Water-absorbing moisturizing type long-acting resistance-reducing grounding module and industrial production method thereof

Abstract

The invention discloses a water-absorbing and moisture-preserving type long-acting resistance-reducing grounding module and an industrial production method thereof. The water-absorbing and moisture-preserving type long-acting resistance-reducing grounding module comprises a grounding module body, a graphite-based flexible grounding belt and a water-absorbing pipe. The grounding module body is obtained by mixing graphite chippings, bentonite and water glass and then performing compression molding. And one end of the graphite-based flexible grounding strip is arranged in the grounding module body. One end of the water suction pipe is arranged in the grounding module body, and a plurality of water inlet micropores are distributed in a pipe body of the water suction pipe. According to the invention, a'graphite conductive network-water glass ion channel-bentonite water storage unit 'ternary synergistic system is constructed, and the water absorption pipe absorbs water and stores the water into the module, so that the module can still keep stable grounding resistance in a drought or freeze thawing environment, and meanwhile, flexible graphite production waste is adopted as a main raw material, so that the cost is reduced, and the production efficiency is improved. Through surface activation, particle size grading and interface optimization, 100% solid waste resource utilization is realized.

Description

Technical Field

[0001] This invention relates to the field of power grounding materials technology, specifically to a water-absorbing and moisture-retaining long-lasting resistance-reducing grounding module and its industrial production method. Background Technology

[0002] A grounding module is a grounding resistance reduction material used to improve grounding systems. Its main function is to increase the contact area with the soil to reduce the contact resistance, thereby improving the performance of the grounding system.

[0003] Existing grounding modules mostly use graphite, carbon materials, conductive polymers, and conductive cement as the main materials, supplemented by a metal conductive core. These modules suffer from drawbacks such as high cost, susceptibility to corrosion, and significant fluctuations in resistance reduction effectiveness depending on soil moisture levels. On the one hand, the production process of flexible graphite generates a large amount of scrap material (approximately 10%-15%), which is currently mainly disposed of through landfill, resulting in resource waste and environmental pollution. On the other hand, traditional grounding materials cannot maintain soil moisture in arid regions, leading to a seasonal increase in grounding resistance and affecting the stability of the power system. Reference 1 describes a water-collecting and moisture-retaining grounding module suitable for arid regions and its preparation method.

[0004] Reference 1: Chinese patent document with publication number CN107681288A.

[0005] Reference 1 describes a water-collecting and moisture-retaining grounding module suitable for arid regions and its preparation method. The water-collecting and moisture-retaining grounding module includes a flexible graphite grounding wire and a non-metallic module body covering the flexible graphite grounding wire. Both ends of the flexible graphite grounding wire extend outside the non-metallic module body. The non-metallic module body has multiple holes and / or channels dispersed inside. Each hole is filled with one water-absorbing resin particle, and each channel is filled with multiple water-absorbing resin particles. This invention possesses good moisture-retaining and water-collecting capabilities, which can improve the problem of severe water loss around the grounding grid in arid regions. It also possesses excellent properties such as acid and alkali resistance, corrosion resistance, high and low temperature resistance, rust resistance, stable electrical performance, and long service life.

[0006] This technical solution utilizes water-absorbing resin particles to absorb water and achieve a moisturizing effect. However, it relies on the dehydration and shrinkage of the hydrogel to create pores, resulting in random pore distribution and poor connectivity. Reference 2 describes a technical solution that utilizes the moisture-retaining and ion-exchange capabilities of bentonite to reduce grounding resistance.

[0007] Reference 2: Chinese patent document with publication number CN2665952Y.

[0008] Reference 2 describes a corrosion-resistant grounding device that solves the technical problems of high cost, short service life, easy aging and deterioration, and the need for frequent replacement in previous technologies. It includes a grounding electrode, characterized in that bentonite is arranged around the grounding electrode and the bentonite is in a moist state. However, this technology still has the following limitations:

[0009] (1) Conductivity bottleneck: When the bentonite content exceeds 25%, the resistivity of the material rises sharply to over 5 Ω·m, and the conductivity deteriorates drastically.

[0010] (2) Interface instability: Graphite has poor compatibility with bentonite and is prone to delamination when exposed to water, which damages the structural integrity.

[0011] (3) Performance contradiction: It is difficult to coordinate the improvement of water absorption and the optimization of conductivity, forming a core technology bottleneck;

[0012] (4) Resource limitations: It failed to simultaneously address the dual needs of high-value utilization of industrial solid waste and synergistic improvement of conductivity. Summary of the Invention

[0013] The purpose of this invention is to solve the above-mentioned technical problems existing in the prior art and to provide a water-absorbing and moisture-retaining long-lasting resistance-reducing grounding module and its industrial production method.

[0014] To address the shortcomings of the aforementioned technical problems, the present invention adopts the following technical solution:

[0015] A water-absorbing and moisture-retaining long-lasting resistance-reducing grounding module includes a grounding module body, a graphite-based flexible grounding strip, and a water-absorbing pipe;

[0016] The grounding module body is formed by pressing a mixture of graphite fragments, bentonite, and water glass.

[0017] One end of the graphite-based flexible grounding strip is placed inside the grounding module body;

[0018] One end of the water suction pipe is placed inside the grounding module body, and multiple water inlet micro-holes are distributed on the pipe body.

[0019] As a further optimization of the water-absorbing and moisture-retaining long-lasting resistance-reducing grounding module of the present invention: the graphite fragments are waste materials from the production process of flexible graphite, with a D50 of 0.8 ± 0.2 mm and a tap density ≥ 0.45 g / cm³. 3 Specific surface area is 3-5m² 2 / g.

[0020] As a further optimization of the water-absorbing and moisture-retaining long-lasting resistance-reducing grounding module of the present invention: the bentonite is modified sodium-based bentonite with CEC≥100mmol / 100g and interlayer spacing≥1.5nm.

[0021] As a further optimization of the water-absorbing and moisture-retaining long-lasting resistance-reducing grounding module of the present invention: the water glass is liquid water glass with a modulus of 2.2-3.4, a viscosity of 300-500 cP at room temperature, and a Na2O content ≥8%.

[0022] As a further optimization of the water-absorbing and moisture-retaining long-lasting resistance-reducing grounding module of the present invention: the material of the water-absorbing tube in step S3 is PLA / PHA blend.

[0023] This invention also provides an industrial production method for a water-absorbing and moisture-retaining long-lasting resistance-reducing grounding module, comprising the following steps:

[0024] S1, Raw material pretreatment

[0025] Graphite waste is first coarsely crushed to 2-4 mm, then pulverized to D50 = 0.8 ± 0.2 mm using an air jet mill, and ultrafine powder <0.1 μm is removed by cyclone separation. Finally, it is activated and dried to obtain activated graphite waste with a moisture content <0.5%, which is then ready for use.

[0026] Take bentonite and activate it at 110-130℃ for 1.5-2.5 hours to obtain activated bentonite for later use;

[0027] Water glass with moduli of 2.2-2.4, 2.6-2.8, and 3.2-3.4 were taken respectively, and a dispersant was added to the water glass. The mixture was stirred evenly to obtain three water glass with different moduli, which were then set aside for later use.

[0028] S2, Slurry Preparation

[0029] The core layer slurry is prepared by mixing 70% activated graphite waste, 20% bentonite, and 10% water glass with a modulus of 2.2-2.4 by weight.

[0030] Take 30% activated graphite waste, 50% bentonite, and 20% water glass with a modulus of 2.6-2.8 by weight percentage, and mix them thoroughly to obtain the transition layer slurry;

[0031] Take 10% activated graphite waste, 70% bentonite, and 20% water glass with a modulus of 3.2-3.4 by weight percentage, and mix them thoroughly to obtain the outer shell slurry;

[0032] S3, Molding Processing

[0033] The mold is first preheated, and then the outer shell slurry, transition layer slurry, core layer slurry, transition layer slurry and outer shell slurry are laid in the mold from bottom to top. Graphite-based flexible grounding strip is implanted in the core layer slurry. Finally, after pressing, demolding and curing, a grounding module body with graphite-based flexible grounding strip is obtained. A water suction pipe is inserted into the hole reserved in the grounding module body to obtain the grounding module.

[0034] The aforementioned layered structural design essentially decouples the three functional pathways—"current channels," "ion channels," and "moisture channels"—within a single module, then connects them through a transition layer to form a "funnel-shaped" electric field. The high resistivity of the outer shell converges the current density to the module body, preventing surface flashover. The transition layer further compresses the electric field, increasing the current density in the core layer region, thereby further reducing the overall grounding resistance of the module. Because the current density is concentrated in the core layer, the heat generation in the core layer increases, but the high thermal resistance of the transition layer inhibits heat diffusion to the outer shell layer. As a result, the module's temperature rise is lower than that of a non-layered module, improving long-term stability.

[0035] 30% graphite retains the electronically conductive network, while 50% bentonite provides abundant exchangeable cations. When fault currents or lightning currents are injected, the electron flow in the core layer couples with the ion flow in the transition layer, rapidly transferring transient charges to the surrounding soil and reducing transient ground potential rise.

[0036] The outer shell has a high bentonite content, which expands upon contact with water to form a dense hydrated gel layer, locking in moisture and slowly releasing it into the interior. The increased interface area between the outer shell and the soil (bentonite absorbs water and expands, microcracks close and open circulation) and the transition layer provide ion channels, avoiding the phenomenon of "moisture accumulation - increased resistance" (in porous grounding materials, localized moisture accumulation blocks ion (or electron) migration channels, leading to a reduction in the effective conductive cross-sectional area, resulting in the abnormal phenomenon of macroscopic resistance increasing instead of decreasing).

[0037] The outer shell layer has a water glass modulus of 3.2–3.4, exhibiting rapid condensation reaction and forming a dense silica-oxygen network within 30 minutes, resulting in high early strength—essentially encasing the module in a "ceramic armor." The core layer has a modulus of 2.2–2.4, with a slower reaction and lower cross-linking degree, forming a flexible gel with increased ultimate strain, capable of absorbing the instantaneous expansion during lightning current impacts. The transition layer has a modulus between the two (around 2.8), both binding the hard shell and gradually dissipating the deformation of the core layer, preventing interfacial delamination. As the interior continues to lose water and shrink, the hardened outer shell applies "circumferential pre-stress," essentially acting as a reinforcing girder around the core layer.

[0038] The activation process in step S1 is as follows: the coupling agent KH-550 is dissolved in ethanol and sprayed onto the graphite powder in a fluidized bed for activation. The fluidized bed operating temperature is 60℃ and the rotation speed is 300rpm.

[0039] The pressure adjustment in the final pressing step S3 is as follows: first, increase the pressure from 0MPa to 0.5MPa after 10 seconds, then increase the pressure to 5MPa after 10 seconds and hold the pressure for 30 seconds, then increase the pressure to 10MPa after 20 seconds and hold the pressure for 60 seconds, and finally increase the pressure to 18MPa after 30 seconds and hold the pressure for 4 minutes.

[0040] This invention also provides an industrial production method for a water-absorbing and moisture-retaining long-lasting resistance-reducing grounding module, comprising the following steps:

[0041] S1, Raw material pretreatment

[0042] Graphite waste is first coarsely crushed to 2-4 mm, then pulverized to D50 = 0.8 ± 0.2 mm using an air jet mill, and ultrafine powder <0.1 μm is removed by cyclone separation. Finally, it is activated and dried to obtain activated graphite waste with a moisture content <0.5%, which is then ready for use.

[0043] Take bentonite and activate it at 110-130℃ for 1.5-2.5 hours to obtain activated bentonite for later use;

[0044] Water glass with moduli of 2.2-2.4, 2.6-2.8 and 3.2-3.4 were taken respectively, and 0.1% of their weight of dispersant was added. The mixture was stirred evenly to obtain three types of water glass with different moduli for later use.

[0045] S2, Slurry Preparation

[0046] The core layer slurry is prepared by mixing 70% activated graphite waste, 20% bentonite, and 10% water glass with a modulus of 2.2-2.4 by weight.

[0047] Take 30% activated graphite waste, 50% bentonite, and 20% water glass with a modulus of 2.6-2.8 by weight percentage, and mix them thoroughly to obtain the transition layer slurry;

[0048] Take 10% activated graphite waste, 70% bentonite, and 20% water glass with a modulus of 3.2-3.4 by weight percentage, and mix them thoroughly to obtain the outer shell slurry;

[0049] S3, Molding Processing

[0050] The core layer slurry is poured into the molding mold cavity and a graphite-based flexible grounding strip is implanted. After pressing, demolding and curing, the core layer blank is obtained.

[0051] The transition layer slurry is poured into the molding mold cavity, and after pressing, demolding and curing, the transition layer blank is obtained.

[0052] The outer shell layer slurry is poured into the molding mold cavity, and after pressing, demolding and curing, the outer shell layer blank is obtained.

[0053] The blanks are stacked in the following order from bottom to top: outer shell blank, transition layer blank, core layer blank, transition layer blank, and outer shell blank. Water glass solution is applied between adjacent blanks as an adhesive. Finally, the blanks are cured under pressure to obtain a grounding module body with a graphite-based flexible grounding strip. A water suction pipe is inserted into the hole reserved in the grounding module body to obtain the grounding module.

[0054] In step S3, the thickness ratio of the core layer blank, the transition layer blank, and the outer shell layer blank is 4:2:1. The pressure for pressure curing is 0.5-2MPa, the holding time is 20-60min, and the curing temperature is 40-60℃.

[0055] The present invention has the following beneficial effects:

[0056] (1) Excellent resistance reduction stability: By constructing a ternary synergistic system of "graphite conductive network-water glass ion channel-bentonite water storage unit", the water suction pipe draws water and stores water into the module, so that the module can maintain a stable grounding resistance in drought or freeze-thaw environment. Experimental data show that its resistance reduction effect is 20% to 30% higher than that of traditional grounding modules, effectively solving the problem of resistance fluctuation caused by soil moisture changes.

[0057] (2) Long-lasting moisture retention function: Through the curved water suction pipe and the modified sodium bentonite, water is stored inside. Combined with the ion migration channel formed by the solidification of water glass, the soil moisture around the grounding body can be maintained for a long time, ensuring that the grounding resistance remains stable during seasonal changes. It is especially suitable for harsh environments such as drought and sandy soil.

[0058] (3) High-value utilization of industrial solid waste: Flexible graphite production waste is used as the main raw material. Through surface activation, particle size classification and interface optimization, 100% solid waste resource utilization is achieved, which reduces production costs and environmental pollution, and conforms to the concept of green manufacturing.

[0059] (4) Structural stability and durability: The gradient pressure molding process makes the bentonite sheets oriented, which enhances the density of the material and avoids delamination when exposed to water. At the same time, the three-dimensional conductive network formed by graphite fragments ensures long-term stable conductivity.

[0060] (5) Convenient construction and wide range of applications: The modules adopt standardized dimensions (adjustable by ±10%), which facilitates transportation and installation. They are suitable for various scenarios such as power systems, communication base stations, and lightning protection projects, and are particularly effective in areas with high resistivity soil. Attached Figure Description

[0061] Figure 1This is a schematic diagram of the structure of the water-absorbing and moisture-retaining long-lasting resistance-reducing grounding module of the present invention;

[0062] The diagram shows: 1. Grounding module body; 2. Graphite-based flexible grounding strip; 3. Water suction pipe. Detailed Implementation

[0063] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the content of the present invention is not limited to the following embodiments.

[0064] <Example 1>

[0065] An industrial production method for a water-absorbing and moisture-retaining long-lasting grounding module with reduced resistance includes the following steps:

[0066] S1, Raw material pretreatment

[0067] Take 10 kg of graphite waste, first crush it to 3 mm using a jaw crusher, then pulverize it to D50 = 0.85 mm using an air jet mill, and remove the ultrafine powder <0.1 μm by cyclone separation. Finally, it is activated and dried to obtain activated graphite waste with a moisture content <0.5% for later use.

[0068] The activation treatment is as follows: 200g of coupling agent KH-550 is dissolved in 1L of ethanol and sprayed onto the graphite powder in a fluidized bed for activation treatment. The working temperature of the fluidized bed is 60℃ and the rotation speed is 300rpm.

[0069] Take bentonite (modified sodium-based bentonite) and activate it at 120℃ for 2 hours to obtain activated bentonite for later use.

[0070] Water glass with moduli of 2.3, 2.7 and 3.3 were taken respectively, and 0.1% of dispersant (sodium hexametaphosphate dispersant) was added to the water glass. The mixture was stirred evenly to obtain water glass with three different moduli for later use.

[0071] S2, Slurry Preparation

[0072] Take 70% activated graphite waste, 20% bentonite and 10% water glass with a modulus of 2.3 by weight percentage and mix them thoroughly (planetary mixer (30 rpm revolution + 1200 rpm rotation), vacuum degree -0.08 MPa, mixing time 20 min) to obtain the core layer slurry.

[0073] Take 30% activated graphite waste, 50% bentonite and 20% water glass with a modulus of 2.7 by weight percentage and mix them thoroughly (planetary mixer (30 rpm revolution + 1200 rpm rotation), vacuum degree -0.08 MPa, mixing time 20 min) to obtain transition layer slurry.

[0074] Take 10% activated graphite waste, 70% bentonite and 20% water glass with a modulus of 3.3 by weight percentage and mix them thoroughly (planetary mixer (revolution 30 rpm + rotation 1200 rpm), vacuum degree -0.08 MPa, mixing time 20 min) to obtain the outer shell slurry.

[0075] S3, Molding Processing

[0076] The mold is first preheated (50℃), and then the outer shell slurry, transition layer slurry, core layer slurry, transition layer slurry and outer shell slurry are laid in the mold from bottom to top. Graphite-based flexible grounding strip is implanted in the core layer slurry. Finally, after pressing, demolding and curing (90% humidity, 25℃ curing box for 72 hours), a grounding module body with graphite-based flexible grounding strip is obtained. A water suction pipe is inserted into the reserved hole in the grounding module body to obtain the grounding module.

[0077] Graphite-based flexible grounding strips are a type of non-metallic conductive material made primarily of high-carbon graphite. They are manufactured into flat strip structures through processes such as expansion, weaving, and pressing, and represent existing technology.

[0078] The pressure adjustment for compression molding is as follows: first, increase the pressure from 0MPa to 0.5MPa after 10 seconds, then increase the pressure to 5MPa after 10 seconds and hold the pressure for 30 seconds, then increase the pressure to 10MPa after 20 seconds and hold the pressure for 60 seconds, and finally increase the pressure to 18MPa after 30 seconds and hold the pressure for 4 minutes.

[0079] The graphite-based flexible grounding strip is 1.3 meters long, and the grounding module is 800mm×400mm×100mm in length, width and height (of which, the thickness ratio of the outer shell layer, transition layer, core layer, transition layer and outer shell layer is 1:2:4:2:1).

[0080] The structure of the prepared grounding module is as follows Figure 1 As shown, the grounding module includes a grounding module body 1, a graphite-based flexible grounding strip 2, and a water suction pipe 3. The water suction pipe has multiple water inlet micro-holes distributed on its body.

[0081] <Example 2>

[0082] An industrial production method for a water-absorbing and moisture-retaining long-lasting grounding module with reduced resistance includes the following steps:

[0083] S1, Raw material pretreatment

[0084] Take 10 kg of graphite waste, first crush it to 2 mm using a jaw crusher, then pulverize it to D50 = 0.75 mm using an air jet mill, and remove the ultrafine powder <0.1 μm by cyclone separation. Finally, it is activated and dried to obtain activated graphite waste with a moisture content <0.5% for later use.

[0085] The activation treatment is as follows: 200g of coupling agent KH-550 is dissolved in 1L of ethanol and sprayed onto the graphite powder in a fluidized bed for activation treatment. The working temperature of the fluidized bed is 60℃ and the rotation speed is 300rpm.

[0086] Take bentonite (modified sodium-based bentonite) and activate it at 110℃ for 2.5h to obtain activated bentonite for later use.

[0087] Water glass with moduli of 2.2, 2.8 and 3.2 were taken respectively, and 0.1% of dispersant (sodium hexametaphosphate dispersant) was added to the water glass. The mixture was stirred evenly to obtain water glass with three different moduli for later use.

[0088] S2, Slurry Preparation

[0089] Take 70% activated graphite waste, 20% bentonite, and 10% water glass with a modulus of 2.2 by weight percentage and mix them thoroughly (planetary mixer (30 rpm revolution + 1200 rpm rotation), vacuum degree -0.08 MPa, mixing time 20 min) to obtain the core layer slurry.

[0090] Take 30% activated graphite waste, 50% bentonite and 20% water glass with a modulus of 2.8 by weight percentage and mix them thoroughly (planetary mixer (30 rpm revolution + 1200 rpm rotation), vacuum degree -0.08 MPa, mixing time 20 min) to obtain transition layer slurry.

[0091] Take 10% activated graphite waste, 70% bentonite and 20% water glass with a modulus of 3.2 by weight percentage and mix them thoroughly (planetary mixer (revolution 30 rpm + rotation 1200 rpm), vacuum degree -0.08 MPa, mixing time 20 min) to obtain the outer shell slurry.

[0092] S3, Molding Processing

[0093] The mold is first preheated (50℃), and then the outer shell slurry, transition layer slurry, core layer slurry, transition layer slurry and outer shell slurry are laid in the mold from bottom to top. Graphite-based flexible grounding strip is implanted in the core layer slurry. Finally, after pressing, demolding and curing (90% humidity, 25℃ curing box for 72 hours), a grounding module body with graphite-based flexible grounding strip is obtained. A water suction pipe is inserted into the reserved hole in the grounding module body to obtain the grounding module.

[0094] Graphite-based flexible grounding strips are a type of non-metallic conductive material made primarily of high-carbon graphite. They are manufactured into flat strip structures through processes such as expansion, weaving, and pressing, and represent existing technology.

[0095] The pressure adjustment for compression molding is as follows: first, increase the pressure from 0MPa to 0.5MPa after 10 seconds, then increase the pressure to 5MPa after 10 seconds and hold the pressure for 30 seconds, then increase the pressure to 10MPa after 20 seconds and hold the pressure for 60 seconds, and finally increase the pressure to 18MPa after 30 seconds and hold the pressure for 4 minutes.

[0096] The graphite-based flexible grounding strip is 1.2 meters long, and the grounding module has dimensions of 720mm×440mm×90mm (where the thickness ratio of the outer shell, transition layer, core layer, transition layer and outer shell is 1:2:4:2:1).

[0097] <Example 3>

[0098] An industrial production method for a water-absorbing and moisture-retaining long-lasting grounding module with reduced resistance includes the following steps:

[0099] S1. Raw material pretreatment

[0100] Take 10 kg of graphite waste, first crush it to 4 mm using a jaw crusher, then pulverize it to D50 = 0.95 mm using an air jet mill, and remove the ultrafine powder <0.1 μm by cyclone separation. Finally, it is activated and dried to obtain activated graphite waste with a moisture content <0.5% for later use.

[0101] The activation treatment is as follows: 200g of coupling agent KH-550 is dissolved in 1L of ethanol and sprayed onto the graphite powder in a fluidized bed for activation treatment. The working temperature of the fluidized bed is 60℃ and the rotation speed is 300rpm.

[0102] Take bentonite (modified sodium-based bentonite) and activate it at 130℃ for 1.5h to obtain activated bentonite for later use.

[0103] Water glass with moduli of 2.4, 2.6 and 3.4 were taken respectively, and 0.1% of dispersant (sodium hexametaphosphate dispersant) was added to the water glass. The mixture was stirred evenly to obtain water glass with three different moduli for later use.

[0104] S2, Slurry Preparation

[0105] Take 70% activated graphite waste, 20% bentonite, and 10% water glass with a modulus of 2.4 by weight percentage and mix them thoroughly (planetary mixer (revolution 30 rpm + rotation 1200 rpm), vacuum degree -0.08 MPa, mixing time 20 min) to obtain the core layer slurry.

[0106] Take 30% activated graphite waste, 50% bentonite and 20% water glass with a modulus of 2.6 by weight percentage and mix them thoroughly (planetary mixer (30 rpm revolution + 1200 rpm rotation), vacuum degree -0.08 MPa, mixing time 20 min) to obtain transition layer slurry.

[0107] Take 10% activated graphite waste, 70% bentonite and 20% water glass with a modulus of 3.4 by weight percentage and mix them thoroughly (planetary mixer (revolution 30 rpm + rotation 1200 rpm), vacuum degree -0.08 MPa, mixing time 20 min) to obtain the outer shell slurry.

[0108] S3, Molding Processing

[0109] The mold is first preheated (50℃), and then the outer shell slurry, transition layer slurry, core layer slurry, transition layer slurry and outer shell slurry are laid in the mold from bottom to top. Graphite-based flexible grounding strip is implanted in the core layer slurry. Finally, after pressing, demolding and curing (90% humidity, 25℃ curing box for 72 hours), a grounding module body with graphite-based flexible grounding strip is obtained. A water suction pipe is inserted into the reserved hole in the grounding module body to obtain the grounding module.

[0110] Graphite-based flexible grounding strips are a type of non-metallic conductive material made primarily of high-carbon graphite. They are manufactured into flat strip structures through processes such as expansion, weaving, and pressing, and represent existing technology.

[0111] The pressure adjustment for compression molding is as follows: first, increase the pressure from 0MPa to 0.5MPa after 10 seconds, then increase the pressure to 5MPa after 10 seconds and hold the pressure for 30 seconds, then increase the pressure to 10MPa after 20 seconds and hold the pressure for 60 seconds, and finally increase the pressure to 18MPa after 30 seconds and hold the pressure for 4 minutes.

[0112] The graphite-based flexible grounding strip is 1.5 meters long, and the grounding module has dimensions of 880mm×360mm×110mm (where the thickness ratio of the outer shell, transition layer, core layer, transition layer and outer shell is 1:2:4:2:1).

[0113] <Example 4>

[0114] An industrial production method for a water-absorbing and moisture-retaining long-lasting grounding module with reduced resistance includes the following steps:

[0115] S1, Raw material pretreatment

[0116] Take 10 kg of graphite waste, first crush it to 3 mm using a jaw crusher, then pulverize it to D50 = 0.85 mm using an air jet mill, and remove the ultrafine powder <0.1 μm by cyclone separation. Finally, it is activated and dried to obtain activated graphite waste with a moisture content <0.5% for later use.

[0117] The activation treatment is as follows: 200g of coupling agent KH-550 is dissolved in 1L of ethanol and sprayed onto the graphite powder in a fluidized bed for activation treatment. The working temperature of the fluidized bed is 60℃ and the rotation speed is 300rpm.

[0118] Take bentonite (modified sodium-based bentonite) and activate it at 120℃ for 2 hours to obtain activated bentonite for later use.

[0119] Water glass with moduli of 2.3, 2.7 and 3.3 were taken respectively, and 0.1% of dispersant (sodium hexametaphosphate dispersant) was added to the water glass. The mixture was stirred evenly to obtain water glass with three different moduli for later use.

[0120] S2, Slurry Preparation

[0121] Take 70% activated graphite waste, 20% bentonite and 10% water glass with a modulus of 2.3 by weight percentage and mix them thoroughly (planetary mixer (30 rpm revolution + 1200 rpm rotation), vacuum degree -0.08 MPa, mixing time 20 min) to obtain the core layer slurry.

[0122] Take 30% activated graphite waste, 50% bentonite and 20% water glass with a modulus of 2.7 by weight percentage and mix them thoroughly (planetary mixer (30 rpm revolution + 1200 rpm rotation), vacuum degree -0.08 MPa, mixing time 20 min) to obtain transition layer slurry.

[0123] Take 10% activated graphite waste, 70% bentonite and 20% water glass with a modulus of 3.3 by weight percentage and mix them thoroughly (planetary mixer (revolution 30 rpm + rotation 1200 rpm), vacuum degree -0.08 MPa, mixing time 20 min) to obtain the outer shell slurry.

[0124] S3, Molding Processing

[0125] The core layer slurry is poured into the molding mold cavity and a graphite-based flexible grounding strip is implanted. After pressing, demolding and curing, the core layer blank is obtained.

[0126] The transition layer slurry is poured into the molding mold cavity, and after pressing, demolding and curing, the transition layer blank is obtained.

[0127] The outer shell layer slurry is poured into the molding mold cavity, and after pressing, demolding and curing, the outer shell layer blank is obtained.

[0128] The blanks are stacked from bottom to top in the following order: outer shell blank, transition layer blank, core layer blank, transition layer blank, and outer shell blank (the thickness ratio of the core layer blank, transition layer blank, and outer shell blank is 4:2:1). Water glass solution is coated between adjacent blanks as an adhesive. Finally, the blanks are cured under pressure (pressure of 1.0 MPa, holding time of 45 min, and curing temperature of 50℃) to obtain the grounding module body with graphite-based flexible grounding strip. A water suction pipe is inserted into the hole reserved in the grounding module body to obtain the grounding module.

[0129] The graphite-based flexible grounding strip is 1.3 meters long, and the grounding module is 800mm×400mm×100mm in length, width and height (of which, the thickness ratio of the outer shell layer, transition layer, core layer, transition layer and outer shell layer is 1:2:4:2:1).

[0130] <Example 5>

[0131] An industrial production method for a water-absorbing and moisture-retaining long-lasting grounding module with reduced resistance includes the following steps:

[0132] S1, Raw material pretreatment

[0133] Take 10 kg of graphite waste, first crush it to 2 mm using a jaw crusher, then pulverize it to D50 = 0.75 mm using an air jet mill, and remove the ultrafine powder <0.1 μm by cyclone separation. Finally, it is activated and dried to obtain activated graphite waste with a moisture content <0.5% for later use.

[0134] The activation treatment is as follows: 200g of coupling agent KH-550 is dissolved in 1L of ethanol and sprayed onto the graphite powder in a fluidized bed for activation treatment. The working temperature of the fluidized bed is 60℃ and the rotation speed is 300rpm.

[0135] Take bentonite (modified sodium-based bentonite) and activate it at 110℃ for 2.5h to obtain activated bentonite for later use.

[0136] Water glass with moduli of 2.2, 2.8 and 3.2 were taken respectively, and 0.1% of dispersant (sodium hexametaphosphate dispersant) was added to the water glass. The mixture was stirred evenly to obtain water glass with three different moduli for later use.

[0137] S2, Slurry Preparation

[0138] Take 70% activated graphite waste, 20% bentonite, and 10% water glass with a modulus of 2.2 by weight percentage and mix them thoroughly (planetary mixer (30 rpm revolution + 1200 rpm rotation), vacuum degree -0.08 MPa, mixing time 20 min) to obtain the core layer slurry.

[0139] Take 30% activated graphite waste, 50% bentonite and 20% water glass with a modulus of 2.8 by weight percentage and mix them thoroughly (planetary mixer (30 rpm revolution + 1200 rpm rotation), vacuum degree -0.08 MPa, mixing time 20 min) to obtain transition layer slurry.

[0140] Take 10% activated graphite waste, 70% bentonite and 20% water glass with a modulus of 3.2 by weight percentage and mix them thoroughly (planetary mixer (revolution 30 rpm + rotation 1200 rpm), vacuum degree -0.08 MPa, mixing time 20 min) to obtain the outer shell slurry.

[0141] S3, Molding Processing

[0142] The core layer slurry is poured into the molding mold cavity and a graphite-based flexible grounding strip is implanted. After pressing, demolding and curing, the core layer blank is obtained.

[0143] The transition layer slurry is poured into the molding mold cavity, and after pressing, demolding and curing, the transition layer blank is obtained.

[0144] The outer shell layer slurry is poured into the molding mold cavity, and after pressing, demolding and curing, the outer shell layer blank is obtained.

[0145] The blanks are stacked in the following order from bottom to top: outer shell blank, transition layer blank, core layer blank, transition layer blank, and outer shell blank (the thickness ratio of the core layer blank, transition layer blank, and outer shell blank is 4:2:1). Water glass solution is coated between adjacent blanks as an adhesive. Finally, the blanks are cured under pressure (pressure of 2MPa, holding time of 20min, curing temperature of 40℃) to obtain the grounding module body with graphite-based flexible grounding strip. A water suction pipe is inserted into the hole reserved in the grounding module body to obtain the grounding module.

[0146] The graphite-based flexible grounding strip is 1.3 meters long, and the grounding module is 800mm×400mm×100mm in length, width and height (of which, the thickness ratio of the outer shell layer, transition layer, core layer, transition layer and outer shell layer is 1:2:4:2:1).

[0147] <Example 6>

[0148] An industrial production method for a water-absorbing and moisture-retaining long-lasting grounding module with reduced resistance includes the following steps:

[0149] S1, Raw material pretreatment

[0150] Take 10 kg of graphite waste, first crush it to 2 mm using a jaw crusher, then pulverize it to D50 = 0.75 mm using an air jet mill, and remove the ultrafine powder <0.1 μm by cyclone separation. Finally, it is activated and dried to obtain activated graphite waste with a moisture content <0.5% for later use.

[0151] The activation treatment is as follows: 200g of coupling agent KH-550 is dissolved in 1L of ethanol and sprayed onto the graphite powder in a fluidized bed for activation treatment. The working temperature of the fluidized bed is 60℃ and the rotation speed is 300rpm.

[0152] Take bentonite (modified sodium-based bentonite) and activate it at 110℃ for 2.5h to obtain activated bentonite for later use.

[0153] Water glass with moduli of 2.2, 2.8 and 3.2 were taken respectively, and 0.1% of dispersant (sodium hexametaphosphate dispersant) was added to the water glass. The mixture was stirred evenly to obtain water glass with three different moduli for later use.

[0154] S2, Slurry Preparation

[0155] Take 70% activated graphite waste, 20% bentonite, and 10% water glass with a modulus of 2.2 by weight percentage and mix them thoroughly (planetary mixer (30 rpm revolution + 1200 rpm rotation), vacuum degree -0.08 MPa, mixing time 20 min) to obtain the core layer slurry.

[0156] Take 30% activated graphite waste, 50% bentonite and 20% water glass with a modulus of 2.8 by weight percentage and mix them thoroughly (planetary mixer (30 rpm revolution + 1200 rpm rotation), vacuum degree -0.08 MPa, mixing time 20 min) to obtain transition layer slurry.

[0157] Take 10% activated graphite waste, 70% bentonite and 20% water glass with a modulus of 3.2 by weight percentage and mix them thoroughly (planetary mixer (revolution 30 rpm + rotation 1200 rpm), vacuum degree -0.08 MPa, mixing time 20 min) to obtain the outer shell slurry.

[0158] S3, Molding Processing

[0159] The core layer slurry is poured into the molding mold cavity and a graphite-based flexible grounding strip is implanted. After pressing, demolding and curing, the core layer blank is obtained.

[0160] The transition layer slurry is poured into the molding mold cavity, and after pressing, demolding and curing, the transition layer blank is obtained.

[0161] The outer shell layer slurry is poured into the molding mold cavity, and after pressing, demolding and curing, the outer shell layer blank is obtained.

[0162] The blanks are stacked in the following order from bottom to top: outer shell blank, transition layer blank, core layer blank, transition layer blank, and outer shell blank (the thickness ratio of the core layer blank, transition layer blank, and outer shell blank is 4:2:1). Water glass solution is coated between adjacent blanks as an adhesive. Finally, the blanks are cured under pressure (pressure of 0.5 MPa, holding time of 60 min, and curing temperature of 60℃) to obtain the grounding module body with graphite-based flexible grounding strip. A water suction pipe is inserted into the hole reserved in the grounding module body to obtain the grounding module.

[0163] The graphite-based flexible grounding strip is 1.3 meters long, and the grounding module is 800mm×400mm×100mm in length, width and height (of which, the thickness ratio of the outer shell layer, transition layer, core layer, transition layer and outer shell layer is 1:2:4:2:1).

[0164] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A water-absorbing and moisture-retaining long-acting resistance-reducing ground module, characterized by: The grounding module comprises a grounding module body, a graphite-based flexible grounding belt and a water absorption pipe; The grounding module body is obtained by mixing graphite scraps, bentonite and water glass and then being pressed and formed; One end of the graphite-based flexible grounding belt is arranged in the grounding module body; One end of the water absorption pipe is arranged in the grounding module body, and a plurality of water inlet micropores are distributed on the pipe body of the water absorption pipe.

2. The water-absorbing and moisture-preserving long-acting resistance-reducing ground module according to claim 1, characterized in that: The graphite chips are waste material in the production of flexible graphite, the graphite chips D50 = 0.8 ± 0.2 mm, tap density ≥ 0.45 g / cm 3 , and the specific surface area is 3-5 m 2 / g.

3. The water-absorbing and moisture-preserving long-acting resistance-reducing ground module according to claim 1, characterized in that: The bentonite is modified sodium-based bentonite, CEC≥100 mmol / 100g, and the interlayer spacing is≥1.5 nm.

4. The water-absorbing and moisture-preserving long-acting resistance-reducing ground module according to claim 1, characterized in that: The water glass is liquid water glass, the modulus of the water glass is 2.2-3.4, the viscosity at room temperature is 300-500 cP, and the Na2O content is≥8%.

5. The water-absorbing and moisture-preserving long-acting resistance-reducing ground module according to claim 1, characterized in that: The material of the water absorption pipe in the step S3 is PLA / PHA blend.

6. An industrialized production method of a water-absorbing and moisture-preserving long-acting resistance-reducing ground module, characterized in that: The method comprises the following steps: S1, raw material pretreatment Take graphite waste, first coarsely crush to 2-4 mm, then use air flow mill to crush to D50=0.8±0.2 mm, and remove ultra-fine powder less than 0.1 μm through cyclone separation, finally activate and dry to obtain activated graphite waste with water content less than 0.5%, for standby; Take bentonite, activate at a temperature of 110-130℃ for 1.5-2.5h to obtain activated bentonite, for standby; Take water glass with modulus of 2.2-2.4, 2.6-2.8 and 3.2-3.4 respectively, mix dispersant into the water glass, and stir uniformly to obtain three kinds of water glass with different modulus, for standby; S2, slurry preparation Take activated graphite waste 70%, bentonite 20% and water glass with modulus of 2.2-2.4 10% according to weight percentage, mix well by stirring to obtain core layer slurry; Take activated graphite waste 30%, bentonite 50% and water glass with modulus of 2.6-2.8 20% according to weight percentage, mix well by stirring to obtain transition layer slurry; Take activated graphite waste 10%, bentonite 70% and water glass with modulus of 3.2-3.4 20% according to weight percentage, mix well by stirring to obtain shell layer slurry; S3, forming processing The mold is preheated first, then the shell layer slurry, the transition layer slurry, the core layer slurry, the transition layer slurry and the shell layer slurry are laid in the mold from bottom to top in turn, the graphite-based flexible grounding belt is implanted in the core layer slurry, and finally the grounding module body with graphite-based flexible grounding belt is obtained by pressing and forming, demolding and curing, and the water absorption pipe is inserted into the reserved hole of the grounding module body, thereby obtaining the grounding module.

7. The industrialized production method of the water-absorbing and moisture-preserving long-acting resistance-reducing ground module according to claim 6, characterized in that: The activation treatment in step S1 is specifically as follows: the coupling agent KH-550 is dissolved in ethanol, and the graphite powder is activated by spraying in the fluidized bed, the working temperature of the fluidized bed is 60℃, and the rotation speed is 300 rpm.

8. The industrialized production method of the water-absorbing and moisture- preserving long-acting resistance-reducing ground module according to claim 6, characterized in that: The pressure adjustment of the final pressing and forming in step S3 is as follows: the pressure is first increased from 0 MPa to 0.5 MPa for 10 s, then increased to 5 MPa for 10 s and kept for 30 s, then increased to 10 MPa for 20 s and kept for 60 s, and finally increased to 18 MPa for 30 s and kept for 4 min.

9. A method for industrialized production of a water-absorbing and moisture- preserving long-acting resistance-reducing ground module, characterized in that: The method comprises the following steps: S1, raw material pretreatment Take graphite waste, first roughly crush to 2-4 mm, then use air flow mill to crush to D50=0.8±0.2 mm, and remove ultra-fine powder <0.1 μm through cyclone separation, finally carry out activation and drying treatment to obtain activated graphite waste with water content <0.5%, ready for use; Take bentonite, activate at 110-130 ℃ for 1.5-2.5 h to obtain activated bentonite, ready for use; Take water glass with modulus of 2.2-2.4, 2.6-2.8 and 3.2-3.4 respectively, mix 0.1% dispersant by weight, stir uniformly to obtain three kinds of water glass with different modulus, ready for use; S2, slurry preparation Take activated graphite waste 70%, bentonite 20% and water glass with modulus of 2.2-2.4 10% by weight, stir to mix thoroughly to obtain core layer slurry; Take activated graphite waste 30%, bentonite 50% and water glass with modulus of 2.6-2.8 20% by weight, stir to mix thoroughly to obtain transition layer slurry; Take activated graphite waste 10%, bentonite 70% and water glass with modulus of 3.2-3.4 20% by weight, stir to mix thoroughly to obtain shell layer slurry; S3, forming processing Pour the core layer slurry into the forming mold cavity and implant the graphite-based flexible grounding strip, and carry out pressing forming, demolding and curing to obtain the core layer body; Pour the transition layer slurry into the forming mold cavity, and carry out pressing forming, demolding and curing to obtain the transition layer body; Pour the shell layer slurry into the forming mold cavity, and carry out pressing forming, demolding and curing to obtain the shell layer body; Stack the layer bodies from bottom to top in the order of shell layer body, transition layer body, core layer body, transition layer body and shell layer body, coat water glass solution as adhesive between adjacent bodies, and finally carry out pressure curing to obtain the grounding module body with graphite-based flexible grounding strip, insert the water absorption pipe into the reserved hole of the grounding module body to obtain the grounding module.

10. The industrialized production method of the water-absorbing and moisture- preserving long-acting resistance-reducing ground module according to claim 9, characterized in that: The thickness ratio of the core layer body, the transition layer body and the shell layer body in step S3 is 4:2:1, the pressure curing pressure is 0.5-2 MPa, the pressure holding time is 20-60 min, and the curing temperature is 40-60 ℃.

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