unreacted CO2 to obtain CO2 mineralized recycled aggregate.

3. The assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate according to claim 1 is characterized in that: The particle size of the CO2 mineralized regenerated coarse aggregate is 5~20 mm, and the particle size of the CO2 mineralized regenerated fine aggregate is 0.15~5 mm; the sea sand is sea sand that has been desalinated; the particle size of the sea sand is 0.25~0.35 mm; the cement is general-purpose silicate cement; the mineral admixture includes silica fume, fly ash, phosphate slag powder or natural zeolite powder; the shell powder is obtained by crushing and grinding discarded mussel shells, and has a particle size of 10~50μm; the additives include water reducers, retarders, expansion agents, foaming agents or foam stabilizers.

4. The assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate according to claim 1 is characterized in that: The structure of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate is an overall symmetrical hollow cubic structure, and a plurality of through holes are arranged on each face of the cubic structure, and the center lines of the through holes are on the same straight line as the center lines of the through holes at corresponding positions on the opposite faces.

5. The assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate according to claim 4 is characterized in that: The through holes of the tetrahedral structure have a diameter of 100-150 mm, 180-220 mm or 280-320 mm.

6. The assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate according to claim 4 is characterized in that: The outer surface of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate is mounted with seaweed, adhered with shells and / or adhered with a bionic adhesion matrix.

7. The assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate according to claim 4 is characterized in that: The assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate is assembled using an interlocking structure. Specifically, the four corners of the surface of one face in each set of opposite faces of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate are respectively provided with protruding structures, and the corresponding positions of the four corners of the surface of the other face in each set of opposite faces are respectively provided with grooves matching the protruding structures.

8. The assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate according to claim 4 is characterized in that: The top plate of the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate is provided with lifting rings around it, and the contrast surface of the top plate is provided with a groove with an inner diameter larger than the lifting ring at the position corresponding to the lifting ring, and the inner diameter of the lifting ring groove is larger than the outer diameter of the lifting ring.

9. A method for preparing an assembled carbon-fixing ecological fish reef based on CO2 mineralized regenerated aggregate according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Weigh CO2 mineralized recycled coarse aggregate, CO2 mineralized recycled fine aggregate, sea sand, cement, mineral admixture and shell powder and mix them evenly to prepare a dry mixture; S2, weighing an additive and water, and adding the additive to the water to obtain a mixed solution, adding the mixed solution to the dry mixed material obtained in step S1, mixing evenly, to obtain a wet mixed material; S3, pouring the wet mixture prepared in step S2 into a mold, pressing and molding, and removing air to perform initial setting; S4, demoulding the fish reef initially solidified in step S3, and carrying out natural curing for a period of time to obtain the assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate.

10. The method for preparing an assembled carbon-fixing ecological fish reef based on CO2 mineralized recycled aggregate according to claim 9, characterized in that The initial setting is carried out at room temperature, and the initial setting time is 10 to 24 hours; the natural curing is carried out at room temperature, and the curing time is 5 to 10 days.

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