Multi-layer cooperative sealing and anticorrosion structure of outer edge plate of storage tank and construction method thereof

Abstract

The application discloses a kind of multilayer synergic sealing anticorrosion structure of tank outer edge plate and its construction method, it is related to the anticorrosion sealing technical field of tank edge plate in petroleum, petrochemical and other industries, comprising: sealing isolation layer, by high-density polyethylene plate is formed, the high-density polyethylene plate is fixed on the cement base platform of tank by plate adhesive;Heterogeneous material bonding interface, by A glue coated in the lower part of tank wall plate is formed;Elastic fusion body, filled in the gap between tank bottom plate outer edge plate, tank wall plate and the high-density polyethylene plate, the elastic fusion body is made by rubber particle after interface agent soaking control dry and A glue mixing;Surface protection layer of B glue composition.The sealing anticorrosion structure of the application has strong dynamic adaptability, reduces construction difficulty, enhances environmental adaptability, is convenient for maintenance detection, and has significant economic and social benefits.

Description

Technical Field

[0001] This invention relates to the field of corrosion protection and sealing technology for the edge plates of storage tanks in various industries such as petroleum and petrochemicals, and in particular to a multi-layer synergistic sealing and corrosion protection structure for the outer edge plates of storage tanks and its construction method. Background Technology

[0002] Vertical cylindrical steel storage tanks are core equipment for material storage in industries such as petroleum, chemical, and grain and oil reserves. The outer edge plate area where the tank bottom meets the tank wall is subjected to multiple effects over a long period, including alternating wet and dry conditions, temperature cycles, load fluctuations, and ground settlement, making it a critical weak point in corrosion protection. Statistics show that approximately 80% of storage tank corrosion failures originate from edge plate corrosion, with most of these directly related to the failure of the outer edge plate's sealing and corrosion protection.

[0003] To address these issues, the industry has developed various sealing and corrosion protection technologies for the outer edges of storage tanks. Early technologies primarily used rigid materials such as asphalt and cement mortar. These materials have poor elasticity, cannot adapt to the deformation of storage tanks during operation, and are prone to cracking and water leakage in the short term, resulting in a short protective lifespan. Subsequent developments, such as epoxy fiberglass cloth and rubber asphalt, are transitional elastic materials. While they offer some elasticity, they suffer from poor adhesion to irregularly shaped joints and limited weather resistance. Currently, mainstream composite protection technologies, such as CTPU elastic polyurethane, petrolatum mortar coating, and viscoelastic sealant systems, still have drawbacks including material compatibility issues, difficulty in controlling construction quality, insufficient adaptability to extreme environments, and inconvenience in maintenance and inspection.

[0004] Therefore, how to provide a sealing and corrosion protection technology for the outer edge plate of storage tanks that can combine high elastic deformation adaptability, long-term sealing and corrosion protection, convenient construction and easy maintenance is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] In order to overcome the above-mentioned defects in the prior art, the present invention provides a multi-layer synergistic sealing and anti-corrosion structure for the outer edge plate of a storage tank and its construction method.

[0006] The technical solution adopted by this invention to solve its technical problem is a sealing and corrosion-resistant structure for the outer edge plate of a storage tank, comprising:

[0007] The sealing and isolation layer is made of high-density polyethylene board (6), which is fixed to the cement base (1) of the storage tank by board adhesive;

[0008] The heterogeneous material bonding interface (4) is composed of A glue coated on the lower part of the tank wall plate (3);

[0009] The elastic fusion body (7) fills the gap between the outer edge plate (2) of the tank bottom plate, the tank wall plate (3) and the high-density polyethylene plate (6). The elastic fusion body (7) is made of rubber particles soaked in an interface agent and dried and mixed with A glue.

[0010] The surface protective layer is composed of B-type adhesive coated on the outer side of the high-density polyethylene plate (6), the outer edge slope of the elastic fusion body (7), and the tank wall plate (3) at a certain height.

[0011] Furthermore, the high-density polyethylene board (6) protruding 10 mm from the edge of the cement base (1).

[0012] Furthermore, the heterogeneous material bonding interface (4) is coated on the lower part of the tank wall plate (3) within a range of 100mm-150mm upward from the tank edge plate (2), with a coating thickness of 1.5mm.

[0013] Furthermore, the density of the elastic fusion body (7) after filling and compaction is ≥1.2g / cm³, and the filling surface forms a slope that is higher inside and lower outside.

[0014] Furthermore, in the surface protective layer, the thickness of the B-type adhesive coated on the outer side of the high-density polyethylene plate (6), the outer edge slope of the elastic fusion body (7), and the tank wall plate (3) is 3 mm.

[0015] This invention also provides a construction method for the above-mentioned sealing and corrosion protection structure of the outer edge plate of the storage tank, comprising the following steps:

[0016] S1. Base surface pretreatment: Clean the tank wall, exposed edge plate (2) and cement base (1) to remove loose rust, oil and dust;

[0017] S2. Construction of sealing and isolation layer: Apply the adhesive of the board to the outer edge of the cement base (1) and the bonding surface of the high-density polyethylene board (6), let it stand until it is surface dry, and then paste the high-density polyethylene board (6) to the preset position of the cement base (1).

[0018] S3. Construction of heterogeneous material bonding interface (4): Apply the A adhesive evenly within a predetermined height range at the bottom of the tank wall;

[0019] S4. Preparation and filling of elastic fusion body (7): The rubber particles are soaked in the interface agent and then dried. The dried rubber particles are mixed with the A glue in proportion and stirred. The mixed rubber particles are filled into the gap between the outer edge plate (2) of the bottom plate of the storage tank, the wall plate (3) of the storage tank and the high-density polyethylene plate (6), and then compacted and smoothed.

[0020] S5. Surface protection construction: Apply the B adhesive evenly to the outer side of the high-density polyethylene plate (6), the outer edge slope of the elastic fusion body (7), and the tank wall plate (3) at a certain height.

[0021] Furthermore, in step S1, the pretreatment of the substrate adopts the lowest St2 or Sa1 level rust removal standard.

[0022] Furthermore, in step S2, the adhesive for the board is allowed to stand until it is surface dry for 3-5 minutes.

[0023] Furthermore, in step S41, the rubber particles have a particle size of 2-4 mm and are soaked in the interface agent for 30 minutes.

[0024] The beneficial effects of this invention are:

[0025] 1. The technical solution of this invention significantly improves dynamic adaptability: the elastic design of the bonding interface between the elastic fusion body and the heterogeneous material can adapt to the radial expansion and contraction and plastic warping of the tank edge plate, solving the defects of existing rigid materials being prone to cracking and flexible materials lacking resilience.

[0026] 2. The technical solution of this invention significantly reduces the difficulty of construction: it adopts the Sa1 or St2 grade "no need for complete rust removal" base surface treatment standard, avoiding the stringent requirements of existing technology for Sa2.5 grade rust removal, and improving construction efficiency by more than 40%; moreover, the construction quality is less affected by the professionalism of the personnel, and the pass rate is increased to more than 95%.

[0027] 3. The technical solution of this invention has enhanced adaptability to extreme environments: Through material system optimization, the protection life can reach more than 15 years in coastal high salt spray environments, chemical zone acid and alkali media, and extreme cold and temperature change environments, far exceeding traditional rigid materials (<3 years) and existing composite protection technologies (5~8 years). At the same time, the insulation characteristics of the surface protective layer and the elastic fusion body can reduce stray current interference and reduce the cathodic protection potential fluctuation range by 60%.

[0028] 4. The technical solution of this invention improves the convenience of maintenance and inspection: The integrated surface protection structure has no hidden leakage channels, and early hidden dangers can be detected by conventional visual inspection, improving the inspection efficiency by 70%; if local maintenance is required, the peelable and fusion characteristics of (B glue) and high-density polyethylene board shorten the maintenance and cleaning time to 1 / 5 of that of traditional petrolatum-based materials, reducing maintenance costs by 60%.

[0029] 5. The technical solution of this invention has significant economic and social benefits: the construction cost of sealing and anti-corrosion on the outer edge of a single 100,000 m³ storage tank is reduced by 30% compared with the existing CTPU system. Combined with a protection life of more than 15 years, the total life cycle cost is reduced by more than 55%, which greatly reduces the risk of corrosion and leakage of storage tanks, reduces material loss and environmental pollution, and can reduce the annual production stoppage loss caused by corrosion by about RMB 200,000 per unit, while reducing environmental risks such as heavy metal pollution.

[0030] 6. In the technology of this invention, when a local base plate or wall panel needs to be inspected or repaired, the corresponding sealing and anti-corrosion structure of the part to be inspected or repaired can be cut and removed. After the inspection or repair is completed, new material is added according to the preparation method of the sealing and anti-corrosion structure. The newly added sealing and anti-corrosion structure material can be fused and connected with the original sealing and anti-corrosion structure material without cracks, which effectively reduces the production cost of enterprises and improves the maintenance efficiency. Attached Figure Description

[0031] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0032] Figure 1 This is a schematic diagram of a multi-layer synergistic sealing and corrosion protection structure for the outer edge plate of a storage tank according to the present invention;

[0033] In the picture:

[0034] 1. Cement base, 2. Edge plate, 3. Tank wall plate, 4. Heterogeneous material bonding interface, 5. Board adhesive, 6. High-density polyethylene board, 7. Elastic fusion body, 8. Protective surface layer. Detailed Implementation

[0035] To more clearly illustrate the technical solution of the present invention, the present invention will be further described below with reference to the accompanying drawings. Obviously, the drawings described below are only one embodiment of the present invention. For those skilled in the art, other embodiments can be obtained based on these drawings and embodiments without creative effort, and all of them fall within the protection scope of the present invention.

[0036] This embodiment takes a 100,000 cubic meter vertical cylindrical steel storage tank as an example, and describes the sealing and anti-corrosion construction of its outer edge plate 2. The outer edge plate 2 of the storage tank is 12mm thick, the cement base 1 is 300mm wide, and the slope angle is 5-5.5°.

[0037] 1. Material preparation:

[0038] High-density polyethylene sheet 6 (HDPE sheet): 10mm thick, 100mm wide;

[0039] Board adhesive: Use a single-component adhesive;

[0040] Glue A: Made with highly elastic, high and low temperature resistant, corrosion resistant, and UV resistant silicone components;

[0041] Glue B: Made with silicone components that have a high thixotropic index, excellent weather resistance, corrosion resistance, and UV resistance;

[0042] Rubber granules: granules with a particle size of 2-4mm, made from high-elasticity materials such as waste rubber hoses and inner tubes;

[0043] Interface agent: Use a special soaking agent;

[0044] Auxiliary tools: wire brush, scraper, mixer, scraper, etc.

[0045] 2. Construction steps:

[0046] S1. Base surface pretreatment:

[0047] Tank wall cleaning: Use a wire brush to remove rust from the lower part of the tank wall (150mm from the edge plate 2 of the tank), remove loose rust, oil and dust from the surface, and the cleanliness of the treated surface should meet the Sa1 or St2 standard.

[0048] Cleaning of exposed edge plate 2: The same method is used to clean the exposed part of the outer edge plate 2 of the storage tank.

[0049] Cleaning of cement base 1: Use a scraper to remove laitance, dust and debris from the surface of cement base 1, and blow it clean with high-pressure air to ensure that the surface is dry and clean.

[0050] This invention adopts the Sa1 or St2 grade "no need for thorough rust removal" base surface treatment standard, avoiding the stringent requirements of existing technology for Sa2.5 grade rust removal, improving construction efficiency by more than 40%; and the construction quality is less affected by the professionalism of the personnel, with the pass rate increased to more than 95%.

[0051] S2. Construction of the sealing and isolation layer:

[0052] Apply the adhesive evenly to the bonding surfaces of the high-density polyethylene (HDPE) sheet 6. Simultaneously, apply the same thickness of adhesive to a 90mm wide area along the outer edge of the cement base 1. After application, allow it to stand for approximately 3 minutes until the adhesive reaches a surface-dry state where it is no longer sticky to the touch. Then, align and adhere the HDPE sheet 6 to the predetermined position on the cement base 1, ensuring that the HDPE sheet 6 protrudes 10mm beyond the edge of the cement base 1. After adhesion, gently tap and compact it with a rubber mallet to remove air bubbles and ensure a firm bond.

[0053] S3. Construction of heterogeneous material bonding interface 4:

[0054] Apply A adhesive evenly to the tank wall surface 100mm above the outer edge plate 2 of the tank bottom plate using a scraper. The coating thickness is 1.5mm, forming a heterogeneous material bonding interface 4. Ensure that there are no bubbles or missed areas during the coating process.

[0055] S4. Preparation and filling of elastic fusion body 7:

[0056] S41. Preparation and soaking: Place the filter device into the container, pour rubber granules into the filter device, and then inject the interface agent into the container until the rubber granules are completely submerged. Soak for 30 minutes.

[0057] S42. Drying treatment: Take out the soaked rubber granules and place them in a sieve to dry until there is no obvious interface agent dripping from the surface of the granules.

[0058] S43. Mixing and stirring: Transfer the drained rubber granules to a mixing container, add A glue in a certain volume ratio, and stir thoroughly until uniformly mixed.

[0059] S44. Filling and Compacting: Slowly fill the gaps between the outer edge plate 2 of the tank bottom plate, the tank wall plate 3, and the high-density polyethylene plate 6 with the mixed rubber granules, compacting them with a scraper as you fill, until the compaction density is not less than 1.2 g / cm³. After filling, smooth the surface to form a slope that is higher on the inside and lower on the outside, with an angle of approximately 5-5.5°.

[0060] S45. Repeat the above steps until all gaps are filled, forming an elastic fusion body 7.

[0061] The elastic design of the bonding interface 4 between the elastic fusion body 7 and the heterogeneous material in this invention can adapt to the radial expansion and contraction and plastic warping of the tank edge plate 2, solving the defects of existing rigid materials being prone to cracking and flexible materials lacking resilience.

[0062] S5. Surface protection construction:

[0063] S51. External protection of high-density polyethylene sheet 6: After the elastic fusion body 7 has fully cured, apply B glue to the outer surface of the high-density polyethylene sheet 6 with a coating thickness of 3mm to ensure full coverage.

[0064] S52. Edge plate 2 slope protection: Apply B glue evenly to the slope outside the elastic fusion body (7) and the tank wall plate (3) at a certain height. The coating thickness is 3mm, the surface flatness error of the coating does not exceed 0.2mm, and ensure a smooth transition with the heterogeneous material bonding interface 4 of the tank wall to form a complete protective surface layer 8.

[0065] Through material system optimization, the protective lifespan can reach over 15 years in coastal high-salt spray environments, chemical zone acid and alkali media, and extreme temperature fluctuations, far exceeding traditional rigid materials (<3 years) and existing composite protection technologies (5-8 years). Simultaneously, the insulation properties of the surface protective layer and the elastic fusion body 7 reduce stray current interference, decreasing the cathodic protection potential fluctuation range by 60%. Furthermore, the integrated surface protective structure has no hidden leakage channels, allowing for early detection of potential problems through routine visual inspection, improving detection efficiency by 70%. For localized maintenance, the peelable and fused properties of the B-adhesive and high-density polyethylene board 6 reduce maintenance and cleaning time to 1 / 5 of traditional petrolatum-based materials, lowering maintenance costs by 60%.

[0066] The sealing technology for the outer edge of a single 100,000 m³ storage tank designed by the technical solution of this invention reduces the sealing and anti-corrosion construction cost by 30% compared with the existing CTPU system. Combined with a protection life of more than 15 years, the total life cycle cost is reduced by more than 55%. It significantly reduces the risk of corrosion and leakage of storage tanks, reduces material loss and environmental pollution, and can reduce the annual production stoppage loss due to corrosion by about RMB 200,000 per unit, while also reducing environmental risks such as heavy metal pollution.

[0067] 3. Effect Verification:

[0068] After the completion of this embodiment, an integrated sealed and corrosion-resistant structure was formed. Field testing showed that after 10 years of operation in a high-salt-spray coastal environment, the sealed and corrosion-resistant structure did not exhibit corrosion or leakage, and all performance indicators met design requirements, effectively ensuring the safe and stable operation of the storage tank.

[0069] It is worth noting that B-type adhesive can also use polyisocyanates and polyether polyols with high thixotropic index and excellent weather resistance. Polyisocyanates and polyether polyols have strong adhesion to various substrates such as cement and metal, high strength, and are water-resistant and corrosion-resistant. Polyurea has a fast curing speed, is not sensitive to humidity, has a dense coating, and has excellent elasticity and toughness.

[0070] It is worth noting that when the local sealing and anti-corrosion structure needs to be repaired, the part to be repaired can be cut off and new material can be added according to the preparation method of the sealing and anti-corrosion structure. The newly added sealing and anti-corrosion structure material can be fused and connected with the original sealing and anti-corrosion structure material without cracks. Compared with the phenomenon of removing all materials to prevent cracks in the sealing and anti-corrosion structure after repair in the existing technology, the sealing and anti-corrosion structure provided by this application saves the enterprise's production costs and has high repair efficiency.

[0071] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within the scope of its essence and protection. Such modifications or equivalent substitutions should also be considered to fall within the scope of protection of the present invention.

Claims

1. A sealing and corrosion-resistant structure for the outer edge plate of a storage tank, characterized in that, include: The sealing and isolation layer is made of high-density polyethylene board (6), which is fixed to the cement base (1) of the storage tank by board adhesive; The heterogeneous material bonding interface (4) is composed of A glue coated on the lower part of the tank wall plate (3); The elastic fusion body (7) fills the gap between the outer edge plate (2) of the tank bottom plate, the tank wall plate (3) and the high-density polyethylene plate (6). The elastic fusion body (7) is made of rubber particles soaked in an interface agent and dried and mixed with A glue. The surface protective layer is composed of B-type adhesive coated on the outer side of the high-density polyethylene plate (6), the outer edge slope of the elastic fusion body (7), and the tank wall plate (3) at a certain height.

2. The sealing and corrosion-resistant structure for the outer edge plate of the storage tank according to claim 1, characterized in that, The high-density polyethylene board (6) is 10 mm in size exposed at the edge of the cement base (1).

3. The sealing and corrosion-resistant structure for the outer edge plate of the storage tank according to claim 1, characterized in that, The heterogeneous material bonding interface (4) is coated on the lower part of the tank wall plate (3) within a range of 100mm-150mm from the tank edge plate (2) upwards, with a coating thickness of 1.5mm.

4. The sealing and corrosion-resistant structure for the outer edge plate of the storage tank according to claim 1, characterized in that, The density of the elastic fusion body (7) after filling and compaction is ≥1.2g / cm³, and the filling surface forms a slope that is higher inside and lower outside.

5. The sealing and corrosion-resistant structure for the outer edge plate of the storage tank according to claim 1, characterized in that, In the surface protective layer, the thickness of the B-type adhesive coated on the outer side of the high-density polyethylene plate (6), the outer edge slope of the elastic fusion body (7), and the tank wall plate (3) is 3 mm.

6. A construction method for a sealing and corrosion-resistant structure for the outer edge plate of a storage tank as described in any one of claims 1-5, characterized in that, Includes the following steps: S1. Base surface pretreatment: Clean the tank wall, exposed edge plate (2) and cement base (1) to remove loose rust, oil and dust; S2. Construction of sealing and isolation layer: Apply the adhesive of the board to the outer edge of the cement base (1) and the bonding surface of the high-density polyethylene board (6), let it stand until it is surface dry, and then paste the high-density polyethylene board (6) to the preset position of the cement base (1). S3. Construction of heterogeneous material bonding interface (4): Apply the A adhesive evenly within a predetermined height range at the bottom of the tank wall; S4. Preparation and filling of elastic fusion body (7): The rubber particles are soaked in the interface agent and then dried. The dried rubber particles are mixed with the A glue in proportion and stirred. The mixed rubber particles are filled into the gap between the outer edge plate (2) of the bottom plate of the storage tank, the wall plate (3) of the storage tank and the high-density polyethylene plate (6), and then compacted and smoothed. S5. Surface protection construction: Apply the B adhesive evenly to the outer side of the high-density polyethylene plate (6), the outer edge slope of the elastic fusion body (7), and the tank wall plate (3) at a certain height.

7. The construction method according to claim 6, characterized in that, In step S1, the pretreatment of the substrate adopts the lowest St2 or Sa1 level rust removal standard.

8. The construction method according to claim 6, characterized in that, In step S2, the adhesive for the board is allowed to stand until it is surface dry for 3-5 minutes.

9. The construction method according to claim 6, characterized in that, In step S41, the rubber particles have a particle size of 2-4 mm and are soaked in the interface agent for 30 minutes.

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