Integrated device for treating oily sewage

Abstract

The application discloses an integrated treatment device for oily sewage, which comprises a pry-mounted base, and a centrifugal separation device, a gas floatation separation device and a reverse osmosis membrane separation device connected in sequence are installed on the pry-mounted base; the centrifugal separation device is used for centrifugal oil-water separation of the sewage; the gas floatation separation device is used for gas floatation oil-water separation of the sewage subjected to the centrifugal oil-water separation; and the reverse osmosis membrane separation device is used for reverse osmosis oil-water separation of the sewage subjected to the gas floatation oil-water separation; the reverse osmosis membrane separation device comprises a reverse osmosis membrane ultrafiltration part and a reverse osmosis membrane floatation filtration part; a liquid collecting tank is arranged at the bottom of the reverse osmosis membrane ultrafiltration part; the reverse osmosis membrane floatation filtration part floats in the liquid collecting tank; and the reverse osmosis membrane floatation filtration part can perform reverse osmosis filtration on the oil phase floating on the surface layer of the sewage in the liquid collecting tank. The application can integrally perform centrifugal separation, gas floatation separation and reverse osmosis separation on the oily sewage, thereby efficiently separating the oil phase in the oily sewage, and ensuring that the final sewage treatment quality meets the standard.

Description

Technical Field

[0001] This invention relates to the field of oil and gas field wastewater treatment technology, and in particular to an integrated treatment device for oily wastewater. Background Technology

[0002] Wastewater generated during oilfield drilling typically contains over 70% oil, and the oil phase particles are usually smaller than 100 μm, resulting in an emulsified state that makes it difficult to separate the oil phase. Existing technologies, such as Chinese invention patent CN115925204A, disclose an on-site treatment and reinjection system and process for offshore oilfield production water. This system uses centrifugal separation and ultrafiltration to separate the oil phase from the wastewater; however, it suffers from low treatment efficiency or difficulty in meeting environmental emission standards. Furthermore, the various processes and equipment involved in treating oily wastewater in existing technologies are relatively dispersed, further reducing the treatment efficiency. Summary of the Invention

[0003] The purpose of this invention is to overcome the problems of low treatment efficiency, poor treatment effect and low degree of integration of existing oily wastewater treatment devices, and to provide an integrated oily wastewater treatment device.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0005] An integrated oily wastewater treatment device includes a skid-mounted base on which a centrifugal separator, an air flotation separator, and a reverse osmosis membrane separator are sequentially connected. The centrifugal separator is used for centrifugal oil-water separation of wastewater, the air flotation separator is used for air flotation oil-water separation of wastewater that has undergone centrifugal oil-water separation, and the reverse osmosis membrane separator is used for reverse osmosis oil-water separation of wastewater that has undergone air flotation oil-water separation. The reverse osmosis membrane separator includes a reverse osmosis ultrafiltration section and a reverse osmosis floating section. A collection tank is provided at the bottom of the reverse osmosis ultrafiltration section, and the reverse osmosis floating section floats in the collection tank. The reverse osmosis floating section can perform reverse osmosis filtration on the oil phase floating on the surface of the wastewater in the collection tank.

[0006] This invention provides an integrated oily wastewater treatment device. A centrifugal separator, an air flotation separator, and a reverse osmosis membrane separator are modularly and integrated on a skid-mounted base. This facilitates automatic control, makes operation and maintenance more convenient, saves space, and reduces system complexity. This integrated treatment device can continuously and efficiently treat oily wastewater through centrifugal oil-water separation, air flotation oil-water separation, and reverse osmosis oil-water separation. Centrifugal separation removes larger oil particles, air flotation removes small and medium-sized oil droplets, and reverse osmosis membrane separation deeply purifies and removes tiny oil droplets and other residual pollutants. The treatment effect is more thorough, and the purified water quality is higher. It effectively improves the treatment efficiency of oily wastewater while significantly reducing the oil content, ensuring that the treated oily wastewater meets quality standards. The device sets up the reverse osmosis membrane separator as an ultrafiltration section and a flotation section, separating the wastewater into upper and lower layers for treatment. Wastewater treated by ultrafiltration flows into the bottom collection tank. The reverse osmosis membrane floats in the collection tank, which can automatically separate and filter the oil phase floating on the water surface. It makes full use of the buoyancy advantage of oil phase having a lower density than water phase, resulting in better oil-water separation effect.

[0007] Optionally, the reverse osmosis membrane flotation section includes a buoyancy section, a water collection funnel, and a rotating adsorption section. The buoyancy section is disposed outside the water collection funnel and abuts against the outer wall of the water collection funnel. The buoyancy section is used to drive the water collection funnel to float in the collection tank. A first reverse osmosis module is disposed on the side wall of the water collection funnel. The rotating adsorption section is rotatably disposed inside the water collection funnel and is used to adsorb the oil phase.

[0008] This setup utilizes the buoyancy of the buoyancy unit and the water collection funnel to allow the entire floating filter to automatically float on the surface of the collection tank, eliminating the need for external power and resulting in more efficient and energy-saving operation. A first reverse osmosis module is installed on the side wall of the water collection funnel. When wastewater flows into the funnel, it undergoes reverse osmosis filtration through the first reverse osmosis membrane module on the side wall, separating and retaining the oil phase inside the funnel, thus improving the filtration effect. Simultaneously, as the oily wastewater flows into the funnel, it drives the rotating adsorption unit to rotate and adsorb and collect the separated oil phase.

[0009] Optionally, the rotating adsorption unit includes guide fan blades and a rotating motor. The output shaft of the rotating motor is connected to a rotating shaft, which is connected to the guide fan blades. The rotating shaft drives the guide fan blades to rotate around the central axis of the water collecting horn cover. The edge of the guide fan blades away from the central axis of the water collecting horn cover contacts the inner wall of the water collecting horn cover. An adsorption ball is provided at the rotation axis of the guide fan blades. One end of the guide fan blades away from the inner wall of the water collecting horn cover extends to the outside of the adsorption ball, which can adsorb the oil phase.

[0010] This configuration utilizes a rotating motor to drive a rotating shaft, which in turn rotates the guide fan blades. This creates a rotating vortex within the water-collecting funnel, promoting oil-water separation and oil phase enrichment. The rotating vortex also helps break up oil-water emulsions, improving separation efficiency. As the guide fan blades rotate, they first scrape off the oil phase trapped on the inner wall of the water-collecting funnel. The rotation of the guide fan blades then guides the scraped oil phase towards the adsorption balls, where it is adsorbed and fixed.

[0011] Optionally, a detachable oil collection cover is provided at the bottom of the water collection horn cover, and a hollow support extending toward the open end of the water collection horn cover is provided on the oil collection cover. The adsorption ball is rotatably disposed inside the hollow support, and the guide fan blade rotates around the hollow support.

[0012] In this configuration, the oil collection hood is detachably installed at the bottom of the water collection hood. The hollow support has a cavity inside that limits the position of the adsorption balls, and the outer surface of the adsorption balls rotates omnidirectionally with the inner wall of the cavity, allowing for flexible rotation of the adsorption balls within the cavity and more effective collection of the oil phase. The oil collection hood can collect oil that escapes from the adsorption balls, preventing the oil from re-entering the wastewater.

[0013] Optionally, the adsorption ball has an internal cavity, and the surface of the adsorption ball has a plurality of adsorption holes, adsorption grooves or adsorption meshes communicating with the internal cavity. The internal cavity has an oil phase retention section for adsorbing the oil phase.

[0014] This setup creates a porous adsorption structure on the surface of the adsorption ball through adsorption holes, adsorption tanks, or adsorption nets, greatly increasing the adsorption surface area accessible to the oil phase. This allows for more effective capture and adsorption of the oil phase. Furthermore, the oil phase is further stabilized and adsorbed through the oil phase retention section inside the adsorption ball, effectively reducing the oil content of oily wastewater.

[0015] Optionally, the oil phase retention portion is an oleophilic adsorption substrate.

[0016] By using this configuration, the oil phase retention section is set as an oleophilic adsorption substrate, such as sawdust or oil-absorbing cotton shavings, which further enhances the adsorption capacity of the adsorption ball for the oil phase.

[0017] Optionally, the reverse osmosis membrane ultrafiltration section includes a tank, the bottom of which is connected to the collection tank; the upper part of the tank is configured as a water collection section, and a stirring device is installed in the water collection section to stir the liquid in the water collection section; the water collection section is connected to the reverse osmosis filter cartridge through a first pipeline, and a second reverse osmosis module is installed in the reverse osmosis filter cartridge for reverse osmosis filtration of wastewater; the reverse osmosis filter cartridge is connected to the water distribution section through a second pipeline, and the water distribution section is connected to the collection tank through a third pipeline, and the water distribution section is also connected to the reverse osmosis filter cartridge through a fourth pipeline, the fourth pipeline being equipped with a backwash pump; the water collection section is provided with a first liquid inlet, which is connected to the air flotation separator; the collection tank is provided with a first liquid outlet.

[0018] In this configuration, oily wastewater from the air flotation separator enters the water collection section through the first inlet, and the oily wastewater in the water collection section is stirred by a stirring device installed in the water collection section, so that the oil phase molecules and water phase molecules are evenly distributed. The stirred oily wastewater enters the reverse osmosis filter cartridge and undergoes reverse osmosis filtration through the second reverse osmosis module inside the cartridge. This process traps the oil phase within the filter cartridge. The de-oiled wastewater then flows through the outlet of the filter cartridge and a second pipeline to the water distribution section. This section divides the wastewater into two parts. One part flows through a third pipeline to a collection tank, where the aqueous phase, separated by the reverse osmosis membrane flotation section, flows out through the first outlet, for example, into a storage tank. The other part flows back to the reverse osmosis filter cartridge under the action of a backwash pump on a fourth pipeline to backwash the cartridge. The oil phase trapped inside the filter cartridge is discharged through the oil phase discharge pipe on the filter cartridge during backwashing, thus extending the service life of the second reverse osmosis membrane module.

[0019] Optionally, the bottom of the water collection section has a funnel-shaped structure.

[0020] With this design, the funnel-shaped bottom structure facilitates the accumulation of liquid towards the center, which in turn helps to draw the liquid out of the collection section through the first pipe, making it easier for subsequent filtration steps to be carried out.

[0021] Optionally, the air flotation separation device includes an air flotation tank, a bubbler is provided at the bottom of the air flotation tank, and an isolation net is provided inside the air flotation tank to divide the interior of the air flotation tank into a top oleophobic part and a bottom oleophilic part. An oil-water separation net is provided in the bottom oleophilic part. A second liquid inlet is provided in the bottom oleophilic part, and the second liquid inlet is connected to the centrifugal separation device. A second liquid outlet is provided in the top oleophobic part, and the second liquid outlet is connected to the reverse osmosis membrane separation device.

[0022] In this configuration, the aqueous phase from the centrifugal separator enters the flotation tank through the second inlet and flows upward under the buoyancy provided by the bubbler. This allows the oily wastewater to pass through the oil-water separation screen, thus separating the oil phase. Simultaneously, a separation screen traps the separated oil phase in the oleophilic separation section, while the separated aqueous phase passes through the screen into the oleophobic separation section. The separated aqueous phase then exits through the second outlet into the reverse osmosis membrane separation unit for further treatment.

[0023] Optionally, the oil-water separation mesh is stacked at an angle.

[0024] This setup, which involves stacking oil-water separation nets at an angle, effectively increases the contact area between the nets and the oily wastewater, thereby improving the oil-water separation efficiency and effect.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] 1. This invention provides an integrated oily wastewater treatment device. A centrifugal separator, an air flotation separator, and a reverse osmosis membrane separator are modularly and integrated on a skid-mounted base. This facilitates automatic control, makes operation and maintenance more convenient, saves space, and reduces system complexity. This integrated treatment device can continuously and efficiently treat oily wastewater through centrifugal oil-water separation, air flotation oil-water separation, and reverse osmosis oil-water separation. Centrifugal separation removes larger oil particles, air flotation removes small and medium-sized oil droplets, and reverse osmosis membrane separation deeply purifies and removes tiny oil droplets and other residual pollutants. The treatment effect is more thorough, and the purified water quality is higher. It effectively improves the treatment efficiency of oily wastewater while significantly reducing the oil content, ensuring that the treated oily wastewater meets quality standards. This device sets the reverse osmosis membrane separator as an ultrafiltration section and a flotation section, separating the wastewater into upper and lower layers for treatment. Wastewater treated by ultrafiltration flows into the bottom collection tank. The reverse osmosis membrane floats in the collection tank, which can automatically separate and filter the oil phase floating on the water surface. It makes full use of the buoyancy advantage of oil phase having a lower density than water phase, resulting in better oil-water separation effect.

[0027] 2. The integrated oily wastewater treatment device provided by this invention utilizes the buoyancy of the buoyancy unit and the water collection funnel to allow the entire floating filter to automatically float on the surface of the collection tank without the need for external power, resulting in more efficient and energy-saving operation. A first reverse osmosis module is installed on the side wall of the water collection funnel. When wastewater flows into the interior of the water collection funnel, it undergoes reverse osmosis filtration through the first reverse osmosis membrane module on the side wall of the water collection funnel, causing the oil phase to separate and be trapped inside the water collection funnel, thus improving the filtration effect. At the same time, when the oily wastewater flows into the interior of the water collection funnel, it drives the rotating adsorption unit to rotate to adsorb and collect the separated oil phase.

[0028] 3. The integrated oily wastewater treatment device provided by this invention can drive a rotating shaft to rotate via a rotating motor, which in turn drives the guide fan blades to rotate. A rotating vortex is formed inside the water collection funnel, promoting oil-water separation and oil phase enrichment. The rotating vortex also helps to break the oil-water emulsion state, improving separation efficiency. When the guide fan blades rotate, the oil phase trapped on the inner wall of the water collection funnel is first scraped off, and guided by the rotation of the guide fan blades, the scraped oil phase flows along the guide fan blades to the adsorption balls, where it is then adsorbed and fixed.

[0029] 4. The present invention provides an integrated treatment device for oily wastewater. The oily wastewater from the air flotation separation device enters the water collection section through the first inlet, and the oily wastewater in the water collection section is stirred by the stirring device installed in the water collection section, so that the oil phase molecules and water phase molecules are evenly distributed. The stirred oily wastewater enters the reverse osmosis filter cartridge and undergoes reverse osmosis filtration through the second reverse osmosis module inside the cartridge. This process traps the oil phase within the filter cartridge. The de-oiled wastewater then flows through the outlet of the filter cartridge and a second pipeline to the water distribution section. This section divides the wastewater into two parts. One part flows through a third pipeline to a collection tank, where the aqueous phase, separated by the reverse osmosis membrane flotation section, flows out through the first outlet, for example, into a storage tank. The other part flows back to the reverse osmosis filter cartridge under the action of a backwash pump on a fourth pipeline to backwash the cartridge. The oil phase trapped inside the filter cartridge is discharged through the oil phase discharge pipe on the filter cartridge during backwashing, thus extending the service life of the second reverse osmosis membrane module. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall structure of an integrated oily wastewater treatment device.

[0031] Figure 2 This is a schematic diagram of a reverse osmosis membrane separation device.

[0032] Figure 3 This is a schematic diagram of the reverse osmosis membrane float filter section.

[0033] Figure 4 for Figure 3 Sectional view along axis AA;

[0034] Figure 5 This is a schematic diagram of an air flotation separation device.

[0035] Reference numerals: 1-Skid-mounted base, 2-Centrifugal separator, 21-Cable fittings, 3-Air flotation separator, 301-Second inlet, 302-Second outlet, 31-Air flotation tank, 311-Top oleophobic section, 312-Bottom oleophilic section, 32-Bubble generator, 33-Separation screen, 34-Oil-water separator screen, 4-Reverse osmosis membrane separator, 401-First inlet, 402-First outlet, 41-Reverse osmosis ultrafiltration section, 411-Tank body, 4111-First pipeline, 411 2-Second pipeline, 4113-Third pipeline, 4114-Fourth pipeline, 412-Water collection section, 413-Stirring device, 414-Reverse osmosis filter cartridge, 415-Water distribution section, 416-Backwash pump, 42-Reverse osmosis membrane flotation section, 421-Buoyancy section, 422-Water collection horn cover, 4221-First reverse osmosis module, 423-Guide fan blade, 424-Adsorption ball, 425-Rotating shaft, 426-Rotating motor, 427-Oil collection cover, 428-Hollow support, 43-Liquid collection tank. Detailed Implementation

[0036] The present invention will be further described in detail below with reference to experimental examples and specific embodiments. However, this should not be construed as limiting the scope of the above-mentioned subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0037] Unless otherwise specified, the use of terms such as "upper," "lower," "left," "right," "center," "inner," and "outer" to indicate orientation or positional relationships in the description of specific embodiments of the present invention is based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is typically placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0038] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," and "parallel" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, or parallel, but rather that it can be slightly tilted or have a deviation. For example, "horizontal" merely means that its direction is more horizontal relative to "vertical," not that the structure must be completely horizontal, but that it can be slightly tilted. Alternatively, it can be simplified to mean that the corresponding device / component / element, when set in a "horizontal," "vertical," "suspended," or "parallel" direction, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the present invention.

[0039] Furthermore, the use of terms such as "first," "second," "third," etc. in terminology is merely for distinguishing identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0040] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as 2, 3, 4, 5, 6, 7, 8, or 9, and can even exceed nine.

[0041] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to common connection methods in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0042] Definitions of abbreviations and key terms:

[0043] (1) Reverse osmosis membrane: In the natural osmosis process, the solvent diffuses from the low concentration to the high concentration part through the osmosis membrane; while reverse osmosis refers to the diffusion of the solvent in the concentrated solution through the membrane to the dilute solution under the action of external pressure. The semi-permeable membrane with this function is called reverse osmosis membrane, also known as RO (Reverse Osmoses) membrane.

[0044] Example 1

[0045] like Figures 1-4 As shown, an integrated oily wastewater treatment device includes a skid-mounted base 1, such as... Figure 1As shown, the skid-mounted base 1 can be integrated and installed from left to right with a centrifugal separation device 2, an air flotation separation device 3, and a reverse osmosis membrane separation device 4 connected in sequence.

[0046] Centrifugal separator 2 is used for centrifugal oil-water separation of wastewater. Centrifugal separator 2 can use a commonly used industrial centrifuge, which operates on the principle of utilizing the density difference between oil and water, as well as centrifugal force. When the oil-water mixture enters the centrifugal separator, because the density of oil is generally less than that of water, the oil floats on the water surface, forming a thin film. Inside the separator, there is a high-speed rotating cylinder. The centrifugal force generated by this rotation separates the oil and water according to their density difference. Specifically, centrifugal separator 2 can include a centrifugal oil phase section and a centrifugal water phase section. The outlet of the centrifugal water phase section can be connected to the inlet of the air flotation separator 3.

[0047] The air flotation separator 3 is used to further separate the wastewater from the centrifugal oil-water separation using air flotation. The outlet of the air flotation separator 3 can be connected to the inlet of the reverse osmosis membrane separator 4. The reverse osmosis membrane separator 4 is used to further separate the wastewater from the air flotation oil-water separation using reverse osmosis.

[0048] Specific examples Figure 2 As shown, the reverse osmosis membrane separation device 4 includes a reverse osmosis ultrafiltration section 41 and a reverse osmosis membrane flotation section 42. A collection tank 43 is provided at the bottom of the reverse osmosis ultrafiltration section 41, and the reverse osmosis membrane flotation section 42 floats within the collection tank 43. The reverse osmosis membrane flotation section 42 can perform reverse osmosis filtration on the oil phase floating on the surface of the wastewater within the collection tank 43. In this embodiment, the reverse osmosis ultrafiltration section 41 is located above the reverse osmosis membrane flotation section 42, meaning that the wastewater entering the reverse osmosis membrane separation device 4 first passes through the reverse osmosis ultrafiltration section 41 and then through the reverse osmosis membrane flotation section 42.

[0049] Specifically, such as Figure 2 As shown, the reverse osmosis membrane ultrafiltration unit 41 includes a tank 411, the bottom of which is connected to the collection tank 43.

[0050] The upper part of the tank 411 is configured as a water collection section 412, and the water collection section 412 is provided with a first liquid inlet 401, which is connected to the air flotation separator 3. Wastewater treated by the air flotation separator 3 enters the water collection section 412 through the first liquid inlet 401.

[0051] A stirring device 413 is installed inside the water collection section 412. The stirring device 413 is used to stir the liquid inside the water collection section 412.

[0052] The water collection section 412 is connected to the reverse osmosis filter cartridge 414 via the first pipe 4111, such as Figure 2As shown, the bottom of the water collection section 412 can be configured as a funnel-shaped structure, which facilitates the accumulation of liquid towards the center and allows the liquid in the water collection section 412 to be drawn out through the first pipe 4111, thus facilitating subsequent filtration steps.

[0053] A second reverse osmosis module is installed inside the reverse osmosis filter cartridge 414. The reverse osmosis filter cartridge 414 is used for reverse osmosis filtration of wastewater. Here, the second reverse osmosis module can use a reverse osmosis membrane or an ultrafiltration membrane. The micropore diameter of the ultrafiltration membrane can be controlled below 0.01μm, that is, it can separate fine suspended solids, tiny oil particles, colloids, etc. with a particle size >0.01μm in wastewater. The ultrafiltration membrane material can be commonly used in industry, such as polyceramic membranes, ceramic membranes, polyvinylidene fluoride (PVDF), polyethersulfone (PES), polypropylene (PP), polyethylene (PE), polysulfone (PS), polyacrylonitrile (PAN), etc.

[0054] After the reverse osmosis filter cartridge 414 performs primary filtration on the oily wastewater, the oil phase in the oily wastewater is trapped inside the reverse osmosis filter cartridge 414. The deoiled oily wastewater flows through the outlet of the reverse osmosis filter cartridge 414 and through the second pipeline 4112 to the water distribution section 415, which divides the oily wastewater into two parts.

[0055] Specifically, the water distribution section 415 is connected to the collection tank 43 through the third pipeline 4113. The water distribution section 415 is also connected to the reverse osmosis filter cartridge 414 through the fourth pipeline 4114. The fourth pipeline 4114 is equipped with a backwash pump 416, which backwashes the sewage flowing into the fourth pipeline 4114 back to the reverse osmosis filter cartridge 414.

[0056] The collection tank 43 is provided with a first outlet 402, through which the wastewater treated by the reverse osmosis membrane flotation section 42 in the collection tank 43 is discharged.

[0057] In this configuration, oily wastewater from the air flotation separator 3 enters the water collection section 412 through the first inlet 401. The oily wastewater in the water collection section 412 is stirred by the stirring device 413, ensuring a uniform distribution of oil and water phase molecules. The stirred oily wastewater then enters the reverse osmosis filter cartridge 414, where it is filtered by the second reverse osmosis module. This filters the oil phase within the filter cartridge 414, trapping it. The de-oiled wastewater then flows through the outlet of the reverse osmosis filter cartridge 414 and through the second pipeline 4112 to the water distribution section 415, which can be understood as a water separator commonly used in industry.

[0058] The water separation section 415 divides the oily wastewater into two parts. One part of the oily wastewater flows to the collection tank 43 through the third pipeline 4113. The water phase separated by the reverse osmosis membrane flotation section 42 in the collection tank 43 flows out through the first outlet 402, for example, into a water storage tank. The other part of the oily wastewater flows back to the reverse osmosis filter cartridge 414 under the action of the backwash pump 416 on the fourth pipeline 4114 to backwash the inside of the reverse osmosis filter cartridge 414. The oil phase trapped inside the reverse osmosis filter cartridge 414 is discharged through the oil phase discharge pipe (not shown in the figure) on the reverse osmosis filter cartridge 414 under the action of backwashing, thereby extending the service life of the second reverse osmosis membrane module.

[0059] The integrated oily wastewater treatment device provided in this embodiment modularly and integrally integrates a centrifugal separator 2, an air flotation separator 3, and a reverse osmosis membrane separator 4 on a skid-mounted base 1. This facilitates automatic control, makes operation and maintenance more convenient, saves space, and reduces system complexity. This integrated treatment device can continuously and efficiently perform centrifugal oil-water separation, air flotation oil-water separation, and reverse osmosis oil-water separation on oily wastewater. Centrifugal separation can remove larger oil particles, air flotation separation can remove small and medium-sized oil droplets, and reverse osmosis membrane separation can deeply purify and remove tiny oil droplets and other residual pollutants. The treatment effect is more thorough, the purified water quality is higher, and the treatment efficiency of oily wastewater is effectively improved. At the same time, it can greatly reduce the oil content of oily wastewater, ensuring that the oily wastewater treatment quality meets the standards. This device sets the reverse osmosis membrane separator 4 as an ultrafiltration section and a flotation section, separating the wastewater into upper and lower layers for treatment. Wastewater treated by ultrafiltration flows into the bottom collection tank 43. The reverse osmosis membrane floating filter 42 is designed to float in the collection tank 43, which can automatically perform reverse osmosis separation and filtration of the oil phase floating on the water surface. It makes full use of the buoyancy advantage of oil phase having a lower density than water phase, resulting in better oil-water separation effect.

[0060] Example 2

[0061] Based on Example 1, the reverse osmosis membrane flotation unit 42 in this embodiment includes a buoyancy unit 421, a water collection horn cover 422, and a rotating adsorption unit. The buoyancy unit 421 is disposed outside the water collection horn cover 422 and abuts against the outer wall of the water collection horn cover 422. The buoyancy unit 421 is used to drive the water collection horn cover 422 to float in the collection tank 43; specifically, as shown... Figure 3 As shown, the buoyancy part 421 can be configured as a hollow spherical or near-spherical structure, that is, it can use a buoyancy airbag. The inner cavity of the spherical shell is closed to form a hollow structure. The outer shell can be injection molded or blow molded from engineering plastics such as polypropylene (PP) or high-density polyethylene (HDPE). These materials have good corrosion resistance, processability, and cost performance.

[0062] like Figure 3As shown, the buoyancy part 421 can be specifically set at the lower part of the outward-turned edge of the water collection horn cover 422. The outward-turned edge of the water collection horn cover 422 forms a large annular support surface, and the buoyancy part 421 is located directly below it, which can provide a stable support force for the water collection horn cover 422 and prevent tilting or displacement.

[0063] The side wall of the water collection horn cover 422 is provided with a first reverse osmosis module 4221. Specifically, the first reverse osmosis module 4221 can use a reverse osmosis membrane with a pore size of 0.0004μm-0.001μm. The reverse osmosis membrane model can be ULP31-4040, and the reverse osmosis membrane material can be cellulose acetate (CA) or polyamide (PA), etc.

[0064] The water collection horn cover 422 has a rotating adsorption section inside, which is used to adsorb the oil phase.

[0065] The buoyancy unit 421 provides buoyancy to the water collecting horn cover 422, causing it to float on the surface of the liquid in the collection tank 43. The top opening of the water collecting horn cover 422 is submerged below the liquid surface, allowing oily wastewater to flow into it. After the oily wastewater flows into the interior of the water collecting horn cover 422, it undergoes reverse osmosis filtration through the first reverse osmosis module 4221 on the inner wall of the water collecting horn cover 422. This separates the oil phase, trapping it inside the water collecting horn cover 422. Simultaneously, as the oily wastewater flows into the interior of the water collecting horn cover 422, it drives the rotating adsorption unit to rotate, adsorbing and collecting the separated oil phase.

[0066] Example 3

[0067] like Figure 3 , Figure 4 As shown, based on Embodiment 2, to further improve the rotational adsorption effect of the rotary adsorption unit, in this embodiment, the rotary adsorption unit may include a guide fan blade 423 and a rotating motor 426. The output shaft of the rotating motor 426 is connected to a rotating shaft 425. The rotating shaft 425 is connected to the guide fan blade 423. The rotating shaft 425 drives the guide fan blade 423 to rotate around the central axis of the water collecting horn cover 422. The edge of the guide fan blade 423 away from the central axis of the water collecting horn cover 422 contacts the inner wall of the water collecting horn cover 422. An adsorption ball 424 is provided at the rotation axis of the guide fan blade 423. One end of the guide fan blade 423 away from the inner wall of the water collecting horn cover 422 extends to the outside of the adsorption ball 424. The adsorption ball 424 can adsorb the oil phase.

[0068] In this configuration, the rotating motor 426 drives the rotating shaft 425 to rotate, which in turn drives the guide fan blades 423 to rotate. This creates a rotating vortex within the water collection funnel shroud 422, promoting oil-water separation and oil phase enrichment. The rotating vortex also helps break up the oil-water emulsion state, improving separation efficiency.

[0069] When the guide fan blade 423 rotates, it first scrapes off the oil phase trapped on the inner wall of the water collecting horn cover 422. Then, through the rotation of the guide fan blade 423, the scraped oil phase can flow along the guide fan blade 423 to the adsorption ball 424, and then the oil level is adsorbed and fixed by the adsorption ball 424.

[0070] Furthermore, a detachable oil collection cover 427 is provided at the bottom of the water collection horn cover 422, and a hollow support 428 is provided at the top of the oil collection cover 427 extending toward the open end of the water collection horn cover 422. The hollow support 428 extends into the interior of the water collection horn cover 422, and the adsorption ball 424 is rotatably disposed inside the hollow support 428. The guide fan blade 423 can rotate around the hollow support 428 through a rotating bearing.

[0071] With this configuration, the oil collection hood 427 is detachably installed at the bottom of the water collection horn cover 422. The hollow support 428 has a cavity inside that limits the position of the adsorption ball 424, and the outer surface of the adsorption ball 424 rotates omnidirectionally with the inner wall of the cavity, allowing for flexible rotation of the adsorption ball 424 within the cavity and achieving more effective collection of the oil phase. The oil collection hood 427 can collect oil phase escaping from the adsorption ball 424, preventing the oil phase from re-integrating into the wastewater.

[0072] Specifically, a ball bearing can be provided on the outer spherical surface of the adsorption ball 424, and the ball bearing makes rolling contact with the inner wall of the hollow cavity of the hollow support 428.

[0073] Furthermore, the adsorption ball 424 has an internal cavity, and its surface has several adsorption holes, adsorption grooves, or adsorption meshes communicating with the internal cavity. An oil phase retention section is provided within the internal cavity of the adsorption ball 424, which is used to adsorb the oil phase. Specifically, the oil phase retention section is an oleophilic adsorption substrate.

[0074] This configuration creates a porous adsorption structure on the surface of the adsorption ball 424 through adsorption holes, adsorption grooves, or adsorption mesh, significantly increasing the adsorption surface area accessible to the oil phase. This allows for more effective capture and adsorption of the oil phase. The oil phase is further stabilized and adsorbed by the oil phase retention section within the inner cavity of the adsorption ball 424, effectively reducing the oil content of the oily wastewater. The oil phase retention section includes at least one oleophilic adsorption substrate disposed within the inner cavity. For example, the oil phase retention section can be configured to include at least one oleophilic adsorption substrate containing built-in sawdust or oil-absorbing cotton.

[0075] Example 4

[0076] Based on Example 3, such as Figure 5 As shown, the air flotation separation device 3 of this embodiment includes an air flotation tank 31, a bubbler 32 is provided at the bottom of the air flotation tank 31, and an isolation net 33 is provided inside the air flotation tank 31. The isolation net 33 divides the interior of the air flotation tank 31 into a top oleophobic part 311 and a bottom oleophilic part 312. An oil-water separation net 34 is provided in the bottom oleophilic part 312.

[0077] like Figure 5 As shown, a second inlet 301 is provided on one side of the bottom oleophilic section 312. The aqueous phase from the centrifugal separator 2 enters the flotation tank 31 through the second inlet 301 and flows upward under the upward buoyancy provided by the aerator 32, allowing the oily wastewater to pass through the oil-water separation screen 34, thereby separating the oil phase. At the same time, by setting the isolation screen 33, the separated oil phase is retained in the bottom oleophilic section 312, while the separated aqueous phase passes through the isolation screen 33 and enters the top oleophobic section 311. A second outlet 302 is provided on one side of the top oleophobic section 311, and the separated aqueous phase enters the reverse osmosis membrane separation device 4 through the second outlet 302 for subsequent treatment.

[0078] Furthermore, the oil-water separator 34 is arranged in an inclined stacked configuration, i.e. Figure 5 As shown, the oil-water separation mesh 34 forms a certain angle with the horizontal plane, and multiple layers of oil-water separation mesh 34 are stacked. By stacking the oil-water separation mesh 34 at an angle, the contact area between the oil-water separation mesh 34 and the oily wastewater can be effectively increased, thereby improving the oil-water separation efficiency and effect. Specifically, the oil-water separation mesh 34 can be the NITI-200 oil-water separation filter mesh made of stainless steel.

[0079] When using the integrated oily wastewater treatment device provided in this embodiment, the centrifugal separator 2, the air flotation separator 3, and the reverse osmosis membrane separator 4 are modularly integrated and installed on the skid-mounted base 1. The oily wastewater first enters the centrifugal separator 2, where it is centrifuged. Due to the higher specific gravity of the oil phase, the centrifugal force provided by the centrifugal separator 2 separates the oil phase from the water phase in the oily wastewater, thereby reducing the oil content in the wastewater to below 40%. The separated oil phase is discharged through the centrifugal oil phase section of the centrifugal separator 2 to an oil collection tank for storage, avoiding pollution of the external environment. The separated water phase then enters the air flotation separator 3 after passing through the centrifugal water phase section of the centrifugal separator 2. Here, the water phase refers to the wastewater that still contains the oil phase after centrifugation.

[0080] The air flotation separator 3 is used for oil-water separation of oily wastewater. Air bubbles are introduced into the oily wastewater through the bubbler 32, causing it to churn and pass through the bottom oleophilic section 312 and the top oleophobic section 311. The bottom oleophilic section 312 traps the oil phase, while the top oleophobic section 311 allows the water phase to pass through, thus retaining the oil phase within the air flotation separator 3. This further reduces the oil content of the oily wastewater to below 10%-15%. The separated water phase then continues into the reverse osmosis membrane separator 4. Here, the water phase refers to the wastewater that still contains the oil phase after air flotation separation.

[0081] Oily wastewater first enters the reverse osmosis membrane ultrafiltration section 41 in the reverse osmosis membrane separation device 4. The oily wastewater undergoes primary filtration through the reverse osmosis membrane ultrafiltration section 41, where the oil phase is retained, further reducing the oil content in the wastewater to 5%-8%. The oily wastewater after primary filtration further enters the collection tank 43, where it undergoes secondary reverse osmosis filtration through the reverse osmosis membrane flotation section 42 floating on the surface of the wastewater. The oil phase is retained in the reverse osmosis membrane flotation section 42, further reducing the oil content in the wastewater to below 5%.

[0082] The above are merely preferred embodiments of the present invention and are 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. An integrated oily wastewater treatment device, comprising a skid-mounted base (1), characterized in that, The skid-mounted base (1) is equipped with a centrifugal separation device (2), an air flotation separation device (3), and a reverse osmosis membrane separation device (4) connected in sequence. The centrifugal separation device (2) is used to separate oil and water in sewage by centrifugation, the air flotation separation device (3) is used to separate oil and water in sewage that has undergone centrifugal oil and water separation by air flotation, and the reverse osmosis membrane separation device (4) is used to separate oil and water in sewage that has undergone air flotation oil and water separation by reverse osmosis. The reverse osmosis membrane separation device (4) includes a reverse osmosis membrane ultrafiltration section (41) and a reverse osmosis membrane flotation section (42). The bottom of the reverse osmosis membrane ultrafiltration section (41) is provided with a collection tank (43). The reverse osmosis membrane flotation section (42) floats in the collection tank (43). The reverse osmosis membrane flotation section (42) can perform reverse osmosis filtration on the oil phase floating on the surface of the sewage in the collection tank (43). The reverse osmosis membrane flotation unit (42) includes a buoyancy unit (421), a water collection horn cover (422), and a rotating adsorption unit. The buoyancy unit (421) is disposed outside the water collection horn cover (422) and abuts against the outer wall of the water collection horn cover (422). The buoyancy unit (421) is used to drive the water collection horn cover (422) to float in the liquid collection tank (43). The side wall of the water collection horn cover (422) is provided with a first reverse osmosis module (4221). The rotating adsorption section is rotatably arranged inside the water collection horn cover (422), and the rotating adsorption section is used to adsorb the oil phase.

2. The integrated oily wastewater treatment device according to claim 1, characterized in that, The rotating adsorption unit includes a guide fan blade (423) and a rotating motor (426). The output shaft of the rotating motor (426) is connected to the rotating shaft (425). The rotating shaft (425) is connected to the guide fan blade (423). The rotating shaft (425) drives the guide fan blade (423) to rotate around the central axis of the water collecting horn cover (422). The edge of the guide fan blade (423) away from the central axis of the water collecting horn cover (422) contacts the inner wall of the water collecting horn cover (422); An adsorption ball (424) is provided at the rotation axis of the guide fan blade (423). One end of the guide fan blade (423) away from the inner wall of the water collection horn cover (422) extends to the outside of the adsorption ball (424). The adsorption ball (424) can adsorb the oil phase.

3. The integrated oily wastewater treatment device according to claim 2, characterized in that, The bottom of the water collecting horn cover (422) is provided with a detachable oil collecting cover (427). The oil collecting cover (427) is provided with a hollow support (428) extending toward the open end of the water collecting horn cover (422). The adsorption ball (424) is omnidirectionally rotatably disposed inside the hollow support (428). The guide fan blade (423) rotates around the hollow support (428).

4. The integrated oily wastewater treatment device according to claim 2, characterized in that, The adsorption ball (424) has an internal cavity, and the surface of the adsorption ball (424) is provided with a plurality of adsorption holes, adsorption grooves or adsorption nets communicating with the internal cavity. The internal cavity is provided with an oil phase retention part, which is used to adsorb the oil phase.

5. The integrated oily wastewater treatment device according to claim 4, characterized in that, The oil phase retention section is an oleophilic adsorption substrate.

6. The integrated oily wastewater treatment device according to claim 1, characterized in that, The reverse osmosis membrane ultrafiltration unit (41) includes a tank (411), the bottom of which is connected to the collection tank (43); The upper part of the tank (411) is configured as a water collection section (412), and a stirring device (413) is provided in the water collection section (412) for stirring the liquid in the water collection section (412). The water collection section (412) is connected to the reverse osmosis filter cartridge (414) through the first pipeline (4111). The reverse osmosis filter cartridge (414) is equipped with a second reverse osmosis module and is used to perform reverse osmosis filtration on sewage. The reverse osmosis filter cartridge (414) is connected to the water distribution section (415) through the second pipeline (4112), the water distribution section (415) is connected to the liquid collection tank (43) through the third pipeline (4113), the water distribution section (415) is also connected to the reverse osmosis filter cartridge (414) through the fourth pipeline (4114), and the fourth pipeline (4114) is equipped with a backwash pump (416). The water collection section (412) is provided with a first liquid inlet (401), which is connected to the air flotation separator (3); the liquid collection tank (43) is provided with a first liquid outlet (402).

7. The integrated oily wastewater treatment device according to claim 6, characterized in that, The bottom of the water collection section (412) has a funnel-shaped structure.

8. The integrated oily wastewater treatment device according to claim 1, characterized in that, The air flotation separation device (3) includes an air flotation tank (31), a bubbler (32) is provided at the bottom of the air flotation tank (31), and an isolation net (33) is provided inside the air flotation tank (31). The isolation net (33) divides the interior of the air flotation tank (31) into a top oleophobic part (311) and a bottom oleophilic part (312). An oil-water separation net (34) is provided in the bottom oleophilic part (312). The bottom oleophilic part (312) is provided with a second liquid inlet (301), and the second liquid inlet (301) is connected to the centrifugal separation device (2); The top oleophobic section (311) is provided with a second liquid outlet (302), which is connected to the reverse osmosis membrane separation device (4).

9. The integrated oily wastewater treatment device according to claim 8, characterized in that, The oil-water separation mesh (34) is stacked at an angle.

10. An integrated oily wastewater treatment device according to claim 3, characterized in that, The outer spherical surface of the adsorption ball (424) is provided with a ball bearing, which makes rolling contact with the inner wall of the hollow cavity of the hollow support (428).

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