An atmospheric dust removal device for subway tunnel construction

Abstract

The application discloses a large air dust removal device for subway tunnel construction and belongs to the technical field of tunnel safety devices, in particular relates to a dust fall and removal device during subway tunnel construction. The device comprises a base and a water curtain mechanism, further comprises a rotary lifting mechanism, the water curtain mechanism is rotatably arranged on the base through the rotary lifting mechanism, a water curtain recovery mechanism, a sewage filtering mechanism and a sewage purification mechanism are arranged on the base, the water curtain recovery mechanism recovers the water curtain, is used for filtering of the sewage filtering mechanism and purification of the sewage purification mechanism, and the purified water reenters the water curtain mechanism. The device forms a water curtain by directly spraying water, improves the dust capture efficiency in the air, is provided with a recovery device, can recover part of the sprayed water for secondary use, reduces the waste of water source, and can also control and reduce the tunnel haze concentration.

Description

Technical Field

[0001] This invention relates to the field of tunnel safety device technology, and in particular to dust suppression and removal devices during subway tunnel construction. Background Technology

[0002] Existing technologies generally use tunnel boring machines (TBMs) for subway tunnel excavation. During the excavation process, the soil accumulated at the rear is excavated again by the excavator and transported to the outside space by transport vehicles. The above process generates a large amount of dust. Since the tunnel is a closed space, the large amount of dust released into the atmosphere of the subway tunnel is difficult to disperse effectively, which poses a serious safety hazard to the health of subway construction workers.

[0003] Existing dust suppression devices include installing spray nozzles on the side walls or enclosures of subway tunnels to capture dust using water mist. However, as the tunnel boring machine (TBM) continues to advance, new spray nozzles need to be installed behind the TBM continuously, resulting in a large workload. Additionally, fog cannons are also used for dust suppression. However, both fog cannons and spray nozzles share a common problem: the water mist is sprayed directly into the tunnel space, which over time increases the humidity inside the tunnel. In enclosed spaces, this can lead to smog, reducing visibility, causing water damage to construction equipment, and making the construction site slippery, potentially causing safety accidents. Furthermore, the water cannot be recycled, resulting in significant water waste, and the timeliness of spray dust suppression is not high. Summary of the Invention

[0004] The purpose of this invention is to provide an atmospheric dust suppression device for subway tunnel construction. This device forms a water curtain by directly spraying water, improving the efficiency of dust capture in the atmosphere. It also includes a recycling device to recover and reuse some of the sprayed water, reducing water waste. Furthermore, the water curtain, combined with anti-splash measures, prevents the rapid formation of smog in the atmosphere, unlike spraying. The device can switch between water spraying and mist recovery, solving the problems of smog reducing visibility inside the tunnel and easily causing water damage to construction equipment. Additionally, the device can adjust the height and direction of the water curtain as needed to improve the dust suppression effect. The specific solution is as follows:

[0005] An atmospheric dust removal device for subway tunnel construction includes a base and a water curtain mechanism, and also includes a rotating lifting mechanism. The water curtain mechanism is rotatably and liftably mounted on the base via the rotating lifting mechanism. The base is equipped with a water curtain recycling mechanism, a sewage filtration mechanism, and a sewage purification mechanism. The water curtain recycling mechanism recycles the water curtain for filtration by the sewage filtration mechanism and purification by the sewage purification mechanism. The purified water re-enters the water curtain mechanism.

[0006] The water curtain mechanism includes components with a vertical cross-section in the shape of "". The nozzle is shaped like a square cross-section, a pumping device and a first water pipe. The bottom of the nozzle is equipped with a base. Multiple nozzles are opened on one side wall of the nozzle facing the base. The nozzles are venturi-shaped. The multiple nozzles spray water toward the water curtain recovery mechanism to form a water curtain. The nozzle is connected to the pumping device through the first water pipe.

[0007] The water curtain recovery mechanism includes water holes on the base, through which the water curtain flows to the wastewater filtration mechanism, which includes a filter screen installed inside the base.

[0008] Furthermore, the rotary lifting mechanism includes a dual-axis motor, a rotating disk, and a screw. An annular hole is provided on the end wall of the base facing the nozzle, and the end wall portion within the annular hole constitutes the rotating disk. An electromagnetic clutch assembly 1 and an electromagnetic clutch assembly 2 are provided on the motor shaft 1 of the dual-axis motor. An electromagnetic clutch assembly 1 is provided with a drive gear 1, which is connected to driven gears 1 located on both sides of it via a transmission belt 1. A screw 1 is provided on the driven gear 1, which passes through the rotating disk. The nozzle is vertically mounted on the screw 1. The electromagnetic clutch assembly 2 is located at the central shaft hole of the rotating disk. An electromagnetic clutch assembly 3 is provided on the motor shaft 2 of the dual-axis motor, and the electromagnetic clutch assembly 3 is located at the central shaft hole of the circular filter screen.

[0009] Furthermore, after the motor shaft passes through the filter screen, an electromagnetic clutch assembly four is installed on it. The electromagnetic clutch assembly four is equipped with a driving gear two, which is connected to driven gear two located on both sides of it via a transmission belt two. A screw two is installed on the driven gear two, which passes through the sewage purification mechanism and is installed on the base. A screw block is installed on the screw two, which is located between the screw two and the purification layer.

[0010] Furthermore, it also includes a smog extraction mechanism, which includes an air pump with dual air inlets controlled by an electromagnetic valve, an air inlet pipe, an air passage one, an air passage two, and an air outlet pipe. One air inlet of the air pump is connected to one end of the air inlet pipe, and the other end of the air inlet pipe is connected to a nozzle. The other air inlet of the air pump is connected to the air passage. Air passage one and air passage two are respectively installed through the side wall of the base. Air passage one is located between the filter screen and the rotating disk, and air passage two is located at the side wall of the base. The air outlet of the air pump is connected to one end of the air outlet pipe, and the air outlet pipe is connected to the water accumulation part of the base through air passage two.

[0011] Furthermore, the pumping device includes an electrically controlled dual-outlet water pump, the other outlet of which is connected to a second water pipe, the outlet of which is located between the sewage filtration mechanism and the sewage purification mechanism.

[0012] Furthermore, after the air outlet pipe passes through the second air passage, its air outlet is fixedly installed on the sewage purification mechanism and located between the sewage filtration mechanism and the sewage purification mechanism.

[0013] Furthermore, the rotating disk is provided with a splash-proof layer, and a water supply pipe is connected to the side wall corresponding to the water accumulation part of the base. Rollers are provided at the bottom of the device, and push handles are provided on the side wall of the device. The base is a hollow cylindrical shape, and the edge of its upper end face protrudes to form an annular flange to block splashing water. The shaped nozzle is arranged radially along the rotating disk.

[0014] Furthermore, the wastewater purification mechanism includes a layered purification layer set in the base below the filter screen. The purification layer includes a coarse filtration interception layer that intercepts silt particles and fibrous impurities of not less than 20μm, a magnetic flocculation layer that adsorbs ferromagnetic particles and enhances colloidal coagulation, an ultrafine filtration layer that traps fine dust and colloids of 1-20μm, an antibacterial disinfection layer, an oil adsorption, odor removal and partial heavy metal adsorption purification layer, and a slow-release scale inhibition layer that prevents calcium and magnesium ion scaling.

[0015] Furthermore, multiple venturi-shaped nozzles are also provided on other side walls of the nozzle, and each nozzle is equipped with a solenoid valve. The solenoid valve, pumping device, air pump, electromagnetic clutch assembly, and dual-axis motor are all connected to a PLC.

[0016] Furthermore, the device also includes a dust concentration sensor, a haze particle sensor, a nozzle water accumulation sensor, and a water level sensor 1 and a water level sensor 2 set at different heights in the water accumulation section, and each is connected to a PLC. The dust concentration sensor detects the dust concentration in the tunnel atmosphere in real time, the haze particle sensor detects the haze particle concentration in real time, and the nozzle water accumulation sensor detects the presence or absence of water accumulation in the nozzle in real time.

[0017] Compared with the prior art, the present invention has at least one of the following technical effects:

[0018] 1. The device of the present invention forms a water curtain by directly spraying water, which improves the capture efficiency of dust in the atmosphere. At the same time, it is equipped with a recycling device that can recycle some of the sprayed water for reuse, reducing water waste and mitigating the hazards of slippery conditions caused by water accumulation in the tunnel. In addition, the water curtain, combined with anti-splash measures, does not cause the rapid formation of smog in the atmosphere like spraying. The device can switch between spraying water and mist recycling, which can solve the problem of smog in the background reducing visibility in the tunnel and easily causing water stains to damage construction equipment.

[0019] 2. The device of the present invention adjusts the height and direction of the water curtain rotation according to the dust distribution and flow direction, and controls the number and mode of opening the nozzles as needed, which is flexible and improves the dust removal effect, and the water curtain dust removal is more efficient.

[0020] 3. The spray nozzle and base of this invention can be used to create negative pressure to extract smog. One device can simultaneously achieve the functions of spraying water curtain and extracting smog, reducing the number of devices in the tunnel.

[0021] 4. Based on the data detection results, the present invention designs a backwashing purification layer structure, which can realize purification while backwashing. If the wastewater detection data exceeds a predetermined threshold, the purification effect can be improved by backwashing when the purification layer has not reached the point where it needs to be disassembled for maintenance.

[0022] 5. The present invention designs a structure in which the second water pipe is controlled by PLC to pump the accumulated water into the space between the filter screen and the purification layer. It can repeat the purification in real time based on the data detection results of the water accumulation section, thereby improving the purification effect.

[0023] 6. The smog extracted by this invention can be recycled into the water collection section for secondary use, and the gas is discharged after being purified by the purification layer, which can improve the air quality in the tunnel.

[0024] 7. Through structural design, this invention can effectively recycle the extracted smog;

[0025] 8. The filter screen of this invention can rotate, effectively preventing the mesh from clogging;

[0026] 9. The purification layer of the present invention can filter mud and sand particles, fiber impurities, fine dust and colloids. It can also adsorb ferromagnetic particles and enhance colloidal coagulation, antibacterial disinfection, adsorb oil stains, remove odors, and release scale inhibitors to prevent metal ions from scaling on metal spray nozzles. It fully considers the multiple purification factors of subway dust, with comprehensive functions and synergistic effects to improve the purification effect.

[0027] 10. Set a disc-shaped rotating disk, and set " " along the radial direction of the rotating disk. The water sprayed from the shaped nozzle has a larger recovery area, and the two rotate synchronously, working in conjunction with the annular flange to ensure that the rotating disk rotates to every angle. The water sprayed from the nozzle can be effectively recycled. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a front sectional view of the atmospheric dust removal device for subway tunnel construction in this application, viewed radially along the rotating disk;

[0030] Figure 2 This is a side view of the atmospheric dust removal device for subway tunnel construction in this application;

[0031] Figure 3 This is a top view of the atmospheric dust removal device for subway tunnel construction in this application;

[0032] Figure 4 This is a schematic diagram of the stacked structure of the purification layer in this application;

[0033] Figure 5 This is a connection diagram of the automatic control system of this application. Attached Figure Description

[0035] 1-Base; 2-Spray nozzle; 3-First water pipe; 4-Nozzle; 5-Water hole; 6-Annular flange; 7-Filter screen; 8-Dual-axis motor; 9-Rotating disk; 10-Annular hole; 11-Motor shaft one; 12-Electromagnetic clutch assembly one; 13-Electromagnetic clutch assembly two; 14-Drive gear one; 15-Transmission belt one; 16-Driven gear one; 17-Screw one; 18-Motor shaft two; 19-Electromagnetic clutch assembly three; 20-PLC; 21-Electromagnetic clutch assembly four; 22-Drive gear two; 23-Transmission belt two; 24-Driven gear two; 25-Screw two; 26-Purification layer; 27-Screw block; 28-Splashproof layer; 29-Water supply pipe; 30-Pumping device; 31-Second water pipe; 32-Air pump; 33-Air inlet pipe; 34-Airway 1; 35-Airway 2; 36-Outlet pipe; 37-Dust concentration sensor; 38-Haze particle sensor; 39-Water accumulation sensor; 40-Laser particle size sensor; 41-Laser turbidimeter 1; 42-Differential pressure sensor group; 43-Magnetic particle counter group; 44-Electromagnetic pulse generator; 45-Zeta potentiometer; 46-TOC sensor; 47-Fluorescent biosensor; 48-Conductivity sensor; 49-Laser turbidimeter 2; 50-Residual chlorine sensor; 51-Water level sensor 1; 52-Water level sensor 2; 53-Coarse filter interception layer; 54-Magnetic flocculation layer; 55-Ultrafine filter layer; 56-Antibacterial disinfection layer; 57-Adsorption purification layer; 58-Slow-release scale inhibition layer; 59-Roller; 60-Solenoid valve. Detailed Implementation

[0036] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0037] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0038] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0039] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0040] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0041] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0042] This invention discloses an atmospheric dust removal device for subway tunnel construction, see attached document. Figure 1-5The device includes a base 1 and a water curtain mechanism, as well as a rotating lifting mechanism. The water curtain mechanism is rotatably and vertically mounted on the base 1 via the rotating lifting mechanism. The base 1 is equipped with a water curtain recycling mechanism, a sewage filtration mechanism, and a sewage purification mechanism. The water curtain recycling mechanism collects the water curtain for filtration by the sewage filtration mechanism and purification by the sewage purification mechanism. The purified water then re-enters the water curtain mechanism. This invention forms a water curtain through the water curtain mechanism to achieve a dust suppression effect. The water curtain recycling mechanism recovers the water curtain, alleviating the problems of existing technologies where water spraying or misting cannot be recycled, leading to slippery and difficult-to-manage water accumulation in subway tunnels, smog formation, and water waste over time. Furthermore, the purified water re-enters the water curtain mechanism to reform the water curtain for reuse. The water curtain mechanism uses the rotating lifting mechanism to raise or lower the water curtain, or rotate the water curtain vertically towards the direction of dust movement, to achieve a better dust suppression effect. The device is equipped with rollers 59 at the bottom and push handles on the side walls, allowing it to be manually pushed to areas with high dust levels in the tunnel, or a power source can be added for operation.

[0043] Specifically, the water curtain mechanism includes components with a vertical cross-section in the shape of a " The system consists of a square-shaped nozzle 2, a pumping device 30, and a first water pipe 3. A base 1 is located at the bottom of the nozzle 2. Multiple nozzles 4, shaped like venturi tubes, are located on one side wall of the nozzle 2 facing the base 1. These nozzles spray water towards a water curtain recovery mechanism, forming a water curtain. The nozzle 2 is connected to the pumping device 30 via the first water pipe 3. The pumping device 30 is used to pump the water recovered from the base 1 back into the nozzle 2 for secondary use. The "shape" structural design causes the nozzle 2 to face one side wall of the base 1 (" The nozzles 4 (with a horizontal sidewall of a "-shaped" structure, parallel to the upper surface of the base 1) allow water to flow vertically downwards onto the base 1, forming a vertical water curtain. The spacing between adjacent nozzles 4 is reasonable, and the sprayed water overlaps to form the water curtain. (See attached diagram.) Figure 1-2 The cross-section is square, which facilitates the arrangement of multiple rows of nozzles 4 side by side on the side wall facing the base 1. Each row of nozzles 4 can be arranged relatively parallel or staggered, so that the vertical water curtain forms a gap that dust cannot penetrate. At the same time, nozzles 4 can also be opened on the side of the side wall facing away from the base 1, which can effectively capture the dust above the nozzle 2. Nozzles 4 are also provided on the two vertical sidewalls of the "shaped" nozzle 2, and can be provided on both the inner and outer sides. The two inner nozzles 4 spray water curtains that overlap perpendicularly with the horizontal sidewalls, improving the dust removal effect. The water curtains fall onto the water curtain recovery mechanism and can be effectively recovered. The water curtains sprayed by the outer nozzles 4 are used to remove dust. The dust in the tunnels on both sides of the "shaped" structure is removed. All nozzles 4 are venturi tubes to increase the water jet rate. All nozzles 4 are equipped with solenoid valves 60, which are connected to PLC 20. They can selectively open all or some nozzles 4 according to the dust distribution, for example, giving priority to opening recyclable nozzles 4.

[0044] See appendix Figure 1 and attached Figure 3 The water curtain recycling mechanism includes water holes 5 opened on the base 1. The base 1 is a hollow cylindrical shape. The water holes 5 are set through the upper wall of the base 1. The edge of the upper surface of the water hole 5 is raised to form an annular flange 6, which is used to block splashing water. Water flows into the sewage filtration mechanism inside the base 1 through the water holes 5. The sewage filtration mechanism includes a circular filter screen 7 set in the base 1, which plays the role of filtering large particles. The water passing through the filter screen 7 flows to the sewage purification mechanism below it.

[0045] The wastewater purification mechanism includes a layered purification layer 26, located within the base 1 below the filter screen 7. The purification layer 26 includes a coarse filtration layer 53 that intercepts silt particles and fibrous impurities no smaller than 20μm; a magnetic flocculation layer 54 that adsorbs ferromagnetic particles and enhances colloidal coagulation; an ultrafine filtration layer 55 that traps fine dust and colloids of 1-20μm; an antibacterial and disinfection layer 56; a purification layer 57 that adsorbs oil, removes odors, and partially adsorbs heavy metals; and a slow-release scale inhibitor layer 58 that releases scale inhibitors and prevents calcium and magnesium ion scaling. Each of these functional layers is disc-shaped and can be integrated into a single structure through vertical contact. The layers are separated by a stainless steel support plate with perforations. The plate is 5mm thick and has a 10mm diameter. The edges are sealed with smooth plastic sealing rings to the inner wall of the base 1 to prevent wastewater from bypassing the flow. The sealing rings can slide up and down along the base 1, or the layers can be spaced apart vertically. If spaced apart, each layer can be reinforced with porous stainless steel or similar materials.

[0046] The coarse filter interception layer 53 is preferably 60mm thick and includes honeycomb polyurethane foam with a pore size preferably of 20-50μm. The foam surface is coated with a polytetrafluoroethylene coating that is anti-adhesive and easy to backflush. The magnetic flocculation layer 54 includes a permanent magnet grid composed of neodymium iron boron magnets with a thickness of 40mm. The rod-shaped neodymium iron boron magnets are arranged in parallel to form the grid. The distance between adjacent neodymium iron boron magnets in the same column and between adjacent columns of neodymium iron boron magnets is 5mm. The spaces between the neodymium iron boron magnets are filled with magnetic ceramic particles with a particle size of 3-5mm. This layer mainly adsorbs ferromagnetic impurities that may be contained in construction dust (such as iron powder from tunnel boring machine wear) and abrasion debris from underground metal debris. The ultrafine filter layer 55 has a preferred thickness of 50 mm and includes a gradient pore size glass fiber membrane. The upper pore size is preferably 10-20 μm, and the lower pore size is preferably 1-10 μm. The membrane substrate is impregnated with nano-ZnO, which has antibacterial properties, prevents biological slime from clogging, and traps fine dust and colloids of 1-20 μm. The antibacterial disinfection layer 56 is 50mm thick and consists of three layers: the upper layer comprises a porous ceramic plate loaded with silver ions (5μm pore size, 0.1% silver ion content); the middle layer comprises an ultraviolet photocatalytic mesh, which includes a titanium mesh loaded with TiO2 and a low-pressure ultraviolet lamp mounted on it; and the lower layer is a slow-release chlorine tablet carrier, comprising a polyvinyl chloride (PVC) mesh plate with a chlorine-containing disinfectant tablet embedded within it. The chlorine-containing disinfectant tablet dissolves and releases 0.5 grams of effective chlorine per hour in water. Silver ions disrupt bacterial cell membranes, providing long-lasting antibacterial effects. Ultraviolet light (wavelength 254nm) combined with TiO2 photocatalysis oxidizes and inactivates bacteria and viruses. The slow-release chlorine tablet releases a low concentration of hypochlorous acid, enhancing disinfection. This triple synergistic antibacterial approach of "metal ions + photocatalysis + chemical slow release" solves the problems of "incomplete antibacterial action and short duration" associated with single-method approaches. The adsorption and purification layer 57 is 30mm thick and includes mesoporous activated carbon and bamboo fiber composite felt, arranged in layers. The bamboo fiber composite felt has a porosity of 85%, adsorbing oil, removing odors and some heavy metals. The natural hydrophilicity of bamboo fiber increases water flow. The activated carbon is loaded with nano-MnO2, which can oxidize and decompose some organic oil. The slow-release scale inhibitor layer 58 is 20mm thick and includes porous calcium carbonate ceramic particles loaded with phosphonates, with a particle size of 2-3mm. It releases scale inhibitors to prevent calcium and magnesium ions from forming scale. The slow-release phosphonates are encapsulated in the pores of the ceramic particles, continuously inhibiting the formation of scale in the circulating water and protecting the nozzle 4.

[0047] After the water curtain captures dust, the wastewater is first pre-filtered by the upper filter screen 7 before entering this filtration layer, achieving a graded purification mechanism: the coarse filtration interception layer 53 uses a three-dimensional network structure of honeycomb foam to physically intercept silt particles and construction fibers, while the polytetrafluoroethylene coating reduces particle adhesion and facilitates backwashing regeneration; the magnetic flocculation layer 54 utilizes the magnetic field generated by permanent magnets to adsorb ferromagnetic particles (such as iron powder generated by tunnel boring machine wear) in the wastewater onto magnetic ceramic particles, while the magnetic field promotes the aggregation of colloidal particles (such as clay particles) into larger particles, improving the subsequent filtration efficiency. The ultra-fine filtration layer 55 features a gradient glass fiber membrane with an "upper layer for coarse filtration and lower layer for fine filtration" design, avoiding rapid clogging of single-pore membranes. Nano-ZnO components inhibit bacterial growth (construction wastewater is prone to microbial growth). The antibacterial disinfection layer 56 employs a triple synergistic antibacterial principle: the first layer uses metal ions for long-lasting antibacterial action; the upper layer of the antibacterial disinfection layer 56 uses a silver ion ceramic plate to continuously release Ag⁺ (concentration 0.05-0.1 mg / L) through ion exchange. Ag⁺ penetrates the bacterial cell membrane, binds to DNA, and inhibits its replication, thus effectively preventing bacterial growth. The 24-hour inhibition rate against Enterobacteriaceae and molds is ≥99%, and the silver ions exhibit high stability, allowing for sustained release for over 3 months. The second layer of ultraviolet photocatalytic inactivation utilizes a middle-layer ultraviolet lamp (10-15W) emitting 254nm ultraviolet light to directly destroy the nucleic acid structure of bacteria and viruses. Simultaneously, TiO2 generates hydroxyl radicals (・OH) under ultraviolet light excitation, oxidizing and decomposing the bacterial cell membrane. This synergistic effect results in an inactivation rate of ≥99.9% against viruses (such as influenza viruses) without secondary pollution. The third layer of chemical slow-release enhancement utilizes the lower layer containing... Chlorine disinfectant tablets (50% effective chlorine content) dissolve slowly, releasing hypochlorous acid (HClO) to deeply disinfect residual microorganisms after the first two treatments, ensuring that the total bacterial count in the effluent is ≤10 CFU / mL (meeting the standards for domestic miscellaneous water). Furthermore, by controlling the dissolution rate (0.5 g / h), excessive residual chlorine is prevented from causing equipment corrosion or odor. The adsorption purification layer 57 uses mesoporous activated carbon to adsorb oil stains (such as lubricating oil dripping from construction machinery), and bamboo fiber enhances hydrophilicity, solving the problems of traditional activated carbon's "slow water absorption and easy caking." The slow-release scale inhibitor layer 58 releases phosphonates from the ceramic particles, inhibiting the formation of scale from calcium and magnesium ions in the circulating water and preventing clogging of the water curtain nozzles 4 (traditional filters do not consider scale inhibition, and are prone to scale buildup with long-term use). Wastewater passes through a coarse filtration interception layer 53 (removing large particles) → a magnetic flocculation layer 54 (aggregating fine particles) → an ultrafine filtration layer 55 (intercepting particles smaller than 1μm + preliminary antibacterial action) → an antibacterial disinfection layer 56 (triple synergistic inactivation of microorganisms) → an adsorption purification layer 57 (removing oil and adsorbing disinfection byproducts) → a slow-release scale inhibitor layer 58 (preventing scaling), controlling the final effluent turbidity to ≤5 NTU and the total bacterial count to ≤10 CFU / mL, and can be safely reused in water curtain systems.

[0048] The magnetic ceramsite, by weight, comprises 25-30 parts of magnetite (Fe3O4) magnetic powder, 35-40 parts of clay, 15-20 parts of fly ash, 8-10 parts of perlite, 2-3 parts of zinc oxide, and 3-5 parts of sodium silicate. The 25-30 parts of magnetite magnetic powder impart remanence (weak to moderate magnetism) to the ceramsite, enabling it to be adsorbed or guided by the strong magnetic field of neodymium iron boron (NdFeB), while simultaneously enhancing its ability to capture magnetic particles in water, thus providing magnetism and responding to external magnetic fields. The 35-40 parts of clay provide the basic framework for the ceramsite, forming a hard outer shell after high-temperature sintering to ensure structural strength. The 15-20 parts of fly ash utilize industrial waste, reducing costs, and during sintering, the combustion of carbon components creates a porous structure, enhancing adsorption. The 8-10 parts of perlite expand at high temperatures, creating pores, reducing the density of the ceramsite (facilitating water penetration), and increasing the porosity to 30%-50%. Zinc oxide (2-3 parts) acts as an antibacterial agent, inhibiting bacterial growth on the surface of the ceramsite and preventing secondary pollution, targeting bacteria that may proliferate in subway wastewater (such as sweat from construction workers and microorganisms in the soil). Sodium silicate (3-5 parts) acts as a binder, improving the stability of the raw material during molding and preventing cracking during sintering.

[0049] The porous calcium carbonate ceramsite comprises, by weight, 60-70 parts of light calcium carbonate, 15-20 parts of fly ash, 5-10 parts of bentonite, 3-5 parts of HEDP phosphonate, and 2-3 parts of sodium bicarbonate. Light calcium carbonate provides the main framework, serving as a carrier for the scale inhibitor. Its self-dissolution can regulate the calcium hardness in water and inhibit scale crystallization. Light calcium carbonate with a particle size of 1-5μm is selected, which has a high specific surface area, facilitating the adsorption and loading of scale inhibitors. It can slowly dissolve in water, releasing Ca²⁺, and inhibiting the combination of excess Ca²⁺ and Mg²⁺ with carbonate ions to form scale (CaCO3, MgCO3) through the "common ion effect," thus reducing scale formation at the source. Fly ash introduces a glassy phase and porous structure, reducing the density of the ceramsite and increasing the porosity (promoting the slow release of the scale inhibitor). Industrial waste (containing SiO2, Al2O3, etc.) is low in cost and has pozzolanic activity. During sintering, it reacts with calcium carbonate to form a glassy phase, enhancing the strength of the ceramsite. The micropores on the particle surface are retained after sintering, forming a continuous porous structure together with the pores generated by the foaming agent, providing channels for the slow release of the scale inhibitor. Bentonite contains clay minerals such as montmorillonite, which expands upon contact with water, improving the plasticity of the raw material. During sintering, it forms a stable porous structure, facilitating granulation (ensuring uniform particle size, controlled within 2-3 mm). HEDP phosphonate, as a slow-release scale inhibitor, is loaded into the pores of the ceramic particles, slowly releasing to inhibit the scaling of calcium and magnesium ions in the water. It is loaded into the pores of the ceramic particles through physical adsorption or chemical bonding. The porous structure of the ceramic particles can control the dissolution rate of the scale inhibitor (e.g., releasing 0.05-0.1 g / m² per hour), continuously interfering with the growth of scale crystals and preventing scale buildup and clogging of nozzles and pipes. Sodium bicarbonate is used as a foaming agent. When sodium bicarbonate (NaHCO3) is sintered at 600-800℃, it decomposes into CO2, forming uniformly distributed pores inside the ceramic particles, so that the porosity reaches 40%-60%. The pore size is controlled by the amount of foaming agent. For example, when the amount is 2%-3%, the pore size is 50-200μm, which improves the slow release efficiency, ensuring that the scale inhibitor can slowly seep out while avoiding excessive loss.

[0050] See appendix Figure 1The rotary lifting mechanism includes a dual-axis motor 8, a rotating disk 9, and a screw. An annular hole 10 is provided on the end wall of the base 1 facing the nozzle 2. The end wall portion within the annular hole 10 forms the rotating disk 9. The annular hole 10 is used to avoid obstructing the rotation of the rotating disk 9. An electromagnetic clutch assembly 12 and an electromagnetic clutch assembly 13 are provided on the motor shaft 11 of the dual-axis motor 8. A drive gear 14 is provided on the electromagnetic clutch assembly 12, which is connected to driven gears 16 located on either side of it via a transmission belt 15. A screw 17 is provided on the driven gear 16, passing through the rotating disk 9. The electromagnetic clutch assembly 13 is located at the central shaft hole of the rotating disk 9. An electromagnetic clutch assembly 19 is also provided on the motor shaft 18 of the dual-axis motor 8, located at the central shaft hole of the circular filter screen 7. The dual-axis motor 8 drives the filter screen 7 to rotate, preventing the filter screen 7 from becoming clogged. In this application, the dual-shaft motor 8 and electromagnetic clutch assemblies one to three are all controlled by PLC 20. PLC 20 can selectively control the start and stop of electromagnetic clutch assemblies one to three to control the rotation start and stop of the components that cooperate with the electromagnetic clutch assemblies. That is, it controls the components to rotate synchronously with the motor shaft, or not to rotate synchronously with the motor shaft, maintaining a non-rotating state and not affected by the rotation of the motor shaft. The detailed connection settings between the electromagnetic clutch assembly and the motor shaft, and between the electromagnetic clutch assembly and external components, including whether other auxiliary parts are used, are all prior art in this application and will not be described in detail here.

[0051] See appendix Figure 1After the motor shaft 218 passes through the filter screen 7, an electromagnetic clutch assembly 4 21 is installed on it. The electromagnetic clutch assembly 4 21 is equipped with a drive gear 22. The drive gear 22 is connected to the driven gears 24 located on both sides of it through a transmission belt 23. The driven gear 24 is equipped with a screw 25. The screw 25 passes through the purification layer 26 and is installed on the base 1. The screw 25 is equipped with a screw block 27, which is located between the screw 25 and the purification layer 26. The electromagnetic clutch assembly 4 21 is controlled by a PLC 20. The PLC 20 can selectively control the start and stop of the electromagnetic clutch assembly 4 21 to control the rotation start and stop of the components that cooperate with the electromagnetic clutch assembly. The PLC 20 controls the dual-axis motor 8 and the electromagnetic clutch assembly 21 to open. The driving gear 22 drives the driven gear 24 and the screw 25 on it to rotate. The PLC 20 sets the motor shaft 18 of the dual-axis motor 8 to rotate periodically in both directions. The purification layer 26, along with the screw block 27, enters the accumulated water along the screw 25 (entering only to a certain depth or completely submerged to avoid affecting the purification effect), and then leaves the accumulated water, moving up and down in the water. The lower part of the accumulated water provides a large upward impact force to the purification layer 26, which serves to backwash the purification layer 26, dispersing the filter residue deposited on the surface and in the gaps of the purification layer 26, and simultaneously purifying the newly entering sewage, thereby improving the purification effect of subsequent sewage in real time. As mentioned above, the purification layer 26 can be arranged in multiple layers at intervals, with each layer connected to the screw by the screw block 27. The vertically movable seal between the edge of the purification layer 26 and the base 1 adopts the existing technology in this field and will not be described in detail.

[0052] A spray pipe 2 is vertically mounted on the screw 17. A splash-proof layer 28, such as a sponge, is provided on the rotating disk 9 to prevent water splashing and forming smog. A water supply pipe 29 is also connected to the side wall corresponding to the water accumulation part of the base 1 for external water intake to the base 1. The pumping device 30 includes an electrically controlled dual-outlet water pump, and its other outlet is connected to a second water pipe 31. The outlet of the second water pipe 31 is located between the sewage filtration mechanism and the sewage purification mechanism for pumping water to that location.

[0053] See Figure 1It also includes a smog extraction mechanism, which includes an air pump 32 with dual air inlets controlled by a solenoid valve 60, an air inlet pipe 33, an air passage 1 34, an air passage 2 35, and an air outlet pipe 36. One air inlet of the air pump 32 is connected to one end of the air inlet pipe 33, and the other end of the air inlet pipe 33 is connected to the nozzle 2. The other air inlet of the air pump 32 is connected to the air passage. The air passage 1 34 and the air passage 2 35 are respectively installed through the side wall of the base 1. The air passage 1 34 is located between the filter screen 7 and the rotating disk 9, and the air passage 2 35 is located on the side wall corresponding to the water accumulation part of the base 1. The air outlet of the air pump 32 is connected to one end of the air outlet pipe 36, and the other end of the air outlet pipe 36 is connected to the air passage 2 35. The device also includes a dust concentration sensor 37 and a haze particle sensor 38, both connected to a PLC 20. The dust concentration sensor 37 detects the dust concentration in the tunnel atmosphere in real time. When the PLC 20 determines that the concentration exceeds a set value of 50 mg / m³, the PLC 20 controls the dual-channel water pump to start, supplying water to the spray pipe 2 through the first water pipe 3. Multiple nozzles 4 of the spray pipe 2 spray water towards the water curtain recovery mechanism, forming a water curtain to reduce dust. When the haze particle sensor 38 detects the haze particle concentration in real time, and the PLC 20 determines that the haze particle concentration exceeds a threshold (such as PM2.5 > 75 μg / m³ and / or PM10 > 150 μg / m³), the sensor detects the dust concentration exceeding a threshold value. (g / m³), PLC20 further determines that if the nozzle 2 does not spray water (by detecting whether the nozzle 4 is open) and there is no water accumulation (by detecting the water accumulation sensor 39 inside the nozzle 2), then it controls the air pump 32 to turn on, drawing the nozzle 2 into negative pressure through the air inlet pipe 33, and simultaneously drawing the area above the water accumulation part of the base 1 into negative pressure through the second air passage 35. The fog and haze in the tunnel are drawn into the air pump 32 through the nozzle 2 and the base 1, and discharged into the water accumulation for filtration through the air outlet pipe 36 and the second air passage 35. The air overflowing from the water accumulation is purified by the purification layer 26 and then discharged. To improve the disinfection effect, a certain amount of bactericide and disinfectant can be added to the water accumulation. As a more effective alternative, the second air passage 35 can be installed between the filter 7 and the purification layer 26, and the air outlet 36 enters the base 1 through the second air passage 35. Its air outlet is fixed on the purification layer 26 and can move up and down synchronously with the purification layer 26. When preparing to extract smog, the purification layer 26 is first lowered and submerged in the water. The smog that enters is captured by the water and then effectively purified by the purification layer 26 before entering the water accumulation section below the base 1.

[0054] The device also includes a laser particle size sensor 40, a laser turbidity meter 41, and a PLC 20 for detecting particle concentration. The laser particle size sensor 40 and the laser turbidity meter 41 are installed between the filter screen 7 and the purification layer 26 to detect the raw water impurity load entering the purification layer 26 in real time and transmit the data to the PLC 20. For example, when the PLC 20 determines that the particle concentration is >5 mg / L or the turbidity is >5 NTU, it controls the electrically controlled dual-channel water pump to replenish water between the filter screen 7 and the purification layer 26 through the second water pipe 31 to reduce the purification load. This step is for pretreatment monitoring.

[0055] The device also includes a differential pressure sensor group 42, which is installed on the upper and lower surfaces of the coarse filter interception layer 53. It is used to detect the sewage pressure before and after filtration by the coarse filter interception layer 53 in real time and transmit it to the PLC 20. When the PLC 20 determines, for example, that the pressure difference is >0.15MPa, it determines that the coarse filter interception layer 53 is saturated. The PLC 20 controls the purification layer 26 to move up and down in the water along the screw 25 with the screw block 27, which plays the role of backwashing the coarse filter interception layer 53. This step is for monitoring the purification layer efficiency.

[0056] The device also includes a ferromagnetic particle counter group 43, which is set between the magnetic flocculation layer 54 and the ultrafine filter layer 55. It detects the magnetic particle concentration in real time and transmits the data to the PLC 20. When the PLC 20 determines, for example, that the magnetic particle concentration is >2mg / L, it determines that the magnetic flocculation layer 54 needs maintenance. An electromagnetic pulse generator 44 is set in the magnetic flocculation layer 54. When the electromagnetic pulse generator 44 is turned on, a 1Hz high-frequency pulsed magnetic field is used to vibrate and desorb the magnetic particles. At the same time, the PLC 20 controls the purification layer 26 to move up and down in the water along the screw 25 with the screw block 27, which has the effect of backwashing the coarse filter interception layer 53 and reducing the adsorption of the magnetic flocculation layer 54. This step is for monitoring the purification layer's effectiveness.

[0057] The device also includes a Zeta potential meter 45 and a TOC sensor 46 disposed between the ultrafine filter layer 55 and the antibacterial disinfection layer 56. The Zeta potential meter 45 detects colloidal residue in real time, and the TOC sensor 46 detects total organic carbon concentration in real time and transmits the data to the PLC 20 in real time. When the PLC 20 determines, for example, that the absolute value of the colloidal Zeta potential is <20mV or the TOC is >3mg / L, it determines that the ultrafine filter layer 55 is saturated. The PLC 20 controls the dual-axis motor 8 and the electromagnetic clutch assembly 21 to open. The driving gear 22 drives the driven gear 24 and the screw 25 on it to rotate. The PLC 20 sets the motor shaft 18 of the dual-axis motor 8 to rotate periodically in both directions. The purification layer 26 moves up and down in the water along the screw 25 with the screw block 27, which has the effect of backwashing the coarse filter interception layer 53. This step is for monitoring the efficiency of the purification layer.

[0058] The device also includes a fluorescent biosensor 47, a conductivity sensor 48, a laser turbidimeter 49, and a residual chlorine sensor 50, all installed in the water accumulation section. The fluorescent biosensor 47 is used to detect the total bacterial count and virus titer. The residual chlorine sensor 50 is used to detect the chlorine concentration in the water. The conductivity sensor 48 is used to detect the content of dissolved salts (such as calcium, magnesium ions, and chloride ions) in the water. The oil content sensor is used to detect the oil content in the water. All sensors are connected to a PLC 20. For example, if the total bacterial count is <100 CFU / mL and the virus titer is <100 CFU / mL... Water quality is considered acceptable if the concentration is <50 pfu / mL, turbidity <1 NTU, oil concentration <5 mg / L, and conductivity <500 μS / cm. If any one of these conditions is not met, PLC 20 controls the second water pipe 31 to pump the accumulated water between the filter screen 7 and the purification layer 26 for re-purification. Simultaneously, the water flow from the first water pipe 3 is stopped. If the microbial indicators exceed the standard during re-purification, the UV lamp irradiation time is extended until the accumulated water meets the standard. Additionally, if the chlorine concentration (0.05-0.3 mg / L) is not met, the chlorine disinfection tablets built into the PVC mesh plate need to be replaced. Furthermore, if the purified water is deemed unacceptable, the PLC 20 controls the purification layer 26 to move up and down along the screw 25 with the screw block 27 in the accumulated water, performing a reverse flushing of the purification layer 26. This step is a final inspection before the cycle.

[0059] The device also includes a water level sensor 51 and a water level sensor 52 installed at different heights of the water accumulation section, and each is connected to a PLC 20. When the water level is lower than that of the water level sensor 51, the PLC 20 opens the solenoid valve 60, and water enters the base 1 through the external water pipe. When the water level is higher than that of the water level sensor 52, the PLC 20 closes the solenoid valve 60, and water enters the external water pipe.

[0060] For the detection of purification layer 26, this solution uses a multi-level linkage detection + dynamic closed-loop adjustment mechanism to achieve standard judgment of the recycling of purified water and automatic treatment of substandard water. The core is to upgrade the traditional single detection (only detecting the water quality after purification) to a full-process control of "pretreatment monitoring - purification layer efficiency monitoring - pre-circulation final inspection". Combined with the self-cleaning and graded maintenance triggering logic of purification layer 26, it solves the pain point of "passive maintenance after purification effect loss" caused by only detecting the water quality after purification in the existing technology. That is, it breaks through the traditional passive mode of "detection-alarm" and achieves full-cycle control of "prevention-adjustment-maintenance" through the combination of three-level detection and tiered treatment. The self-cleaning and dynamic water replenishment mechanism of purification layer 26 can extend the life of consumables by more than 30%.

[0061] All the values ​​used by the PLC20 mentioned above to determine the compliance standard are threshold values, which are pre-stored in the PLC20 and can also be manually entered and modified.

[0062] The dust removal method of the device in this application includes the following steps:

[0063] 1) Determine whether it is necessary to turn on the water curtain and / or remove smog based on the detection value. If both are required, turn on the water curtain first.

[0064] 2) After the water curtain is turned on, during the pretreatment monitoring stage, the system will determine in real time whether the purification load needs to be reduced in the pretreatment monitoring step based on the detection value. If so, emergency water will be added between the filter screen 7 and the purification layer 26.

[0065] 3) During the purification layer performance monitoring stage, the working status of each layer in the purification layer 26 is judged in real time based on the detection value. If the status is abnormal, the backwashing mode is turned on, which can filter while backwashing, and at the same time and / or issue alarms such as inspection and repair materials.

[0066] 4) During the final inspection stage before circulation, the purified water is judged in real time based on the test values. If it is not qualified, the microbial content is analyzed first. If so, the PLC20 controls the extension of the ultraviolet lamp irradiation time.

[0067] 5) Based on step 4), the residual chlorine concentration in the accumulated water is analyzed to see if it meets the requirements. If it does not meet the requirements, it is determined that the chlorine disinfectant tablets built into the PVC mesh panel need to be replaced, and an alarm is issued.

[0068] 6) Based on the completion of steps 4)-5), control the second water pipe 31 to pump the accumulated water into the space between the filter screen 7 and the purification layer 26 for re-purification, and at the same time control the stop of water output from the first water pipe 3;

[0069] 7) Based on the start of step 6), the backwash mode is started simultaneously, which can filter while backwashing, thus improving the purification effect;

[0070] 8) If the detection value indicates that smog extraction is needed, and it is detected that the water curtain is not turned on, first check whether there is water accumulation inside the spray nozzle;

[0071] 9) If there is no water accumulation in the spray nozzle, turn on the fog extraction mode until the fog concentration meets the requirements or the water curtain needs to be turned on.

[0072] 10) During the above steps, PLC20 ensures that the water level is within a reasonable range by using water level detection data.

[0073] The above steps are programmed into the PLC20 to achieve automated mechanical control.

Claims

1. An atmospheric dust removal device for subway tunnel construction, comprising a base (1) and a water curtain mechanism, characterized in that, It also includes a rotating lifting mechanism. The water curtain mechanism can be rotated and lifted on the base (1) through the rotating lifting mechanism. The base (1) is equipped with a water curtain recycling mechanism, a sewage filtration mechanism and a sewage purification mechanism. The water curtain recycling mechanism recycles the water curtain for filtration by the sewage filtration mechanism and purification by the sewage purification mechanism. The purified water re-enters the water curtain mechanism. The water curtain mechanism includes components with a vertical cross-section and a " The nozzle (2) is shaped and has a square cross-section, a pumping device (30) and a first water pipe (3). The bottom of the nozzle (2) is provided with a base (1). Multiple nozzles (4) are provided on one side wall of the nozzle (2) facing the base (1). The nozzles (4) are in the shape of a Venturi tube. The multiple nozzles (4) spray water toward the water curtain recovery mechanism to form a water curtain. The nozzle (2) is connected to the pumping device (30) through the first water pipe (3). The water curtain recycling mechanism includes water holes (5) opened on the base (1), and the water curtain flows to the sewage filtration mechanism through the water holes (5). The sewage filtration mechanism includes a filter screen (7) installed in the base (1). The rotary lifting mechanism includes a dual-axis motor (8), a rotating disk (9), and a screw. An annular hole (10) is provided on the end wall of the base (1) facing the nozzle (2). The end wall portion inside the annular hole (10) forms the rotating disk (9). An electromagnetic clutch assembly one (12) and an electromagnetic clutch assembly two (13) are provided on the motor shaft one (11) of the dual-axis motor (8). An active gear one (14) is provided on the electromagnetic clutch assembly one (12). The active gear one (14) is connected to a transmission belt one (15) via a transmission belt one (16). The driven gears (16) located on both sides are connected. A screw (17) is provided on the driven gear (16). The screw (17) passes through the rotating disk (9). A nozzle (2) is provided on the screw (17) and can be raised and lowered. An electromagnetic clutch assembly (13) is provided at the central shaft hole of the rotating disk (9). An electromagnetic clutch assembly (19) is provided on the motor shaft (18) of the dual-axis motor (8). The electromagnetic clutch assembly (19) is provided at the central shaft hole of the circular filter screen (7).

2. The atmospheric dust removal device for subway tunnel construction as described in claim 1, characterized in that, After the motor shaft (18) passes through the filter screen (7), an electromagnetic clutch assembly (21) is provided on it. An active gear (22) is provided on the electromagnetic clutch assembly (21). The active gear (22) is connected to the driven gears (24) located on both sides of it through the transmission belt (23). A screw (25) is provided on the driven gear (24). The screw (25) passes through the sewage purification mechanism and is provided on the base (1). A screw block (27) is provided on the screw (25). The screw block (27) is located between the screw (25) and the purification layer (26).

3. The atmospheric dust removal device for subway tunnel construction as described in claim 1, characterized in that, It also includes a smog extraction mechanism, which includes an air pump (32) with dual air inlets controlled by a solenoid valve (60), an air inlet pipe (33), an air passage one (34), an air passage two (35), and an air outlet pipe (36). One air inlet of the air pump (32) is connected to one end of the air inlet pipe (33), and the other end of the air inlet pipe (33) is connected to the nozzle (2). The other air inlet of the air pump (32) is connected to the air passage. The air passage one (34) and the air passage two (35) are respectively installed through the side wall of the base (1). The air passage one (34) is located between the filter screen (7) and the rotating disk (9), and the air passage two (35) is located at the side wall of the base (1). The air outlet of the air pump (32) is connected to one end of the air outlet pipe (36), and the air outlet pipe (36) is connected to the water accumulation part of the base (1) through the air passage two (35).

4. The atmospheric dust removal device for subway tunnel construction as described in claim 1, characterized in that, The pumping device (30) includes an electrically controlled dual-outlet water pump, the other outlet of which is connected to a second water pipe (31), the outlet of which is located between the sewage filtration mechanism and the sewage purification mechanism.

5. The atmospheric dust removal device for subway tunnel construction as described in claim 3, characterized in that, After the air outlet pipe (36) passes through the second air passage (35), its air outlet is fixedly installed on the sewage purification mechanism and located between the sewage filtration mechanism and the sewage purification mechanism.

6. The atmospheric dust removal device for subway tunnel construction as described in claim 1, characterized in that, The rotating disk (9) is provided with a splash-proof layer (28), and a water supply pipe (29) is connected to the side wall corresponding to the water accumulation part of the base (1). The bottom of the atmospheric dust removal device for subway tunnel construction is provided with rollers (59), and the side wall of the atmospheric dust removal device for subway tunnel construction is provided with a push handle. The base (1) is a hollow cylinder, and the edge of its upper end face protrudes to form an annular flange (6) to block splashing water. The shaped nozzle (2) is arranged radially along the rotating disk (9).

7. The atmospheric dust removal device for subway tunnel construction as described in claim 1, characterized in that, The wastewater purification mechanism includes a layered purification layer (26) located in the base (1) below the filter screen (7). The purification layer (26) includes a coarse filtration interception layer (53) that intercepts silt particles and fiber impurities of not less than 20 μm, a magnetic flocculation layer (54) that adsorbs ferromagnetic particles and enhances colloidal coagulation, an ultrafine filtration layer (55) that intercepts fine dust and colloids of 1-20 μm, an antibacterial disinfection layer (56), a purification layer (57) that adsorbs oil, removes odors and adsorbs some heavy metals, and a slow-release scale inhibitor layer (58) that prevents calcium and magnesium ion scaling.

8. The atmospheric dust removal device for subway tunnel construction as described in claim 1, characterized in that, The nozzle (2) also has multiple Venturi tube-shaped nozzles (4) on its other side walls. Each nozzle (4) is equipped with a solenoid valve (60). The solenoid valve (60), pumping device (30), air pump (32), electromagnetic clutch assembly, and dual-shaft motor (8) are all connected to PLC (20).

9. The atmospheric dust removal device for subway tunnel construction as described in claim 7, characterized in that, The atmospheric dust removal device for subway tunnel construction also includes a dust concentration sensor (37), a haze particle sensor (38), a water accumulation sensor (39), and a water level sensor 1 (51) and a water level sensor 2 (52) set at different heights in the water accumulation section, and is connected to a PLC (20) respectively. The dust concentration sensor (37) detects the dust concentration in the tunnel atmosphere in real time, the haze particle sensor (38) detects the haze particle concentration in real time, and the water accumulation sensor (39) detects whether there is water accumulation in the nozzle (2) in real time.

Images