An integrated construction method for corrosion protection and cleaning of wastewater treatment plant pool walls

Abstract

This invention discloses an integrated construction method for corrosion protection and cleaning of wastewater treatment plant tank walls, belonging to the field of anti-corrosion coating construction technology for concrete structures. This method eliminates the need to empty the wastewater tank; the work can be carried out simply by lowering the water level by 1-2 meters, completing nine standardized construction procedures sequentially. This invention utilizes a composite protective system consisting of specialized repair mortar and multi-layer functional coatings, allowing construction even in high-humidity environments with a concrete substrate moisture content greater than 8%. The coating exhibits deep penetration, high bonding strength, resistance to acid and alkali corrosion, and resistance to silt erosion. Its ultra-low surface tension effectively inhibits sludge and moss adhesion, significantly reducing operation and maintenance costs. Samples showed no performance degradation after 90 days of continuous immersion in wastewater, and the overall protective service life can reach over 5 years. This method has a short construction cycle, minimal interference with normal wastewater treatment operations in the plant, and is suitable for the protection and renovation of various wastewater tank walls, including biological treatment tanks, sedimentation tanks, CASS tanks, and oxidation ditches.

Description

Technical Field

[0001] This invention relates to the field of anti-corrosion coating construction technology for concrete structures, and in particular to an integrated construction method for anti-corrosion and cleaning of sewage treatment plant pool walls. Background Technology

[0002] The walls of concrete structures such as biological treatment tanks, horizontal sedimentation tanks, CASS tanks, and oxidation ditches in sewage treatment plants are subjected to the most severe conditions, especially in the areas above and below the water level. These areas are in a constant state of alternating wet and dry conditions and are subjected to multiple destructive forces: the acidic and alkaline media in the sewage will cause chemical corrosion to the concrete, the flow of water containing silt will create continuous physical erosion, and the air bubbles generated by the aeration equipment will also bring impact loads. Under the superposition of multiple effects, the mortar on the surface of the concrete will gradually fall off, exposing the aggregate, and eventually causing the substrate to become uneven and the structure to break down.

[0003] At the same time, the rough and porous concrete surface after damage is extremely easy to absorb sludge and suspended impurities in sewage; the organic matter and silt in sewage provide a growth substrate for microorganisms such as moss and algae, which in turn leads to the large-scale growth and attachment of biofilm, forming stubborn pollution.

[0004] Currently, the industry mainly uses two methods to address this type of problem, both of which have significant drawbacks. The first is the traditional physical cleaning method, which relies on tools such as high-pressure water guns, wire brushes, and scrapers to regularly clean stains and biological attachments on the pool walls. This method not only requires a large amount of labor, has high maintenance costs, and involves high work intensity, but the hard tools will also continuously scratch and wear down the concrete surface, creating a vicious cycle of structural damage, contaminant adhesion, and further damage to the substrate through manual cleaning. It cannot solve the problem at its root. The second method is to apply ordinary anti-corrosion coatings. However, conventional epoxy and waterproof coatings on the market generally have performance shortcomings: First, they have strict requirements on the moisture content of the substrate. When the moisture content of the concrete exceeds 8%, the paint film is prone to blistering and peeling. The substrate needs to be dried for a long time before construction, resulting in a longer overall construction period. Second, the molecular weight of the coating resin is relatively large, making it difficult to penetrate into the concrete to seal the capillaries. It can only form a single layer of paint film on the surface, resulting in poor anti-corrosion durability. Third, the surface tension of the paint film is high, and its stain resistance is insufficient. After a short period of use, problems such as sludge adhesion and algae growth will reappear.

[0005] In addition, most existing anti-corrosion construction processes require the complete emptying of the sewage tank, forcing the sewage treatment system to shut down. This not only affects normal production in the plant area but also negatively impacts the stability and compliance of water quality standards. In summary, the industry currently lacks a complete solution that can be implemented under conditions of low water levels and high humidity, integrating structural repair, long-term corrosion protection, resistance to water erosion, prevention of biofouling, and easy surface cleaning. Therefore, developing an integrated anti-corrosion and cleaning construction method for sewage tank walls that is suitable for the harsh conditions of sewage tanks has extremely high engineering application value and practical significance. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies, such as easily damaged and heavily polluted wastewater tank walls, difficulty in cleaning, disruption of normal plant production caused by traditional construction methods, and poor overall performance of ordinary coatings. This invention provides an integrated construction method for corrosion protection and cleaning of wastewater treatment plant tank walls. This method eliminates the need to drain the tank water, can be applied under high-humidity substrate conditions, and utilizes a specialized composite coating system. It combines multiple functions, including structural repair, resistance to acid and alkali corrosion, resistance to silt erosion, prevention of sludge and moss adhesion, and easy cleaning. It offers a long protective lifespan and minimizes disruption to normal plant production during construction.

[0007] The technical solution adopted by this invention to achieve its purpose is: an integrated construction method for corrosion prevention and cleaning of sewage treatment plant pool walls, comprising nine sequentially executed construction steps, forming a complete process system of platform construction, base treatment, structural repair, and multi-layer composite coating. The specific solution is detailed below: Step S1, Setting up the work platform: Based on the real-time water level of the sewage tank, either a floating operating platform or a fixed steel pipe scaffold should be selected for erection: a floating operating platform should be used when the water body is not drained, and a fixed steel pipe scaffold should be erected in areas with low water levels. Both types of platforms must have a load-bearing capacity of not less than 3kN / m and an overturning stability of not less than 1.2. They can only be put into use after passing a special acceptance inspection upon completion.

[0008] Throughout the construction process, the water level in the sewage tank was lowered by only 1-2 meters without emptying the tank, ensuring the continuous operation of the sewage treatment equipment. Portable hazardous gas detectors were deployed in the construction area to monitor the concentrations of hydrogen sulfide and methane in real time. Temporary power supply on site implemented a three-level power distribution and two-level protection system, with a leakage current of 30mA, ensuring comprehensive construction safety management.

[0009] Step S2, Base Surface Treatment: High-pressure water guns are used in conjunction with manual tools to clean the pool wall surface, thoroughly removing surface sand, mud, moss, loose mortar, and the loose concrete layer inside, leaving only a solid and dense concrete base. After cleaning, no drying is required; the original high-humidity state is retained to provide a qualified construction base for subsequent processes.

[0010] Step S3, Interface Processing and Net Installation: Apply a water-based epoxy interface agent by roller or spray onto the treated substrate. By weight, the interface agent consists of: 58 parts water-based epoxy emulsion, 16 parts epoxy curing agent, 2.2 parts silicone wetting agent, 3.8 parts film-forming aid, 2 parts ethylene glycol butyl ether, 16 parts deionized water, 0.5 parts anti-mildew agent, and 1.5 parts pH adjuster.

[0011] After the interface agent has dried to the surface, wet-hang the alkali-resistant fiberglass mesh and fix it with a coupling agent. The construction requires the mesh to be flat, without stretching or wrinkles, and the mesh is used to improve the crack resistance of the base layer.

[0012] Step S4, Repair and leveling: A two-component, ultra-strong, fast-hardening, and tough repair mortar is used to level and smooth out pits and defects in the pool wall. This repair mortar consists of components A and B mixed in a weight ratio of 100:22. By weight, component A contains: 45 parts ordinary silicate cement, 32 parts 40-80 mesh quartz sand, 8 parts silica fume, 6 parts redispersible latex powder, 1.2 parts polypropylene short fiber, 1.5 parts water-reducing agent, 2.3 parts early-strength agent, 0.5 parts defoamer, and 3.5 parts alkali-resistant pigments and fillers. Component B contains: 12 parts water-based epoxy resin, 3 parts reactive diluent, 1.2 parts wetting agent, 0.8 parts antifreeze agent, and 5 parts deionized water.

[0013] The thickness of a single coat during construction is controlled to be 5mm, and the overall flatness deviation of the pool wall is 2mm. After the coat is applied, it is naturally cured for 24 hours. The material is cured by utilizing its fast hardening and early strength characteristics. This material can be applied normally in high humidity environments where the moisture content of the substrate is greater than 8%.

[0014] Step S5, Polishing and Hardening: On the repair and leveling layer surface, a polishing and hardening coupling agent is applied in two coats, with the total thickness of the two coats controlled to 1mm. This process is used to fill the fine pores in the base layer, further improving the density and surface hardness of the substrate.

[0015] Step S6: Application of small molecule penetrating sealing primer: The small molecule penetrating and sealing primer is applied in two coats. By weight, the primer consists of: 65 parts low molecular weight epoxy resin, 12 parts active penetrating resin, 8 parts composite alkali-resistant filler, 1.8 parts dispersant, 1.2 parts leveling agent, 0.8 parts defoamer, and 11.2 parts special diluent. The overall solid content of the primer is 80%.

[0016] The first coat is diluted with a higher ratio to ensure that the primer penetrates 5mm into the concrete substrate for deep sealing. The second coat is diluted with a lower ratio to form a continuous and dense sealing film on the surface. The two processes are carried out in sequence.

[0017] Step S7, Application of functional modified intermediate coating: An airless spraying process is used, with two coats of functional modified intermediate coating applied. By weight, the intermediate coating consists of: 52 parts modified epoxy resin, 18 parts mica iron oxide ash, 10 parts heavy calcium carbonate, 6 parts talc, 2.5 parts coupling agent, 3.5 parts impact modifier, 1.5 parts dispersant, 1 part leveling agent, and 5.5 parts composite solvent.

[0018] After the first coating is surface dry, the second coating is sprayed on. After the entire intermediate coating is fully dry, use 240-grit sandpaper to lightly sand and remove surface burrs. This coating, as the core anti-corrosion layer, has excellent acid and alkali resistance and impact resistance.

[0019] Step S8, Application of low-surface-weight, high-weather-resistance topcoat: The low-surface-tension, high-weather-resistance topcoat is diluted at a ratio of 5% to 10% and applied evenly using an airless sprayer. By weight, the topcoat consists of: 55 parts fluorocarbon-modified acrylic resin, 16 parts rutile titanium dioxide, 8 parts weather-resistant filler, 4.2 parts silicone low-surface-tension additive, 2.8 parts UV absorber, 1.5 parts antioxidant, 1 part leveling agent, 0.5 parts defoamer, and 11 parts composite solvent. Strict control during application is essential to prevent defects such as sagging, pinholes, and missed areas. The resulting paint film exhibits high gloss, high weather resistance, and resistance to oil and corrosion.

[0020] Step S9, Applying the easy-to-clean varnish: Dilute the easy-clean varnish at a ratio of 15% to 20% and apply it by air spraying or pump-press spraying. By weight, the varnish consists of: 60 parts of hydrophobic modified polyurethane resin, 7.5 parts of silicone hydrophobic additive, 4 parts of polytetrafluoroethylene micro powder, 3.2 parts of film-forming aid, 1.8 parts of wetting and leveling agent, 0.7 parts of defoamer, 0.8 parts of mildew inhibitor, and 22 parts of composite solvent.

[0021] After curing, the varnish has a static water contact angle of 90° and can withstand 10,000 washes. As the outermost functional surface layer, it achieves the effects of hydrophobicity, anti-adhesion, and easy cleaning.

[0022] This invention employs nine steps executed in strict sequence, using specialized materials and standardized construction techniques to sequentially complete the construction of a multi-layered protective system, including pool wall structure repair, interface enhancement, deep sealing, heavy-duty corrosion protection, weather resistance, and hydrophobic and easy-to-clean properties. Simultaneously, it incorporates comprehensive safety, environmental protection, and production assurance measures, resolving a series of issues such as pool wall corrosion, damage, sludge, and algae adhesion without affecting the normal operation of the wastewater treatment plant.

[0023] Compared with the prior art, the present invention has the following beneficial effects: 1. Minimal disruption to plant production: Construction only requires lowering the water level by 1-2 meters, without emptying the sewage tank. The sewage treatment system can operate normally throughout the entire process, with no production stoppage losses, making it suitable for the continuous operation of sewage treatment plants.

[0024] 2. Excellent adaptability to construction in high humidity environments: Repair mortar and water-based epoxy interface agent can be directly applied to concrete substrates with a moisture content greater than 8%, without the need for long-term drying of the substrate, effectively shortening the construction period for a single area and significantly improving construction efficiency.

[0025] 3. Excellent concrete structure repair effect: The two-component fast-hardening repair mortar has excellent compressive strength, flexural strength and bonding performance. With the synergistic effect of alkali-resistant fiberglass mesh, it can repair structural defects such as concrete spalling and pitting in the pool wall, restore the flatness and structural strength of the pool wall, and slow down further damage to the substrate.

[0026] 4. Corrosion and erosion resistant, long service life: The multi-layer gradient composite coating constructs a three-dimensional protection system. The small molecule penetrating and sealing primer deeply seals the capillary pores of concrete, while the functional intermediate coat and weather-resistant topcoat resist acid and alkali corrosion from sewage and erosion from mud and sand. The performance of the sample did not decrease after 90 days of continuous immersion in sewage, and the overall protection service life can reach more than 5 years.

[0027] 5. Significantly reduces post-maintenance pressure: The easy-to-clean varnish forms a hydrophobic protective interface, making it difficult for sludge and moss to adhere; daily maintenance only requires rinsing with water, eliminating the need for hard abrasive tools such as wire brushes, avoiding the problem of traditional cleaning methods exacerbating pool wall damage, and significantly reducing manual maintenance costs.

[0028] 6. Excellent construction safety and environmental protection: The entire construction process is equipped with harmful gas detection, three-level power distribution protection, and anti-drip coating collection measures, ensuring safe and controllable operation; coating materials and construction waste will not pollute sewage water bodies and the factory environment, meeting the environmental protection management requirements of municipal engineering. Attached Figure Description

[0029] Figure 1 This is a flowchart illustrating the integrated construction process for corrosion prevention and cleaning of wastewater treatment plant pool walls according to the present invention. Detailed Implementation

[0030] The present invention will now be described in detail with reference to specific embodiments, material ratios, and construction parameters.

[0031] This embodiment was applied to a wastewater treatment plant in China. The construction area covers mainstream tanks such as horizontal flow sedimentation tanks, anaerobic and aerobic zones of CASS tanks, and A2O process biological treatment tanks, and the working conditions are highly representative.

[0032] Construction foundation conditions Construction environment temperature: 15~30℃, ambient humidity: 60%~85%; measured moisture content of concrete pool wall base layer: 9%; sewage medium contains acidic and alkaline substances, suspended silt and microbial flora, which meets the conventional composition of municipal sewage; during construction, the overall water level of the pool drops by 1.5m, and the sewage treatment equipment in the plant area operates continuously throughout the process.

[0033] Example 1 like Figure 1 As shown, the construction method of this invention consists of nine sequential procedures. This embodiment uses the construction method of this invention and its supporting special materials, and strictly follows the nine procedures and quality standards. The specific steps are as follows: Step S1: Construction and Acceptance of the Work Platform Platforms are constructed differently for different pool conditions: For deep water areas such as horizontal sedimentation tanks and CASS tanks, custom floating operation platforms with specifications of 3000mm x 1500mm x 400mm are selected. The platforms float on the water surface and do not touch the bottom of the pool. For biological treatment pool areas with lower water levels, fixed scaffolding is constructed using 483.0mm national standard steel pipes. The scaffolding has a planar dimension of 2m x 2m, an erection height of 8m, and a longitudinal and transverse spacing of 1.0m between the uprights. The scaffolding is equipped with double scissor bracing and rigid wall ties, and the surface of the scaffolding is fully covered with steel mesh.

[0034] After the platform was erected, a designated person tested its load-bearing capacity and overturning stability. The measured load-bearing capacity was 3 kN / m, and the overturning stability was 1.2. After acceptance, a construction restricted area was demarcated, warning signs were posted, portable hazardous gas detectors were installed, and temporary power supply was completed.

[0035] Step S2: Surface Refinement A high-pressure water gun with a pressure of 8-12 MPa, combined with scrapers and wire cutters, is used for cleaning, focusing on areas prone to damage and adhesion above and below the water level. Floating sand, aged mortar, accumulated sludge, stubborn moss, and algae roots are thoroughly removed from the pool walls. Loose, sandy concrete layers are completely removed until the hard, dense concrete substrate is exposed. After cleaning, the surface must be free of loose particles, residual contaminants, and significant standing water; retain the original high humidity state without drying.

[0036] Step S3: Interface treatment and wet-hanging of alkali-resistant fiberglass mesh Apply the water-based epoxy interface agent evenly to the substrate using a roller coating method, ensuring uniform thickness, no missed areas, and no drips. Allow it to dry naturally at room temperature, with the drying time controlled between 30 and 60 minutes.

[0037] After the interface agent dries to the surface, wet hanging operation is carried out. The alkali-resistant fiberglass mesh is laid flat, with an overlap width of not less than 5cm. It is fixed by spot bonding with a special coupling agent. During the construction process, it is ensured that the mesh is free from bulging, stretching and wrinkling, and is tightly attached to the base surface to improve the overall crack resistance of the base layer.

[0038] Step S4: Repair and level with two-component repair mortar Mix the two-component super-strong fast-hardening tough repair mortar according to the weight ratio of component A: component B = 100:22, and stir with an electric mixer for 3 to 5 minutes until the mortar has a uniform color and no dry powder lumps.

[0039] Apply the coating using a scraper, with each coat controlling the thickness to 5mm. For areas with deeper defects, apply the coating in layers. Use a 2m straightedge for real-time monitoring to ensure the overall flatness of the pool wall is within 2mm. After coating, allow it to cure naturally for 24 hours. During this period, avoid touching or watering the surface; allow the material to harden naturally using its own properties.

[0040] Step S5: Polishing and Hardening Application The polishing and hardening coupling agent is applied in two coats. The first coat is a thin base coat, and the second coat is applied after the first coat is surface dry. The total thickness of the two coats is controlled to be 1mm. This process can fill the fine pores in the repair layer, improve the hardness and density of the substrate, and optimize the base surface for subsequent coating applications.

[0041] Step S6: Application of Small Molecule Penetrating Sealing Primer The small-molecule penetrating and sealing primer was applied in two coats using low-pressure air spraying equipment. The first coat involved a slightly higher dilution ratio to reduce the paint viscosity, ensuring the resin penetrated at least 5mm into the concrete substrate to fully seal capillaries. The second coat involved a lower dilution ratio to form a continuous and dense sealing film on the surface. The interval between the two coats was determined by the surface dryness of the first coat. Care was taken to prevent missed areas and pinholes. The measured solids content of this batch of primer was 80%, meeting design requirements.

[0042] Step S7: Application of Functionally Modified Intermediate Coating The modified intermediate coat is applied in two coats using airless spraying equipment. The second coat is applied only after the first coat is surface dry, ensuring uniform film thickness and full coverage. After both coats are completely dry, they are lightly sanded with 240-grit sandpaper to remove burrs, runs, and surface dust. Dust is then cleaned off. This coating is the core anti-corrosion layer, possessing excellent resistance to acids and alkalis, impact, and water erosion.

[0043] Step S8: Application of low-surface-area, high-weather-resistance topcoat Add a special thinner to the low-surface-area, high-weather-resistance topcoat at a ratio of 8%, stir well, and then spray at a uniform speed using an airless sprayer. Control the gun distance and travel speed during application to avoid defects such as runs, pinholes, and missed areas. The measured gloss of this paint film is 90%, and its weather resistance is 2000 hours, allowing it to withstand long-term exposure to sunlight and alternating wet and dry environments.

[0044] Step S9: Apply easy-clean varnish Add the special thinner to the easy-clean varnish at a ratio of 18%, stir well, and then apply it to the entire area using a pump-pressure spray method to ensure a smooth, continuous, and complete paint film interface. After the paint film has cured, the measured static water contact angle is 93°, and the scrub resistance is 11,200 cycles, with all indicators meeting the design requirements.

[0045] Safety and environmental protection management throughout the entire process Throughout the construction process, the water level in the pool was maintained at a 1.5m drop, and the wastewater treatment unit operated normally. The concentrations of harmful gases such as hydrogen sulfide and methane were tested every 30 minutes, and all results were within safe limits. Temporary on-site power supply strictly adhered to a three-level power distribution and two-level protection system. All power tools were equipped with leakage protection devices with a tripping current of 30mA. Material receiving trays and oil-absorbing cotton were laid under the work platform to catch dripping materials. Construction waste was collected and transported daily, and no water pollution issues occurred during the entire process.

[0046] Overall performance test results Mechanical properties: The measured compressive strength of the repair mortar is 33.2 MPa and the flexural strength is 7.6 MPa; the adhesion of the composite coating is Grade 1 and the impact strength is 50 kg / cm, all of which meet the standards.

[0047] Media resistance: The construction sample was immersed in the original sewage on site for 90 consecutive days. The coating did not show any chalking, loss of gloss, discoloration, blistering, cracking or peeling. The paint film was firmly bonded to the substrate and had good long-term stability.

[0048] Easy to clean and anti-adhesion performance: The coating has a static water contact angle of 93° and can withstand 11,200 washes; surface sludge can be completely removed by spraying with clean water or wiping with a mop. After 6 months of on-site use, no large-scale sludge or algae adhesion problems have appeared on the pool walls.

[0049] Structural stability: The flatness and integrity of the pool walls in the construction area remain good, and there are no cracks or peeling in the repair layer and coating layer.

[0050] Comparative Example 1 The walls of a biochemical treatment tank within the same factory area and under the same operating conditions were coated with traditional ordinary epoxy paint. This traditional process requires completely emptying the tank and allowing it to dry for at least three days, causing factory shutdowns. Post-use monitoring revealed: significant sludge buildup on the tank walls after one month; a large amount of algae growth along the waterline after three months; and loss of gloss and localized peeling of the paint film after six months. This area required manual cleaning every 15 days using a high-pressure water gun and wire brush, resulting in a large workload, high costs, and continuous damage to the concrete substrate from the hard tools, creating potential structural hazards.

[0051] The comparative results show that the present invention is significantly superior to existing traditional technologies in terms of ease of construction, production impact, protection life, and subsequent operation and maintenance.

[0052] Extended Applications of this Invention: This construction method and supporting material system can be applied not only to municipal sewage treatment plants, but also to various concrete water storage structures such as industrial wastewater treatment plants, chemical circulating water pools, and rainwater storage tanks. It can meet the needs of anti-corrosion, repair, and anti-fouling renovation under different water qualities and different corrosion conditions, and has a wide range of applications.

[0053] The above embodiments are only used to explain the present invention and are not intended to limit the protection of the present invention. Any non-substantial modifications made based on the essential solution of the present invention should fall within the protection scope of the present invention.

Claims

1. A sewage treatment plant pool wall corrosion and cleaning integrated construction method, characterized in that, Includes the following steps: S1. Erection of working platform: Select either a floating operating platform or a fixed steel pipe scaffolding platform according to the water level and working conditions in the pool. The platform should have a load-bearing capacity of 3kN / m and an overturning stability of 1.

2. It can be put into use only after passing the acceptance test. S2. Base surface treatment: Use a high-pressure water gun combined with manual tools to clean the pool wall, thoroughly remove surface sand, mud, moss, loose mortar and loose concrete, and retain a solid concrete base. S3. Interface treatment and mesh hanging: Apply water-based epoxy interface agent by roller or spray on the treated substrate. After the interface agent is surface dry, wet-hang alkali-resistant fiberglass mesh and fix it with coupling agent to ensure that the mesh is flat and wrinkle-free. S4. Repair and leveling: Use two-component ultra-strong fast-hardening tough repair mortar to scrape and level the pits and defects on the pool wall. The coating thickness is controlled at 5mm, and the overall flatness deviation of the pool wall is 2mm. Natural curing for 24 hours. S5. Polishing and hardening: Apply polishing and hardening coupling agent to the leveling layer surface in two coats, with a total thickness of 1mm for both coats, to improve the density and surface hardness of the base layer. S6. Small molecule penetrating sealing primer application: Apply small molecule penetrating sealing primer in two coats. For the first coat, increase the dilution ratio to ensure that the primer penetrates 5mm into the concrete substrate. For the second coat, reduce the dilution ratio to form a sealing film. S7. Functional Modification Intermediate Coating Application: The functional modification intermediate coating is applied in two coats using an airless spraying process. After the first coat is surface dry, the second coat is applied. After the intermediate coating is fully dry, the surface is lightly sanded with 240-grit sandpaper to remove burrs. S8. Application of low surface area high weather resistance topcoat: Control the paint dilution ratio to 5% to 10%, and use an airless sprayer to spray the low surface area high weather resistance topcoat evenly to avoid defects such as sagging, pinholes and missed coating. S9. Easy-clean varnish application: Control the paint dilution ratio to 15% to 20%, and apply the easy-clean varnish by air spraying or pump-pressed spraying to form the final protective top layer.

2. The sewage treatment plant pool wall corrosion and cleaning integrated construction method according to claim 1, characterized in that, The two-component ultra-strong, fast-hardening, and tough repair mortar described in step S4 is composed of component A and component B mixed in a weight ratio of 100:

22. By weight, component A comprises: 45 parts ordinary silicate cement, 32 parts 40-80 mesh quartz sand, 8 parts silica fume, 6 parts redispersible latex powder, 1.2 parts polypropylene short fiber, 1.5 parts water-reducing agent, 2.3 parts early strength agent, 0.5 parts defoamer, and 3.5 parts alkali-resistant pigments and fillers. Component B comprises: 12 parts of waterborne epoxy resin, 3 parts of reactive diluent, 1.2 parts of wetting agent, 0.8 parts of antifreeze agent, and 5 parts of deionized water.

3. The method according to claim 1, wherein the method is characterized by, The waterborne epoxy interface agent mentioned in step S3 comprises, by weight: 58 parts waterborne epoxy emulsion, 16 parts epoxy curing agent, 2.2 parts organosilicon wetting agent, 3.8 parts film-forming aid, 2 parts ethylene glycol butyl ether, 16 parts deionized water, 0.5 parts anti-mildew agent, and 1.5 parts pH adjuster.

4. The sewage treatment plant pool wall corrosion and cleaning integrated construction method according to claim 1, characterized in that, The small molecule penetrating and sealing primer mentioned in step S6 comprises, by weight: 65 parts of low molecular weight epoxy resin, 12 parts of active penetrating resin, 8 parts of composite alkali-resistant filler, 1.8 parts of dispersant, 1.2 parts of leveling agent, 0.8 parts of defoamer, and 11.2 parts of special diluent, with a primer solid content of 80%.

5. The sewage treatment plant pool wall corrosion and cleaning integrated construction method according to claim 1, characterized in that, The functional modified intermediate coating mentioned in step S7 includes, by weight: 52 parts modified epoxy resin, 18 parts mica iron oxide ash, 10 parts heavy calcium carbonate, 6 parts talc, 2.5 parts coupling agent, 3.5 parts impact modifier, 1.5 parts dispersant, 1 part leveling agent, and 5.5 parts composite solvent.

6. The sewage treatment plant pool wall corrosion and cleaning integrated construction method according to claim 1, characterized in that, The low surface area and high weather resistance topcoat described in step S8 comprises, by weight: 55 parts of fluorocarbon modified acrylic resin, 16 parts of rutile titanium dioxide, 8 parts of weather-resistant filler, 4.2 parts of organosilicon low surface tension additive, 2.8 parts of ultraviolet light absorber, 1.5 parts of antioxidant, 1 part of leveling agent, 0.5 parts of defoamer, and 11 parts of composite solvent.

7. The method according to claim 1, wherein the method is characterized by, The easy-clean varnish in step S9 comprises, by weight: 60 parts of hydrophobic modified polyurethane resin, 7.5 parts of silicone hydrophobic additive, 4 parts of polytetrafluoroethylene micro powder, 3.2 parts of film-forming aid, 1.8 parts of wetting and leveling agent, 0.7 parts of defoamer, 0.8 parts of mildew inhibitor, and 22 parts of composite solvent; the easy-clean varnish, after curing, has a static water contact angle of 90° and can withstand 10,000 washes.

8. The sewage treatment plant pool wall corrosion and cleaning integrated construction method according to claim 1, characterized in that: During construction, the water level in the sewage tank will only be lowered by 1-2m, without draining the tank. The construction area is equipped with a hazardous gas detector to monitor the concentration of hydrogen sulfide and methane gas in real time. Temporary power supply adopts three-level power distribution and two-level protection, with a leakage current of 30mA.

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