Device and method for cooperatively treating solid waste concrete by using seawater and carbon dioxide

Abstract

The invention relates to the technical field of building materials, and discloses a device and method for cooperatively treating solid waste concrete through seawater and carbon dioxide, the device comprises a low-temperature reaction tank, and solid waste and seawater are put into the low-temperature reaction tank; the cooling system comprises a gas cylinder and a low-temperature controller, the gas cylinder is communicated with the low-temperature reaction tank and used for conveying carbon dioxide gas into the low-temperature reaction tank, and the low-temperature controller is electrically connected with the low-temperature reaction tank; the heating system comprises a heating mold and a heating controller, solid waste is arranged in the heating mold, the heating mold is communicated with the low-temperature reaction tank through a control part, the control part is used for conveying a solution in the low-temperature reaction tank and external air into the heating mold, and the heating controller is electrically connected with the heating mold. According to the method, seawater and carbon dioxide are used for cooperatively treating the multi-source solid waste to prepare the pressure-free all-solid-waste concrete, carbon emission of the traditional cement industry is reduced, a new path is provided for high-value utilization of the multi-source solid waste and marine resources, and the method has remarkable environment-friendly and economic values.

Description

Technical Field

[0001] The present invention relates to the technical field of building materials, and in particular to a device and method for collaboratively treating solid waste concrete using seawater and carbon dioxide. Background Art

[0002] With the acceleration of global urbanization and the continued expansion of industrial production, the accumulation of multiple sources of solid waste, such as construction waste and industrial solid waste, is becoming increasingly serious. Traditional landfill or stacking methods not only consume land resources but also pose environmental risks. Furthermore, the continued increase in carbon emissions from the industrial and building materials sectors is exacerbating climate change, necessitating the urgent need for innovative carbon capture and resource utilization technologies.

[0003] Currently, the resource utilization of solid waste based on CO2 mineralization technology has been widely studied, primarily focusing on the carbonization modification of alkaline solid waste. Research has found that carbonization of alkaline solid waste can improve its applicability and stability in concrete systems. Existing technologies often use high-temperature calcination combined with pressing and carbonization processes, or chemical additives to promote the hydration reaction of solid waste particles through alkali stimulation, to produce all-solid waste concrete.

[0004] Existing related technologies require the combination of cement or chemical additives, or a high-temperature calcination and synergistic pressing molding process. There are generally problems such as low CO2 capture efficiency, difficulty in applying efficient solid waste, and insufficient product strength. In addition, magnesium ions, carbonate ions, and bicarbonate ions in seawater can serve as natural media for mineralization reactions, synergistically reacting with active components in solid waste to help form a stable carbonate interwoven network structure. However, related research is mostly limited to the regulation of calcium carbonate crystal structure at the microscopic scale, and the exploration of pressure-free, all-solid waste negative carbon concrete is still blank.

[0005] Therefore, there is an urgent need for a device and method for collaboratively treating solid waste concrete using seawater and carbon dioxide to solve the above problems. Summary of the Invention

[0006] The purpose of the present invention is to provide a device and method for collaboratively treating solid waste concrete using seawater and carbon dioxide, so as to solve the problems existing in the above-mentioned prior art.

[0007] To achieve the above-mentioned object, the present invention provides the following solution: The present invention provides a device for collaboratively treating solid waste concrete using seawater and carbon dioxide, comprising:

[0008] a low-temperature reaction tank, wherein solid waste and seawater are placed in the low-temperature reaction tank;

[0009] a cooling system comprising a gas cylinder and a cryogenic controller, wherein the gas cylinder is in communication with the cryogenic reaction tank and is used to deliver carbon dioxide gas into the cryogenic reaction tank, and the cryogenic controller is electrically connected to the cryogenic reaction tank;

[0010] The heating system includes a heating mold and a heating controller. Solid waste is set in the heating mold, and the heating mold is connected to the low-temperature reaction tank through a control component. The control component is used to transport the solution in the low-temperature reaction tank and the outside air into the heating mold. The heating controller is electrically connected to the heating mold.

[0011] According to a device for collaboratively treating solid waste concrete with seawater and carbon dioxide provided by the present invention, the control component includes a water pump and an air pump, the input end of the water pump is connected to the low-temperature reaction tank, and the output ends of the water pump and the air pump are respectively connected to the heating mold.

[0012] According to the present invention, a device for collaboratively treating solid waste concrete with seawater and carbon dioxide further includes a multi-channel intermittent controller, and the water pump and the air pump are electrically connected to the multi-channel intermittent controller respectively.

[0013] According to a device for collaboratively treating solid waste concrete with seawater and carbon dioxide provided by the present invention, the heating mold includes a copper tube and two joints, an electric heating wire is wound around the copper tube, a water inlet and an air inlet are provided on the upper joint, the water inlet is connected to the output end of the water pump, the air inlet is connected to the output end of the air pump, and a water outlet is provided on the lower joint.

[0014] According to the device for collaboratively treating solid waste concrete using seawater and carbon dioxide provided by the present invention, the concrete specimen is located in the copper tube, and filter screens are provided at both ends of the concrete specimen.

[0015] According to a device for collaboratively treating solid waste concrete with seawater and carbon dioxide provided by the present invention, the inner diameter of the copper tube is W=12 mm, the inner diameters of the water inlet, the air inlet, and the water outlet are all W2=6 mm, the length of the concrete specimen is W3=20 mm, and the length of the copper tube is W4=30 mm.

[0016] According to the present invention, a device for collaboratively treating solid waste concrete using seawater and carbon dioxide further includes a magnetic stirrer installed on the low-temperature reaction tank.

[0017] According to the device for collaboratively treating solid waste concrete using seawater and carbon dioxide provided by the present invention, the solid waste in the low-temperature reaction tank and the heating mold is at least one of steel slag, recycled aggregate, shell or coral.

[0018] According to the device for collaboratively treating solid waste concrete using seawater and carbon dioxide provided by the present invention, a flow meter is installed at the output end of the gas cylinder.

[0019] A method for synergistically treating solid waste concrete using seawater and carbon dioxide comprises the following steps:

[0020] The recycled aggregate is crushed into powder and mixed with seawater, and then added into a low-temperature reaction tank for mixing and stirring;

[0021] Open the gas cylinder and introduce carbon dioxide gas into the low-temperature reaction tank, and set the temperature in the low-temperature reaction tank to 1-5°C;

[0022] Place the solid waste into a heated mold and set the temperature to 60-80°C;

[0023] transporting the mixed solution in the low-temperature reaction tank to the heating mold to prepare a concrete specimen;

[0024] The concrete specimens were taken out for drying.

[0025] Compared with the prior art, the present invention has the following advantages and technical effects:

[0026] The present invention provides an apparatus and method for collaboratively treating solid waste concrete using seawater and carbon dioxide. Recycled aggregate and seawater are mixed and stirred in a low-temperature reaction tank, carbon dioxide gas is introduced through a provided gas cylinder, the temperature of the low-temperature reaction tank is controlled by a low-temperature controller, solid waste is placed in a heating mold, the temperature of the heating mold is controlled by a heating controller, and simultaneously, a control component controls the delivery of the solution in the low-temperature reaction tank and external gas into the heating mold to prepare concrete. The present application utilizes seawater and carbon dioxide to treat multi-source solid waste at low temperature to synthesize a carbonized cementitious solution, and then uses the carbonized cementitious solution to treat multi-source solid waste at high temperature to prepare all-solid waste concrete. The entire concrete preparation process does not require the combination of cement or chemical admixtures, is low-carbon and environmentally friendly, and has a high solid waste utilization rate. Seawater, multi-source solid waste and carbon dioxide are used as raw materials, which are abundant in resources, low in cost, and do not require the help of compression molding, effectively contributing to the coordinated development of the three-in-one utilization of ocean, solid waste resource utilization and carbon emission reduction. By utilizing magnesium ions, bicarbonate ions and carbonate ions in seawater to regulate the crystal structure of the mineralized product, it can not only effectively enhance the mechanical properties of pressure-free all-solid waste concrete, but also alleviate the negative ecological effects of seawater acidification. It realizes the dry-wet alternation of multi-source solid waste in the heated mold, thereby further accelerating the mineralization and cementation of multi-source solid waste in the heated mold. The present application utilizes seawater and carbon dioxide to synergistically treat multi-source solid waste to prepare pressure-free all-solid waste concrete, significantly reducing carbon emissions in the traditional cement industry, providing a new path for the high-value utilization of multi-source solid waste and marine resources, and has significant environmental and economic value. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive work.

[0028] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0029] Figure 2 This is a schematic diagram of the heating mold structure of the present invention;

[0030] Figure 3 The XRD patterns of Examples 1 and 2 of the present invention are shown in FIG.

[0031] Figure 4 This is a schematic diagram of thermogravimetric analysis of an embodiment of the present invention;

[0032] Figure 5 This is a schematic diagram of thermogravimetric analysis of Comparative Example 1 of the present invention;

[0033] Figure 6 This is a schematic diagram of thermogravimetric analysis of Comparative Example 2 of the present invention;

[0034] Among them, 1. Gas cylinder; 2. Low temperature controller; 3. Flow meter; 4. Low temperature reaction tank; 5. Water outlet; 6. Magnetic stirrer; 7. Water pump; 8. Air pump; 9. Multi-channel intermittent controller; 10. Heating mold; 11. Heating controller; 12. Concrete specimen; 13. Water inlet; 14. Air inlet; 15. Filter. DETAILED DESCRIPTION

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0036] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] Reference Figures 1-6 The present invention provides a device for collaboratively treating solid waste concrete using seawater and carbon dioxide, comprising:

[0038] A low-temperature reaction tank 4, in which solid waste and seawater are placed;

[0039] The cooling system includes a gas cylinder 1 and a cryogenic controller 2. The gas cylinder 1 is connected to the cryogenic reaction tank 4 and is used to transport carbon dioxide gas into the cryogenic reaction tank 4. The cryogenic controller 2 is electrically connected to the cryogenic reaction tank 4.

[0040] The heating system includes a heating mold 10 and a heating controller 11. Solid waste is set in the heating mold 10, and the heating mold 10 is connected to the low-temperature reaction tank 4 through a control component. The control component is used to transport the solution in the low-temperature reaction tank 4 and the outside air into the heating mold 10. The heating controller 11 is electrically connected to the heating mold 10.

[0041] In one embodiment of the present invention, the gas in gas cylinder 1 is at least one of carbon dioxide and air. To ensure that the gas is not affected by the solution pressure and can escape smoothly into the solution for full reaction, the gas flow rate is 0.05-0.4 L / min. If the gas flow rate is higher than 0.4 L / min, the pH value of the solution in low-temperature reaction tank 4 will be difficult to control. If the gas flow rate is lower than 0.05 L / min, the solution pressure will affect the gas flow rate and make it difficult for the gas to escape into the solution through the gas pipe.

[0042] In order to increase the solubility of calcium carbonate and thus improve the yield and stability of calcium bicarbonate, the solution temperature in the low-temperature reaction tank 4 is set to 1-5° C. and the pH value is controlled to 6-8.

[0043] In order to ensure that the solution in the low-temperature reaction tank completely penetrates through the multi-source solid waste in the heating mold and fully mineralizes and reacts and deposits, the multi-source solid waste in the heating mold is designed to have a porosity of 40%-60%.

[0044] In order to promote the transformation of calcium carbonate, a mineralization reaction product, into needle-shaped aragonite in the heated mold, the temperature of the heated mold is 60-80°C.

[0045] As an optional embodiment, the control component includes a water pump 7 and an air pump 8. The input end of the water pump 7 is connected to the low-temperature reaction tank 4, and the output ends of the water pump 7 and the air pump 8 are respectively connected to the heating mold 10.

[0046] In one embodiment of the present invention, the low-temperature reaction tank 4 is connected to the heating mold 10 via a water pump 7 , and external air is transported into the heating mold 10 via an air pump 8 .

[0047] As an optional embodiment, a multi-channel intermittent controller 9 is further included, and the water pump 7 and the air pump 8 are electrically connected to the multi-channel intermittent controller 9 respectively.

[0048] In one embodiment of the present invention, in order to establish a dry-wet alternating system on the surface of multi-source solid waste particles in a heating mold to increase the mineralization reaction rate of the multi-source solid waste surface, the intermittent parameters of the multi-channel intermittent controller 9 are: the water pump 7 is on for 3 hours and off for 0.5 hours, and the air pump 9 is off for 3 hours and on for 0.5 hours.

[0049] In order to ensure that the solution in the low-temperature reaction tank 4 is heated evenly and fully when passing into the heating mold 10, the water pump 7 controls the flow rate of the solution to be 0-3 mL / min.

[0050] In order to ensure that the multi-source solid waste particles in the heating mold 10 are fully dried, the gas flow rate of the air pump 8 is 3-18 L / min.

[0051] As an optional embodiment, the heating mold 10 includes a copper tube and two joints, an electric heating wire is wound on the copper tube, a water inlet 13 and an air inlet 14 are provided on the upper joint, the water inlet 13 is connected to the output end of the water pump 7, the air inlet 14 is connected to the output end of the air pump 8, and a water outlet 5 is provided on the lower joint.

[0052] As an optional implementation, the concrete specimen 12 is located in the copper tube, and filter screens 15 are provided at both ends of the concrete specimen 12 .

[0053] In one embodiment of the present invention, two ends of the concrete specimen 12 are fixed by a filter screen 15 .

[0054] As an optional embodiment, the inner diameter of the copper tube is W1 = 12 mm, the inner diameters of the water inlet 13, the air inlet 14 and the water outlet 5 are all W2 = 6 mm, the length of the concrete specimen 12 is W3 = 20 mm, and the length of the copper tube is W4 = 30 mm.

[0055] As an optional embodiment, a magnetic stirrer 6 is further included, and the magnetic stirrer 6 is installed on the low-temperature reaction tank 4.

[0056] In one embodiment of the present invention, the mixed recycled aggregate and seawater are mixed and stirred by a magnetic stirrer 6 .

[0057] As an optional embodiment, the solid waste in the heating mold 10 is steel slag, and the porosity of the steel slag is 51%.

[0058] In one embodiment of the present invention, the multi-source solid waste is at least one of steel slag, recycled aggregate, shell and coral, preferably steel slag. According to the designed porosity of 51%, the steel slag is placed in a heated mold 10, and then a 300-mesh filter 15 is used to fix the two ends of the steel slag.

[0059] As an optional embodiment, a flow meter 3 is installed at the output end of the gas cylinder 1.

[0060] In one embodiment of the present invention, a flow meter 3 is provided to facilitate control of the gas delivery amount.

[0061] A method for synergistically treating solid waste concrete using seawater and carbon dioxide comprises the following steps:

[0062] The recycled aggregate is crushed into powder and mixed with seawater, and then added into the low-temperature reaction tank 4 for mixing and stirring;

[0063] Open the gas cylinder 1 and introduce carbon dioxide gas into the low-temperature reaction tank 4, and set the temperature in the low-temperature reaction tank 4 to 5°C;

[0064] The solid waste is placed in a heating mold 10 and the temperature is set to 80°C;

[0065] The mixed solution in the low-temperature reaction tank 4 is transported to the heating mold 10 to prepare a concrete specimen;

[0066] The concrete specimens were taken out for drying.

[0067] In one embodiment of the present invention, before the device is operated, the recycled aggregate is crushed into powder, 5 g of recycled aggregate powder is weighed, mixed with 1000 g of seawater, and then poured into the low-temperature reaction tank 4. When the device starts operating, the low-temperature reaction tank 4 is placed on the magnetic stirrer 6, the magnetic stirrer 6 is turned on, and the speed is set to 2000 r / min to fully mix the recycled aggregate powder and the seawater. Open the gas cylinder 1, turn on the flowmeter 3, control the carbon dioxide flow rate to 0.2 L / min, and introduce carbon dioxide into the mixed solution of seawater and recycled aggregate powder in the low-temperature reaction tank 4. Turn on the low-temperature controller 2 and set the temperature to 5°C. Put the steel slag into the heating mold 10 according to the designed initial porosity, and then use a 300-mesh filter to fix the two ends of the steel slag, and encapsulate the heating mold 10. Turn on the heating controller and set the temperature to 80°C. The multi-channel intermittent controller 9, water pump 7 and air pump 8 were connected in sequence, and the intermittent parameters of the multi-channel intermittent controller 9 were set as follows: the water pump was on for 3 hours, off for 0.5 hours, and the air pump was off for 3 hours, on for 0.5 hours. The water pump 7 controlled the solution flow rate to be 1 mL / min, and the air pump 8 controlled the gas flow rate to be 18 L / min. During the operation of the device, the pH value of the mixed solution in the low-temperature reaction tank 4 was adjusted using carbonic acid and sodium hydroxide, and the pH value was controlled to be 6-8. After the device was operated until the mixed solution in the low-temperature reaction tank 4 could no longer pass through the heating mold 10, the device was turned off. The concrete specimen was removed from the heating mold 10 and placed in an oven at 80°C. After drying for 24 hours, the concrete specimen was taken out and its compressive strength, porosity and phase composition were tested.

[0068] Comparative Example 1

[0069] The low-temperature reaction tank 4 does not contain seawater, but contains a mixed solution of recycled aggregate powder and deionized water, and the above method is used to prepare pressure-free all-solid waste concrete.

[0070] Comparative Example 2

[0071] The low-temperature reaction tank 4 and the low-temperature controller 2 are not provided. The steps for preparing pressure-free all-solid waste concrete using the above method are as follows:

[0072] Before operating the device, crush the recycled aggregate into powder. Weigh 5g of the recycled aggregate powder, mix it with 1000g of deionized water, and pour it into a beaker. Once the device is running, place the beaker on a magnetic stirrer 6 and turn it on at 2000 rpm to thoroughly mix the recycled aggregate powder and seawater.

[0073] Table 1

[0074] Group Compressive strength / MPa Quality growth rate / % Porosity / % Example 15.1 16.7 32.1％ Comparative Example 1 7.2 5.7 37.4％ Comparative Example 2 6.3 5.4 41.0％

[0075] Table 1 shows the compressive strength, mass growth rate, and porosity of the concrete specimens in the present application, Comparative Example 1, and Comparative Example 2. It can be found that the compressive strength of the present application is 15.1 MPa, which is an increase of 109.7% and 118.8% compared to Comparative Example 1 and Comparative Example 2, respectively. At the same time, the mass growth rate of the present application is much higher than that of Comparative Example 1 and Comparative Example 2. In addition, the porosity of the present application is also much lower than that of Comparative Example 1 and Comparative Example 2. This shows that the setting of a low-temperature carbonization environment and the presence of seawater can significantly improve the mechanical properties and density of all-solid waste concrete specimens.

[0076] Reference Figure 3 , the present application contains a large amount of aragonite and a small amount of calcite, while Comparative Example 1 contains a small amount of aragonite and a large amount of calcite, which is mainly because the magnesium ions in seawater help to regulate the conversion of calcium carbonate crystal forms into aragonite. It can also be found that there is no aragonite in Comparative Example 2, and the calcium carbonate crystal forms are all calcite. This is mainly because under normal temperature conditions, the calcium bicarbonate generated by the reaction of calcium carbonate with carbon dioxide and water is unstable and easily decomposed. This will cause the carbonized cementing fluid prepared in Comparative Example 2 to have an extremely low calcium bicarbonate content, and the main components of the solution are mainly water-soluble carbon dioxide and carbonic acid. It can be inferred that only the chemical reaction of steel slag with water-soluble carbon dioxide and carbonic acid occurs in the heated mold of Comparative Example 2, while in addition to the chemical reaction of steel slag with water-soluble carbon dioxide and carbonic acid, the heated molds of the present application and Comparative Example 2 also contain a mineralization reaction in which calcium bicarbonate is thermally decomposed to generate calcium carbonate. Therefore, the generation of aragonite is mainly the result of the chemical reaction of calcium bicarbonate to generate calcium carbonate, and aragonite helps to improve the compressive strength of all-solid waste concrete.

[0077] like Figure 4-Figure 6, the thermal decomposition peaks corresponding to the calcium carbonate in Comparative Examples 1 and 2 are all lagged behind that of the present application. This is because the corresponding crystalline and amorphous phase components of the calcium carbonate products in the present application, Comparative Example 1 and Comparative Example 2 are different. The decomposition temperature of amorphous calcium carbonate is 550-680°C, the decomposition temperature of aragonite is 680-720°C, and the decomposition temperature of calcite is 720-1000°C. Therefore, due to the high aragonite content in the present application, the corresponding peak decomposition temperature of the calcium carbonate product is lower than that in Comparative Example 1 and Comparative Example 2. According to thermogravimetric analysis, the carbon dioxide absorption rates of the present application, Comparative Example 1 and Comparative Example 2 are 7.4%, 9.7% and 10.6% respectively, but the porosity of the present application is the lowest, at 32.1%. This is mainly because most of the calcium element in the calcium carbonate product in the present application comes from the recycled aggregate powder in the low-temperature reaction tank, while most of the calcium element in the calcium carbonate products in Comparative Examples 1 and 2 comes from in-situ steel slag. This also further illustrates that high-strength all-solid waste pressure-free negative carbon concrete not only requires in-situ carbonization product deposition to cement aggregate particles, but also requires the directional deposition of ex-situ carbonization products.

[0078] Example 1:

[0079] The difference of this embodiment is that the flow meter 3 controls the flow rate of carbon dioxide to 0.4 L / min, and the temperature of the heating mold 10 is set to 60° C. The above method is used to prepare pressure-free all-solid waste concrete.

[0080] The properties of the all-solid waste pressure-free negative carbon concrete prepared in Example 1 are shown in Table 2. As can be seen from Table 2, the compressive strength and mass growth rate of Example 1 are lower than those of the above-mentioned examples of this application, and the porosity is higher than that of the above-mentioned examples of this application, but the carbon dioxide absorption rate is slightly higher than that of the above-mentioned examples of this application.

[0081] Table 2

[0082] Group Compressive strength / MPa Quality growth rate / % Porosity / % Carbon dioxide absorption rate / % Example 1 12.3 14.2 35.3 8.1

[0083] Example 2:

[0084] This embodiment differs from the first embodiment in that the multi-source solid waste in the low-temperature reaction tank 4 is shells, the temperature is set to 1°C, the temperature of the heating mold 10 is set to 70°C, and the internal steel slag has a designed porosity of 40%. The above method is used to prepare pressure-free, all-solid waste concrete.

[0085] The properties of the all-solid waste pressure-free negative carbon concrete prepared in Example 2 are shown in Table 3. As can be seen from Table 3, the compressive strength, mass growth rate, and carbon dioxide absorption rate of Example 2 are higher than those of the present embodiment and Example 1, and the porosity is lower than that of the present embodiment and Example 1.

[0086] Table 3

[0087] Group Compressive strength / MPa Quality growth rate / % Porosity / % Carbon dioxide absorption rate / % Example 2 16.5 17.8 31.6 8.6

[0088] Example 3:

[0089] This embodiment differs from the previous embodiment in that the multi-source solid waste in the low-temperature reaction tank 4 is coral skeleton, the temperature is set at 3°C, the flow meter 3 controls the carbon dioxide flow rate at 0.05 L / min, the water pump 7 controls the solution flow rate at 3 mL / min, and the air pump 8 controls the gas flow rate at 3 L / min. The above method is used to prepare pressure-free all-solid waste concrete.

[0090] The properties of the all-solid waste, pressure-free, negative carbon concrete produced in Example 3 are shown in Table 4. As can be seen from Table 4, the compressive strength and mass growth rate of Example 3 are lower than those of Example 1 and Example 2, but higher than those of Example 3. The corresponding concrete porosity is higher than that of Example 1 and Example 2, but lower than that of Example 1. However, the carbon dioxide absorption rate of Example 3 is higher than that of Example 1, Example 1, and Example 2.

[0091] Table 4

[0092] Group Compressive strength / MPa Quality growth rate / % Porosity / % Carbon dioxide absorption rate / % Example 3 13.6 15.2 34.3 10.2

[0093] Example 4

[0094] The difference between this embodiment and the embodiment is that the water pump 7 controls the solution flow rate to 2 mL / min, the air pump 8 controls the gas flow rate to 10 L / min, and the porosity of the steel slag inside the heating mold 10 is designed to be 60%. The above method is used to prepare pressure-free all-solid waste concrete.

[0095] The properties of the all-solid waste, pressure-free, negative carbon concrete produced in Example 4 are shown in Table 5. As can be seen from Table 5, the compressive strength and mass growth rate of Example 4 are lower than those of Example 4, Example 1, Example 2, and Example 3, while the porosity is higher than that of Example 4, Example 1, Example 2, and Example 3. Comparing Example 4, Example 1, Example 2, Example 3, and Example 4, the concrete performance of Example 2 is the best, followed by Example 4. However, in terms of carbon dioxide absorption rate, Example 4 has the highest, followed by Example 3.

[0096] Table 5

[0097] Group Compressive strength / MPa Quality growth rate / % Porosity / % Carbon dioxide absorption rate / % Example 4 10.4 12.7 36.9 10.6

[0098] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0099] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A device for treating solid waste concrete by synergistically using seawater and carbon dioxide, characterized in that: include: a low-temperature reaction tank (4), wherein solid waste and seawater are placed in the low-temperature reaction tank (4); A cooling system comprising a gas cylinder (1) and a low-temperature controller (2), wherein the gas cylinder (1) is in communication with the low-temperature reaction tank (4) for delivering carbon dioxide gas into the low-temperature reaction tank (4), and the low-temperature controller (2) is electrically connected to the low-temperature reaction tank (4); A heating system comprises a heating mold (10) and a heating controller (11), wherein solid waste is arranged in the heating mold (10), and the heating mold (10) is connected to a low-temperature reaction tank (4) through a control component, wherein the control component is used to transport the solution in the low-temperature reaction tank (4) and the outside air into the heating mold (10), and the heating controller (11) is electrically connected to the heating mold (10).

2. The device for collaboratively treating solid waste concrete using seawater and carbon dioxide according to claim 1, characterized in that: The control component comprises a water pump (7) and an air pump (8), the input end of the water pump (7) is connected to the low-temperature reaction tank (4), and the output ends of the water pump (7) and the air pump (8) are respectively connected to the heating mold (10).

3. The device for collaboratively treating solid waste concrete using seawater and carbon dioxide according to claim 2, characterized in that: It also includes a multi-channel intermittent controller (9), and the water pump (7) and the air pump (8) are electrically connected to the multi-channel intermittent controller (9) respectively.

4. The device for synergistically treating solid waste concrete with seawater and carbon dioxide according to claim 3, characterized in that: The heating mold (10) comprises a copper tube and two joints, wherein an electric heating wire is wound around the copper tube, and a water inlet (13) and an air inlet (14) are provided on the upper joint, wherein the water inlet (13) is connected to the output end of the water pump (7), and the air inlet (14) is connected to the output end of the air pump (8), and a water outlet (5) is provided on the lower joint.

5. The device for collaboratively treating solid waste concrete using seawater and carbon dioxide according to claim 4, characterized in that: The concrete test piece (12) is located in the copper tube, and filter screens (15) are provided at both ends of the concrete test piece (12).

6. The device for collaboratively treating solid waste concrete using seawater and carbon dioxide according to claim 5, characterized in that: The inner diameter of the copper tube is W1=12 mm, the inner diameters of the water inlet (13), the air inlet (14) and the water outlet (5) are all W2=6 mm, the length of the concrete specimen (12) is W3=20 mm, and the length of the copper tube is W4=30 mm.

7. The device for collaboratively treating solid waste concrete using seawater and carbon dioxide according to claim 1, characterized in that: It also includes a magnetic stirrer (6), which is installed on the low-temperature reaction tank (4).

8. The device for collaboratively treating solid waste concrete using seawater and carbon dioxide according to claim 1, characterized in that: The solid waste in the low-temperature reaction tank (4) and the heating mold (10) is at least one of steel slag, recycled aggregate, shells or corals.

9. The device for collaboratively treating solid waste concrete using seawater and carbon dioxide according to claim 1, characterized in that: A flow meter (3) is installed at the output end of the gas cylinder (1).

10. A method for co-processing solid waste concrete using seawater and carbon dioxide, applicable to the device for co-processing solid waste concrete using seawater and carbon dioxide according to claim 1, characterized in that: The following steps are involved: Open the gas cylinder and introduce carbon dioxide gas into the low-temperature reaction tank, and set the temperature in the low-temperature reaction tank to 1-5°C; Place the solid waste into a heated mold and set the temperature to 60-80°C; transporting the mixed solution in the low-temperature reaction tank to the heating mold to prepare a concrete specimen; The concrete specimens were taken out for drying.

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