Preparation method of super-weather-resistant anticorrosive plug-in tank and application of super-weather-resistant anticorrosive plug-in tank in MBBR water treatment system

Abstract

The application relates to the sewage treatment field, in particular to a method for manufacturing an ultra-weather-resistant anticorrosive plug-connected tank and application of the tank in an MBBR water treatment system, which comprises a tank body, a connecting unit arranged on the tank body, and a flange bolt arranged on the tank body. The tank body module is standardized prefabricated in a factory, the tank body module is quickly positioned and spliced through cooperation of an insertion edge and an insertion groove, on-site assembling and sealing of the tank body at a splicing position can be realized through the flange bolt and a fastening nut, the construction period is greatly shortened, the tank can be quickly disassembled and reconstructed in a different place, utilization is improved, and through adoption of a double-layer functional design of an epoxy resin inner coating layer plus a polyester resin outer coating layer, the inner coating layer is dense and resistant to chemical corrosion, can resist acid and alkali, salt mist and erosion of various types of sewage for a long time; the outer coating layer is resistant to ultraviolet aging and powdering, and has a long outdoor service life.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment, and in particular to a method for manufacturing an ultra-weather-resistant and corrosion-resistant bolted tank and its application in an MBBR water treatment system. Background Technology

[0002] For a long time, the reactors, sedimentation tanks, and other structures in wastewater treatment plants have mainly adopted two forms: reinforced concrete structures and carbon steel welded structures. Although reinforced concrete structures are structurally stable, they have inherent disadvantages such as long construction periods (generally more than 3 months), large footprints, and difficulties in expansion and renovation. While carbon steel welded structures are faster to construct, they involve a large amount of on-site welding work, make it difficult to guarantee weld quality, easily damage the anti-corrosion layer, and once completed, they become a monolithic structure that is difficult to disassemble and relocate.

[0003] In recent years, prefabricated steel structure tanks have been widely used due to their advantages such as rapid construction, standardized production, and easy disassembly and relocation. Currently, prefabricated tanks on the market are mainly divided into two categories: enamel-lined assembled tanks and ordinary painted assembled tanks.

[0004] Enameled assembled tanks use high-temperature sintering to form an inorganic glassy coating, which has advantages such as high hardness and good corrosion resistance. However, they also have significant drawbacks: First, they are brittle and easily chip and crack under external impact, leading to pitting corrosion that spreads rapidly. Second, they cannot be repaired on-site and must be returned to the factory for re-firing, resulting in high repair costs and long repair cycles. Third, the sintering temperature is as high as 800-1000℃, resulting in high energy consumption and potential deformation of the steel plate. Fourth, they have poor weather resistance, with an outdoor service life of generally 10-15 years. In contrast, ordinary coated assembled tanks require on-site assembly for wastewater treatment. During construction, the edges must be aligned and fixed simultaneously, making the operation more difficult and prone to misalignment, thus affecting the overall sealing performance of the tank.

[0005] Therefore, developing a new type of prefabricated tank with excellent weather resistance, corrosion resistance, on-site repairability, and convenient construction, as well as its preparation method, has significant engineering application value. Summary of the Invention

[0006] This invention addresses the problems of brittleness, difficulty in repairing damage, high energy consumption, and poor weather resistance in existing enamel-coated assembled tanks, as well as the difficulties in assembling and poor sealing of ordinary coated assembled tanks.

[0007] The purpose of this invention is to provide a method for manufacturing an ultra-weather-resistant and corrosion-resistant bolted tank and its application in an MBBR water treatment system.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution: an ultra-weather-resistant and corrosion-resistant bolted tank, comprising a tank body, a connecting unit disposed on the tank body, and flange bolts disposed on the tank body; the tank body comprises multiple tank body modules, flanges disposed at the upper and lower ends of the outer wall of the tank body modules, a first connecting hole disposed on the flange for mating with the flange bolts, insertion edges disposed on both sides of the tank body modules, and a support block disposed on the inner wall of the tank body modules; the connecting unit comprises a support ring disposed on the tank body modules, an abutment protrusion disposed on the support ring for mating with the support block, a positioning component disposed on the support ring for mating with the insertion edge, and a second connecting hole disposed on the support ring corresponding to the first connecting hole.

[0009] As a preferred embodiment of the ultra-weather-resistant and corrosion-resistant bolted tank of the present invention, the positioning component includes multiple sets of fixed blocks disposed on the support ring, movable blocks disposed on the abutment protrusion, and a sealing element disposed between the fixed blocks and the movable blocks; the gap between the fixed blocks and the movable blocks is configured as an insertion groove.

[0010] As a preferred embodiment of the ultra-weather-resistant and corrosion-resistant bolted tank of the present invention, the sealing element includes multiple sets of fixing screws disposed on the movable block, fastening nuts that are threadedly engaged with the fixing screws, abutment plates disposed on the fixing screws, and abutment springs disposed on the abutment plates; the fixed block is provided with a movable cavity that mates with the abutment plates, and one end of the abutment spring abuts against the inner wall of the movable cavity.

[0011] Based on the above-mentioned ultra-weather-resistant and corrosion-resistant bolted tank, the present invention also provides a method for manufacturing an ultra-weather-resistant and corrosion-resistant bolted tank, comprising: S1: uncoiling and leveling a steel plate, and then laser-cutting or CNC-cutting holes to form a steel plate module; S2: shot-blasting the steel plate module obtained in step S1 to remove surface oxide scale and rust, obtaining a surface with cleanliness and roughness meeting the requirements; S3: rolling the surface-treated steel plate module into an arc-shaped tank body module with a predetermined curvature, and welding the connecting hole and the support block to the tank body module using tooling; S4: using an electrostatic spraying process, in step S3... The inner surface of the obtained arc-shaped tank body module is sprayed with epoxy resin powder, and the outer surface is sprayed with polyester resin powder to form a uniform powder coating; S5: The sprayed arc-shaped tank body module is sent into a curing oven for high-temperature curing, so that the powder coating melts, flows, cross-links and forms a film. After cooling, a corrosion-resistant tank body module is obtained; S6: The cured corrosion-resistant tank body module is inspected for appearance, film thickness and leakage current. After passing the inspection, it is packaged and shipped out; S7: The processed tank body modules are transported to the installation site. Adjacent tank body modules are connected by flange bolts. Sealing strips are set at the joints. The modules are assembled layer by layer to form a bolted tank body.

[0012] Based on the above-described method for manufacturing ultra-weather-resistant and corrosion-resistant bolted tanks, this invention also provides an application of ultra-weather-resistant and corrosion-resistant bolted tanks in MBBR water treatment systems, including the bolted tank being used as a bioreactor in the MBBR process, with the interior filled with MBBR suspended packing material for the biochemical treatment of wastewater.

[0013] As a preferred embodiment of the application of the ultra-weather-resistant and corrosion-resistant bolted tank of the present invention in an MBBR water treatment system, wherein: the MBBR suspended packing is a biological carrier made of polymer composite material, with a specific gravity slightly less than that of water, a surface with an uneven structure, and a specific surface area ≥ 500 m². 2 / m 3 .

[0014] As a preferred embodiment of the application of the ultra-weather-resistant and corrosion-resistant bolted tank of the present invention in the MBBR water treatment system, the bolted tank is equipped with a multi-layer water distribution device and an aeration device. Wastewater enters from the bottom of the tank and comes into full contact with the suspended packing to carry out a biochemical reaction, thereby removing COD, ammonia nitrogen and total nitrogen.

[0015] As a preferred embodiment of the application of the ultra-weather-resistant and corrosion-resistant bolted tank of the present invention in the MBBR water treatment system, the height of the bolted tank can be adjusted by increasing or decreasing the number of tank body modules according to the amount of water to be treated.

[0016] Beneficial effects: This invention utilizes standardized prefabrication of tank modules in the factory, enabling rapid positioning and assembly of the modules through the interlocking edges and slots. On-site assembly and sealing of the joints can be achieved solely with flange bolts and fastening nuts, significantly shortening the construction period. It also allows for rapid disassembly and relocation, improving utilization. The invention employs a dual-layer functional design with an epoxy resin inner coating and a polyester resin outer coating. The inner coating is dense and chemically resistant, enduring long-term resistance to acid, alkali, salt spray, and various types of wastewater. The outer coating is resistant to UV aging and chalking, ensuring a long service life outdoors. Using the tank as a bioreactor, the internal flow is uniform, the packing fluidization effect is excellent, and the treatment efficiency is high. The corrosion resistance ensures the stability of the reactor during long-term operation, making it particularly suitable for treating high-concentration, highly corrosive industrial wastewater and municipal sewage. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the overall structure of an ultra-weather-resistant and corrosion-resistant bolted tank.

[0019] Figure 2 This is a structural diagram of the tank body module of an ultra-weather-resistant and corrosion-resistant bolted tank.

[0020] Figure 3 This is a schematic diagram of the connection unit of an ultra-weather-resistant and corrosion-resistant bolted tank.

[0021] Figure 4 For ultra-weather-resistant and corrosion-resistant bolted tanks Figure 1 Enlarged view of the structure at point A in the middle.

[0022] Figure 5 This is a schematic diagram of the positioning components for an ultra-weather-resistant and corrosion-resistant bolted tank.

[0023] Figure 6 This is a cross-sectional structural diagram of the fixing block of an ultra-weather-resistant and corrosion-resistant bolted tank.

[0024] In the diagram: 1. Tank body; 11. Tank body module; 12. Flange; 13. Connection hole one; 14. Insertion edge; 15. Support block; 2. Connection unit; 21. Support ring; 22. Abutment protrusion; 23. Positioning component; 231. Fixing block; 2311. Insertion groove; 2312. Movable cavity; 232. Movable block; 233. Seal; 2331. Fixing screw; 2332. Fastening nut; 2333. Abutment piece; 2334. Abutment spring; 24. Connection hole two; 3. Flange bolt. Detailed Implementation

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0026] Example 1, referring to Figure 1 - Figure 6 This is the first embodiment of the present invention. This embodiment provides an ultra-weather-resistant and corrosion-resistant bolted tank, which includes: a tank body 1, a connecting unit 2 disposed on the tank body 1, and flange bolts 3 disposed on the tank body 1; wherein, the tank body 1 serves as the main body of the bolted tank, the connecting unit 2 is used to position and connect the modular components of the tank body 1, and the flange bolts 3 are used to cooperate with the connecting unit 2 to fix and connect the components of the tank body 1.

[0027] The tank body 1 includes multiple tank body modules 11, flanges 12 disposed at the upper and lower ends of the outer wall of the tank body modules 11, connection holes 13 disposed on the flanges 12 for mating with flange bolts 3, insertion edges 14 disposed on both sides of the tank body modules 11, and support blocks 15 disposed on the inner wall of the tank body modules 11. The tank body modules 11 are used to form the main body of the bolted tank, the flanges 12 are used to mate with the connecting unit 2 to realize the docking of adjacent tank body modules 11, the connection holes 13 are used to fix the docking edges of adjacent tank body modules 11 to the flange bolts 3, the insertion edges 14 are used to insert into the connecting unit 2 for positioning, and the support blocks 15 are used to support and abut against the connecting unit 2.

[0028] The connecting unit 2 includes a support ring 21 disposed on the tank body module 11, an abutment protrusion 22 disposed on the support ring 21 for cooperating with the support block 15, a positioning component 23 disposed on the support ring 21 for cooperating with the insertion edge 14, and a second connecting hole 24 disposed on the support ring 21 corresponding to the first connecting hole 13; wherein, the support ring 21 is used to connect and fix the upper and lower tank body modules 11 with the flange plate 12 through the action of the flange bolts 3, a sealing gasket is provided at the contact position between the support ring 21 and the flange plate 12, the abutment protrusion 22 is used to connect and fix the mating flange plate 12 with the first connecting hole 13 through the flange bolts 3, and the positioning component 23 is used to position and fix adjacent tank body modules 11 on the same layer for sealing.

[0029] The positioning component 23 includes multiple sets of fixed blocks 231 disposed on the support ring 21, movable blocks 232 disposed on the abutting protrusion 22, and a sealing element 233 disposed between the fixed blocks 231 and the movable blocks 232. The fixed blocks 231 are fixed on the support ring 21 and abut against the outer wall of the tank module 11, and the movable blocks 232 abut against the inner wall of the tank module 11. A sealing gasket is provided on the side of the fixed blocks 231 and the movable blocks 232 that abut against the tank module 11. The sealing element 233 is used to drive the fixed blocks 231 and the movable blocks 232 to clamp the connected side of the tank module 11 to achieve a seal.

[0030] The gap between the fixed block 231 and the movable block 232 is set as the insertion groove 2311. The insertion groove 2311 is used to cooperate with the insertion edge 14 to insert the tank body module 11, so that the adjacent tank body modules 11 on the same layer maintain the alignment of the docking, realize the positioning of the tank body module 11 on the support ring 21, and facilitate the installation and disassembly of the tank body module 11.

[0031] The sealing element 233 includes multiple sets of fixing screws 2331 set on the movable block 232, fastening nuts 2332 threadedly engaged with the fixing screws 2331, abutment pieces 2333 set on the fixing screws 2331, and abutment springs 2334 set on the abutment pieces 2333. The fixing screws 2331 are used to fix the movable block 232 and serve as a connection. The fastening nuts 2332 are used to rotate and drive the movable block 232 to move, thereby clamping and sealing the tank body module 11 with the fixing block 231. The abutment pieces 2333 are used to provide support for the movable block 232 with the abutment springs 2334, keeping the insertion slot 2311 open when it is to be inserted, so that the tank body module 11 can easily enter the insertion slot 2311.

[0032] The fixed block 231 is provided with a movable cavity 2312 that matches the abutment piece 2333. One end of the abutment spring 2334 abuts against the inner wall of the movable cavity 2312. The abutment spring 2334 is kept in a compressed state in the movable cavity 2312. The force generated drives the movable block 232 away from the fixed block 231, so that the insertion slot 2311 remains open.

[0033] In summary, firstly, the support ring 21 is fixedly installed on the base using flange bolts 3. Then, the tank body module 11 is positioned on the support ring 21 by the insertion edge 14 and the insertion groove 2311. At this time, the first connection hole 13 and the second connection hole 24 are aligned. Then, the flange bolts 3 are passed through the first connection hole 13 and the second connection hole 24. When all the tank body modules 11 of the first layer are inserted, the fastening nut 2332 is rotated to drive the fixed block 231 and the movable block 232 to clamp the insertion edge 14. The abutment protrusion 22 is used to clamp and seal the gap between the tank body module 11 and the connecting unit 2. Then, the flange bolts 3 are tightened to fix and seal the support ring 21 and the tank body module 11. At this time, the installation of the first layer of bolted tanks is completed. Then, the above process is repeated as required to erect the bolted tanks to the specified height.

[0034] Example 2, refer to Figure 1 - Figure 6 This is the second embodiment of the present invention. This embodiment provides a method for manufacturing an ultra-weather-resistant and corrosion-resistant bolted tank, which includes: S1: uncoiling and leveling a steel plate, and then laser cutting or CNC cutting holes to form a steel plate module. Laser cutting has high precision and a flat cut, which can ensure the hole alignment accuracy during subsequent assembly. S2: The steel plate module obtained in step S1 is shot blasted to remove surface oxide scale and rust, and to obtain a surface with cleanliness and roughness that meet the requirements. Shot blasting can significantly increase the contact area and mechanical interlocking force between the coating and the steel plate, and is a key process to ensure coating adhesion. The abrasive used in shot blasting is steel shot or steel wire cut shot. The surface cleanliness of the steel plate after shot blasting reaches Sa2.5 level, and the roughness reaches Rz 40-75μm. S3: The surface-treated steel plate module is rolled into a round shape to obtain an arc-shaped tank body module 11 with a predetermined curvature. The connecting hole 13 and the support block 15 are welded to the tank body module 11 by tooling. Rolling ensures the curvature accuracy of the steel plate and guarantees the roundness and sealing of the tank body during assembly. S4: Using electrostatic spraying process, epoxy resin powder is sprayed on the inner surface of the arc-shaped tank body module 11 obtained in step S3, and polyester resin powder is sprayed on the outer surface to form a uniform powder coating. Electrostatic spraying uses a high voltage electrostatic field to charge the powder and adsorb it onto the surface of the workpiece, which can achieve uniform coverage of dead corners such as grooves and welds. Among them, epoxy resin powder has high cross-linking density, strong adhesion, and chemical corrosion resistance, making it suitable for internal surfaces in contact with corrosive wastewater; polyester resin powder has a benzene ring structure in its molecular chain, which can effectively absorb ultraviolet light and has excellent weather resistance, making it suitable for external surfaces to resist outdoor environmental corrosion; epoxy resin powder is a thermosetting epoxy resin powder with a curing temperature of 180-200℃, a curing time of 18-20 min, and a coating thickness of 80-300 μm; polyester resin powder is a thermosetting polyester resin powder with a curing temperature of 180-200℃, a curing time of 18-20 min, and a coating thickness of 80-300 μm; the raw materials of epoxy resin powder include epoxy resin, curing agent, pigment, and filler, and the epoxy equivalent of epoxy resin is 700-900 g / eq; the raw materials of polyester resin powder include polyester resin, curing agent, pigment, and filler, and the acid value of polyester resin is 30-50 mg KOH / g; S5: The sprayed arc-shaped can body module 11 is sent into a curing oven for high-temperature curing, so that the powder coating melts, flows, cross-links, and forms a film. After cooling, the anti-corrosion can body module 11 is obtained. During the high-temperature curing process, the powder melts to form a continuous and dense coating, which forms a strong chemical bond and physical anchor with the substrate. The high-temperature curing adopts a segmented heating method. First, it is preheated at 120-150℃ for 5-8 minutes to allow the powder to initially melt and release the gas. Then, it is heated to 180-200℃ and held for 10-15 minutes to allow the coating to fully cross-link and cure. Finally, it is cooled to below 60℃ and discharged to avoid internal stress caused by rapid cooling. S6: The cured anti-corrosion tank body module 11 is inspected for appearance, film thickness and leakage. After passing the inspection, it is packaged and shipped. The leakage test is carried out using a high-voltage electric spark tester. The test voltage is set according to the coating thickness to ensure that the coating is free of pinholes and defects. S7: Transport the processed tank body module 11 to the installation site, connect adjacent tank body modules 11 with flange bolts 3, set sealing strips at the joints, and assemble layer by layer to form a bolted tank body. The sealing strip is made of EPDM rubber or butyl rubber, with compression set ≤25% and tensile strength ≥10MPa.

[0035] The rest of the structure is the same as in Example 1.

[0036] Example 3, referring to Figure 1 - Figure 6 This is the third embodiment of the present invention, which provides an application of an ultra-weather-resistant and corrosion-resistant bolted tank in an MBBR water treatment system, comprising: the bolted tank is used as a bioreactor in the MBBR process, and is filled with MBBR suspended packing material for the biochemical treatment of wastewater.

[0037] Among them, the MBBR suspended packing material is a biological carrier made of polymer composite material, with a specific gravity slightly less than that of water, an uneven surface structure, and a specific surface area ≥500m². 2 / m 3 The packing material is an AMC-type high-efficiency biological carrier, which is added to the reactor. The surface of the packing material is uneven, which is conducive to the attachment of microorganisms. It is also wear-resistant, anti-aging, and has a long service life.

[0038] The tethered tank is equipped with a multi-layer water distribution device and an aeration device. Wastewater enters from the bottom of the tank and comes into full contact with the suspended packing material to carry out a biochemical reaction, removing COD, ammonia nitrogen and total nitrogen. The wastewater enters the MBBR reactor after pretreatment, with the hydraulic retention time controlled at 6-8 hours. The aeration rate is adjusted according to the dissolved oxygen to maintain dissolved oxygen at 2-4 mg / L. Aeration keeps the packing material in a fluidized state, ensuring full contact between the biofilm and the wastewater.

[0039] The height of the bolted tank can be adjusted by increasing or decreasing the number of tank body modules 11 according to the amount of water to be treated.

[0040] The rest of the structure is the same as in Example 2.

[0041] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A super weather-resistant and corrosion-resistant bolted tank, characterized in that: Includes a tank body (1), a connecting unit (2) disposed on the tank body (1), and flange bolts (3) disposed on the tank body (1); The tank body (1) includes multiple tank body modules (11), flanges (12) disposed at the upper and lower ends of the outer wall of the tank body module (11), a connection hole (13) disposed on the flange (12) for mating with flange bolts (3), a plug-in edge (14) disposed on both sides of the tank body module (11), and a support block (15) disposed on the inner wall of the tank body module (11). The connecting unit (2) includes a support ring (21) disposed on the tank body module (11), an abutting protrusion (22) disposed on the support ring (21) for cooperating with the support block (15), a positioning component (23) disposed on the support ring (21) for cooperating with the insertion edge (14), and a connecting hole (24) disposed on the support ring (21) corresponding to the connecting hole one (13).

2. The ultra-weather-resistant and corrosion-resistant bolted tank as described in claim 1, characterized in that: The positioning component (23) includes multiple sets of fixed blocks (231) disposed on the support ring (21), movable blocks (232) disposed on the abutment protrusion (22), and a seal (233) disposed between the fixed blocks (231) and the movable blocks (232). The gap between the fixed block (231) and the movable block (232) is set as a plug groove (2311).

3. The ultra-weather-resistant and corrosion-resistant bolted tank as described in claim 2, characterized in that: The sealing element (233) includes multiple sets of fixing screws (2331) disposed on the movable block (232), fastening nuts (2332) threadedly engaged with the fixing screws (2331), abutment pieces (2333) disposed on the fixing screws (2331), and abutment springs (2334) disposed on the abutment pieces (2333). The fixed block (231) is provided with a movable cavity (2312) that matches the abutment piece (2333), and one end of the abutment spring (2334) abuts against the inner wall of the movable cavity (2312).

4. A method for manufacturing an ultra-weather-resistant and corrosion-resistant bolted tank, based on the ultra-weather-resistant and corrosion-resistant bolted tank of claim 3, characterized in that, Includes the following steps: S1: Uncoil and level the steel plate, then perform laser cutting or CNC hole cutting to form steel plate modules; S2: The steel plate module obtained in step S1 is shot blasted to remove surface oxide scale and rust, and to obtain a surface with cleanliness and roughness that meet the requirements. S3: The surface-treated steel plate module is rolled into a round shape to obtain an arc-shaped tank body module (11) with a predetermined curvature, and the connecting hole (13) and the support block (15) are welded to the tank body module (11) by tooling; S4: Using electrostatic spraying process, epoxy resin powder is sprayed on the inner surface of the arc-shaped tank body module (11) obtained in step S3, and polyester resin powder is sprayed on the outer surface to form a uniform powder coating. S5: The sprayed arc-shaped tank body module (11) is sent into the curing oven for high-temperature curing, so that the powder coating melts, flows, cross-links and forms a film, and after cooling, the anti-corrosion tank body module (11) is obtained. S6: The appearance, film thickness and leakage of the cured anti-corrosion tank body module (11) are tested. After passing the inspection, it is packaged and shipped out. S7: Transport the processed tank body module (11) to the installation site, connect the adjacent tank body modules (11) with flange bolts (3), set sealing strips at the joints, and assemble layer by layer to form a bolted tank body.

5. An application of an ultra-weather-resistant and corrosion-resistant bolted tank in an MBBR water treatment system, based on the manufacturing method of the ultra-weather-resistant and corrosion-resistant bolted tank as described in claim 4, characterized in that: The bolted tank is used as a bioreactor in the MBBR process, and is filled with MBBR suspended packing material for the biochemical treatment of wastewater.

6. The application of the ultra-weather-resistant and corrosion-resistant bolted tank as described in claim 5 in the MBBR water treatment system, characterized in that: The MBBR suspension packing material is a biological carrier made of polymer composite material, with a specific gravity slightly less than water, a surface with an uneven structure, and a specific surface area ≥500m². 2 / m 3 .

7. The application of the ultra-weather-resistant and corrosion-resistant bolted tank as described in claim 6 in the MBBR water treatment system, characterized in that: The bolted tank is equipped with a multi-layer water distribution device and an aeration device. Wastewater enters from the bottom of the tank and comes into full contact with the suspended packing to carry out a biochemical reaction, removing COD, ammonia nitrogen and total nitrogen.

8. The application of the ultra-weather-resistant and corrosion-resistant bolted tank as described in claim 7 in the MBBR water treatment system, characterized in that: The height of the bolted tank can be adjusted by increasing or decreasing the number of layers of the tank body module (11) according to the amount of water to be processed.

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