An oil-containing sewage special treatment device and a use method thereof
By designing a floating plow-shaped scraper and a segmented output shaft for oil scraping, the problem of incomplete oil scraping caused by liquid level fluctuations was solved, and flexible cleaning of multi-stage filter layers was achieved, improving processing efficiency and maintenance convenience.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SUZHOU DONGDAREN SMART TECH
- Filing Date
- 2026-03-26
- Publication Date
- 2026-05-29
Smart Images
Figure CN122102285A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of water pollution technology, and in particular to a special treatment device and method for oily wastewater. Background Technology
[0002] Effective treatment of oily wastewater has always been a key issue in related processes. Common treatment methods typically rely on the density difference between oil and water, using static or dynamic separation techniques to achieve initial oil removal, such as inclined plate separators or fixed oil skimmers positioned at the top of the separation zone. Subsequently, the wastewater often needs to pass through multi-stage filtration units composed of filter media of varying precision to further remove suspended solids and residual oil, thereby meeting discharge or reuse standards. These methods generally follow a sequential treatment logic of separation followed by filtration.
[0003] However, existing methods still have several limitations in practice. Particularly in the primary separation stage, because the liquid level inside the filter often fluctuates with the influent, the fixedly installed oil skimming components cannot always maintain optimal contact with the floating oil layer, leading to incomplete skimming or unstable efficiency. Simultaneously, wastewater containing solid particles easily deposits rapidly in subsequent multi-stage filtration layers, causing blockages. Traditional overall backwashing or cleaning methods cannot differentiate cleaning for filter layers with varying degrees of contamination, affecting continuous operating efficiency and increasing maintenance complexity and energy consumption. Therefore, there is an urgent need for an integrated treatment solution that can efficiently remove oil adapting to changes in liquid level and allows for flexible and targeted cleaning of the filtration units. Summary of the Invention
[0004] Therefore, the technical problem to be solved by the present invention is that the existing technology has problems such as incomplete oil scraping caused by fluctuations in the filter liquid level and the inability to flexibly and independently clean the multi-stage filter layers, resulting in decreased processing efficiency and cumbersome maintenance.
[0005] The above-mentioned technical problems are solved by the following technical solution: This invention proposes a special treatment device for oily wastewater, including a cylindrical assembly with an inlet pipe, an oil outlet pipe, and a drain pipe on its outer shell; a drive motor, located at the top of the outer shell, with its output axis extending into the shell; and an oil scraping assembly, including a plow-shaped scraper, a float that keeps the plow-shaped scraper floating, and a transmission component that drivesly connects the plow-shaped scraper to the output shaft; under the action of the float, the working part of the plow-shaped scraper can always be kept in the oil layer at the liquid surface, wherein the oil scraping assembly is inclined relative to its rotation radius direction, so that it can guide the floating oil on the liquid surface to the oil outlet pipe when rotating.
[0006] In a preferred embodiment of the oily wastewater treatment device of the present invention: the surface of the plow-shaped scraper is curved or folded, and from the inner side near the output shaft to the outer side away from the output shaft, the surface has an upwardly inclined guide portion in the vertical direction.
[0007] In a preferred embodiment of the oily wastewater treatment device of the present invention: the tilt angle of the guide is configured such that when the plow-shaped scraper rotates with the output shaft, it can scrape the floating oil below the oil discharge pipe upward and guide it to the oil discharge pipe.
[0008] In a preferred embodiment of the oily wastewater treatment device of the present invention: the height of the plow-shaped scraper in the vertical direction is greater than the vertical distance between the center line of the oil discharge pipe and the preset working liquid level below it.
[0009] In a preferred embodiment of the oily wastewater treatment device of the present invention: the plow-shaped scraper is connected to the output shaft through the sleeve of the transmission member and rotates with it; the sleeve and the output shaft are connected by a key or spline. The float is fixedly connected to the surface of the plow-shaped scraper facing away from the direction of rotation. The float is a sealed hollow shell made of low-density foam material.
[0010] In a preferred embodiment of the oily wastewater treatment device of the present invention: the output shaft includes an upper shaft and a lower shaft connected by a one-way transmission mechanism; The oil scraping assembly is connected to the upper shaft section.
[0011] In a preferred embodiment of the oily wastewater treatment device of the present invention: the unidirectional transmission mechanism is configured such that when the drive motor drives the upper shaft to rotate in the first direction, the lower shaft does not rotate accordingly; when the drive motor drives the upper shaft to rotate in the second direction opposite to the first direction, the lower shaft rotates synchronously.
[0012] In a preferred embodiment of the oily wastewater treatment device of the present invention: a filter assembly is further provided inside the cylinder assembly below the oil scraping assembly; the rotation of the lower shaft is used to drive the moving parts in the filter assembly.
[0013] The above-mentioned technical problems are solved by the following technical solution: The present invention also proposes a method for using a special oily wastewater treatment device, including the aforementioned special oily wastewater treatment device, and comprising the following steps: Feeding and settling steps: The oily wastewater is introduced into the shell through the feed pipe and allowed to settle, so that the oil and water are separated to form an upper floating oil layer; Floating oil scraping steps: Start the drive motor to drive the output shaft to rotate the plow-shaped scraper in the first direction; under the action of the float, the cutting edge of the plow-shaped scraper is immersed in the floating oil layer below the liquid surface; the rotating plow-shaped scraper scrapes the floating oil with its inclined plate surface and guides it towards the oil drain pipe, so that the floating oil is finally discharged from the oil drain pipe. Drainage procedure: During or after oil scraping, the wastewater treated by oil scraping is discharged through the drain pipe, or filtered through the filter assembly before being discharged through the drain pipe.
[0014] In a preferred embodiment of the method of using the oily wastewater treatment device of the present invention: in the floating oil scraping step, the guiding force and centrifugal force of the plow-shaped scraper on the floating oil are adjusted by controlling the rotation speed of the output shaft to adapt to floating oil of different viscosities.
[0015] The beneficial effects of this invention are as follows: By using a plow-shaped scraper that floats with the liquid surface and its special inclined guide surface, the problem of low oil scraping efficiency caused by liquid level changes in traditional fixed oil scraping devices is completely solved, achieving stable and efficient removal of primary oil contaminants. Furthermore, through the design of a sleeve-type through-hole alignment mechanism and an integrated flipping scraper, combined with program-controlled forward and reverse motor rotation, targeted backwashing and contaminant extraction of multi-layer filter media can be achieved within a single device without disassembly. This greatly improves maintenance convenience and cleaning effect, and ensures the long-term stable operation of the filtration system. The entire system has a tight flow connection, a high degree of automation, and is energy-efficient. Attached Figure Description
[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Wherein: Figure 1 This is a schematic diagram of the overall structure of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the overall structure of the present invention. Figure 2 ; Figure 3 This is a schematic cross-sectional view of the overall structure of the present invention; Figure 4 This is a schematic diagram of the oil scraping component structure of the present invention. Figure 1 ; Figure 5 This is a schematic diagram of the oil scraping component structure of the present invention. Figure 2 ; Figure 6 This is a schematic diagram of the filter component structure of the present invention.
[0017] In the picture: 1. Cylinder assembly; 11. Outer shell; 12. Feed pipe; 13. Oil drain pipe; 14. Drain pipe; 15. Drive motor; 151. Output shaft; 1511. Upper shaft; 1512. Lower shaft; 152. One-way transmission mechanism; 2. Oil scraping assembly; 21. Plow-shaped scraper; 211. Plate surface; 212. Guide part; 213. Working part; 22. Float; 23. Transmission component; 231. Sleeve rod; 3. Filter assembly; 31. Filter basket; 32. Tilting scraper; 33. Sleeve component; 331. Inner sleeve; 332. Outer sleeve; 333. First through hole; 334. Second through hole; 34. Sewage pipe; 35. Pump. Detailed Implementation
[0018] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.
[0019] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.
[0020] Reference Figures 1-6 This embodiment provides a special treatment device for oily wastewater, including a cylindrical assembly 1, whose outer shell 11 is provided with a feed pipe 12, an oil discharge pipe 13 and a drain pipe 14; a drive motor 15, which is located on the top of the outer shell 11, and whose output shaft 151 extends into the body of the outer shell 11; and an oil scraping assembly 2, which includes a plow-shaped scraper 21, a float 22 that keeps the plow-shaped scraper 21 floating, and a transmission component 23 that drivesly connects the plow-shaped scraper 21 to the output shaft 151; under the action of the float 22, the working part 213 of the plow-shaped scraper 21 can always be kept in the oil layer at the liquid surface, wherein the oil scraping assembly 2 is inclined relative to its rotation radius direction, so that it can guide the floating oil on the liquid surface to the oil discharge pipe 13 when rotating.
[0021] The main body of this dedicated oily wastewater treatment device is a sealed cylindrical assembly 1, whose outer shell 11 forms the treatment chamber. An inlet pipe 12, an oil discharge pipe 13, and a drain pipe 14 are respectively located at appropriate positions on the outer shell 11. The inlet pipe 12 is located at the top and is used to introduce the oily wastewater to be treated; the oil discharge pipe 13 is located on the upper side and is specifically used to discharge collected floating oil; the drain pipe 14 is located at the bottom and is used to discharge treated water. Power is provided by a drive motor 15 installed at the top of the outer shell 11. The output shaft 151 of the drive motor 15 extends vertically downwards into the internal cavity of the outer shell 11, providing power to the internal rotating components.
[0022] This oil scraping assembly 2 is not fixedly installed, but designed as a dynamic floating type. It mainly consists of three parts: first, a plow-shaped scraper 21, which is specially designed to resemble a plowshare and has a working part 213 or cutting edge for cutting into and guiding the oil layer; second, a float 22, which is usually fixedly connected to the back of the plow-shaped scraper 21 (i.e., the non-working surface), and the buoyancy it provides ensures that the entire oil scraping assembly 2 can float freely with the rise and fall of the liquid level; and third, a transmission component 23, which connects the plow-shaped scraper 21 to the output shaft 151 of the motor, so that the power of the drive motor 15 can be transmitted to the plow-shaped scraper 21, while allowing the plow-shaped scraper 21 to have a certain degree of floating freedom in the radial and axial directions without affecting its floating state. During operation, after the oily wastewater enters the cavity and settles, the oil and water naturally separate due to the density difference, with the oil layer floating on the water surface. At this time, under the action of the float 22, the working part 213 (i.e., the cutting edge or guide surface) of the plow-shaped scraper 21 can automatically and always be immersed in the oil layer at the liquid surface, rather than in the water layer. This is a key point, ensuring the efficiency and targeting of the oil scraping action, and avoiding unnecessary energy waste and disturbance to the water body.
[0023] More importantly, the plow-shaped scraper 21 is not installed in a purely radial direction (i.e., directly pointing towards the center or the wall of the outer shell 11). It is "inclined relative to its rotation radius." This inclination, combined with the rotational motion, creates a guiding effect. When the drive motor 15 drives the oil scraping assembly 2 to rotate, the inclined plow-shaped scraper 21, after cutting into the oil layer, exerts a continuous, directional thrust on the floating oil. This thrust is precisely designed to point towards the "oil drain pipe 13." Therefore, under the "plowing" and guidance of the plow-shaped scraper 21, the floating oil is no longer simply pushed towards the cavity wall, but is effectively gathered and transported to the vicinity of the oil drain pipe 13. Finally, under hydrodynamic force, it is smoothly discharged when it rotates to the position of the oil drain pipe 13. This directional guidance mechanism greatly improves the efficiency and thoroughness of oil discharge, which is an important guarantee for the efficient oil-water separation of this device.
[0024] In summary, this embodiment describes a primary treatment device for oily wastewater that combines mechanical scraping with directional guidance and utilizes automatic floating to adapt to changes in liquid level. Its ingenious structure aims to efficiently and stably remove floating oil from the liquid surface.
[0025] The surface 211 of the plow-shaped scraper 21 is curved or folded, and from the inner side near the output shaft 151 to the outer side away from the output shaft 151, the surface 211 has an upwardly inclined guide portion 212 in the vertical direction. The inclination angle of the guide portion 212 is configured such that when the plow-shaped scraper 21 rotates with the output shaft 151, it can scrape the floating oil below the oil drain pipe 13 upward and guide it to the oil drain pipe 13.
[0026] First, the shape of the scraper surface 211 is defined as "curved or folded", which means that the working surface of the plow-shaped scraper 21 is not a simple vertical plane. It adopts a curved surface (such as an involute surface or a spiral surface) or a folded surface with a specific angle. This design is based on fluid dynamics considerations. This shape can cut into and carry viscous oil layers more smoothly, reduce flow resistance during rotation, and guide the oil to flow stably along the preset path (i.e., the scraper surface 211), avoiding oil-water mixing or oil droplet splashing, thus creating conditions for subsequent directional transportation.
[0027] Secondly, the key geometric features of the plate surface 211 in space were clarified: "From the inner side near the output shaft 151 to the outer side away from the output shaft 151, the plate surface 211 has an upwardly inclined guide section 212 in the vertical direction," defining the spatial orientation of the working surface of the plow-shaped scraper 21 as it extends from the rotation center area to the outer wall of the cylinder. Specifically, the inner edge of the plow-shaped scraper 21 (near the rotation shaft) is relatively low in vertical height, while as the plate surface 211 extends outward (away from the rotation shaft and closer to the cylinder wall), its entirety or key sections gradually rise upward, forming a "guide section 212" with a climbing slope, which essentially constructs a physical channel from low to high.
[0028] Finally, the specific functional effect to be achieved by this structural design is revealed, namely, solving the technical problem of "guiding low-level oil to high-level drain pipe 13". The statement that "the tilt angle of the guide part 212 is configured so that when the plow-shaped scraper 21 rotates with the output shaft 151, it can scrape up the floating oil below the liquid surface of the drain pipe 13 and guide it to the drain pipe 13" indicates that the upward tilt angle is not arbitrarily set, but is determined by precise calculation or optimization experiments based on factors such as the actual installation height of the drain pipe 13, the physical properties of the oil (such as viscosity), and the rotation speed. Its working principle is as follows: When the plow-shaped scraper 21 rotates with the shaft, the upwardly inclined plate surface 211 submerged in the oil layer will simultaneously apply a horizontal centrifugal thrust and a vertically upward lifting force to the oil in contact with it. Under this combined action, even floating oil located below the horizontal plane of the center line of the oil drain pipe 13 opening can be "scooped up" by the plow-shaped scraper 21 and transported obliquely upward along the upwardly inclined guide part 212. During the movement, the potential energy of the oil gradually increases, and it is eventually delivered to a position that is equal to or even higher than the height of the oil drain pipe 13. Thus, with the assistance of fluid dynamic pressure and the possible oil collection tank structure, it flows smoothly into the oil drain pipe 13 and completes the discharge.
[0029] In summary, this description defines a mechanical component that combines the functions of "scraping", "lifting" and "guiding". Its curved or folded surface shape optimizes fluid contact, while its unique spatial structure from the inside out and from the bottom up physically ensures the effective lifting and transportation of low-level floating oil to the high-level drain pipe 13. This is the key innovative design of this device that overcomes the shortcomings of conventional oil scrapers in handling low-level floating oil.
[0030] The vertical height of the plow-shaped scraper 21 is greater than the vertical distance between the centerline of the oil drain pipe 13 and the preset working liquid level below it. This height parameter is the fundamental guarantee that it can reliably and efficiently guide floating oil to the oil drain pipe 13 under variable liquid level conditions.
[0031] "The vertical height of the plow-shaped scraper 21" refers to the vertical dimension of the plow-shaped scraper 21 from its bottom edge or lowest working point to its top edge or highest point. "The vertical distance between the centerline of the oil drain pipe 13 and the preset working liquid level below it" defines the height difference between the stable oil-water interface (i.e., the surface where the floating oil layer mainly exists) and the horizontal plane where the center of the oil drain pipe 13 is located during normal operation (e.g., continuous inflow and outflow reaching equilibrium). The requirement that the former's height must be greater than the latter's vertical distance is primarily intended to ensure that the plow-shaped scraper 21 has sufficient "effective working depth." This means that regardless of how the "preset working liquid level" fluctuates within a certain range, the vertical structure of the plow-shaped scraper 21, starting from its submerged portion and extending upwards to its top, can always span and cover the entire height range from the "working liquid level" to the "center of the oil drain pipe 13."
[0032] The direct technical effects of this design are twofold: (1) Continuity of the entire guiding process: Since the height of the plow-shaped scraper 21 is sufficient to connect the low liquid level and the high oil drain pipe 13, the upwardly inclined "guide section 212" designed on its surface can form a complete and uninterrupted physical guiding channel that starts from the low point and ends at the oil drain pipe 13. After the oil is lifted from the liquid level by the plow-shaped scraper 21, it can be continuously transported upward along this sufficiently long guide surface until it reaches or exceeds the height of the oil drain pipe 13, thus smoothly flowing into the oil drain pipe 13. If the height of the plow-shaped scraper 21 is insufficient, the guiding channel will be "interrupted" in the middle, and the oil may fall in the middle and fail to reach the oil drain pipe 13. (2) Adaptability to liquid level fluctuations: In actual operation, small changes in the influent flow rate or composition may cause the working liquid level to rise or fall slightly near the preset value. Since the total height of the plow-shaped scraper 21 is greater than the fixed reference distance, it has reserved a safety margin for such normal liquid level fluctuations. Even if the liquid level is temporarily slightly lower than the usual "preset working liquid level", the part of the plow-shaped scraper 21 that is immersed still has enough depth to cut into the oil layer. At the same time, its top is always ensured to be higher than the center of the oil drain pipe 13, thus ensuring that no matter how the liquid level changes within the expected range, the functions of scraping oil and guiding upward will not fail due to insufficient height of the plow-shaped scraper 21, thus maintaining the stability and reliability of the device operation.
[0033] Therefore, this dimensional relationship is not a simple geometric specification, but a key design principle that matches the dynamic working characteristics of the floating plow-shaped scraper 21 with the static position of the oil drain pipe 13. It is a solid foundation to ensure that the "upward guidance" function can be effectively realized under any design conditions.
[0034] The output shaft 151 includes an upper shaft 1511 and a lower shaft 1512 connected by a one-way transmission mechanism 152. The one-way transmission mechanism 152 is configured such that when the drive motor 15 drives the upper shaft 1511 to rotate in a first direction, the lower shaft 1512 does not rotate accordingly; when the drive motor 15 drives the upper shaft 1511 to rotate in a second direction opposite to the first direction, the lower shaft 1512 rotates synchronously. Specifically, the one-way transmission mechanism 152 can be a one-way bearing.
[0035] The output shaft 151 of the device is not a continuous rigid shaft, but is designed as an upper shaft 1511 and a lower shaft 1512 that are physically independent of each other. The two shafts are connected by a "one-way transmission mechanism 152". The one-way transmission mechanism 152 identifies and responds to the direction of rotation. Its working logic is configured such that when the drive motor 15 drives the upper shaft 1511 to rotate in a specific "first direction" (e.g., counterclockwise), the one-way transmission mechanism 152 is in a "disengaged" or "slipping" state. The power is interrupted in this direction and cannot be transmitted to the lower shaft 1512. Therefore, the lower shaft 1512 remains stationary. Conversely, when the drive motor 15 drives the upper shaft 1511 to rotate in a "second direction" (e.g., clockwise) that is completely opposite to the first direction, the one-way transmission mechanism 152 immediately enters an "engaged" or "locked" state, reliably transmitting power to the lower shaft 1512, thereby keeping the lower shaft 1512 and the upper shaft 1511 rotating synchronously.
[0036] Its direct technical effect lies in the fact that the start, stop, and linkage of different downstream functional components can be controlled simply by changing the rotation direction of the drive motor 15. For example, in a typical application scenario, the upper shaft 1511 is specifically used to drive the floating oil scraping assembly 2 to perform oil scraping operations. When oil scraping is required, the motor drives the upper shaft 1511 to rotate in the "first direction," at which time the lower shaft 1512 does not work, avoiding unnecessary energy consumption or interference with other components below (such as the filter assembly 3). When another function needs to be started (such as backwashing or cleaning the filter assembly 3), simply control the motor to reverse and drive the upper shaft 1511 in the "second direction." At this time, the power is synchronously transmitted to the lower shaft 1512 through the engaged one-way transmission mechanism 152, which can drive the connected cleaning mechanism (such as the flipping scraper or drain valve) to start working.
[0037] By using a segmented output shaft 151 in conjunction with unidirectional transmission and a simple forward / reverse switching of the drive motor 15, two distinct operating modes—upper oil scraping and lower filtration cleaning—can be sequentially and independently controlled. Therefore, this segmented shaft combined with unidirectional transmission design essentially creates a "direction selection switch" built into the transmission chain. It eliminates the need for additional electromagnetic clutches or complex control valves; simply changing the motor's direction achieves purely mechanical selection and control of different working modules. This avoids configuring two independent drive systems for the two functional units, greatly simplifying the device structure, reducing costs and failure rates, and enabling automated sequential control of the process flow, ensuring continuous, efficient, and stable operation of the device.
[0038] The oil scraper assembly 2 is connected to the upper shaft 1511. The plow-shaped scraper 21 is connected to the upper shaft 1511 of the output shaft 151 through the sleeve 231 of the transmission component 23 and rotates with it. The sleeve 231 and the output shaft 151 are connected by a key or spline.
[0039] The oil scraping assembly 2 is not connected to the entire output shaft 151, but is specifically connected to the upper shaft 1511. This corresponds to the aforementioned one-way transmission mechanism 152 design, which means that the power of the oil scraping operation depends entirely on the rotation of the upper shaft 1511, and its working state (whether it rotates) is controlled by the drive motor 15 in a single direction. The logic is clear and the control is simple. The plow-shaped scraper 21 is not directly fixed to the upper shaft 1511, but is connected through a transmission component 23 called a "sleeve rod 231". This "sleeve rod 231" structure can be understood as having a collar at one end and a connecting rod at the other end. One end of the connecting rod is rigidly connected to the plow-shaped scraper 21, and the other end is sleeved on the outside of the upper shaft 1511. The power transmission between the two is achieved through a "key connection or spline connection". This means that longitudinal keyways or interlocking splines are respectively machined on the outer surface of the upper shaft 1511 and the inner surface of the sleeve rod 231. This connection method ensures that when the upper shaft 1511 rotates, the torque can be transmitted to the sleeve rod 231 synchronously and without slippage through the side contact of the key and the keyway (or the meshing of the spline teeth), thereby driving the plow-shaped scraper 21 to rotate stably and complete the oil scraping action.
[0040] This connection method, while ensuring reliable torque transmission, allows the sleeve 231, along with the plow-shaped scraper 21, a certain degree of axial freedom of movement. Because it uses a keyway fit rather than complete welding or bolt locking, the sleeve 231 can slide slightly up and down along the axial direction (vertical direction) of the upper shaft 1511. This small but crucial degree of freedom is the core of its cooperation with the "float 22" in the oil scraping assembly 2. When the liquid level rises or falls, the float 22 causes the entire oil scraping assembly 2 to rise or sink. At this time, the sleeve 231 can slide along the upper shaft 1511, ensuring that the working part 213 of the plow-shaped scraper 21 is always buoyant and precisely maintained in the oil layer, rather than being "stuck" at a fixed height due to a rigid connection with the shaft. The rigidity of power transmission and the flexibility of height adjustment are perfectly unified through the simple structure of "sleeve 231 + key connection". This connection design solves a seemingly contradictory requirement: to transmit strong rotational torque to scrape the oil layer, while also allowing the scraper to passively follow the float 22 in the vertical direction. By adopting a standard but ingenious mechanical connection method, it achieves the self-adaptation of the oil scraping assembly 2 to the liquid level without the need for complex sensors or active control, ensuring the high efficiency and stability of the oil scraping effect.
[0041] The float 22 is fixedly connected to the surface 211 of the plow-shaped scraper 21 facing away from the direction of rotation. The float 22 is a closed hollow shell made of low-density foam material.
[0042] This means that the float 22 is attached to the side of the scraper facing away from the incoming flow direction (i.e., the non-working surface) when the scraper rotates, and this positional design is crucial. During operation, the leading edge (working surface) of the scraper cuts into and pushes the oil layer, while the back side bears a certain amount of fluid resistance. Placing the float 22 on the back side reduces the impact of water flow, resulting in a more stable working state. More importantly, this layout helps to achieve torque balance in the oil scraping assembly 2. The buoyancy provided by the float 22 acts on the back side of the scraper, which can partially offset or balance the resistance torque experienced by the working surface of the oil scraping when pushing viscous oil, making the entire assembly run more smoothly during rotation, reducing swaying and uneven loading, and ensuring that the scraper edge maintains a uniform and consistent contact depth with the oil layer.
[0043] The sealed hollow shell of float 22 is typically made of corrosion-resistant metals (such as stainless steel or aluminum alloy) or engineering plastics, with its internal closed air cavity providing the primary buoyancy. This structure is robust and durable, able to withstand certain external pressures and water flow impacts, with stable buoyancy values that are not easily altered by water absorption or damage. It is suitable for treating wastewater in complex environments or containing fine solid particles. The low-density foam material of float 22, such as polyurethane foam, polyethylene foam, or expanded polystyrene (EPS), has a density much lower than water. Its interior is filled with numerous closed micropores, thus providing overall buoyancy. Foam material floats 22 are often lightweight, low-cost, and possess good flexibility and vibration absorption capabilities, better adapting to small fluctuations and impacts on the liquid surface. Whether using a hollow shell or foam material, the selection of materials must consider the chemical properties of the wastewater (such as acidity / alkalinity and solvent content) to ensure corrosion resistance and chemical stability, maintaining the long-term effectiveness of buoyancy. The total volume of the float 22 (or the weight of the water it displaces) needs to be precisely calculated to provide just enough buoyancy to ensure that the working part 213 of the plow-shaped scraper 21 can be submerged in the oil layer to a certain depth, but will not float too high and cause it to detach from the oil layer or affect the normal working liquid level.
[0044] Reference Figure 3 and Figure 6 Inside the cylinder assembly 1, below the oil scraping assembly 2, there is also a filter assembly 3; the rotation of the lower shaft 1512 is used to drive the moving parts in the filter assembly 3.
[0045] Inside the cylinder assembly 1, the oil scraping assembly 2 is not the only processing unit. Directly below it, a filter assembly 3 is also systematically installed. This layout forms a top-down stepped processing path: the oily wastewater first passes through the upper oil scraping assembly 2 to remove most of the floating oil, and then its effluent naturally falls into the lower filter assembly 3 for deep purification (such as removing suspended solids and residual oil).
[0046] Specifically, the filter assembly 3 in this device includes the following components: The filter assembly 3 is vertically installed inside the housing 11, directly below the oil skimmer assembly 2. Its main body consists of multiple independent and stacked filter baskets 31. Each filter basket 31 is a container-type structure with a porous bottom plate and side walls, used to hold specific types and specifications of filter media. This modular design allows for flexible configuration of the number of filtration stages and the type of filter media for different water quality treatment requirements.
[0047] A typical configuration involves loading different gradations of filter media from top to bottom. For example: the upper filter basket 31 is filled with relatively large-particle quartz sand, mainly serving as a coarse filter to trap larger suspended solids and some heavy oil remaining in the wastewater after oil skimming. The middle filter basket 31 is filled with lighter, more porous anthracite, serving as an intermediate filtration layer to further remove fine suspended solids and colloidal substances, and adsorb some oil. The lower filter basket 31 is filled with activated carbon with strong adsorption capacity, serving as a fine filtration layer, mainly used to adsorb dissolved organic matter, trace amounts of oil, decolorize and deodorize, ensuring the quality of the effluent.
[0048] The moving part includes one or more agitator scrapers 32 inside each filter basket 31, with their front ends designed as bevels for easy cutting and agitation of the filter media. It also includes a sleeve 33 located at the center of each filter basket 31 and penetrating the stack. It includes a fixed outer sleeve 332 and a vertically movable inner sleeve 331. The outer sleeve 332 has a set of first through holes 333 corresponding to the position of each filter basket 31, each hole communicating with the inner cavity of an agitator scraper 32. The inner sleeve 331 has second through holes 334 corresponding to the first through holes 333. The lower section 1512 of the output shaft 151 engages with the corresponding notch at the top of the inner sleeve 331 through a protrusion, which can drive the inner sleeve 331 to rotate and move it downward under certain conditions. The bottom of the outer sleeve 332 is connected to a drain pipe 34, which is equipped with a spring. Under normal conditions, the spring pushes the inner sleeve 331 to the upper position. At this time, the first through hole 333 and the second through hole 334 are misaligned, the cleaning channel is closed, and the outlet of the drain pipe 34 is connected to a suction pump 35.
[0049] The main function of filter assembly 3 is to receive the pre-treated effluent from oil skimming assembly 2 and remove residual pollutants from the water step by step using the physical interception and adsorption of multi-layer filter media. Its design goal is to achieve high filtration accuracy, long filtration cycle, and seamless integration with the oil skimming process. By sharing a drive control system with oil skimming assembly 2, the entire process of "oil skimming, filtration, and cleaning" is automated and integrated.
[0050] II. Workflow description of filter component 3: The working process of filter component 3 is closely linked to the operation mode of the entire device, and is mainly divided into two stages: "normal filtration process" and "maintenance and cleaning process".
[0051] Phase 1: Normal filtration process (in conjunction with oil skimming): After most of the floating oil is removed by the top oil skimmer 2, the wastewater flows naturally downwards into the filter assembly 3 under gravity. The wastewater first enters the uppermost filter basket 31, flows through the quartz sand layer, where large particles are effectively trapped. Subsequently, the water flows through the middle anthracite layer and the lower activated carbon layer. During this process, pollutants are removed step by step and classified, resulting in a stepped purification of the water. The "reclaimed water" after deep treatment by multiple layers of filter media collects at the bottom of the device and is finally discharged through an independent drain pipe 14, which can be reused or discharged in compliance with standards. At this stage, the drive motor 15 rotates forward (first direction), and only the upper shaft 1511 drives the oil skimmer 2. The lower shaft 1512 of the drive shaft rotates freely, and the moving parts inside the filter assembly 3 are stationary. The filtration process is completed entirely by gravity flow and the filtration and adsorption performance of the filter media itself.
[0052] Phase Two: Maintenance Cleaning Process (Independent Backwashing): When the filter assembly 3 has been running for a period of time, and the filter media layer experiences increased resistance and decreased filtration efficiency due to the trapping of pollutants, a cleaning process needs to be initiated. Stop the entry of oily wastewater. Close the drain pipe 14 or switch the valve. Control the drive motor 15 to reverse (second direction). At this time, the one-way transmission mechanism 152 engages, transmitting power to the lower shaft 1512. The lower shaft 1512 begins to rotate, directly driving the moving parts inside the filter assembly 3 (such as the flipping scrapers 32 in each filter basket 31) to begin working. The lower shaft 1512, through the cooperation of the protrusion and the notch of the inner sleeve 331, drives the inner sleeve 331 to move downwards against the spring force during rotation until the second through hole 334 on the inner sleeve 331 is completely aligned and connected with the first through hole 333 on the outer sleeve 332. Thus, each flipping scraper 32 connects with the central inner sleeve through the corresponding through hole group. The inner cavity of the sleeve 331 is connected and ultimately connected to the drain pipe 34. While the cleaning channel is open, the continuously rotating lower shaft 1512, through protrusions and notches, drives the inner sleeve 331 and its linked agitator scrapers 32 to slowly rotate within their respective filter baskets 31. The inclined surface at the front end of the agitator scrapers 32 continuously scrapes and agitates the filter media, loosening it. Clean water or air is introduced through the drain pipe 14 (or a specially designed backwash inlet), flowing counter-currently from bottom to top through each filter basket 31. This backwash water flow (or airflow) fully contacts the rotating and agitated filter media, stripping away the pollutants deeply trapped within the filter media. The stripped high-concentration pollutants, under the combined effect of the localized negative pressure generated by the rotation of the agitator scrapers 32 and the active extraction by the suction pump 35, flow through the openings on the agitator scrapers 32, through the aligned through-hole group, into the central channel of the inner sleeve 331, and are finally forcefully discharged through the drain pipe 34. This triple action of "mechanical agitation + hydraulic backwashing + centralized suction" achieves precise, efficient, and independent cleaning of each layer of filter media. After backwashing is completed, the motor stops. Under the reset action of the spring inside the drain pipe 34, the inner sleeve 331 is pushed back to its upper position, the first and second through holes 334 are misaligned, and the cleaning channel is closed. The device can then resume its normal "oil scraping-filtration" workflow.
[0053] In summary, the filter assembly 3 in this device achieves deep purification through a modular, multi-layer design, and its innovative linkage with the segmented drive shaft enables it to be uniformly controlled and efficiently self-cleaning. The entire workflow is logically clear, with the oil skimming and filtration functions working seamlessly together during normal operation and independently and efficiently during maintenance, jointly ensuring the long-term, stable, and efficient operation of the device.
[0054] Reference Figures 1-6 A method for using a dedicated oily wastewater treatment device includes the following steps: Feeding and settling steps: The oily wastewater is introduced into the outer shell 11 through the feed pipe 12 and settling to separate the oil and water, forming an upper floating oil layer; Floating oil scraping steps: Start the drive motor 15, drive the output shaft 151 to drive the plow-shaped scraper 21 to rotate in the first direction; under the action of the float 22, the cutting edge of the plow-shaped scraper 21 is immersed in the floating oil layer below the liquid surface; the rotating plow-shaped scraper 21 scrapes the floating oil with its inclined plate surface 211 and guides it towards the oil drain pipe 13, so that the floating oil is finally discharged from the oil drain pipe 13; wherein, by controlling the rotation speed of the output shaft 151, the guiding force and centrifugal force of the plow-shaped scraper 21 on the floating oil are adjusted to adapt to floating oil of different viscosities; Drainage steps: During or after oil scraping, the wastewater treated by oil scraping is discharged through drain pipe 14, or it is filtered through filter assembly 3 and then discharged through drain pipe 14.
[0055] Reference Figures 1-6 The workflow of this specialized oily wastewater treatment device mainly includes three core stages: oily wastewater injection and separation, floating oil skimming and preliminary treatment, and deep filtration and purification. The entire process is logically coherent and highly automated.
[0056] Step 1: Injection and settling of oily wastewater for separation: The oily wastewater to be treated is injected into the device through the feed pipe 12 on the outer shell 11. In the initial stage, the valve of the control drain pipe 14 is closed, allowing the liquid level to gradually rise inside the cylinder. The liquid level will eventually submerge the entire filter assembly 3 and stabilize at a preset working height below the center line of the oil drain pipe 13. During this settling process, the oil phase quickly rises to the water surface due to the natural density difference between oil and water, thus forming a continuous, collectable oil layer on the water surface.
[0057] Step 2: Co-treatment of floating oil skimmer and wastewater: Oil scraping start: Once the liquid level reaches and stabilizes at the preset height, open the drain pipe 14 valve. At this time, under the buoyancy provided by the float 22, the oil scraping assembly 2 floats as a whole, allowing the cutting edge or working part 213 of the plow-shaped scraper 21 to be precisely immersed in the floating oil layer below the liquid surface. Start the drive motor 15 and control it to rotate in the first direction (e.g., counterclockwise). The power of the drive motor 15 is transmitted through the upper section shaft 1511 of the output shaft 151. Since the plow-shaped scraper 21 is connected to the upper section shaft 1511 through the transmission component 23 (such as the sleeve 231), the scraper begins to rotate.
[0058] Highly efficient adaptive oil scraping: The rotating plow-shaped scraper 21 continuously "plows up" floating oil with its plate surface 211, which is inclined relative to the direction of rotation radius. In particular, the plate surface 211 has an upwardly inclined guide part 212, the inclination angle of which is specially configured. This allows the plow-shaped scraper 21 to not only collect floating oil when rotating, but also generate an upward component force to effectively scrape up floating oil located below the opening height of the oil drain pipe 13. Under the combined action of centrifugal force and the guidance of the plate surface 211, the floating oil is stably guided and collected to the oil drain pipe 13 on the side wall of the outer casing 11, and then continuously discharged from the device. The entire oil scraping process can adapt to the slight fluctuations of the liquid surface, ensuring that the oil scraping effect is always highly efficient and thorough.
[0059] Subsequent processing: After most of the floating oil has been scraped off, the wastewater can be directly discharged through the drain pipe 14 under gravity, or enter the next treatment unit. When the device is equipped with the filter assembly 3, the wastewater will flow from top to bottom through the assembly for deep filtration and purification. During this oil scraping operation, since the output shaft 151 contains an upper shaft 1511 and a lower shaft 1512 connected by a one-way transmission mechanism 152, when the upper shaft 1511 rotates in the first direction, the power will not be transmitted to the lower shaft 1512. Therefore, the moving parts in the filter assembly 3 remain stationary and do not affect the normal filtration or drainage process.
[0060] Step 3: Maintenance and cleaning of filter component 3: When the device is equipped with filter assembly 3 and it requires cleaning and regeneration, a special maintenance mode can be activated.
[0061] Mode switching and power transmission: Pause sewage injection and close relevant valves, control drive motor 15 to rotate in a second direction opposite to the first direction (e.g., clockwise). At this time, one-way transmission mechanism 152 engages, and power is synchronously transmitted to the lower section shaft 1512 of output shaft 151, causing it to start rotating.
[0062] Cleaning operation: The rotation of the lower shaft 1512 drives the moving parts in the filter assembly 3 (such as the internal turning or stirring mechanism) to start working, mechanically loosening the filter media. Simultaneously, cleaning water or air can be introduced from the bottom of the device to backwash the filter assembly 3. The dirt generated during cleaning can be discharged through a separate pipeline.
[0063] Resume standby: After cleaning is complete, stop the motor and reset all components. The device is then ready to begin the next "injection and oil skimming" work cycle.
[0064] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.
Claims
1. A dedicated treatment device for oily wastewater, characterized in that: It includes a cylinder assembly (1), on which a feed pipe (12), an oil drain pipe (13) and a drain pipe (14) are provided; a drive motor (15) is located on the top of the housing (11), and its output shaft (151) extends into the housing; The oil scraping assembly (2) includes a plow-shaped scraper (21), a float (22) for keeping the plow-shaped scraper (21) floating, and a transmission component (23) for drivingly connecting the plow-shaped scraper (21) to the output shaft (151). Under the action of the float (22), the working part (213) of the plow-shaped scraper (21) can always be kept in the oil layer at the liquid surface. The oil scraping assembly (2) is inclined relative to its rotation radius so that it can guide the floating oil on the liquid surface to the oil drain pipe (13) when rotating.
2. The oily wastewater treatment device according to claim 1, characterized in that: The surface (211) of the plow-shaped scraper (21) is curved or folded, extending from the inner side near the output shaft (151) to the outer side away from the output shaft (151). The surface (211) has an upwardly inclined guide portion (212) in the vertical direction.
3. The oily wastewater treatment device according to claim 2, characterized in that: The tilt angle of the guide part (212) is configured such that when the plow-shaped scraper (21) rotates with the output shaft (151), it can scrape the floating oil below the liquid surface of the oil drain pipe (13) upward and guide it to the oil drain pipe (13).
4. The oily wastewater treatment device according to claim 1, characterized in that: The vertical height of the plow-shaped scraper (21) is greater than the vertical distance between the center line of the oil drain pipe (13) and the preset working liquid level below it.
5. The oily wastewater treatment device according to claim 1, characterized in that: The plow-shaped scraper (21) is connected to the output shaft (151) through the sleeve (231) of the transmission component (23) and rotates with it. The sleeve (231) and the output shaft (151) are connected by a key or spline. The float (22) is fixedly connected to the surface (211) of the plow-shaped scraper (21) facing away from the rotation direction. The float (22) is a closed hollow shell made of low-density foam material.
6. The oily wastewater treatment device according to claim 1, characterized in that: The output shaft (151) includes an upper shaft (1511) and a lower shaft (1512) connected by a one-way transmission mechanism (152). The oil scraper assembly (2) is connected to the upper shaft (1511).
7. The oily wastewater treatment device according to claim 6, characterized in that: The one-way transmission mechanism (152) is configured such that when the drive motor (15) drives the upper shaft (1511) to rotate in the first direction, the lower shaft (1512) does not rotate accordingly; when the drive motor (15) drives the upper shaft (1511) to rotate in the second direction opposite to the first direction, the lower shaft (1512) rotates synchronously accordingly.
8. The dedicated oily wastewater treatment device according to claim 6 or 7, characterized in that: A filter assembly (3) is also provided inside the cylinder assembly (1) below the oil scraping assembly (2); the rotation of the lower shaft (1512) is used to drive the moving parts in the filter assembly (3).
9. A method of using a special treatment device for oily wastewater, characterized in that: The device includes the oily wastewater treatment apparatus according to any one of claims 1 to 8, and includes the following steps: Feeding and settling steps: The oily wastewater is introduced into the shell (11) through the feed pipe and settling is allowed to separate the oil and water, forming an upper floating oil layer; Floating oil scraping steps: Start the drive motor (15) to drive the output shaft (151) to rotate the plow-shaped scraper (21) in the first direction; under the action of the float (22), the working part (213) of the plow-shaped scraper (21) is immersed in the floating oil layer below the liquid surface; the rotating plow-shaped scraper (21) scrapes the floating oil with its inclined plate surface (211) and guides it towards the oil drain pipe (13), so that the floating oil is finally discharged from the oil drain pipe (13); Drainage steps: During or after oil scraping, the wastewater treated by oil scraping is discharged through the drain pipe (14), or filtered through the filter assembly (3) and then discharged through the drain pipe (14).
10. The method of using the oily wastewater treatment device according to claim 9, characterized in that: In the floating oil scraping step, the guiding force and centrifugal force of the plow-shaped scraper (21) on the floating oil are adjusted by controlling the rotation speed of the output shaft (151) to adapt to floating oil of different viscosities.