Photovoltaic-based reinforced concrete structure cathode protection equipment and method

Abstract

The invention relates to the field of cathode protection, and discloses a photovoltaic-based reinforced concrete structure cathode protection device and method.The photovoltaic-based reinforced concrete structure cathode protection device is composed of a cathode protection module, an intelligent monitoring module and a current control module; 2, preparing a photovoltaic-based power supply unit; 3, determining the number of power supply units according to the cathode protection design current density of the reinforced concrete structure; and 4, cleaning and dedusting the surface of the concrete structure, spraying a conductive coating, and installing the required number of power supply units on the surface of the concrete. Photovoltaic power generation is adopted to provide cathode protection current for the reinforcing steel bar, the cement-based super capacitor is introduced, and meanwhile, the positive electrode of the super capacitor is used as an auxiliary positive electrode, so that the problems that traditional impressed current cathode protection of a reinforced concrete structure is tedious in maintenance and not economical and environment-friendly are solved; the device has the characteristics of sustainable power supply, adjustable current and monitorable protection effect.

Description

Technical Field

[0001] The present invention relates to the field of cathodic protection, and in particular to a photovoltaic-based cathodic protection device and method for reinforced concrete structures. Background Art

[0002] Reinforced concrete structures are widely used in buildings, bridges, tunnels, and other projects. Their excellent mechanical properties and durability make them a staple material in modern engineering construction. However, over long-term use, particularly in harsh environments such as high salinity and humidity, reinforced concrete structures are susceptible to corrosion, leading to cracking and spalling of the concrete, seriously impacting the safety and service life of the structure. To effectively prevent steel corrosion and extend the service life of structures, cathodic protection technology has emerged.

[0003] Traditional impressed current cathodic protection (ICCP) involves embedding anodes in concrete structures and applying an impressed current to create a negative potential on the surface of the steel bars, thereby inhibiting the steel's oxidation reaction and achieving corrosion protection. This method has been widely used in engineering projects, especially in corrosion-prone structures such as bridges and docks. However, practical applications of this traditional method present several challenges: First, the ICCP system requires a stable power supply, and traditional power supply equipment is bulky, energy-intensive, and requires regular maintenance. Second, the system's installation and commissioning are complex, requiring a long construction cycle and increasing project costs. Finally, traditional systems have poor environmental adaptability, making it difficult to meet the needs of different regions and environmental conditions.

[0004] With the development of renewable energy technologies, photovoltaic power generation, as a green and clean energy source, has been increasingly applied in various fields. Combining photovoltaic power generation with cathodic protection technology for reinforced concrete structures, using solar energy to power the cathodic protection system, not only solves the problem of traditional power supply but also reduces energy consumption, minimizes environmental impact, and improves system stability and adaptability. Therefore, the development of a photovoltaic-based cathodic protection method and equipment for reinforced concrete structures has important practical significance and application value. Summary of the Invention

[0005] This paper addresses the challenges of traditional impressed current cathodic protection methods in engineering applications, such as unstable power supply, high energy consumption, and complex construction. By utilizing photovoltaic power generation to power the cathodic protection system and combining it with cement-based supercapacitors, this method creates a green, environmentally friendly, economical, easy-to-maintain, and current-adjustable cathodic protection system.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a photovoltaic-based cathodic protection equipment for reinforced concrete structures, comprising a power supply unit, wherein the power supply unit is composed of a thin-film photovoltaic sheet and a cement-based supercapacitor, wherein the thin-film photovoltaic sheet is fixed on the upper side of the cement-based supercapacitor, and the cement-based supercapacitor comprises a positive electrode, an ion permeable membrane, an interlayer material, a titanium mesh anode and a negative electrode.

[0007] Preferably, an ion permeable membrane is fixed between the bottom of the positive electrode and the top of the separator material, and between the bottom of the separator material and the top of the negative electrode, and a titanium mesh anode is fixed in the negative electrode.

[0008] Preferably, the thin-film photovoltaic cell is an amorphous silicon thin-film solar cell, the positive electrode is composed of porous graphene, and the thickness of the positive electrode is not less than 2 mm, the ion permeability membrane is selected from one of a porous inorganic membrane, a polymer-based membrane and a composite membrane, and the interlayer material is composed of cement, water, and alkaline electrolyte in a ratio of: 1::, wherein the alkaline electrolyte is KOH or NaCl.

[0009] Preferably, the titanium mesh anode is a titanium mesh coated with a precious metal oxide, the negative electrode is composed of porous graphene, and the thickness of the negative electrode is not less than 5 mm.

[0010] A photovoltaic-based cathodic protection method for reinforced concrete structures comprises the following steps: S1. Prepare a photovoltaic-based power supply unit: The power supply unit is composed of a thin-film photovoltaic sheet and a cement-based supercapacitor, with the thin-film photovoltaic sheet located on the upper portion and the cement-based supercapacitor located on the lower portion, and the two are connected to form a whole with an insulating adhesive; S2. Determine the number of power supply units based on the design current density of cathodic protection for reinforced concrete structures; S3. Clean the surface of the reinforced concrete structure to be protected, spray the conductive coating, and install the power supply unit according to the design requirements to ensure a close fit with the structure surface; S4. Connect the negative electrode of the cement-based supercapacitor inside the power supply unit to the steel bars of the structure to be protected. The positive electrode of the cement-based supercapacitor acts as an auxiliary anode through the titanium mesh anode to form a closed protection circuit with the steel bars. S5. Start the power supply unit. The thin-film photovoltaic sheet absorbs solar energy and converts it into electrical energy, which is stored in the cement-based supercapacitor. At the same time, a stable current is released to the steel bars for cathodic protection. S6. Use the intelligent monitoring module to collect current data and calculate current density; S7. Determine whether the current density meets the design requirements. If so, repeat S6-S7. If not, pass the adjustment instruction to the current control module to automatically adjust the protection current to meet the requirements.

[0011] Preferably, the conductive coating includes one of a metal-based conductive coating, a carbon-based conductive coating, a carbon fiber-reinforced conductive coating, and a polymer-based conductive coating.

[0012] Preferably, the specific steps for determining the number of power supply units are as follows: S1. First, calculate the total design protection current based on the protection area and the design current density; S2. Determine the number of power supply units based on the actual output current of a single power supply unit under local sunshine conditions; S3. Round the calculated number of power supply units to obtain the number of power supply units.

[0013] Preferably, the intelligent monitoring module includes a current sensor, a data processing unit and a wireless communication unit. The current sensor is buried in concrete, and the data processing unit and the wireless communication unit are placed on the surface of the concrete structure. The three are connected in a plastic protective shell through wires.

[0014] Preferably, the current control module uses a current controller to regulate the current, and the current controller is connected to the power supply unit and placed in a plastic protective shell.

[0015] Preferably, in S7, if the collected current density is greater than the maximum value of the design range, the current density value is reduced by 1 mA·m-2 each time; if the collected current density is less than the minimum value of the design range, the current density value is increased by 1 mA·m-2 each time.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention provides a photovoltaic-based cathodic protection equipment and method for reinforced concrete structures. The equipment integrates solar power generation, energy storage and cathodic protection functions. Since it does not require traditional external current facilities, it greatly reduces energy consumption and the subsequent operation and maintenance costs of cathodic protection.

[0017] 2. The photovoltaic-based cathodic protection equipment and method for reinforced concrete structures proposed in the present invention stores the electrical energy generated by photovoltaics in cement-based supercapacitors, and innovatively incorporates current control technology, so that reinforced concrete structures in rainy days or environments that are not exposed to sunlight for a long time can also obtain sufficient protection current, solving the problem that traditional photovoltaic-based external current technology cannot effectively provide sufficient protection current in rainy weather.

[0018] 3. The photovoltaic-based cathodic protection equipment and method for reinforced concrete structures proposed in the present invention innovatively integrates the auxiliary anode required by traditional impressed current protection technology into the negative electrode of the cement-based supercapacitor, and regards the composite anode structure of the two as the cathodic protection auxiliary anode, making the entire cathodic protection system simpler and easier to install. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic structural diagram of the power supply unit of the present invention; Figure 2 This is a schematic flow chart of the photovoltaic-based cathodic protection method for reinforced concrete structures of the present invention.

[0020] In the figure: 1. Thin-film photovoltaic cell; 2. Cement-based supercapacitor; 201. Positive electrode; 202. Ion permeable membrane; 203. Interlayer material; 204. Titanium mesh anode; 205. Negative electrode. DETAILED DESCRIPTION

[0021] 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.

[0022] See also Figure 1-Figure 2 This embodiment provides a photovoltaic-based cathodic protection device and method for reinforced concrete structures. A reinforced concrete bridge in a marine environment requires cathodic protection of the steel bars. The area A of the reinforced concrete to be protected is 200m², and the design current density range is 12 to 18mA·m-2. The target design current density is I=15mA·m-2.

[0023] (1) Prepare a photovoltaic-based power supply unit. The basic parameters of the power supply unit are as follows: 1. Thin-film photovoltaic cell 1 uses amorphous silicon thin-film solar cells with a single-chip open-circuit voltage of 2V and a maximum output current of Ip=500mA (at a light intensity of 1000W / m²); 2. The overall dimensions of the cement-based supercapacitor 2 are 100 mm × 100 mm × 20 mm. The positive electrode 201 is porous graphene with a thickness of 2 mm. The ion permeable membrane 202 is a composite polymer-based diaphragm. The interlayer material 203 has a cement: water: KOH ratio of 1:0.5:0.25. The negative electrode 205 is porous graphene with a thickness of 5 mm. The titanium mesh anode 204 is an MMO titanium mesh coated with a carbon-based conductive coating. The thin-film photovoltaic sheet 1 is placed on the upper part of the power supply unit, and the cement-based supercapacitor 2 is placed on the lower part, and the two are sealed into a whole with an adhesive.

[0024] (2) Determine the number of power supply units based on the design current density of cathodic protection for reinforced concrete structures. The specific calculation steps are as follows: 1. Total design protection current At = A × I = 200m² × 15mA·m-2 = 3000mA.

[0025] 2. The output current Ig of the power supply unit is set to 50mA. The total number of power supply units required for the entire protection area of the bridge is N=At / Ig=60.

[0026] (3) Clean the surface of the reinforced concrete structure to be protected, spray the conductive coating, and install the power supply unit according to the design requirements to ensure that it fits tightly with the surface of the structure; (4) Connect the negative electrode 205 of the cement-based supercapacitor 2 inside each power supply unit to the surface of the steel bar through a copper wire to form a closed protection circuit; (5) The current controller is buried 10 cm below the concrete cover layer. The data processing unit and wireless communication module are installed in a waterproof plastic shell, and the shell is fixed to the side wall of the bridge; (6) Start the power supply unit, the thin-film photovoltaic sheet 1 absorbs solar energy and converts it into electrical energy and stores it in the cement-based supercapacitor 2, while releasing a stable current to the steel bar for cathodic protection; (7) The initial total current monitored was 3800 mA, and the calculated current density was 19 mA·m-2. At this time, the current density exceeded the design requirement of 12 to 18 mA·m-2. Therefore, the adjustment instruction was passed to the current control module, which reduced the total current of the power supply unit by 1 mA·m-2. The current density value collected again was 18 mA·m-2, which met the design requirements.

[0027] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A photovoltaic-based cathodic protection device for reinforced concrete structures, comprising a power supply unit, characterized in that: The power supply unit is composed of a thin film photovoltaic sheet (1) and a cement-based supercapacitor (2), wherein the thin film photovoltaic sheet (1) is fixed on the upper side of the cement-based supercapacitor (2), and the cement-based supercapacitor (2) comprises a positive electrode (201), an ion permeable membrane (202), an interlayer material (203), a titanium mesh anode (204), and a negative electrode (205).

2. The photovoltaic-based cathodic protection equipment for reinforced concrete structures according to claim 1, characterized in that: An ion permeable membrane (202) is fixed between the bottom of the positive electrode (201) and the top of the separator material (203), and between the bottom of the separator material (203) and the top of the negative electrode (205), and a titanium mesh anode (204) is fixed inside the negative electrode (205).

3. The photovoltaic-based cathodic protection equipment for reinforced concrete structures according to claim 1, characterized in that: The thin-film photovoltaic sheet (1) is an amorphous silicon thin-film solar cell, the positive electrode (201) is composed of porous graphene, and the thickness of the positive electrode (201) is not less than 2 mm, the ion permeation membrane is selected from one of a porous inorganic diaphragm, a polymer-based diaphragm and a composite diaphragm, and the barrier material (203) is composed of cement, water and alkaline electrolyte in a ratio of 1: (0.4-0.6): (0.2-0.3), wherein the alkaline electrolyte is KOH or NaCl.

4. The photovoltaic-based cathodic protection equipment for reinforced concrete structures according to claim 1, characterized in that: The titanium mesh anode (204) is a titanium mesh coated with a precious metal oxide, the negative electrode (205) is composed of porous graphene, and the thickness of the negative electrode (205) is not less than 5 mm.

5. A photovoltaic-based cathodic protection method for reinforced concrete structures, applied to a photovoltaic-based cathodic protection device for reinforced concrete structures according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Prepare a photovoltaic-based power supply unit: the power supply unit is composed of a thin film photovoltaic sheet (1) and a cement-based supercapacitor (2), wherein the thin film photovoltaic sheet (1) is located at the upper part and the cement-based supercapacitor (2) is located at the lower part, and the two are connected into a whole with an insulating adhesive; S2. Determine the number of power supply units based on the design current density of cathodic protection for reinforced concrete structures; S3. Clean the surface of the reinforced concrete structure to be protected, spray the conductive coating, and install the power supply unit according to the design requirements to ensure a close fit with the structure surface; S4, connecting the negative electrode (205) of the cement-based supercapacitor (2) inside the power supply unit to the steel bars of the structure to be protected, and the positive electrode (201) of the cement-based supercapacitor (2) acts as an auxiliary anode through the titanium mesh anode to form a closed protection circuit with the steel bars; S5, starting the power supply unit, the thin film photovoltaic sheet (1) absorbs solar energy and converts it into electrical energy and stores it in the cement-based supercapacitor (2), while releasing a stable current to the steel bar for cathodic protection; S6. Use the intelligent monitoring module to collect current data and calculate current density; S7. Determine whether the current density meets the design requirements. If so, repeat S6-S7. If not, pass the adjustment instruction to the current control module to automatically adjust the protection current to meet the requirements.

6. The photovoltaic-based cathodic protection method for reinforced concrete structures according to claim 5, characterized in that: The conductive coating includes one of a metal-based conductive coating, a carbon-based conductive coating, a carbon fiber-reinforced conductive coating, and a polymer-based conductive coating.

7. The photovoltaic-based cathodic protection method for reinforced concrete structures according to claim 5, characterized in that: The specific steps for determining the number of power supply units are as follows: S1. First, calculate the total design protection current based on the protection area and the design current density; S2. Determine the number of power supply units based on the actual output current of a single power supply unit under local sunshine conditions; S3. Round the calculated number of power supply units to obtain the number of power supply units.

8. The photovoltaic-based cathodic protection method for reinforced concrete structures according to claim 5, characterized in that: The intelligent monitoring module includes a current sensor, a data processing unit and a wireless communication unit. The current sensor is buried in concrete, and the data processing unit and the wireless communication unit are placed on the surface of the concrete structure. The three are connected in a plastic protective shell through wires.

9. The photovoltaic-based cathodic protection method for reinforced concrete structures according to claim 1, characterized in that: The current control module uses a current controller to adjust the current. The current controller is connected to the power supply unit and placed in a plastic protective shell.

10. The photovoltaic-based cathodic protection method for reinforced concrete structures according to claim 1, characterized in that: In S7, if the collected current density is greater than the maximum value of the design range, the current density value is reduced by 1 mA·m-2 each time; if the collected current density is less than the minimum value of the design range, the current density value is increased by 1 mA·m-2 each time.

Images