Oil-water separation device for oily wastewater treatment

Abstract

The utility model discloses an oil -water separation device for oil -containing wastewater treatment, including the sedimentation bin, steady flow bin, separation department and clear water bin that communicate in proper order. The sedimentation bin is used for intercepting and settling large -sized particle suspended matter, and the steady flow bin reduces and even water flow through overflow structure, and the separation department is equipped with multilayer inclined oil -wetted inclined plate of setting, and oil drop is gathered and floated, and the clear water bin water inlet side is equipped with oil -wetted hydrophobic coalescing filler plate, is used for the depth capture residual oil drop. The device top is equipped with the oil scraping unit that straddles the separation department, and it includes the purging mechanism for blowing the liquid level oil to the collection path, and the oil scraping mechanism for scraping the gathered oil to the oil collection groove. The utility model discloses through the integrated process of multistage cooperation and the active oil collection mode, realizes solid -liquid separation, oil -water high -efficient separation and floating oil thorough collection, solves the problem of the prior art in the pretreatment deficiency, separation efficiency is low, and the device integration is not high and so on.

Description

Technical Field

[0001] This utility model relates to the technical field, and in particular to an oil-water separation device for treating oily wastewater. Background Technology

[0002] Oily wastewater is a common pollutant discharged from various industrial sectors, including petrochemicals, machinery processing, food production, and shipping, as well as the catering service industry. The oil in this type of wastewater typically exists in various forms, such as floating oil, dispersed oil, emulsified oil, and dissolved oil. Direct discharge without effective treatment can severely damage aquatic ecosystems and lead to resource waste. Therefore, developing efficient and reliable oil-water separation technologies and devices is of great significance for environmental protection and sustainable development.

[0003] Currently, physical separation is one of the mainstream methods for treating oily wastewater, especially floatable and dispersed oil. Its core principle is to utilize the density difference between oil and water. Traditional gravity separation devices, such as horizontal flow oil separators (API separators), achieve separation by providing a sufficiently large settling area and a long hydraulic residence time, allowing oil droplets to naturally float to the liquid surface. However, these devices generally suffer from drawbacks such as large footprint, low efficiency in separating fine oil droplets, and weak resistance to fluctuations in hydraulic load, making them unsuitable for compact spaces or high-standard effluent requirements.

[0004] To improve separation efficiency and reduce equipment size, existing technologies often employ two main enhancement methods: one is to install inclined plates or inclined tubes in the separation zone, which significantly shortens the vertical distance for oil droplets to float and increases the effective separation area, thereby processing a larger volume of water or separating smaller oil droplets more efficiently per unit time; the other is to install coalescing packing made of oleophilic materials, which coarsens the fine dispersed oil droplets remaining in the water through adsorption and coalescence, making them larger and easier to float and separate, thereby improving the overall oil removal rate.

[0005] Despite this, existing oil-water separation devices still face several challenges in practical applications. First, there is insufficient process coordination and pretreatment: many devices are designed with a focus on the core coalescence and separation stages, neglecting the adaptability to influent water quality. If the influent carries a large amount of suspended solids, it can easily clog the coalescence packing or affect the flow field stability in the inclined plate zone; fluctuations in influent flow rate or water quality can also directly disrupt the laminar flow state required for inclined plate separation, leading to a decrease in separation efficiency. Second, the thoroughness and automation level of oil collection need optimization: for oil layers formed on the liquid surface in large-area separation zones, common overflow weirs have collection dead zones, especially when the oil layer is thin, resulting in low collection efficiency. Furthermore, mechanical scraping may cause redispersing of the separated oil layer or reemulsification of oil droplets. Utility Model Content

[0006] In view of this, the present invention provides an oil-water separation device for treating oily wastewater, in order to solve or improve the technical problems existing in the prior art.

[0007] The technical solution of this utility model embodiment is implemented as follows: an oil-water separation device for treating oily wastewater, comprising: The separation chamber contains a working chamber extending along its length. A sedimentation chamber, located at one end of the separation tank, is used to intercept large suspended solids in the incoming water and to achieve preliminary solid-liquid separation by gravity settling. A flow stabilizing chamber, located downstream of the sedimentation chamber, is used to reduce the water flow velocity and make the water flow more evenly distributed. The separation section, located downstream of the flow stabilizing chamber, has multiple inclined plates arranged along the water flow direction to induce oil droplet aggregation and floating. The clear water tank, located downstream of the separation section, has an oleophilic and hydrophobic coalescing packing plate on its inlet side for capturing and coalescing residual dispersed oil droplets in the water. An oil scraping unit is located at the top of the separation box and spans across the separation section. It has a purging mechanism and an oil scraping mechanism that cooperates with the purging mechanism to scrape off the floating oil that rises to the liquid surface. The sedimentation tank, flow stabilization tank, separation section, and clear water tank are arranged sequentially along the length of the working chamber and are interconnected. The oil scraping mechanism spans the liquid surface area above the separation section.

[0008] As an improvement, the sedimentation tank is located at the first end of the separation tank along the water flow direction. The top of the sedimentation tank has a water inlet trough, and the bottom has a drain valve. The top of the water outlet side wall of the sedimentation tank has an outlet hole that guides the upper water flow into the flow stabilizing tank. The bottom of the water inlet tank is provided with several filter holes.

[0009] As an improvement, the upper part of the outlet side wall of the stabilizing tank is provided with an overflow port, and the top height of the overflow port is lower than the bottom height of the outlet hole on the sedimentation tank, so that the water flows smoothly into the separation section in an overflow manner.

[0010] As an improvement, the separation section includes: A separation chamber is located downstream of the flow stabilization chamber and is connected to the flow stabilization chamber; Multiple inclined plates are fixedly installed inside the separation chamber, parallel to each other and spaced apart. Each inclined plate extends upward along the direction of water flow to guide oil droplets to coalesce and float upward along its surface.

[0011] As an improvement, the angle between the inclined plane of the inclined plate and the horizontal plane is 45° to 60°.

[0012] As an improvement, the oleophilic and hydrophobic coalescing packing plate is arranged perpendicular to the water flow direction and is fixedly installed on the water inlet side wall of the clear water tank facing the separation section.

[0013] As an improvement, the bottom of the clear water tank is provided with a drain outlet for discharging the purified water after it has been treated by the oleophilic and hydrophobic coalescing packing plate.

[0014] As an improvement, the purging mechanism includes: The purge frame is a horizontally arranged U-shaped structure with its opening side facing the other end of the separation chamber. The purge frame is fixedly installed along the top edge of the separation chamber. The purge nozzles are evenly spaced along the inner wall of the purge frame, and each purge nozzle faces the spray direction of the scraper movement trajectory of the oil scraping mechanism, and is used to blow the floating oil on the liquid surface to the oil scraping path.

[0015] As an improvement, the oil scraping mechanism includes: A drive motor is located at one end of the separation box corresponding to the separation compartment; A drive shaft is rotatably disposed along the length of the separation box, and one end of the drive shaft is connected to the output shaft of the drive motor. Multiple scrapers are provided and arranged circumferentially along the drive shaft, with the lower edge of each scraper positioned close to the liquid surface; An oil collection tank is located on one side of the separation box, at the end of the stroke of the scraper's rotation, and is used to collect the floating oil scraped by the scraper. The separator has an oil outlet on its side wall that communicates with the oil collection tank.

[0016] Compared with the prior art, the beneficial effects of this utility model are: This invention integrates multiple functional units—including large particle suspended solids interception and sedimentation, water flow rectification and uniform water distribution, inclined plate separation and coalescence, deep coalescence capture, and mechanical collection of floating oil—in an orderly and compact series arrangement along the water flow direction. This ensures that the influent undergoes thorough pretreatment sequentially, providing the core oil-water separation unit with relatively uniform water quality and stable flow conditions. It overcomes the reduction in separation efficiency caused by solid impurities or hydraulic fluctuations in existing technologies, achieving orderly and efficient coordination throughout the entire process from influent to effluent, significantly improving the operational stability and overall processing efficiency of the device.

[0017] This invention effectively shortens the oil droplet rising distance and increases the separation area by setting up inclined multi-layered plates. Simultaneously, the oleophilic surface of these plates promotes the collision, adhesion, and aggregation of oil droplets. Subsequently, an oleophilic-hydrophobic coalescing packing plate is installed at the outlet end to deeply capture and re-agglomerate the remaining fine oil droplets after passing through the inclined plate area. This forms a step-by-step oil droplet separation path from large to small, greatly improving the removal efficiency of tiny dispersed oil droplets, thereby enhancing the overall oil removal rate and achieving superior effluent water quality.

[0018] This invention incorporates a purging mechanism at the front end of the oil skimming mechanism. By using nozzles arranged in a specific direction to directionally purge the liquid surface, the thin layer of floating oil dispersed on the separation area's surface can be actively driven away and gathered into a preset oil skimming path. Subsequently, a rotating scraper thoroughly removes the gathered floating oil and transports it to an oil collection tank. This combination of active gathering and mechanical scraping effectively eliminates the collection blind spots present in traditional single-scraping methods, significantly improving the thoroughness and automation of floating oil collection, and avoiding redispersion problems that may be caused by excessively thick or stagnant oil layers.

[0019] In this invention, the various compartments are arranged sequentially along the length of the separation box and are directly connected, reducing unnecessary connecting pipes and transition spaces. The oil skimming unit spans across the separation area, maximizing space utilization. This not only makes the process flow compact and occupies a small area, but also reduces the manufacturing complexity and operation and maintenance costs of the device, facilitating its installation, transportation, and application as a modular unit.

[0020] The above overview is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features of the present invention will become readily apparent from the accompanying drawings and the following detailed description. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of the present invention. Figure 2 ; Figure 3 This is a schematic diagram of the internal structure of the present invention; Figure 4 This is a top view of the structure of this utility model; Figure 5 This is a side view of the structure of this utility model; Figure 6 for Figure 5 Sectional view at point AA.

[0023] Figure label: 1. Separate the box; 2. Sedimentation tank; 21. Inlet tank; 22. Drain valve; 23. Outlet hole; 3. Flow stabilizer; 31. Overflow outlet; 4. Separation section; 41. Inclined plate; 42. Separation chamber; 5. Clear water tank; 51. Oleophilic and hydrophobic coalescing packing plate; 52. Drain outlet; 6. Purging mechanism; 61. Purging frame; 62. Purging nozzle; 7. Oil scraping mechanism; 71. Drive motor; 72. Drive shaft; 73. Scraper; 74. Oil collection trough; 75. Oil outlet. Detailed Implementation

[0024] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this invention. Therefore, the drawings and description are considered exemplary in nature and not restrictive.

[0025] It is important to note that terms such as "first," "second," "symmetric," and "array" are used only to distinguish between descriptive and positional descriptions and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, features specified with terms such as "first" or "symmetric" may explicitly or implicitly include one or more of that feature; similarly, when the quantity of certain features is not limited by words such as "two" or "three," it should be noted that such features also explicitly or implicitly include one or more features. In this utility model, unless otherwise explicitly specified and limited, terms such as "installation," "connection," and "fixation" should be interpreted broadly; for example, they can refer to a fixed connection, a detachable connection, or an integral molding; they can refer to a mechanical connection, a direct connection, a welding connection, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the accompanying drawings and specific circumstances.

[0026] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0027] This utility model provides an oil-water separation device for treating oily wastewater, which can be referred to as follows. Figures 1-2 It includes a separation chamber 1, a sedimentation tank 2, a flow stabilizing tank 3, a separation section 4, a clear water tank 5, and an oil skimming unit. The separation chamber 1 has a working chamber extending along its length; the separation chamber 1 provides an orderly space for the oil-water separation process and ensures that the water flows sequentially along a preset path. Sedimentation tank 2 is located at one end of separation tank 1 to intercept large suspended solids in the incoming water and achieve preliminary solid-liquid separation by gravity settling; flow stabilization tank 3 is located downstream of sedimentation tank 2 to reduce water flow velocity and make water flow evenly distributed; separation section 4 is located downstream of flow stabilization tank 3 and has multiple inclined plates 41 arranged along the water flow direction to induce oil droplet aggregation and floating; clear water tank 5 is located downstream of separation section 4 and has an oleophilic and hydrophobic coalescing packing plate 51 located on its inlet side to capture and aggregate residual dispersed oil droplets in the water; oil scraping unit is located at the top of separation tank 1 and spans across separation section 4, has a purging mechanism 6 and an oil scraping mechanism 7 that cooperates with the purging mechanism 6 to scrape off floating oil that rises to the liquid surface; Among them, the sedimentation tank 2, the flow stabilization tank 3, the separation section 4 and the clear water tank 5 are arranged in sequence along the length of the working chamber and are interconnected with each other, and the oil scraping mechanism 7 spans the liquid surface area above the separation section 4.

[0028] As one implementation method of this embodiment, please refer to Figure 3 The sedimentation tank 2 is located at the first end of the separation box 1 along the water flow direction. The top of the sedimentation tank 2 has a water inlet trough 21, the bottom of the water inlet trough 21 has several filter holes, the bottom of the sedimentation tank 2 has a drain valve 22, and the top of the water outlet side wall of the sedimentation tank 2 has a water outlet hole 23 that guides the upper water flow into the flow stabilizing tank 3. Specifically, the inlet tank 21 is located at the top of the sedimentation tank 2 and is connected to the external inlet pipe. When oily wastewater flows into the inlet tank 21, its bottom filter holes can intercept larger particles such as fibers and debris, preventing them from entering the main body of the sedimentation tank 2 and avoiding blockage of subsequent pipes or interference with the sedimentation process. As a gravity sedimentation zone, the sedimentation tank 2 utilizes the density difference between solid particles and water. Under relatively slow water flow or static conditions, suspended solids naturally settle to the bottom of the tank under gravity, thus achieving preliminary solid-liquid separation. The drain valve 22 is installed at the bottom of the sedimentation tank 2 to discharge and collect the deposited sludge. It is used to periodically discharge the settled solids accumulated at the bottom of the sedimentation tank 2. The outlet hole 23 is located at the top of the outlet side wall of the sedimentation tank 2, controlling the outlet position to ensure that the clarified liquid with fewer solid particles in the upper layer of the sedimentation tank 2 after sedimentation can be discharged, effectively preventing the sludge deposited at the bottom from being carried away by the water flow and ensuring the solid-liquid separation effect.

[0029] In practice, oily wastewater first enters the inlet tank 21. As the wastewater passes through the filter holes at the bottom of the tank, large suspended solids larger than the holes are trapped inside, completing the first physical interception. The coarsely filtered wastewater then flows evenly into the sedimentation tank 2. At this point, the water flow velocity decreases significantly due to the increased space. Under the influence of gravity, the suspended solids in the wastewater (mainly settleable particles with a density greater than water) begin to settle vertically downwards, gradually detaching from the water flow and accumulating at the bottom of the tank.

[0030] Inside sedimentation tank 2, the water flow is approximately laminar. As solid particles settle, a clear stratification appears in sedimentation tank 2: a gradually thickening sludge layer at the bottom, and a clarified water layer (still containing oil and very fine suspended solids) at the top. The clarified upper water level rises continuously, and when it reaches the bottom height of outlet 23, it overflows from outlet 23 and flows smoothly into the downstream stabilization tank 3. The design of outlet 23 at the top ensures the discharge of clarified liquid.

[0031] Solid particles that settle to the bottom of sedimentation tank 2 accumulate and form sludge. Operators periodically open the drain valve 22 at the bottom to discharge the concentrated sludge, completing the solid-liquid separation and restoring the sedimentation tank to its effective settling volume.

[0032] As one implementation method of this embodiment, please refer to Figures 3-4 The upper part of the outlet side wall of the stabilizing chamber 3 is provided with an overflow port 31. The top height of the overflow port 31 is lower than the bottom height of the outlet hole 23 on the sedimentation chamber 2, so that the water flow smoothly enters the separation section 4 in an overflow manner. Specifically, the stabilizing chamber 3 is an independent chamber located downstream of the sedimentation chamber 2 and upstream of the separation section 4. It receives the water from the sedimentation chamber 2, consumes the excess kinetic energy of the water flow by expanding the flow cross-section, makes the turbulent or pulsating water flow gentle, and provides a uniformly distributed transition space for the water flow before entering the separation section 4.

[0033] Overflow port 31 is an opening on the upper part of the outlet side wall of the flow stabilizing chamber 3. It serves as the outlet weir of the flow stabilizing chamber 3 and determines the working liquid level maintained in the chamber. At the same time, along the width of overflow port 31, the water flows into the separation section 4 in a thin and uniform overflow manner, ensuring the uniformity of the water load of the subsequent treatment unit and avoiding dead water zones.

[0034] In practice, the water flow from the top outlet 23 of the sedimentation tank 2 first enters the stabilizing tank 3 with a certain speed and kinetic energy. Since the overflow port 31 is lower than the outlet 23, the water flow falls, thus converting part of the original kinetic energy of the water flow into potential energy changes and minor turbulent disturbances, effectively consuming the initial velocity.

[0035] After the water flows into the stabilizing chamber 3, its velocity decreases significantly due to the sudden expansion of the flow cross-section, based on the principle of fluid continuity. The water diffuses and mixes within the chamber, weakening the original velocity non-uniformity and directionality, thus allowing the water velocity to redistribute and become more uniform and slower.

[0036] As water continues to enter, the liquid level inside the tank gradually rises. When the liquid level rises to the top height of the overflow port 31, overflow begins. At this point, the liquid level inside the tank will be maintained at a stable level slightly higher than the top of the overflow port 31.

[0037] Once a stable liquid level is reached, the water flows gently along the entire width of the overflow port 31, forming a uniform thin layer of water, and smoothly overflows into the downstream separation section 4. This eliminates the jets or vortices that may be caused by pipe flow or orifice outflow, allowing the water to enter the core separation zone in a near-laminar flow state.

[0038] As one implementation method of this embodiment, please refer to Figure 3 and Figures 5-6 The separation section 4 includes an inclined plate 41 and a separation chamber 42. Among them, The separation chamber 42 is located downstream of the flow stabilizing chamber 3 and is connected to the flow stabilizing chamber 3; the separation chamber 42 provides an installation foundation and a stable working environment for the inclined plate 41, accommodates the water flow to be treated, and collects the floating oil that rises to the top after separation.

[0039] Multiple inclined plates 41 are fixedly installed inside the separation chamber 42, parallel to each other and spaced apart. Each inclined plate 41 extends upward along the water flow direction to guide oil droplets to coalesce and float upward along its surface. Specifically, the angle between the inclined plane of the inclined plate 41 and the horizontal plane is 45° to 60°.

[0040] Multiple inclined plates 41 are fixedly installed inside the separation chamber 42 in a parallel manner and at certain intervals, dividing the entire separation chamber 42 longitudinally into many parallel shallow structures, significantly shortening the vertical distance for oil droplets to rise to the collection surface. Simultaneously, the inclined plates 41 can change the flow pattern of the water, guiding the water flow parallel to the plate surface, which can guide the oil droplets to float. Furthermore, small oil droplets dispersed in the water move with the water flow, and when they collide with the oleophilic lower surface of the inclined plates, they are adsorbed and retained on the plates. Subsequent oil droplets continuously collide and merge, aggregating into larger oil droplets. Under the action of buoyancy, the aggregating large oil droplets slide upwards along the lower surface of the inclined plate, eventually detaching from the inclined plate and finally floating to the top liquid surface.

[0041] In practice, the steady flow of water overflowing from the stabilizing chamber 3 enters the separation chamber 42 and is distributed to the inlet end of the inclined plate 41. Due to the narrow and regular flow channels between the inclined plates 41, the water flow forms a stable laminar flow state after entering.

[0042] Carried by the water flow, tiny oil droplets flow parallel to the inclined plate 41. Due to Brownian motion, water drag, and density difference, the oil droplets deviate from their streamlines and collide with the lower surface of the inclined plate 41. Since the surface of the inclined plate 41 is usually treated with oleophilic modification, the oil droplets adhere to the plate surface. Subsequent oil droplets continuously undergo the same collision and adhesion, merging (coalescing) with the already attached oil droplets to form an oil film or oil droplet with continuously increasing volume.

[0043] When the accumulated oil droplets are large enough that the buoyant force they experience is sufficient to overcome the adhesion and shear force of the water flow, the large oil droplets or oil clumps begin to slide upwards along the inclined plate. The large oil droplets that detach from the inclined plate 41 rise rapidly and eventually accumulate on the top surface of the separation chamber, forming a floating oil layer.

[0044] As one implementation method of this embodiment, please refer to Figure 3 and Figure 6 The oleophilic and hydrophobic coalescing packing plate 51 is set perpendicular to the water flow direction and is fixedly installed on the water inlet side wall of the clear water tank 5 facing the separation section 4.

[0045] The bottom of the clear water tank 5 is provided with a drain outlet 52 for discharging the purified water after it has been treated by the oleophilic and hydrophobic coalescing packing plate 51.

[0046] Specifically, the clear water tank 5 serves as a clear water storage area. It provides a stable working space for the oleophilic and hydrophobic coalescing packing plate 51 and accommodates the effluent after final purification.

[0047] The oleophilic and hydrophobic coalescing packing plate 51 has a strong adsorption affinity for oil droplets in water. When water flows through it, the dispersed oil droplets are firmly captured by the packing fibers or surface. The captured oil droplets accumulate and merge inside or on the surface of the packing, forming oil droplets or oil films much larger than their initial size. Under the action of buoyancy, the large oil droplets detach from the packing surface and float to the top of the liquid surface in the separation chamber 42.

[0048] In practice, water flowing out of the separation section 4 enters the clear water chamber through the oleophilic and hydrophobic coalescing packing plate 51. The water flows directly over the oleophilic and hydrophobic coalescing packing plate 51, which is vertically installed on the water inlet side, and the water flow is dispersed and makes full contact with its oleophilic surface area.

[0049] Tiny, dispersed oil droplets remaining in the water flow that are too small to float effectively on the inclined plate 41 are adsorbed onto the surface of the packing fibers or pores due to their oleophilic and hydrophobic properties as they flow over the oleophilic and hydrophobic coalescing packing plate 51. Subsequently, the oil droplets collide and merge with the adsorbed oil droplets, resulting in deep coalescence and causing the oil droplets to grow larger inside the packing.

[0050] When the oil droplets formed by aggregation are large enough, the buoyancy they experience exceeds the adsorption force on the packing surface and the shear force of the water flow, causing the large oil droplets to be released from the packing surface. Subsequently, they float vertically upwards in the separation chamber 42 and accumulate on the liquid surface at the top of the chamber.

[0051] The purified water flows into the clean water tank 5 and is discharged continuously or intermittently through the drain outlet 51, completing the entire treatment process.

[0052] As one implementation method of this embodiment, please refer to Figure 2 and Figure 4 The purging mechanism 6 includes a purging frame 61 and a purging nozzle 62. Among them, The purge frame 61 has a horizontally arranged U-shaped structure, with its opening side facing the other end of the separation chamber 42. The purge frame 61 is fixedly installed along the top edge of the separation chamber 42. Specifically, the purge frame 61 is a horizontally arranged U-shaped rigid frame, with its opening side facing the other end of the separation chamber, i.e., the end where the oil scraping mechanism 7 is installed. The U-shaped inner wall of the purge frame 61 forms a three-sided enclosed physical boundary, which can limit the range of action of the purge fluid to a rectangular area on the liquid surface of the separation chamber 42 and guide the floating oil on the liquid surface to the opening side of the purge frame 61.

[0053] The purge nozzles 62 are evenly spaced along the inner wall of the purge frame 61, with each nozzle facing the trajectory of the scraper of the oil scraping mechanism 7. They are used to purge floating oil from the liquid surface to the scraping path. The purge nozzles 62, evenly spaced along the inner wall of the purge frame 61, eject gas jets that impact the liquid surface, generating shear and thrust forces on the floating oil film, thus gathering and pushing the floating oil dispersed over a larger liquid surface area to the scraper 73.

[0054] In practice, when the oil scraping program is started, the purging mechanism 6 operates first or simultaneously. Externally supplied fluid (such as low-pressure air) is sprayed at a certain angle onto the liquid surface of the separation chamber 42 through the purging nozzle 62. Since the purging nozzle 62 is arranged along the inner side of the purging frame 61, the jet forms a flow field above the liquid surface that converges from the U-shaped closed side to the open side.

[0055] The oil layer dispersed on the surface of the separation chamber 42, especially floating in areas far from the scraper path, begins to move along the liquid surface in the direction of spray under the surface shear force generated by the purging jet. The purging nozzles 62 on both sides of the purging frame 61 act as guides, preventing the oil from spreading to both sides, and constraining it and gradually converging it towards the central area of ​​the opening of the purging frame 61.

[0056] As one implementation method of this embodiment, please refer to Figures 3-4 The oil scraping mechanism 7 includes a drive motor 71, a drive shaft 72, a scraper 73, and an oil collection trough 74. Among these, The drive motor 71 is located at one end of the separation box 1 corresponding to the separation chamber 42; the drive motor 71 serves as a power source, providing the rotational power and torque required for the operation of the oil scraping mechanism 7.

[0057] The drive shaft 72 is rotatably arranged along the length of the separation box 1, and one end of the drive shaft 72 is connected to the output shaft of the drive motor 71. The drive shaft 72 receives the torque and rotational motion transmitted by the drive motor 71 and transmits it to all the scrapers 73 fixedly mounted on it, so that they move synchronously.

[0058] Multiple scrapers 73 are provided and arranged circumferentially along the drive shaft 72, with the lower edge of each scraper 73 close to the liquid surface; When rotating, the lower edge of the scraper 73 is immersed in or close to the liquid surface, pushing and gathering the floating oil layer in front of it forward (i.e., along the direction of rotation).

[0059] The oil collection trough 74 is located on one side of the separation box 1, at the end of the stroke of the scraper 73, and is used to collect the floating oil scraped by the scraper 73; wherein, the side wall of the separation box 1 is provided with an oil outlet 75 that communicates with the oil collection trough 74.

[0060] The oil collection tank 74 is a trough-shaped container located on one side of the separation box 1, and at the end of the stroke of the scraper 73. When the scraper 73 pushes the floating oil to the oil outlet 75, it falls into the oil collection tank 74 for centralized storage.

[0061] In practice, the drive motor 71 starts and drives all the scrapers 73 to rotate slowly via the drive shaft 72. When the lower edge of the rotating scraper 73 passes the liquid surface, it pushes the oil layer that has been pre-aggregated by the purging mechanism 6 or naturally floated forward along the liquid surface.

[0062] When the scraper 73 pushes the floating oil to the oil outlet 75, it falls into the oil collection tank 74 for centralized storage. The floating oil that falls into the oil collection tank 74 collects in the tank. Due to the separation of oil and water, a small amount of entrained water will sink to the bottom of the tank, while the floating oil will be on the top layer. Finally, the floating oil can be discharged through the oil outlet on the side wall of the oil collection tank 74 and enter an external oil storage container.

[0063] In specific implementation, this utility model 1) Sedimentation of large suspended particles and preliminary solid-liquid separation: Oily wastewater first enters the inlet tank 21 at the top of the sedimentation tank 2 at the starting end of the device through an external pipe. The bottom of the tank is equipped with filter holes to perform preliminary filtration of the inlet water, intercepting large floating or suspended debris such as fibers and debris, and preventing them from entering subsequent units and causing blockages.

[0064] Wastewater enters the main body of sedimentation tank 2 after passing through the filter holes. The water flow velocity is significantly slowed down due to the increased flow cross-section. Settled solid particles with a density greater than water (such as sand and some sludge) gradually detach from the water flow under gravity, sink vertically, and accumulate at the bottom of the tank, forming a sludge layer. At the same time, oily wastewater forms a relatively clear water layer at the top (still containing oil and fine suspended solids). The clarified upper layer of water overflows through the outlet hole 23 located at the top of the outlet side wall of sedimentation tank 2. The sludge deposited at the bottom of the tank can be discharged and collected by periodically opening the drain valve 22 at the bottom of the tank, completing the initial solid-liquid separation.

[0065] 2) Water flow rectification and uniform water distribution: The water overflowing from sedimentation tank 2 enters the downstream stabilization tank 3. Since the top of the overflow port 31 of stabilization tank 3 is lower than the bottom of the outlet 23 of sedimentation tank 2, the water enters in a cascading manner, consuming some of its kinetic energy. Within stabilization tank 3, the flow velocity further decreases and becomes more uniform due to the expanded cross-sectional area. Turbulence or pulsation is smoothed out, and the flow becomes stable. As water continues to flow in, the liquid level in the tank slowly rises to the height of the overflow port 31 and remains stable. Finally, the water flows smoothly into the separation section 4 in a thin, uniform weir flow across the entire width of the overflow port.

[0066] 3) Inclined plate separation and oil droplet coalescence and floating: A steady flow of water enters the separation chamber 42 of the separation unit 4 and is distributed into narrow channels between parallel, spaced-apart inclined plates 41. The inclined plates 41 are installed at an angle of 45° to 60°. The water flows forward in a laminar state between the inclined plates 41. Oil droplets (with a density less than water) carried in the wastewater continuously collide with and adhere to the lower surface of the oleophilic inclined plates 41 due to Brownian motion, water flow drag, and their own buoyancy. Subsequent oil droplets continue to collide, adhere, and coalesce with already attached droplets, forming larger oil droplets or oil films. As the aggregates grow larger, when the component of the buoyancy along the inclined plane of the plate 41 is sufficient to overcome the adhesion force and water flow shear force, the large oil droplets or oil clumps begin to slide obliquely upwards along the inclined plate surface, eventually detaching from the plate surface. After detachment, the oil droplets float vertically upwards under buoyancy, converging at the top liquid surface of the separation chamber 42 to form a continuous oil layer.

[0067] 4) Deep capture and coalescence of residual dispersed oil: After being treated by the inclined plate 41, the water flows into the clear water tank 5 and first flows directly across the oleophilic and hydrophobic coalescing packing plate 51, which is vertically installed on the inlet side. This packing plate has an extremely large oleophilic and hydrophobic specific surface area. As the water flows through its complex fiber or pore structure, micron-sized dispersed oil droplets are strongly adsorbed and captured by the packing surface. The captured oil droplets further collide and merge inside or on the surface of the packing, achieving deep coalescence and forming larger oil droplets. Under the action of buoyancy, the larger oil droplets detach and release from the packing surface and float back to the liquid surface of the separation tank 42 for further collection. After this deep treatment, the oil content in the water is significantly reduced, and the purified water accumulates at the bottom of the clear water tank 5 and is discharged through the drain outlet 52 at the bottom of the tank, completing the water purification process.

[0068] 5) Collection, scraping, and removal of floating oil on the liquid surface: The floating oil layer that accumulates on the top surface of the liquid in the separation chamber 42 is mechanically removed by an oil skimming unit. This unit includes a purging mechanism 6 and an oil skimming mechanism 7, which work together.

[0069] The purging nozzles 62 of the purging mechanism 6 are evenly arranged along the inner wall of the U-shaped purging frame 61. When oil drainage is required, the purging nozzles 62 spray gas (such as low-pressure air) obliquely towards the liquid surface. The generated jet creates a shear force on the liquid surface, pushing and converging the floating oil dispersed in a large area, especially near the closed side of the purging frame 61, towards the open side of the purging frame 61, i.e., near the working path of the oil scraping mechanism 7.

[0070] The drive motor 71 of the oil skimming mechanism 7 starts, driving the drive shaft 72 and multiple scrapers 73 arranged circumferentially on it to rotate slowly. The lower edge of the rotating scrapers 73 is close to or slightly immersed in the liquid surface, continuously pushing the floating oil layer that has been swept and gathered forward along the liquid surface (towards one side of the device). When the floating oil pushed by the scrapers 73 reaches the oil outlet 75 on the side wall of the separation tank 1, it overflows the weir under the push of the scrapers and falls into the outer oil collection tank 74. The floating oil accumulates in the oil collection tank 74, and the small amount of water that may be carried may sink to the bottom of the tank. The floating oil can be discharged to the external oil storage container through the outlet pipe on the tank, realizing the recovery of waste oil.

[0071] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in this utility model, and these should all be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.

Claims

1. An oil-water separation device for treating oily wastewater, characterized in that, include: The separation box (1) has a working chamber extending along its length. A sedimentation chamber (2) is located at one end of the separation box (1) to intercept large suspended solids in the incoming water and to achieve preliminary solid-liquid separation by gravity settling. A flow stabilizing chamber (3) is located downstream of the sedimentation chamber (2) to reduce the water flow velocity and make the water flow more uniform. The separation section (4) is located downstream of the flow stabilizing chamber (3) and has multiple inclined plates (41) arranged at an angle along the water flow direction to induce oil droplets to coalesce and float. The clear water tank (5) is located downstream of the separation section (4) and has an oleophilic and hydrophobic coalescing packing plate (51) on its inlet side for capturing and coalescing residual dispersed oil droplets in the water. The oil scraping unit is located at the top of the separation box (1) and spans across the separation section (4). It has a purging mechanism (6) and an oil scraping mechanism (7) that cooperates with the purging mechanism (6) to scrape off the floating oil that rises to the liquid surface. The sedimentation tank (2), the flow stabilizing tank (3), the separation section (4) and the clear water tank (5) are arranged sequentially along the length of the working chamber and are interconnected. The oil scraping mechanism (7) spans the liquid surface area above the separation section (4).

2. The oil-water separation device for treating oily wastewater according to claim 1, characterized in that, The sedimentation tank (2) is located at the first end of the separation box (1) along the water flow direction. The sedimentation tank (2) has a water inlet trough (21) at the top and a drain valve (22) at the bottom. The top of the water outlet side wall of the sedimentation tank (2) has a water outlet hole (23) that guides the upper water flow into the flow stabilizing tank (3). The bottom of the water inlet tank (21) is provided with several filter holes.

3. The oil-water separation device for treating oily wastewater according to claim 2, characterized in that, The upper part of the outlet side wall of the stabilizing tank (3) is provided with an overflow port (31). The top height of the overflow port (31) is lower than the bottom height of the outlet hole (23) on the sedimentation tank (2) so that the water flow smoothly enters the separation section (4) in an overflow manner.

4. The oil-water separation device for treating oily wastewater according to claim 1, characterized in that, The separation section (4) includes: A separation chamber (42) is located downstream of the flow stabilizing chamber (3) and is connected to the flow stabilizing chamber (3); Multiple inclined plates (41) are provided and are fixedly installed inside the separation chamber (42) in parallel and at intervals. Each inclined plate (41) extends upward along the water flow direction to guide oil droplets to coalesce and float upward along its surface.

5. The oil-water separation device for treating oily wastewater according to claim 4, characterized in that, The angle between the inclined plane of the inclined plate (41) and the horizontal plane is 45° to 60°.

6. The oil-water separation device for treating oily wastewater according to claim 1, characterized in that, The oleophilic and hydrophobic coalescing packing plate (51) is arranged perpendicular to the water flow direction and is fixedly installed on the water inlet side wall of the clear water tank (5) facing the separation part (4).

7. The oil-water separation device for treating oily wastewater according to claim 1, characterized in that: The bottom of the clear water tank (5) is provided with a drain outlet (52) for discharging the purified water after it has been treated by the oleophilic and hydrophobic coalescing packing plate (51).

8. The oil-water separation device for treating oily wastewater according to claim 4, characterized in that, The purging mechanism (6) includes: The purge frame (61) has a horizontally arranged U-shaped structure with its opening side facing the other end of the separation chamber (42). The purge frame (61) is fixedly arranged along the edge of the top of the separation chamber (42). The purge nozzles (62) are evenly spaced along the inner sidewall of the purge frame (61), and the spray direction of each purge nozzle (62) is toward the scraper movement trajectory of the oil scraping mechanism (7), which is used to blow the floating oil on the liquid surface to the oil scraping path.

9. The oil-water separation device for treating oily wastewater according to claim 8, characterized in that, The oil scraping mechanism (7) includes: A drive motor (71) is disposed at one end of the separation box (1) corresponding to the separation chamber (42); A drive shaft (72) is rotatably arranged along the length of the separation box (1), and one end of the drive shaft (72) is connected to the output shaft of the drive motor (71). Multiple scrapers (73) are provided and arranged circumferentially along the drive shaft (72), with the lower edge of each scraper (73) being close to the liquid surface; An oil collection trough (74) is provided on one side of the separation box (1) and located at the end of the stroke of the scraper (73) during rotation. It is used to collect the floating oil scraped by the scraper (73). The separation box (1) has an oil outlet (75) on its side wall that communicates with the oil collection tank (74).

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