Foundation pit car washing pool wastewater purification and sludge filter pressing one-stop green recycling method

Abstract

The present application relates to the technical field of foundation pit, disclose a kind of green recycling method of foundation pit car wash pool wastewater purification and sludge filter pressing one-stop, car wash wastewater is discharged into sedimentation structure, and the sedimentation structure has multiple sedimentation tanks, and car wash wastewater flows and forms particle precipitate and sedimentation wastewater by sedimentation;Sedimentation wastewater is discharged into purification treatment structure, and sedimentation wastewater is synchronously discharged into reaction tank with flocculation medicine water and is stirred to form reaction wastewater, and reaction wastewater is discharged into water distribution tank and is buffered and stabilized to form sludge and purified water;Sludge and purified water are discharged into flocculation tank, and purified water is overflowed into overflow tank through overflow weir, and purified water in overflow tank is discharged into water storage barrel through pipeline;High-pressure gas and sludge are injected into filter pressing area of filter press through feed pipe, sludge is formed into cake in filter pressing area by filter pressing, water in sludge is filtered to form filtered water through filter cloth, and filtered water is discharged into water storage barrel through pipeline.

Description

Technical Field

[0001] This invention patent relates to the technical field of foundation pits, specifically to a one-stop green recycling method for the purification of wastewater from foundation pit car wash pools and sludge depressurization. Background Technology

[0002] The Guimiao New Village Urban Renewal Project General Contracting Project is located at the intersection of Baishi Road and Xuefu Road, Yuehai Subdistrict, Nanshan District, Shenzhen, covering an area of ​​41,660.1 square meters. 2 The foundation pit has a perimeter of 991m and an excavation area of ​​40499m². 2 The excavation depth of the foundation pit ranged from 12.00 to 17.80 meters, with a total earthwork excavation volume of 603,435 cubic meters. 3 During the excavation of the foundation pit, a large amount of waste soil was transported off-site by dump trucks, at a rate of 10m³ per truck. 3 Based on the carrying capacity calculation, 60,344 dump truck trips are needed to complete the excavation of the foundation pit. To ensure the environmental cleanliness of the roads where the dump trucks travel, the truck bodies must be washed before leaving the construction site.

[0003] In existing technology, washing facilities are installed at the construction site entrance and exit. Vehicles are initially washed using a car wash pool, and then manually rinsed until they meet road safety standards. The daily water consumption for car washing and road rinsing is approximately 300 cubic meters. 3 It consumes a large amount of clean water resources; and when pile foundation construction and large-scale excavation of foundation pits are carried out, traditional drainage systems often cannot meet the on-site sewage discharge requirements, and the three-stage sedimentation tank cannot achieve good treatment effect, so that the untreated sludge and wastewater are discharged into the municipal pipe network, causing pollution or even blockage of municipal pipes. Summary of the Invention

[0004] The purpose of this invention is to provide a one-stop green recycling method for the purification of wastewater from car wash pits and the filtration of sludge. This method aims to solve the problems in the existing technology where a large amount of polluted wastewater from car washing and road washing cannot be effectively treated, causing pollution or even blockage of municipal pipelines, and the inability to effectively utilize polluted wastewater, resulting in high water consumption and high costs for car washing.

[0005] This invention is implemented as follows: a one-stop green recycling method for purifying wastewater and dewatering sludge from a car wash pit includes the following steps:

[0006] 1) The car wash wastewater in the car wash pool is discharged into the sedimentation structure, which has multiple sedimentation tanks arranged in sequence and side by side, and the tops of adjacent sedimentation tanks are interconnected; the car wash wastewater flows through the multiple sedimentation tanks in sequence to form particulate sediments settled at the bottom of the sedimentation tanks and settled wastewater discharged from the sedimentation tanks.

[0007] 2) The sedimented wastewater is discharged into the purification treatment structure, which includes a reaction tank, a water distribution tank, a flocculation tank and an overflow tank. The reaction tank, water distribution tank, flocculation tank and overflow tank are connected in sequence and arranged side by side. An overflow weir is provided between the flocculation tank and the overflow tank.

[0008] The sedimentation wastewater and flocculation solution are simultaneously discharged into the reaction tank for stirring and reaction, forming reaction wastewater. The reaction wastewater is then discharged into the distribution tank for buffering and stabilization, forming sludge that settles in the lower part of the distribution tank and is composed of suspended solids, colloids, and flocculated flocs, as well as purified water that forms in the upper part of the distribution tank. The sludge and purified water are then discharged into the flocculation tank, where the sludge settles in the lower part and the purified water is located in the upper part. The purified water overflows into the overflow tank through the overflow weir, and the purified water in the overflow tank is discharged into the storage tank through a pipe.

[0009] 3) The sludge is discharged into the filter press through the feed pipe. The filter press includes multiple filter plates arranged side by side and moving away from or towards each other. Filter cloth is covered on both sides of each filter plate. The two filter cloths on the filter plate and the filter plate surround each other to form a water filtration zone. When the adjacent filter plates are in a state of mutual pressure, the adjacent filter plates surround each other to form a filtration zone. The filtration zone is located between two water filtration zones.

[0010] Multiple filter plates are pressed against each other to form a sealed filter press zone between adjacent filter plates. High-pressure gas and sludge are injected into the filter press zone through the feed pipe. The sludge is pressed and filtered in the filter press zone to form a sludge cake. The water in the sludge is filtered through the filter cloth and enters the water filtration zone to form filtered clean water. The filtered clean water is discharged into the water storage tank through the pipe.

[0011] Optionally, in construction step 1), the multiple sedimentation tanks include a first sedimentation tank, multiple intermediate sedimentation tanks, and a last sedimentation tank. The first sedimentation tank, multiple intermediate sedimentation tanks, and last sedimentation tank are arranged side by side in sequence. After the car wash wastewater is discharged into the first sedimentation tank, it flows sequentially along the multiple intermediate sedimentation tanks and the last sedimentation tank. The particulate matter in the car wash wastewater settles in the lower part of the first sedimentation tank, the lower part of the multiple intermediate sedimentation tanks, and the lower part of the last sedimentation tank, respectively. The settled wastewater is formed in the upper part of the last sedimentation tank.

[0012] Optionally, the car wash pool is connected to the first-end sedimentation tank via a drainage ditch, and the car wash wastewater in the car wash pool is discharged into the first-end sedimentation tank via the drainage ditch.

[0013] Optionally, in construction step 2), the flocculant solution is formed by mixing polyacrylamide and water, and the ratio of polyacrylamide to water is 1:(450-550) according to mass ratio.

[0014] Optionally, in construction step 2), the reaction tank is equipped with a stirrer, and after the precipitated wastewater and flocculant are placed in the reaction tank, the stirrer continuously stirs and mixes the precipitated wastewater and flocculant.

[0015] Optionally, in construction step 2), the reaction wastewater in the reaction tank is kept in a flowing state, and a reaction connection port is provided at the bottom of the reaction tank. The flowing reaction wastewater in the reaction tank is discharged from bottom to top to the water distribution tank through the reaction connection port for buffering and stabilization.

[0016] Optionally, in construction step 2), the lower part of the water distribution tank is provided with a water distribution connection port, and the sludge and purified water in the water distribution tank are discharged from bottom to top into the flocculation tank through the water distribution connection port.

[0017] The bottom of the flocculation tank is concave, forming multiple concave areas that are larger at the top and smaller at the bottom. These multiple concave areas are arranged sequentially along the flow direction of the purified water in the flocculation tank, and the tops of adjacent concave areas are interconnected.

[0018] As the sludge and purified water flow along the flocculation tank, the sludge settles in multiple recessed areas and remains stationary, while the purified water is located at the top of the multiple flocculation tanks and is in a flowing state.

[0019] Optionally, in construction step 2), the top of the overflow weir extends upward to form an overflow tip; along the width direction of the flocculation tank, the overflow tip is arranged in multiple curved sections to form a wave-like arrangement; the purified water in the flocculation tank passes over the overflow tip and enters the overflow tank.

[0020] Optionally, the feed pipe is equipped with a suction pump, and the inner end of the feed pipe is connected to multiple recessed areas respectively; the inner end of the feed pipe has a suction section extending into the recessed area, the suction section extends upward from the bottom of the recessed area and then bends downward, and the end of the suction section forms an end suction port.

[0021] The suction section has multiple elastic sections made of elastic adhesive layers and multiple hard sections made of hard adhesive layers. The multiple elastic sections and multiple hard sections are arranged at intervals along the length direction of the suction section, and the hard sections are located between two adjacent elastic sections. The hard sections are provided with multiple side suction ports, and the multiple side suction ports are arranged at staggered intervals along the circumference of the hard sections.

[0022] In construction step 3), the suction pump uses a variable frequency drive to suction sludge from the depression area through the feed pipe. As the amount of sludge entering the suction section changes, the elastic section undergoes reciprocating expansion and contraction deformation, forming elastic compression and peristalsis on the sludge in the suction section, thus limiting the sludge from forming blockages in the suction section.

[0023] Optionally, the end suction port is covered with an elastic mesh layer, the outer periphery of the elastic mesh layer is fixedly connected to the suction section, and the middle part of the elastic mesh layer is suspended and covers the end suction port to form an elastic part; the outer side of the elastic part has an outwardly arc-shaped protruding outer mesh layer, and the inner side of the elastic part has an inwardly arc-shaped protruding inner mesh layer, the outer periphery of the outer mesh layer and the outer periphery of the inner mesh layer are joined together, and the middle parts of the outer mesh layer and the middle parts of the inner mesh layer are arranged separately to form an elastic space;

[0024] In construction step 3), the suction pump uses a variable frequency drive to suction sludge from the recessed area through the feed pipe. The sludge passes through the outer convex mesh layer, the elastic space, and the inner convex mesh layer in sequence before entering the suction section. The outer and inner convex mesh layers are squeezed by the sludge and undergo reciprocating elastic deformation, which limits the sludge from forming a blockage at the suction port. During the process of the sludge passing through the outer and inner convex mesh layers, it is elastically squeezed by the outer and inner convex mesh layers and dispersed.

[0025] Compared with existing technologies, the present invention provides a one-stop green recycling method for the purification and sludge dewatering of car wash wastewater in pits. This method removes particulate matter from the wastewater through a five-stage sedimentation process using a sedimentation structure. The wastewater is then reacted with flocculant in a reaction tank, causing suspended solids, colloids, and flocculated particles to form sludge. This effectively treats the wastewater into purified water and sludge. The sludge is then dewatered using a filter press to form mud cakes and filtered water. Both the filtered and purified water are stored together in a storage tank via pipelines. In this way, car wash wastewater is converted into mud cakes and purified water through a one-stop purification system. The purified water is used for on-site production, car washing, dust suppression, and road cleaning, resulting in a thorough overall treatment process. On the one hand, this significantly reduces the discharge of sludge and wastewater, preventing pollution of municipal pipelines. On the other hand, the purified water is used for car washing, achieving the recycling of polluted wastewater, saving costs, and being a green and pollution-free practice. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the process for the one-stop green recycling method of wastewater purification and sludge depressurization in a foundation pit car wash pool provided by the present invention.

[0027] Figure 2 This is a schematic diagram showing the layout of the drainage ditch, sedimentation structure, purification treatment structure, filter press, and water storage tank provided by the present invention.

[0028] Figure 3 This is a schematic diagram of the purification treatment structure provided by the present invention;

[0029] Figure 4 This is a schematic diagram of the filter press provided by the present invention;

[0030] Figure 5This is a schematic diagram of the structure of the filter plate and filter cloth provided by the present invention;

[0031] Figure 6 This is a partial schematic diagram of the purification treatment structure provided by the present invention;

[0032] Figure 7 This is a schematic diagram of the connection between the flocculation tank and the feed pipe provided by the present invention;

[0033] Figure 8 This is a partial cross-sectional schematic diagram of the feed pipe provided by the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0035] The implementation of the present invention will be described in detail below with reference to specific embodiments.

[0036] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this invention, it should be understood that if terms such as "upper," "lower," "left," and "right" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the accompanying drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0037] Reference Figure 1-8 The image shown is a preferred embodiment of the present invention.

[0038] The present invention provides a one-stop green recycling method for the purification of wastewater and sludge dewatering in car wash pits, comprising the following steps:

[0039] 1) The car wash wastewater in the car wash pool is discharged into the sedimentation structure 100. The sedimentation structure 100 has multiple sedimentation tanks arranged in sequence and side by side, and the tops of adjacent sedimentation tanks are interconnected. The car wash wastewater flows through the multiple sedimentation tanks in sequence to form particulate sediments settled at the bottom of the sedimentation tanks and settled wastewater discharged from the sedimentation tanks.

[0040] 2) The sedimented wastewater is discharged into the purification treatment structure 200, which includes a reaction tank 201, a water distribution tank 202, a flocculation tank 203 and an overflow tank 204. The reaction tank 201, water distribution tank 202, flocculation tank 203 and overflow tank 204 are connected in sequence and arranged side by side. An overflow weir 210 is provided between the flocculation tank 203 and the overflow tank 204.

[0041] The sedimentation wastewater and flocculation solution are simultaneously discharged into the reaction tank 201 for stirring and reaction, forming reaction wastewater. The reaction wastewater is then discharged into the distribution tank 202 for buffering and stabilization, forming sludge that settles in the lower part of the distribution tank 202 and is composed of suspended solids, colloids, and flocculated flocs, as well as purified water that forms in the upper part of the distribution tank 202. The sludge and purified water are discharged into the flocculation tank 203. The sludge settles in the lower part of the flocculation tank 203, while the purified water is located in the upper part of the flocculation tank 203. The purified water overflows into the overflow tank 204 through the overflow weir 210, and the purified water in the overflow tank 204 is discharged into the storage tank 400 through the pipe 220.

[0042] 3) The sludge is discharged into the filter press 300 through the feed pipe 230. The filter press 300 includes multiple filter plates 301 arranged side by side and moving away from or towards each other. Filter cloths 302 are respectively covered on both sides of the filter plates 301. The two filter cloths 302 on the filter plates 301 surround the filter plates 301 to form a water filtration zone. When the adjacent filter plates 301 are in a state of mutual pressure, the adjacent filter plates 301 surround the filter press zone 303. The filter press zone 303 is located between the two water filtration zones.

[0043] Multiple filter plates 301 are pressed against each other, forming a sealed filter press zone 303 between adjacent filter plates 301. High-pressure gas and sludge are injected into the filter press zone 303 through the feed pipe 230. The sludge is pressed and filtered in the filter press zone 303 to form a sludge cake. The water in the sludge is filtered through the filter cloth 302 and enters the water filtration zone to form filtered clean water. The filtered clean water is discharged into the water storage tank 400 through the pipe 220.

[0044] The aforementioned one-stop green recycling method for purifying and filtering sludge from car wash wastewater in a foundation pit removes particulate matter by passing the wastewater through a five-stage sedimentation system (100). The wastewater is then sequentially reacted with flocculant in a reaction tank (201), causing suspended solids, colloids, and flocculated particles to form sludge. This effectively treats the wastewater into purified water and sludge. The sludge is then filtered through a filter press (300) to form a mud cake and filtered water. Both the filtered and purified water are stored in a storage tank (400). In this way, car wash wastewater is converted into mud cake and clean water through a one-stop purification system. The clean water is used for on-site production, car washing, dust suppression, and road cleaning, resulting in a thorough overall treatment process. This significantly reduces the discharge of sludge wastewater and prevents pollution of municipal pipelines (220) by the wastewater. This invention utilizes purified water for car washing, achieving the recycling of polluted wastewater, cost savings, and a green, environmentally friendly, and pollution-free process.

[0045] Specifically, the flocculant solution is stored in a solution tank, which is connected to the reaction tank 201 by a solution inlet pipe and equipped with a solution suction pump. High-pressure gas is injected into the feed pipe 230 through an air compressor 320.

[0046] Specifically, the filter plate 301 is provided with a water outlet 3010 that connects to the water filtration zone, and the filtered clean water flows into the pipe 220 through the water outlet 3010.

[0047] In construction step 1), multiple sedimentation tanks include a primary sedimentation tank 101, multiple intermediate sedimentation tanks 102, and a terminal sedimentation tank 103. These tanks are arranged side-by-side in sequence. After the car wash wastewater is discharged into the primary sedimentation tank 101, it flows sequentially through the intermediate and terminal sedimentation tanks 102 and 103. Particulate matter in the wastewater settles at the bottom of the primary sedimentation tank 101, the bottom of the intermediate sedimentation tanks 102, and the bottom of the terminal sedimentation tank 103, respectively. The settled wastewater forms at the top of the terminal sedimentation tank 103. Thus, after the car wash wastewater enters the sedimentation tanks, the suspended particles in the wastewater are separated through sedimentation, utilizing the characteristic that the specific gravity of the particles is greater than that of water. To ensure sedimentation effectiveness, this method specifically incorporates a five-stage sedimentation process in addition to the usual three-stage sedimentation tanks. The wastewater after sedimentation is then pumped to a purification system for secondary treatment.

[0048] The car wash pool is connected to the first-end sedimentation tank 101 via a drainage ditch 110. The car wash wastewater in the car wash pool is discharged into the first-end sedimentation tank 101 through the drainage ditch 110. In this way, the car wash wastewater can be directly guided to the sedimentation structure 100 through the drainage ditch 110, achieving efficient purification treatment.

[0049] Specifically, the drainage ditch 110 is also connected to the foundation pit wastewater ditch, so that the wastewater generated in the foundation pit and the car wash wastewater flow into the sedimentation structure 100 together.

[0050] The terminal sedimentation tank 103 is connected to the reaction tank 201 through a connecting pipe, and the connecting pipe is connected to a sedimentation wastewater suction pump, which is installed in the terminal sedimentation tank 103.

[0051] Specifically, in construction step 2), the flocculant solution is formed by mixing polyacrylamide and water. According to the mass ratio, the ratio between polyacrylamide and water is 1:(450-550).

[0052] In construction step 2), a stirrer 2010 is installed in the reaction tank 201. After the sedimented wastewater and flocculant solution are placed in the reaction tank 201, the stirrer 2010 continuously stirs and mixes the sedimented wastewater and flocculant solution. This ensures a complete reaction.

[0053] In construction step 2), the reaction wastewater in reaction tank 201 is kept in a flowing state. The lower part of reaction tank 201 is provided with a reaction connection port. The reaction wastewater in reaction tank 201, which is in a flowing state, is discharged from bottom to top to water distribution tank 202 for buffering and stabilization through the reaction connection port. In this way, the reaction can be guaranteed to be complete in the flowing state. At the same time, the design of water distribution tank 202 is to buffer and stabilize the reaction wastewater, and to prevent the reaction wastewater from entering the flocculation tank 203 at a fast flow rate, which would result in incomplete sedimentation of the reaction wastewater in the flocculation tank 203.

[0054] In construction step 2), the lower part of the water distribution tank 202 is provided with a water distribution connection port, and the sludge and purified water in the water distribution tank 202 are discharged from bottom to top into the flocculation tank 203 through the water distribution connection port;

[0055] The bottom of the flocculation tank 203 is concave downwards, forming multiple concave areas 2030 that are larger at the top and smaller at the bottom. The multiple concave areas 2030 are arranged sequentially along the flow direction of the purified water in the flocculation tank 203, and the tops of adjacent concave areas 2030 are interconnected.

[0056] As the sludge and purified water flow into the flocculation tank 203, the sludge settles in multiple recessed zones 2030 and remains stationary, while the purified water is located at the top of the multiple flocculation tanks 203 and is in a flowing state. This design of multiple recessed zones 2030, which are larger at the top and smaller at the bottom, provides space for settling, allowing the sediment to settle in the recessed zones 2030 and accumulate at the bottom, ensuring thorough purification.

[0057] In construction step 2), the top of the overflow weir 210 extends upwards to form an overflow tip 211. Along the width of the flocculation tank 203, the overflow tip 211 is arranged in multiple curved sections, forming a wave-like pattern. The purified water in the flocculation tank 203 flows over the overflow tip 211 and into the overflow tank 204. In this way, the overflow weir 210 effectively intercepts and retains sludge in the flocculation tank 203, ensuring that only clean, purified water at the top can flow over the weir tip into the overflow tank 204. This helps ensure the quality of the purified water and provides a high-quality water source for subsequent use.

[0058] Next, the overflow tip 211 is arranged in a wave-like pattern, which enhances the structural stability of the weir and increases the overflow area, allowing more purified water to flow smoothly into the overflow pool 204. Furthermore, it slows down the water flow velocity, enabling the purified water to be distributed more evenly as it crosses the weir crest, reducing impact and wear on the weir and extending its service life.

[0059] In this embodiment, a suction pump 310 is provided on the feed pipe 230, and the inner end of the feed pipe 230 is connected to a plurality of recessed areas 2030 respectively; the inner end of the feed pipe 230 has a suction section extending into the recessed area 2030, the suction section extends upward from the bottom of the recessed area 2030 and then bends downward, and the end of the suction section forms an end suction port.

[0060] The suction section has multiple elastic segments 232 made of elastic adhesive layers and multiple hard segments 231 made of hard adhesive layers. The multiple elastic segments 232 and multiple hard segments 231 are arranged at intervals along the length direction of the suction section, and the hard segments 231 are located between two adjacent elastic segments 232. The hard segments 231 are provided with multiple side suction ports 2310, and the multiple side suction ports 2310 are arranged at staggered intervals along the circumference of the hard segments 231.

[0061] In construction step 3), the suction pump uses the feed pipe 230 to draw sludge from the recessed area 2030 via frequency conversion. As the amount of sludge entering the suction section changes, the elastic section 232 undergoes reciprocating expansion and contraction deformation, creating elastic compression and peristalsis on the sludge in the suction section, thus preventing sludge from forming blockages. In this way, the suction section employs an alternating design of elastic and hard rubber layers, ensuring both flexibility and enhanced durability. Multiple side suction ports 2310 on the hard section 231 effectively extract sludge, while the reciprocating expansion and contraction deformation of the elastic section 232 prevents sludge from forming blockages in the suction section. This improves sludge extraction efficiency and reduces the risk of blockages.

[0062] In this embodiment, the end suction port is covered with an elastic mesh layer 233. The outer periphery of the elastic mesh layer 233 is fixedly connected to the suction section. The middle part of the elastic mesh layer 233 is suspended and covers the end suction port, forming an elastic part. The outer side of the elastic part has an outwardly arc-shaped protruding outer mesh layer 234, and the inner side of the elastic part has an inwardly arc-shaped protruding inner mesh layer 235. The outer periphery of the outer mesh layer 234 and the outer periphery of the inner mesh layer 235 are joined together. The middle parts of the outer mesh layer 234 and the middle parts of the inner mesh layer 235 are arranged separately to form an elastic space.

[0063] In construction step 3), the suction pump uses the feed pipe 230 to draw sludge from the recessed area 2030 via frequency conversion. The sludge passes sequentially through the outer convex mesh layer 234, the elastic space, and the inner convex mesh layer 235 before entering the suction section. The outer convex mesh layer 234 and the inner convex mesh layer 235 are compressed by the sludge, exhibiting reciprocating elastic deformation, thus preventing the sludge from clogging the suction port. During the process of the sludge passing through the outer convex mesh layer 234 and the inner convex mesh layer 235, it is elastically compressed by the outer convex mesh layer 234 and the inner convex mesh layer 235, resulting in a dispersed state. In this way, firstly, through the combined design of the outer convex mesh layer 234, the elastic space, and the inner convex mesh layer 235, the sludge passes through these three parts sequentially during the suction process, effectively dispersing the sludge, preventing sludge from clogging the suction port, and increasing the contact area between the sludge and the suction port, thereby improving the suction efficiency.

[0064] Secondly, the elastic deformation characteristics of the outwardly convex mesh layer 234 and the inwardly convex mesh layer 235 can handle sludge of different properties. When the sludge is denser, the outwardly convex mesh layer 234 and the inwardly convex mesh layer 235 are subjected to greater compression, resulting in greater elastic deformation and ensuring that the sludge can pass through smoothly. When the sludge is looser, the elastic deformation of the outwardly convex mesh layer 234 and the inwardly convex mesh layer 235 is relatively smaller, but it can still maintain a certain dispersing effect. This adaptive elastic deformation characteristic makes the suction process more stable and reliable. This improves the operating efficiency of the entire treatment system, reduces downtime caused by blockages, and improves the continuity and stability of the entire treatment system.

[0065] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A one-stop green recycling method for wastewater purification and sludge depressurization in a foundation pit car wash pool, characterized in that: Includes the following steps: 1) The car wash wastewater in the car wash pool is discharged into the sedimentation structure, which has multiple sedimentation tanks arranged in sequence and side by side, and the tops of adjacent sedimentation tanks are interconnected; the car wash wastewater flows through the multiple sedimentation tanks in sequence to form particulate sediments settled at the bottom of the sedimentation tanks and settled wastewater discharged from the sedimentation tanks. 2) The sedimented wastewater is discharged into the purification treatment structure, which includes a reaction tank, a water distribution tank, a flocculation tank and an overflow tank. The reaction tank, water distribution tank, flocculation tank and overflow tank are connected in sequence and arranged side by side. An overflow weir is provided between the flocculation tank and the overflow tank. The sedimentation wastewater and flocculation solution are simultaneously discharged into the reaction tank for stirring and reaction, forming reaction wastewater. The reaction wastewater is then discharged into the distribution tank for buffering and stabilization, forming sludge that settles in the lower part of the distribution tank and is composed of suspended solids, colloids, and flocculated flocs, as well as purified water that forms in the upper part of the distribution tank. The sludge and purified water are then discharged into the flocculation tank, where the sludge settles in the lower part and the purified water is located in the upper part. The purified water overflows into the overflow tank through the overflow weir, and the purified water in the overflow tank is discharged into the storage tank through a pipe. 3) The sludge is discharged into the filter press through the feed pipe. The filter press includes multiple filter plates arranged side by side and moving away from or towards each other. Filter cloth is covered on both sides of each filter plate. The two filter cloths on the filter plate and the filter plate surround each other to form a water filtration zone. When the adjacent filter plates are in a state of mutual pressure, the adjacent filter plates surround each other to form a filtration zone. The filtration zone is located between two water filtration zones. Multiple filter plates are pressed against each other to form a sealed filter press zone between adjacent filter plates. High-pressure gas and sludge are injected into the filter press zone through the feed pipe. The sludge is pressed and filtered in the filter press zone to form a sludge cake. The water in the sludge is filtered through the filter cloth and enters the water filtration zone to form filtered clean water. The filtered clean water is discharged into the water storage tank through the pipe. The feed pipe is equipped with a suction pump, and the inner end of the feed pipe is connected to multiple recessed areas respectively; the inner end of the feed pipe has a suction section extending into the recessed area, the suction section extends upward from the bottom of the recessed area and then bends downward, and the end of the suction section forms an end suction port. The suction section has multiple elastic sections made of elastic adhesive layers and multiple hard sections made of hard adhesive layers. The multiple elastic sections and multiple hard sections are arranged at intervals along the length direction of the suction section, and the hard sections are located between two adjacent elastic sections. The hard sections are provided with multiple side suction ports, and the multiple side suction ports are arranged at staggered intervals along the circumference of the hard sections. In construction step 3), the suction pump uses the feed pipe to draw sludge from the depression area via frequency conversion. As the amount of sludge entering the suction section changes, the elastic section undergoes reciprocating expansion and contraction deformation, forming elastic squeezing and peristalsis on the sludge in the suction section, thus limiting the sludge from forming blockages in the suction section. The end suction port is covered with an elastic mesh layer. The outer periphery of the elastic mesh layer is fixedly connected to the suction section. The middle part of the elastic mesh layer is suspended and covers the end suction port, forming an elastic part. The outer side of the elastic part has an outwardly arc-shaped convex mesh layer, and the inner side of the elastic part has an inwardly arc-shaped convex mesh layer. The outer periphery of the outwardly convex mesh layer and the outer periphery of the inwardly convex mesh layer are joined together. The middle parts of the outwardly convex mesh layer and the middle parts of the inwardly convex mesh layer are arranged separately to form an elastic space. In construction step 3), the suction pump uses a variable frequency drive to suction sludge from the recessed area through the feed pipe. The sludge enters the suction section after passing through the outer convex mesh layer, the elastic space, and the inner convex mesh layer in sequence. The outer and inner convex mesh layers are squeezed by the sludge and undergo reciprocating elastic deformation, which limits the sludge from forming a blockage at the suction port. During the process of the sludge passing through the outer and inner convex mesh layers, it is elastically squeezed by the outer and inner convex mesh layers and dispersed.

2. The one-stop green recycling method for wastewater purification and sludge dewatering in a foundation pit car wash pool as described in claim 1, characterized in that, In construction step 1), the multiple sedimentation tanks include a first sedimentation tank, multiple intermediate sedimentation tanks, and a final sedimentation tank. The first sedimentation tank, multiple intermediate sedimentation tanks, and final sedimentation tanks are arranged side by side in sequence. After the car wash wastewater is discharged into the first sedimentation tank, it flows sequentially along the multiple intermediate sedimentation tanks and the final sedimentation tank. The particulate matter in the car wash wastewater settles in the lower part of the first sedimentation tank, the lower part of the multiple intermediate sedimentation tanks, and the lower part of the final sedimentation tank, respectively. The settled wastewater is formed in the upper part of the final sedimentation tank.

3. The one-stop green recycling method for wastewater purification and sludge dewatering in a foundation pit car wash pool as described in claim 2, characterized in that, The car wash pool is connected to the first sedimentation tank via a drainage ditch, and the car wash wastewater in the car wash pool is discharged into the first sedimentation tank via the drainage ditch.

4. The one-stop green recycling method for wastewater purification and sludge dewatering in a foundation pit car wash pool as described in claim 1, characterized in that, In construction step 2), the flocculant solution is formed by mixing polyacrylamide and water. According to the mass ratio, the ratio between polyacrylamide and water is 1:(450~550).

5. The one-stop green recycling method for wastewater purification and sludge dewatering in a foundation pit car wash pool as described in claim 1, characterized in that, In construction step 2), the reaction tank is equipped with a stirrer. After the precipitated wastewater and flocculant are placed in the reaction tank, the stirrer continuously stirs and mixes the precipitated wastewater and flocculant.

6. The one-stop green recycling method for wastewater purification and sludge dewatering in a foundation pit car wash pool as described in claim 1, characterized in that, In construction step 2), the reaction wastewater in the reaction tank is kept in a flowing state. The lower part of the reaction tank is provided with a reaction connection port. The flowing reaction wastewater in the reaction tank is discharged from bottom to top to the water distribution tank through the reaction connection port for buffering and stabilization.

7. The one-stop green recycling method for wastewater purification and sludge dewatering in a foundation pit car wash pool as described in any one of claims 1 to 6, characterized in that, In construction step 2), the lower part of the water distribution tank is provided with a water distribution connection port, and the sludge and purified water in the water distribution tank are discharged from bottom to top into the flocculation tank through the water distribution connection port. The bottom of the flocculation tank is concave, forming multiple concave areas that are larger at the top and smaller at the bottom. These multiple concave areas are arranged sequentially along the flow direction of the purified water in the flocculation tank, and the tops of adjacent concave areas are interconnected. As the sludge and purified water flow along the flocculation tank, the sludge settles in multiple recessed areas and remains stationary, while the purified water is located at the top of the multiple flocculation tanks and is in a flowing state.

8. The one-stop green recycling method for wastewater purification and sludge dewatering of pit car wash pools as described in any one of claims 1 to 6, characterized in that, In construction step 2), the top of the overflow weir extends upward to form an overflow tip; along the width of the flocculation tank, the overflow tip is arranged in multiple curved sections to form a wave-like arrangement; the purified water in the flocculation tank passes over the overflow tip and enters the overflow tank.

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