Grounding resistance reduction module and use method thereof

Abstract

The present invention provides a grounding resistance reduction module and a method for using the same, and belongs to the technical field of safe grounding. The grounding resistance reduction module comprises the following raw materials in parts by weight: 40-50 parts of fly ash cement; 5-12 parts of gypsum; 3-8 parts of carbon nanotubes; 5-12 parts of conductive carbon black; 5-10 parts of sodium sulfate; 7-15 parts of calcium chloride; 5-10 parts of foaming agent; and 12-25 parts of water. The present invention uses fly ash cement as the main raw material, with gypsum, sodium sulfate, calcium chloride, and adds an appropriate amount of carbon nanotubes and conductive carbon black, and prepares a grounding resistance reduction prefabricated block by foaming with a foaming agent. The grounding resistance reduction prefabricated block has good resistance reduction and corrosion resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of safe grounding, and in particular relates to a grounding resistance reduction module and a use method thereof. Background Art

[0002] The grounding device is an important protection and defense facility that is indispensable in the fields of electricity, electrical appliances, computer systems, communication systems and other fields. In general, the grounding body materials in the grounding device are mostly made of steel materials, and a very small part is made of copper materials. The grounding body materials are buried in the soil and are very easy to react with the active particles in the soil, causing the grounding body materials to corrode. Under normal circumstances, the service life of the grounding body made of steel materials is 5-8 years, and the service life is 3-5 years under harsh corrosive environment conditions. Therefore, it is a preferred option to choose a corrosion-resistant, low-volume resistivity, and cost-effective material as the grounding body material. At present, the materials with good corrosion resistance used in the grounding device include metal copper materials, graphite materials (graphite modules and graphite ropes), and flexible metal-non-metal composite conductive materials. The corrosion problem of the grounding body material of the grounding device has always been a difficult problem that plagues the grounding device.

[0003] Document CN112079637A discloses a composite grounding module and a preparation method thereof, comprising a grounding module carrier and a metal electrode partially wrapped in the grounding module carrier, wherein the grounding module carrier is composed of 50% petroleum coke, 35% coal tar coke, and 15% graphite, calculated by mass percentage. The composite grounding module is prepared by batching, grinding, kneading, molding, roasting, calcining, graphitization treatment, and maintenance. The preparation process of the composite grounding module is complex and not energy-saving and environmentally friendly.

[0004] Document CN110661110A discloses a composite material grounding module and its manufacturing mold, wherein the module includes grounding modules greater than or equal to 2 connected in sequence by connecting wires; the grounding module includes a metal skeleton and a composite layer covering the metal skeleton; the two ends of the metal skeleton respectively penetrate the composite layer and are provided with connecting holes. The technical solution provided by the invention connects the grounding modules formed by the metal skeleton and the composite layer in sequence to form a grounding module, the hygroscopicity and adhesion of the composite layer are better than those of metal, and the density of adhesion with soil is also better than that of metal, thereby reducing the contact resistance between the grounding module and the soil and the grounding resistance of the grounding module; and the composite material can protect the metal, avoid the corrosion of the metal, increase the overall corrosion resistance of the grounding module, and greatly improve its service life.

[0005] The above-mentioned prior art provides different methods for implementing grounding resistance reduction. Meanwhile, in order to achieve a better grounding resistance reduction effect, technicians in this field are still constantly exploring and optimizing. Summary of the invention

[0006] In view of this, the technical problem to be solved by the present invention is to provide a grounding resistance reduction module with good resistance reduction and corrosion resistance in view of the deficiencies in the prior art.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0008] The grounding resistance reduction module comprises the following raw materials in parts by weight: 40-50 parts of fly ash cement; 5-12 parts of gypsum; 3-8 parts of carbon nanotubes; 5-12 parts of conductive carbon black; 5-10 parts of sodium sulfate; 7-15 parts of calcium chloride; 5-10 parts of foaming agent; and 12-25 parts of water.

[0009] Among them, fly ash cement is fly ash silicate cement, which is made by grinding silicate cement clinker and fly ash with appropriate amount of gypsum, code PF. Fly ash cement has a relatively dense structure, small internal specific surface area, small shrinkage and good crack resistance. In addition, similar to cement with general active admixtures, it has low hydration heat and strong corrosion resistance.

[0010] Further preferably, the grounding resistance reduction module comprises the following raw materials in parts by weight: 45 parts of fly ash cement; 8 parts of gypsum; 5 parts of carbon nanotubes; 8 parts of conductive carbon black; 7 parts of sodium sulfate; 10 parts of calcium chloride; 7 parts of foaming agent; and 20 parts of water.

[0011] Further preferably, the grounding resistance reduction module further includes a dispersant, and the dispersant is a dispersant SDS-720 or a DS-162 high-efficiency dispersant.

[0012] More preferably, the weight portion of the dispersant is 1-5 parts.

[0013] More preferably, the foaming agent is a composite foaming agent.

[0014] Further preferably, the grounding resistance reduction module is made of the following raw materials in parts by weight: 45 parts of fly ash cement; 8 parts of gypsum; 5 parts of carbon nanotubes; 8 parts of conductive carbon black; 7 parts of sodium sulfate; 10 parts of calcium chloride; 3 parts of dispersant; 7 parts of foaming agent; and 20 parts of water.

[0015] The preparation method of the grounding resistance reduction module comprises the following steps:

[0016] S1. Weigh the following raw materials in parts by weight: 40-50 parts of fly ash cement; 5-12 parts of gypsum; 3-8 parts of carbon nanotubes; 5-12 parts of conductive carbon black; 5-10 parts of sodium sulfate; 7-15 parts of calcium chloride; 1-5 parts of dispersant; 5-10 parts of foaming agent; and 12-25 parts of water.

[0017] S2, mixing fly ash cement, gypsum, carbon nanotubes, conductive carbon black, sodium sulfate, calcium chloride and a dispersant, adding water, and continuing to stir and mix to obtain a feed liquid;

[0018] S3: dissolving a foaming agent in water to form foam;

[0019] S4: The slurry is loaded into a mold, and the foam is introduced into the slurry for foaming to obtain a finished product.

[0020] It is further preferred that step S2 is:

[0021] S21: mixing carbon nanotubes, conductive carbon black and a dispersant, adding water, and ultrasonically treating to obtain a dispersion;

[0022] S22: Mix fly ash cement, gypsum, sodium sulfate and calcium chloride, add water and stir, then add the dispersion liquid, continue stirring to obtain a feed liquid.

[0023] More preferably, the mold may be in a rectangular shape, a cube shape or a column shape.

[0024] The method for using the grounding resistance reduction module includes the following steps:

[0025] Dig a trench near the grounding body, place the grounding resistance reduction module flat in the trench, connect it to the grounding body, and finally cover the trench with soil.

[0026] my country's line grounding grid generally uses metal grounding materials such as copper, stainless steel and flat steel. There is also a part of grounding materials such as stainless steel-clad steel and copper-clad steel, electroplated metal layer and galvanized steel. In addition to the problems of difficulty in construction and transportation and easy theft, the most important problem of metal grounding materials is the corrosion of grounding materials. Grounding modules usually use other colloids or conductive cement to wrap galvanized steel, flat steel and round steel in the grounding body to prepare relatively large polygonal, square and cylindrical grounding modules to play a good role in reducing resistance and preventing corrosion. At present, there is application experience in some transmission lines. According to the actual engineering excavation of grounding modules, some internal metal materials are still corroded. On the one hand, it is because the geology of the grounding module is relatively soft, and air and moisture can penetrate into it. On the other hand, there is electrochemical corrosion on the top of the metal material. From the current use of non-metallic grounding materials, the combination of general metal grounding materials and auxiliary grounding materials of metal grounding grids can effectively achieve the purpose of corrosion prevention and resistance reduction. The current grounding projects for power transmission line towers are still mainly based on galvanized steel and steel (copper-clad steel is required in harsh geological conditions) due to the cost of grounding materials.

[0027] Graphite grounding module is one of the most widely used grounding module technologies. Graphite is a good conductor. The graphite grounding module is in close contact with the soil, expanding the surface area of ​​the scattered flow. Graphite penetrates into the pores of the surrounding soil, reducing the contact resistance with the soil, forming a low-resistance area with a gentle resistivity change around it, which significantly reduces the grounding resistance of the entire ground grid.

[0028] However, the general graphite grounding module has low product strength, and there are problems such as easy damage during transportation and handling, easy moisture absorption during storage, which reduces performance, and the resistance reduction effect is quickly lost after burial, and the service life is short. Therefore, it is not suitable for long-distance transportation with poor road conditions. It is necessary to pay attention to bumping during transportation to prevent product damage or even breakage; special attention should be paid to dryness and moisture-proof during storage. Do not scatter it on the ground. It is best to seal it and avoid contact with air to avoid volatilization and other problems; if it is not stored well, once the product comes into contact with wet ingredients or moisture and other unfavorable factors, it will react with it. In addition to volatilization, other unfavorable situations will occur, resulting in the loss of product function. This phenomenon is caused by the construction unit needing to delay the construction period due to many external factors, resulting in the problem of too long storage time. These problems are the main factors that cause the general graphite grounding module to be easily damaged and have a relatively short service life. In addition, the burial site of the general graphite grounding module is required to be away from heat sources and try to avoid places with strong corrosive substances to prevent the grounding module from being corroded, thereby reducing the service life.

[0029] In the prior art, CN112079637A provides a composite grounding module, including a grounding module carrier and a metal electrode partially wrapped in the grounding module carrier, wherein the grounding module carrier is composed of 50% petroleum coke, 35% coal tar coke, and 15% graphite, calculated by mass percentage. Although the grounding module has high strength and good corrosion resistance, the energy consumption of the manufacturing process is also quite high, which has limitations on promotion.

[0030] For another example, CN112332123A provides a method for reducing resistance by grounding layered soil in a hydropower station, which includes the following steps: setting a grounding module in the soil, setting a permeation area and a water storage area inside the grounding module; replacing the second soil layer with the same low resistivity soil as the first soil layer; grouting the third soil layer with a resistance reducing agent mixed with clay, pressing the slurry-like resistance reducing agent into the gaps between the rocks in the third soil layer, and communicating the soil and the rock internally through the diffusion of ions in the mixture to form a three-dimensional grounding network that diffuses along the gaps. This technology uses high-concentration resistance reducing agent grouting to penetrate deep gravel and weathered metamorphic rock accumulation areas, but the use process is cumbersome.

[0031] In summary, both the graphite grounding module and the resistance reducing agent technology have certain shortcomings in their preparation or use, and there is still room for improvement or optimization.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] The invention uses fly ash cement as the main raw material, mixes with gypsum, sodium sulfate, calcium chloride, adds appropriate amount of carbon nanotubes and conductive carbon black, and prepares the grounding resistance reduction prefabricated block through foaming with a foaming agent. The grounding resistance reduction prefabricated block has good resistance reduction and corrosion resistance.

[0034] In the present invention, fly ash cement has high resistance to fresh water and sulfate corrosion, and has good workability and can be easily mixed with different raw materials, which provides a good foundation for the uniform dispersion of carbon nanotubes and conductive carbon black; and the corrosion resistance of the main material also makes the grounding resistance reduction module have good corrosion resistance, and can maintain good properties in the soil.

[0035] In addition, the present invention also adds gypsum, sodium sulfate and calcium chloride to improve the reaction performance of the main material and the foaming agent, so that the foaming effect is better, and the obtained grounding resistance reduction module has more uniform performance and better durability. The present invention adds an appropriate amount of carbon nanotubes and conductive carbon black to the main material to improve the conductivity, reduce the contact resistance between the grounding body and the soil, and achieve the resistance reduction effect.

[0036] The grounding resistance reduction module of the present invention is connected to the grounding body when in use and placed in the soil. It can effectively solve the problem that the metal grounding body has poor affinity in acidic or alkaline soil and is prone to rust on the surface of the metal body, causing the grounding resistance to change. It increases the dispersion area of ​​the grounding body itself, reduces the contact resistance between the grounding body and the soil, and can alleviate the corrosion problem of the grounding body.

[0037] The grounding resistance reduction module of the present invention has the following characteristics: it has been confirmed by experiments that its corrosion resistance is relatively high, and it can be used in conjunction with a grounding body to reduce the life cycle cost of the grounding device; the mechanical properties are stable, the grounding resistance reduction module has good compressive resistance, can meet the needs of actual engineering grounding construction, and is easy to transport; the materials used are relatively low in price and do not contain precious materials, which can prevent human damage and theft. DETAILED DESCRIPTION

[0038] In order to better understand the present invention, the content of the present invention is further clearly set forth in conjunction with the embodiments below, but the protection content of the present invention is not limited to the following embodiments. In the following description, a large number of specific details are provided in order to provide a more thorough understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without one or more of these details.

[0039] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0040] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0041] Unless otherwise specified, all raw materials are from commercially available products and do not contain other unspecified components except inevitable impurities unless otherwise specified.

[0042] Example 1

[0043] The grounding resistance reduction module is made of the following raw materials in parts by weight: 45 parts of fly ash cement; 8 parts of gypsum; 5 parts of carbon nanotubes; 8 parts of conductive carbon black; 7 parts of sodium sulfate; 10 parts of calcium chloride; 3 parts of dispersant; 7 parts of foaming agent; and 20 parts of water.

[0044] Wherein, the dispersant is dispersant SDS-720.

[0045] The foaming agent is composite plant protein cement foaming agent FP-50.

[0046] The preparation method of the grounding resistance reduction module comprises the following steps: weighing various raw materials; mixing carbon nanotubes, conductive carbon black and a dispersant, adding water, and ultrasonically treating to obtain a dispersion liquid; mixing fly ash cement, gypsum, sodium sulfate and calcium chloride, adding water and stirring, then adding the dispersion liquid, and continuing to stir to obtain a feed liquid; dissolving a foaming agent in water to prepare foam; loading the feed liquid into a mold, and introducing the foam into the feed liquid for foaming to obtain a finished product.

[0047] The method for using the grounding resistance reduction module comprises the following steps: digging a trench near a grounding body, placing the grounding resistance reduction module flatly in the trench, connecting it to the grounding body, and finally covering the trench with soil.

[0048] Example 2

[0049] The grounding resistance reduction module is made of the following raw materials in parts by weight: 40 parts of fly ash cement; 5 parts of gypsum; 3 parts of carbon nanotubes; 5 parts of conductive carbon black; 5 parts of sodium sulfate; 7 parts of calcium chloride; 1 part of dispersant; 5 parts of foaming agent; and 12 parts of water.

[0050] Among them, the dispersant is DS-162 high-efficiency dispersant.

[0051] The foaming agent is composite plant protein cement foaming agent FP-50.

[0052] The preparation method of the grounding resistance reduction module comprises the following steps: weighing various raw materials; mixing fly ash cement, gypsum, carbon nanotubes, conductive carbon black, sodium sulfate, calcium chloride and a dispersant, adding water, and continuing to stir and mix to obtain a slurry; dissolving a foaming agent in water to prepare foam; loading the slurry into a mold, introducing the foam into the slurry for foaming, and obtaining a finished product.

[0053] Example 3

[0054] The grounding resistance reduction module is made of the following raw materials in parts by weight: 50 parts of fly ash cement; 12 parts of gypsum; 8 parts of carbon nanotubes; 12 parts of conductive carbon black; 10 parts of sodium sulfate; 15 parts of calcium chloride; 5 parts of dispersant; 10 parts of foaming agent; and 25 parts of water.

[0055] Wherein, the dispersant is dispersant SDS-720.

[0056] The foaming agent is a composite foaming agent ADC.

[0057] The preparation method of the grounding resistance reduction module refers to Example 1.

[0058] Example 4

[0059] The grounding resistance reduction module is made of the following raw materials in parts by weight: 42 parts of fly ash cement; 6 parts of gypsum; 4 parts of carbon nanotubes; 7 parts of conductive carbon black; 6 parts of sodium sulfate; 9 parts of calcium chloride; 2 parts of dispersant; 6 parts of foaming agent; and 15 parts of water.

[0060] Among them, the dispersant is DS-162 high-efficiency dispersant.

[0061] The foaming agent is a composite foaming agent ADC.

[0062] The preparation method of the grounding resistance reduction module refers to Example 1.

[0063] Example 5

[0064] The grounding resistance reduction module is made of the following raw materials in parts by weight: 48 parts of fly ash cement; 10 parts of gypsum; 7 parts of carbon nanotubes; 10 parts of conductive carbon black; 8 parts of sodium sulfate; 12 parts of calcium chloride; 4 parts of dispersant; 8 parts of foaming agent; and 23 parts of water.

[0065] Wherein, the dispersant is dispersant SDS-720.

[0066] The foaming agent is composite plant protein cement foaming agent FP-50.

[0067] The preparation method of the grounding resistance reduction module refers to Example 1.

[0068] Example 6

[0069] The grounding resistance reduction module is made of the following raw materials in parts by weight: 40-50 parts of fly ash cement; 9 parts of gypsum; 6 parts of carbon nanotubes; 9 parts of conductive carbon black; 7 parts of sodium sulfate; 9 parts of calcium chloride; 3 parts of dispersant; 8 parts of foaming agent; and 18 parts of water.

[0070] Wherein, the dispersant is dispersant SDS-720.

[0071] The foaming agent is composite plant protein cement foaming agent FP-50.

[0072] The preparation method of the grounding resistance reduction module refers to Example 1.

[0073] Comparative Example 1

[0074] The grounding resistance reduction module is made of the following raw materials in parts by weight: 30 parts of fly ash cement; 2 parts of gypsum; 5 parts of carbon nanotubes; 8 parts of conductive carbon black; 5 parts of sodium sulfate; 3 parts of calcium chloride; 3 parts of dispersant; 7 parts of foaming agent; 20 parts of water. Among them, the dispersant is dispersant SDS-720. The foaming agent is composite plant protein cement foaming agent FP-50.

[0075] The preparation method of the grounding resistance reduction module refers to Example 1.

[0076] Comparative Example 2

[0077] The grounding resistance reduction module is made of the following raw materials in parts by weight: 45 parts of fly ash cement; 8 parts of gypsum; 5 parts of carbon nanotubes; 8 parts of conductive carbon black; 7 parts of sodium sulfate; 10 parts of calcium chloride; 7 parts of foaming agent; and 20 parts of water. Among them, the dispersant is dispersant SDS-720. The foaming agent is composite plant protein cement foaming agent FP-50.

[0078] The preparation method of the grounding resistance reduction module refers to Example 2.

[0079] Comparative Example 3

[0080] The grounding resistance reduction module is made of the following raw materials in parts by weight: 45 parts of fly ash cement; 8 parts of gypsum; 8 parts of conductive carbon black; 7 parts of sodium sulfate; 10 parts of calcium chloride; 3 parts of dispersant; 7 parts of foaming agent; and 20 parts of water.

[0081] The dispersant is SDS-720 and the foaming agent is composite plant protein cement foaming agent FP-50.

[0082] The preparation method of the grounding resistance reduction module refers to Example 1.

[0083] Next, the content of the evaluation test will be described. The evaluation test was carried out on the following four evaluation items.

[0084] 1. According to the standards JG / T266-2011 and GB / T50081-2019, the 28d compressive strength of the test block is measured. The test block adopts a standard cubic specimen with a side length of 150mm, and is formed with a test mold of corresponding size. It is placed in a room with a temperature of 20±5℃ and a relative humidity of 50±5% for 24h. After demolding, it is immediately placed in a standard curing room with a temperature of 20±2℃ and a relative humidity of 95% for 28d.

[0085] 2. Salt spray resistance: After drying the three test blocks, use a knife to scratch them. The scratch distance from each edge of the test block or between the scratches is 25mm. The scratches should be straight lines. Then put the test blocks into a salt spray box at 35±2℃. Take them out after 420 hours and rinse them with clean warm water to remove the test solution residue on the surface of the test blocks. Then wipe the test blocks dry immediately and check the damage on the surface of the test blocks. If no bubbles are found and the rust on the scratches is not seriously spread, it is considered qualified.

[0086] 3. Resistivity, unit: Ω.m: Directly measured using a resistivity meter.

[0087] 4. Corrosion rate, unit: mm / a: GB10124-88 metal material laboratory uniform corrosion full immersion test method: Wire cutting was used to prepare 3 parallel samples, the sample height was 4mm and the diameter was Φ12mm. After grinding and polishing, ultrasonic cleaning was used and the weights were respectively M using an analytical balance. 0 The parallel samples were placed in a 3.5wt% NaCl solution at a constant temperature of 25°C for 720 h. After corrosion, the samples were rinsed with clean water and then CrO 3 , H 3 PO 4 Mix the solution with pure water and keep it warm at 80℃ for 5 minutes to remove the corrosion products on the sample surface. Rinse the cleaned sample with ultrapure water, blow dry it, and weigh the weight M after corrosion with an analytical balance. The calculation formula of corrosion rate is:

[0088] R corrosionrate =8.76×10 7 ×(MM 0 ) / (S×T×D),

[0089] R corrosionrate -Corrosion rate, mm / a; M 0 - Sample mass before the test, g; M- Test mass after the test, g; S- Total area of ​​the sample, cm 2 ; T-test time, h; D-material density, kg / m 3 .

[0090] The measurement results of the above examples 1-6 and comparative examples 1-3 are shown in the following table:

[0091]

[0092] It can be seen from the above data that the compressive strength of the grounding resistance reduction module of the present invention is above 4.5MPa, and it has good mechanical properties; it has good salt spray resistance; the electrical conductivity is below 1.3Ω.m; and the corrosion rate is low. In Comparative Example 1, the amount of fly ash cement, gypsum, sodium sulfate and calcium chloride is adjusted, and the compressive strength of the prepared grounding resistance reduction module is significantly reduced, and the salt spray resistance is poor. In Comparative Example 2, the dispersant is omitted, and the electrical conductivity and corrosion rate of the grounding resistance reduction material have obvious changes, which may be related to the dispersion uniformity of the carbon nanotubes and conductive carbon black therein. In Comparative Example 3, carbon nanotubes are omitted, and its electrical conductivity is significantly increased, and the corrosion rate is increased, which is not conducive to resistance reduction and corrosion protection. In summary, it can be seen that the grounding resistance reduction module of the present invention has good resistance reduction performance and corrosion resistance.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in the field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. Grounding resistance reduction module, characterized by: The preparation method comprises the following steps: S1. Weigh the following raw materials in parts by weight: 40-50 parts of fly ash cement, 5-12 parts of gypsum, 3-8 parts of carbon nanotubes, 5-12 parts of conductive carbon black, 5-10 parts of sodium sulfate, 7-15 parts of calcium chloride, 1-5 parts of dispersant, 5-10 parts of foaming agent, and 12-25 parts of water. The dispersant is SDS-720 or DS-162 high-efficiency dispersant, and the foaming agent is a composite foaming agent. S2, mixing fly ash cement, gypsum, carbon nanotubes, conductive carbon black, sodium sulfate, calcium chloride and a dispersant, adding water, and continuing to stir and mix to obtain a feed liquid; S3: dissolving a foaming agent in water to form foam; S4: The slurry is loaded into a mold, and the foam is introduced into the slurry for foaming to obtain a finished product.

2. The grounding resistance reduction module according to claim 1, characterized in that: The invention is prepared from the following raw materials in parts by weight: 45 parts of fly ash cement, 8 parts of gypsum, 5 parts of carbon nanotubes, 8 parts of conductive carbon black, 7 parts of sodium sulfate, 10 parts of calcium chloride, 3 parts of dispersant, 7 parts of foaming agent and 20 parts of water.

3. The grounding resistance reduction module according to claim 2, characterized in that: The step S2 is: S21: mixing carbon nanotubes, conductive carbon black and a dispersant, adding water, and ultrasonically treating to obtain a dispersion; S22: Mix fly ash cement, gypsum, sodium sulfate and calcium chloride, add water and stir, then add the dispersion liquid, continue stirring to obtain a feed liquid.

4. The grounding resistance reduction module according to claim 3, characterized in that: The mold is in the shape of a cuboid, a cube or a column.

5. The method of using the grounding resistance reduction module is characterized by: The following steps are involved: A trench is excavated near the grounding body, the grounding resistance reduction module according to any one of claims 1 to 4 is placed flat in the trench and connected to the grounding body, and finally the trench is covered with soil.

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