Integrated treatment equipment for wastewater, oil separation and air flotation of metro vehicle depot

Abstract

The utility model discloses a subway vehicle depot wastewater oil separation air flotation integrated treatment equipment, and the inner chamber of box is separated into adjusting oil separation chamber, coagulation reaction area, air flotation area, clear water chamber and sludge chamber in proper order, and the front end is connected with the inlet pipe, adjusting oil separation chamber is equipped with oil collecting pipe, inclined pipe filling, and the water overflow goes into the reaction area, coagulation reaction area has stirring subassembly, and air flotation area is equipped with gas dissolving system, reflux pipe and water collecting perforated pipe, and the water collection enters clear water chamber through air flotation outlet pipe, and the upper part of air flotation area is provided with the slag scraper, and the floating dregs are scraped to the collecting groove and are discharged into the sludge chamber. The subway vehicle depot wastewater oil separation air flotation integrated treatment equipment, the inclined pipe filling is high -efficient oil separation, and the coagulation and air flotation are cooperated to remove the dirt, and the oil slick is collected by the liquid level difference, and the power equipment is not needed, and the land occupation, energy consumption and maintenance cost are saved, and the intelligent system is in real time regulation and control, guarantees that the effluent is stable and reaches the standard and part can be reused, solves the problems of traditional equipment process dispersion, high energy consumption and complicated oil slick treatment, and has the environmental protection, energy saving and economic advantages.

Description

Technical Field

[0001] This utility model belongs to the field of wastewater treatment technology, and in particular relates to an integrated oil-water separation and flotation treatment device for wastewater from subway depots. Background Technology

[0002] During subway operation, depots continuously generate large amounts of oily wastewater, primarily from subway car washing wastewater and oily wastewater generated during equipment maintenance. This type of wastewater has a complex composition, containing not only suspended solids and various oily substances (such as lubricating oil and diesel oil), but also potentially heavy metal ions, surfactants, and other pollutants. If discharged directly without effective treatment, the oily substances will form an oil film on the water surface, hindering oxygen exchange between the water and the air, leading to oxygen deprivation and death of aquatic organisms, disrupting the ecological balance, and causing serious pollution to surrounding water bodies, soil, and other ecological environments. It may also cause seepage pollution to groundwater sources, affecting the safety of drinking water for nearby residents.

[0003] Currently, the industry commonly employs a combination of oil-water separation and flotation for the physical treatment of oily wastewater from subways. However, traditional treatment methods often involve separate, independently operating oil-water separation and flotation equipment, which presents significant drawbacks. Firstly, separate equipment requires dedicated installation space and operational access routes. In space-constrained locations like subway depots, site planning is extremely challenging, often resulting in insufficient space or the need to compress other functional areas, increasing the difficulty and cost of site construction planning. Secondly, wastewater must be transferred to the flotation equipment via pipelines after treatment by the oil-water separation equipment. This transfer process prolongs the treatment flow and time, and differences in design parameters (such as treatment volume and flow rate) between different equipment can lead to mismatched process connections, resulting in unstable removal of oil and suspended solids and difficulty in consistently meeting discharge standards.

[0004] Furthermore, the operation and maintenance costs of separate equipment are also relatively high. Not only are the initial purchase costs high for two independent sets of equipment, but subsequent operation also requires significant investment in maintenance (such as parts replacement and regular inspections) and energy consumption (such as electricity consumption by the power systems of both sets). Additionally, dedicated personnel are needed for separate operation and management, significantly increasing labor costs. Moreover, a large number of connecting pipelines are required between the equipment for wastewater transport, making installation complex and posing a risk of leakage at pipeline connections, further increasing the workload of later maintenance and environmental risks. Therefore, developing an integrated treatment device that can solve the above problems has become an urgent need in the field of subway oily wastewater treatment. Utility Model Content

[0005] This utility model provides an integrated oil-water separation and flotation treatment device for wastewater from subway depots, aiming to solve the problems of traditional subway wastewater treatment equipment having a large footprint, dispersed treatment processes, high energy consumption, and high water content in the collected floating oil, requiring additional oil-water separation steps.

[0006] This invention is achieved through an integrated oil-water separation and flotation treatment device for wastewater from subway depots. The tank includes a housing, the inner cavity of which is divided into an oil-water regulating chamber, a reaction chamber, a clear water chamber and a sludge chamber from front to back. The reaction chamber is divided into a coagulation reaction zone and an air flotation zone from front to back. The front end of the housing is connected to a water inlet pipe. An oil collection pipe is installed inside the regulating oil-separating chamber, and the oil collection pipe is connected to the sludge chamber. Inclined tube packing is also installed inside the regulating oil-separating chamber, and the effluent from the regulating oil-separating chamber overflows into the reaction chamber. The coagulation reaction zone is equipped with a stirring assembly, the flotation zone is equipped with a dissolved air system, the flotation zone is equipped with a return pipe, some of the water in the flotation zone enters the dissolved air system through the return pipe, the bottom of the flotation zone is equipped with a water collection perforated pipe, the water collected by the water collection perforated pipe is transported to the clear water chamber through the flotation outlet pipe, and the clear water chamber has a drain outlet on its side wall.

[0007] Preferably, the dissolved air system includes a dissolved air tank, an air compressor, and a reflux pump. The inlet of the reflux pump is connected to the reflux pipe, and the outlet of the reflux pump is connected to the dissolved air tank through a pipeline. The air compressor dissolves high-pressure air into the dissolved air tank, and the dissolved air tank is connected to a release device through a release device pipeline.

[0008] Preferably, a sludge scraper is provided at the upper part of the flotation zone, and a collection tank is also provided in the flotation zone. The sludge scraper scrapes the sludge into the collection tank, and the collection tank is connected to the sludge chamber through a sludge pipe.

[0009] Preferably, it also includes an equipment compartment located on one side of the housing, wherein a dosing device is provided in the equipment compartment, and the dosing device adds chemicals to the coagulation reaction zone through a dosing pipe.

[0010] Beneficial effects Compared with existing technologies, the beneficial effects of this utility model are as follows: This utility model provides an integrated oil-water separation and dissolved air flotation treatment device for wastewater from subway depots. Through a closed-cell structure, it integrates treatment units such as oil separation, coagulation reaction, and dissolved air flotation into one unit. With its rational internal spatial layout and water flow path design, wastewater undergoes pretreatment, core reaction, and deep separation sequentially within the device, eliminating the need for transfer between different units. This significantly shortens the treatment process and avoids the problem of process mismatch at the connection points of separate units, ensuring efficient removal of oil and suspended solids, and guaranteeing stable effluent quality that meets standards, with some indicators even meeting reuse requirements. Simultaneously, the integrated design significantly reduces the overall footprint of the equipment, saving more space compared to traditional separate units. It is suitable for installation scenarios with limited space in subway depots and eliminates the need for numerous connecting pipelines between units, reducing installation complexity and construction costs. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of this utility model.

[0012] In the diagram: 1-Inlet pipe, 2-Regulating oil-water separator, 3-Oil collection pipe, 4-Inclined tube packing, 5-Agitator assembly, 6-Coagulation reaction zone, 7-Air flotation zone, 8-Release device, 9-Dissolved air tank, 10-Air compressor, 11-Recirculation pump, 12-Sludge scraper, 13-Water collection perforated pipe, 14-Air flotation outlet pipe, 15-Air transmission pipeline, 16-Release device pipeline, 17-Recirculation pipe, 18-Sludge pipeline, 19-Clear water chamber, 20-Drain outlet, 21-Sludge chamber, 22-, 23-Dosing device, 24-Dosing pipe, 25-Controller. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model 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 of the present utility model and are not intended to limit the present utility model.

[0014] Please see Figure 1 This utility model provides a technical solution: an integrated oil-water separation and flotation treatment device for wastewater from a subway depot, including a tank. The inner cavity of the tank is divided into an oil-water separation chamber 2, a reaction chamber, a clear water chamber 19, and a sludge chamber 21 from front to back. The reaction chamber is divided into a coagulation reaction zone 6 and a flotation zone 7 from front to back. The front end of the tank is connected to a water inlet pipe 1.

[0015] The housing is made of corrosion-resistant carbon steel, which has good corrosion resistance and sealing performance, effectively preventing wastewater leakage and odor emission; the inclined tube packing 4 is made of PP material, with an inclination angle of 45°-60°, a pipe diameter of 50-80mm, and a length of 1-1.5m. It is fixedly arranged by upper and lower channel steel, which can increase the oil-water separation surface area and improve the oil separation efficiency; the height of the oil collection pipe 3 is adjustable, so as to flexibly adjust the collection position according to the thickness of the floating oil layer, ensuring that the floating oil is efficiently introduced into the sludge chamber 21.

[0016] The height adjustment of the oil collection pipe 3 can be achieved by linking the liquid level sensor with the automatic control module. When the sensor detects a change in the thickness of the floating oil layer, the automatic driving adjustment device adjusts the position of the oil collection pipe 3 so that the oil collection pipe 3 is at the liquid level without manual intervention. The fixed structure design of the inclined tube packing 4 is easy to disassemble. When the inclined tube is blocked or damaged, it can be quickly disassembled and replaced, reducing maintenance difficulty and ensuring the stability of the oil separation function.

[0017] An oil collection pipe 3 is installed inside the regulating oil separator chamber 2, which is connected to the sludge chamber 21. An inclined tube packing 4 is also installed inside the regulating oil separator chamber 2. The effluent from the regulating oil separator chamber 2 overflows into the reaction chamber.

[0018] The oil collection pipe 3 is connected to the sludge pipe 18, which in turn connects to the sludge chamber 21. A telescopic or flexible pipe is provided between the oil collection pipe 3 and the sludge pipe 18 to accommodate the lifting and lowering of the oil collection pipe 3.

[0019] A stirring assembly 5 is installed in the coagulation reaction zone 6, a dissolved air system is installed in the flotation zone 7, a return pipe 17 is installed in the flotation zone 7, some water in the flotation zone 7 enters the dissolved air system through the return pipe 17, a water collection perforated pipe 13 is installed at the bottom of the flotation zone 7, the water collected by the water collection perforated pipe 13 is transported to the clear water chamber 19 through the flotation outlet pipe 14, and a drain outlet 20 is opened on the side wall of the clear water chamber 19.

[0020] Furthermore, the dissolved air system includes a dissolved air tank 9, an air compressor 10, and a return pump 11. The inlet of the return pump 11 is connected to the return pipe 17, and the outlet of the return pump 11 is connected to the dissolved air tank 9 through a pipeline. The air compressor 10 dissolves high-pressure air into the dissolved air tank 9, and the dissolved air tank 9 is connected to a release device 8 through a release device pipe 16.

[0021] When the reflux pump 11 is running, it pressurizes 20%-30% of the treated clean water in the flotation zone 7 to 0.3-0.5MPa and delivers it to the dissolved air tank 9. The air compressor 10 injects air into the dissolved air tank 9 through the air supply pipe 15, and the air-to-water ratio is controlled at 1:5-1:10, so that the air is fully dissolved in the water under pressure to form saturated dissolved air water. The release device 8 is installed at the bottom of the flotation zone 7. When the saturated dissolved air water passes through the release device 8, it is depressurized instantly and releases tiny bubbles with a diameter of 10-30μm. The bubbles can fully adsorb and combine with the flocs in the wastewater.

[0022] Furthermore, a sludge scraper 12 is installed at the upper part of the flotation zone 7, and a collection tank is also installed in the flotation zone 7. The sludge scraper 12 scrapes the sludge into the collection tank, and the collection tank is connected to the sludge chamber 21 through the sludge pipe 18.

[0023] The scum scraper 12 adopts a chain drive, and its operating speed is adjustable. It runs smoothly and has high scum scraping efficiency. After the scum combines with micro air bubbles in the flotation zone 7, it floats to the water surface to form a scum layer. The scum scraper 12 scrapes the scum into the collection tank, and then the scum flows into the sludge chamber 21 by gravity through the sludge pipe 18. The sludge chamber 21 is equipped with an anti-seepage layer to prevent sludge leakage, and the sludge chamber 21 is equipped with a suction port, so that the sludge can be regularly pumped away by a vacuum truck for harmless treatment.

[0024] Furthermore, it also includes an equipment compartment 22 located on one side of the box body, and a dosing device 23 is installed in the equipment compartment 22. The dosing device 23 adds chemicals to the coagulation reaction zone 6 through a dosing pipe 24.

[0025] The dosing device 23 includes a chemical storage tank and a metering pump, which can add coagulant to the coagulation reaction zone 6 according to the coagulation reaction requirements. The dosage is automatically adjusted by the controller 25. The stirring component 5 is a low-speed mixer to ensure that the chemical and wastewater are fully mixed, so that the tiny oil droplets and suspended solids in the wastewater can form stable flocs. The controller 25 is a PLC programmable controller, which can monitor and adjust the water level, water quality such as oil content, suspended solids concentration, flow rate, and dissolved air tank 9 in the oil separator 2, coagulation reaction zone 6, flotation zone 7, and clear water chamber 19 in real time. It can also automatically adjust the operating parameters such as the speed of the slag scraper 12, the dosage of the dosing device 23, and the pressure of the return pump 11 according to the preset program. When the equipment experiences abnormal conditions such as motor overload, excessively high / low water level, or water quality exceeding the standard, the controller 25 can trigger an audible and visual alarm and remotely notify maintenance personnel via SMS or network. At the same time, it can be connected to the subway operation management system to achieve data sharing and remote monitoring.

[0026] The equipment is equipped with a PLC programmable control system, which can monitor key parameters such as water level, water quality, and flow rate in each area in real time. It automatically adjusts operating parameters such as the speed of the sludge scraper, the dosage of the dosing device, and the pressure of the dissolved air system, eliminating the need for continuous manual operation and reducing labor management costs. The dissolved air system uses a partially treated clean water return method to prepare saturated dissolved air water. Combined with a gravity-fed clean water collection and floating oil removal design, it eliminates the need for additional power equipment to drive water flow and floating oil recovery, reducing energy consumption and avoiding daily maintenance costs of power equipment. At the same time, the closed box structure can effectively prevent the emission of wastewater odors and secondary pollution, achieving multiple goals of high-efficiency treatment, space saving, energy saving and cost reduction, and environmental protection.

[0027] The working principle and usage process of this utility model are as follows: After installation, oily wastewater (such as car wash wastewater and equipment maintenance wastewater) generated by the subway depot enters the regulating oil-water separator 2 through the inlet pipe 1. The regulating oil-water separator 2 balances the inlet flow. When the wastewater flows through the inclined tube packing 4, oil droplets gather on the surface of the inclined tube and float to the surface to form a floating oil layer. The floating oil is collected through the adjustable height oil collection pipe 3 and flows into the sludge chamber 21. The wastewater treated by oil separation overflows into the coagulation reaction zone 6. The dosing device 23 adds coagulant to the coagulation reaction zone 6 through the dosing pipe 24. The stirring component 5 starts stirring, causing the tiny oil droplets and suspended solids in the wastewater to form flocs. The wastewater containing flocs flows by gravity into the air flotation zone. 7. The return pump 11 pressurizes and transports the partially treated clean water in the flotation zone 7 to the dissolved air tank 9. The air compressor 10 injects air into the dissolved air tank 9 to form saturated dissolved air water. The saturated dissolved air water is depressurized and released by the release device 8 to release microbubbles. After the bubbles are adsorbed by the flocs, they float to the surface to form a scum layer. The scum scraper 12 scrapes the scum into the collection tank and transports it to the sludge chamber 21 through the sludge pipe 18. The clean water at the bottom of the flotation zone 7 is collected by the water collection perforated pipe 13 and enters the clean water chamber 19 through the flotation outlet pipe 14. The qualified clean water in the clean water chamber 19 is discharged or reused through the drain outlet 20. Throughout the process, the controller 25 monitors the equipment operating parameters in real time and automatically adjusts the operating status to ensure stable and efficient operation of the equipment.

[0028] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An integrated oil-water separation and flotation treatment device for wastewater from subway depots, comprising a housing, characterized in that: The inner cavity of the tank is divided into an oil-water regulating chamber (2), a reaction chamber, a clear water chamber (19) and a sludge chamber (21) from front to back. The reaction chamber is divided into a coagulation reaction zone (6) and an air flotation zone (7) from front to back. The front end of the tank is connected to a water inlet pipe (1). The regulating oil-separating chamber (2) is equipped with an oil collecting pipe (3), which is connected to the sludge chamber (21). The regulating oil-separating chamber (2) is also equipped with inclined tube packing (4), and the effluent from the regulating oil-separating chamber (2) overflows into the reaction chamber. The coagulation reaction zone (6) is equipped with a stirring assembly (5), the flotation zone (7) is equipped with a dissolved air system, the flotation zone (7) is equipped with a return pipe (17), some water in the flotation zone (7) enters the dissolved air system through the return pipe (17), the bottom of the flotation zone (7) is equipped with a water collection perforated pipe (13), the water collected by the water collection perforated pipe (13) is transported to the clear water chamber (19) through the flotation outlet pipe (14), and a drain outlet (20) is provided on the side wall of the clear water chamber (19).

2. The integrated oil-water separation and flotation treatment equipment for subway depot wastewater as described in claim 1, characterized in that: The dissolved air system includes a dissolved air tank (9), an air compressor (10), and a return pump (11). The inlet of the return pump (11) is connected to the return pipe (17), and the outlet of the return pump (11) is connected to the dissolved air tank (9) through a pipeline. The air compressor (10) dissolves high-pressure air into the dissolved air tank (9), and the dissolved air tank (9) is connected to a release device (8) through a release device pipe (16).

3. The integrated oil-water separation and flotation treatment equipment for subway depot wastewater as described in claim 1, characterized in that: A sludge scraper (12) is installed at the upper part of the flotation zone (7). A collection tank is also installed in the flotation zone (7). The sludge scraper (12) scrapes the sludge into the collection tank. The collection tank is connected to the sludge chamber (21) through the sludge pipe (18).

4. The integrated oil-water separation and flotation treatment equipment for subway depot wastewater as described in claim 1, characterized in that: It also includes an equipment compartment (22) located on one side of the box body, and a dosing device (23) is provided in the equipment compartment (22). The dosing device (23) adds chemicals to the coagulation reaction zone (6) through a dosing pipe (24).

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