Method for curing cement concrete product through CO2 reverse carbonization

Abstract

The invention relates to a method for curing a cement concrete product through CO2 reverse carbonization. The method comprises the following steps that S1, a through communicating hole channel is formed in the cement concrete product to be cured; s2, the cement concrete product is placed in a carbonization kettle, and vacuumizing treatment is carried out; s3, CO2 is injected from holes in the two ends of the communicating pore channel, the CO2 is reversely diffused and permeated in the communicating pore channel, and the cured product is carbonized; cO2 is reversely diffused and permeated to the surface and the periphery of the product from the communicating pore channels to form a forward carbonization curing atmosphere; and S4, after carbonization maintenance is finished, the communicating hole channels are filled. According to the method, CO2 is diffused, permeated and cured from the interior of the product to the surface of the product and continuously diffused to the surface and the periphery of the product to form a CO2 forward curing atmosphere, and complete and uniform carbonization of the product is achieved under the combined action of a reverse-forward dual curing mechanism.

Description

Technical Field

[0001] The invention relates to the field of cement concrete curing, and more specifically to a method for curing cement concrete products by reverse carbonization of CO2. Background Art

[0002] With the national "dual carbon" strategic goal and the requirement for sustainable development of the cement concrete industry, carbonation curing of cement concrete products has become a hot topic in the industry. However, the existing technologies all place the products in an environment containing CO2, so that CO2 diffuses and penetrates from the surface of the product to the inside (defined as forward diffusion and penetration) to form a carbonation curing mechanism. However, the existing forward carbonation curing mechanism has the disadvantages of low carbonization degree, uneven carbonization, low carbonization intensity, low carbon fixation rate, small scale of carbonized products, and single product structure. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for CO2 reverse carbonation curing of cement concrete products, which utilizes CO2 to diffuse from the inside of the product to the surface for penetration curing, and continuously diffuses to the surface of the product and its surroundings to form a CO2 forward curing atmosphere. The reverse-forward dual curing mechanisms work together to achieve complete and uniform carbonization of the product.

[0004] The technical solution adopted by the present invention to solve the technical problem is: constructing a method for curing cement concrete products by reverse carbonization of CO2, comprising the following steps:

[0005] S1. A connecting channel is provided inside the cement concrete product to be cured;

[0006] S2, placing the cement concrete product in a carbonization kettle and performing a vacuum treatment;

[0007] S3, injecting CO2 from the holes at both ends of the connected pores, CO2 diffuses and penetrates in the connected pores in the reverse direction to carbonize and cure the product; CO2 diffuses and penetrates from the connected pores in the reverse direction to the surface and surrounding of the product to form a positive carbonization curing atmosphere;

[0008] S4. After carbonization curing is completed, fill the connecting channels.

[0009] According to the above scheme, step S3 includes the following steps:

[0010] S41, filling reinforcing ribs in the connecting channels;

[0011] S42, injecting a micro-expansion grouting material into the communicating channel from the hole at one end of the communicating channel until the grouting material overflows from the hole at the other end;

[0012] S43, sealing the holes at both ends of the communicating channel to prevent the grouting material from flowing out, thereby obtaining a finished carbonized cement concrete product.

[0013] According to the above scheme, the interconnected channels are in the form of single channels, multiple channels or multiple channels cross-linked.

[0014] According to the above scheme, the CO2 injected in step S3 is in gaseous or liquid state.

[0015] According to the above scheme, the CO2 injection pressure in step S3 is 0MPa-1.5MPa.

[0016] According to the above solution, the reinforcing bars are steel bars, metal reinforcing bars, glass fiber bars, plastic bars or inorganic fiber bars.

[0017] According to the above scheme, in the step S1, the connecting channel forms at least two holes on the surface of the cement concrete product that are horizontal or have a certain height difference and distance.

[0018] The CO2 reverse carbonization curing cement concrete product method of the present invention has the following beneficial effects:

[0019] 1. The present invention constructs interconnected channels of different forms inside cement concrete products in a directional manner. After CO2 is injected, CO2 can diffuse and penetrate from the inside of the product to the outside for carbonization curing, i.e., reverse diffusion and penetration; CO2 continues to diffuse from the inside to the outside to the surface and surrounding of the product, and then forms a positive carbonization curing atmosphere. The reverse-positive carbonization curing mechanism enables the product to obtain complete and uniform carbonization performance, with a high carbon fixation rate, and can break through the limitations of product size and structural form, realizing carbon absorption curing of large-scale products.

[0020] 2. The present invention fills reinforcing ribs or reinforcing fibers and other materials inside the duct, and then injects grouting materials, which further improves the performance and stability of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0022] Figure 1 It is a schematic diagram of a method for curing cement concrete products by reverse carbonation of CO2;

[0023] Figure 2 It is a schematic diagram of the penetration of filling materials;

[0024] Figure 3 It is a schematic diagram of another embodiment of the channel directional structure. DETAILED DESCRIPTION

[0025] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0026] like Figures 1 to 3As shown, the CO2 reverse carbonization curing method for cement concrete products of the present invention comprises the following steps:

[0027] S1. A penetrating directional structural connecting channel 2 is arranged inside the cement concrete product 1. The channel 2 forms a first hole 3 and a second hole 4 on the surface of the product, which include at least two horizontal holes or holes with a certain height difference and distance. The connecting channel 2 is filled with reinforcing bars and micro-expansion grouting materials.

[0028] S2, placing the cement concrete product 1 in a carbonization kettle and performing a vacuum treatment;

[0029] S3, injecting CO2 from the first hole 3 and the second hole 4 on the surface of the cement concrete product 1. CO2 diffuses and penetrates 5 in the connected pores 2 to carbonize and cure the cement concrete product. CO2 continues to diffuse and penetrate from the pores to the surface of the product and the surroundings to form a positive carbonization curing atmosphere 6;

[0030] S4. After the carbonization curing is completed, reinforcing bars are filled in the communicating channel 2 and micro-expansion grouting material is injected. The first hole 3 and the second hole 4 are blocked to prevent the grouting material from flowing out, and a carbonized cement concrete product is obtained.

[0031] Preferably, the interconnected channels 2, the first holes 3 and the second holes 4 in step S1 include but are not limited to the directional structural forms shown in the drawings, including single channels, multiple channels and multiple channel cross-linked forms.

[0032] Preferably, the connecting channel 2 is formed on the surface of the product and includes at least two first holes 3 and second holes 4 at the same level or with a certain height difference and distance.

[0033] Preferably, the CO2 in step S3 is in gaseous or liquid state, and the CO2 injection pressure is 0 MPa-1.5 MPa.

[0034] Preferably, the reinforcing bars in step S4 include but are not limited to steel bars, metal reinforcing bars, glass fiber bars, plastic bars, and inorganic fiber bars.

[0035] Preferably, the strength of the micro-expansion grouting material in step S5 is higher than the carbonization strength of the product 1 .

[0036] The present invention adopts the above method to directionally construct different forms of connecting channels 2 inside the cement concrete product. After CO2 is injected, CO2 can diffuse and penetrate 5 from the inside of the product to the outside for carbonization curing; after CO2 continues to diffuse 5 to the surface and surrounding of the product, a positive carbonization curing atmosphere 6 is formed. The reverse-positive carbonization curing mechanism enables the product to obtain complete and uniform carbonization performance, high carbon fixation rate, and can break through the limitations of product scale and structural form to achieve carbon absorption curing of large-scale products. Filling the connecting channel 2 with materials such as reinforcing ribs or reinforcing fibers and then injecting grouting materials further improves the performance and stability of the product.

[0037] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation modes, which are merely illustrative rather than restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are within the protection of the present invention.

Claims

1. A method for curing cement concrete products by reverse carbonization of CO2, characterized in that: The following steps are involved: S1. A connecting channel is provided inside the cement concrete product to be cured; S2, placing the cement concrete product in a carbonization kettle and performing a vacuum treatment; S3, injecting CO2 from the holes at both ends of the connected pores, CO2 diffuses and penetrates in the connected pores in the reverse direction to carbonize and cure the product; CO2 diffuses and penetrates from the connected pores in the reverse direction to the surface and surrounding of the product to form a positive carbonization curing atmosphere; S4. After carbonization curing is completed, fill the connecting channels.

2. The CO2 reverse carbonization curing cement concrete product method according to claim 1, characterized in that: The step S3 comprises the following steps: S41, filling reinforcing ribs in the connecting channels; S42, injecting a micro-expansion grouting material into the communicating channel from the hole at one end of the communicating channel until the grouting material overflows from the hole at the other end; S43, sealing the holes at both ends of the communicating channel to prevent the grouting material from flowing out, thereby obtaining a finished carbonized cement concrete product.

3. The CO2 reverse carbonization curing cement concrete product method according to claim 1, characterized in that: The interconnected pores are in the form of single pores, multiple pores or multiple pores cross-linked.

4. The CO2 reverse carbonization curing cement concrete product method according to claim 1, characterized in that: The CO2 injected in step S3 is in gaseous or liquid state.

5. The CO2 reverse carbonization curing cement concrete product method according to claim 1, characterized in that: The CO2 injection pressure in step S3 is 0MPa-1.5MPa.

6. The CO2 reverse carbonization curing cement concrete product method according to claim 2, characterized in that: The reinforcing bars are steel bars, metal reinforcing bars, glass fiber bars, plastic bars or inorganic fiber bars.

7. The method for curing cement concrete products by CO2 reverse carbonization according to claim 1, characterized in that: In the step S1, the connecting channel forms at least two holes on the surface of the cement concrete product that are horizontal or have a certain height difference and distance.

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